Novel DNA assay for cytomegalovirus detection: comparison with conventional culture and pp65 antigenemia assay

We compared conventional cytomegalovirus (CMV) isolation, rapid viral culture, a CMV pp65 antigenemia assay, and a novel CMV DNA hybrid capture system (HCS). A total of 309 blood samples from individuals in different risk groups were assessed by at least two of the methods mentioned above. Leukocytes were recovered either after centrifugation in Leucosep tubes containing 1.080 Ficoll for pp65 assay or after simple differential lysis steps for DNA detection. HCS was based on DNA hybridization with a CMV RNA probe and its capture by antibodies to DNA-RNA hybrids. The CMV pp65 lower matrix protein was detected by fluorescence with c10-c11 monoclonal antibody in formalin-fixed leukocytes. Concordant results were observed for 92.9, 78.3, and 82.7% of the patients when comparing (i) viral culture and the pp65 antigenemia assay, (ii) viral culture and HCS, and (iii) the pp65 antigenemia assay and HCS, respectively. Discordant results were observed between a positive HCS result and negative culture and/or pp65 results. These results were associated with relatively low DNA levels (< 20 pg/10(6) cells) and positive viruria. In conclusion, the pp65 antigenemia assay is a rapid and reliable method of detecting CMV and is preferable to culture, but the Murex HCS appears to be more sensitive for CMV detection.     

Anicteric cholestasis in a 75-year-old man

This presentation challenges the purveyors of the importance of "positive thinking" in the cure of cancer. Psychological support should allow the patient to come to terms with his or her situation in a way that works for that individual within a caring and realistic environment. In no way should psychological support add an extra burden to an already devastated patient. By forcing "positive mental attitude", health-care professionals are not allowing patients to face reality. Promoters of the "cure" that comes with positive thinking are quoted, as well as authors who question the promoters' intent and outcome. It is felt that "positive thinking" may be appropriate as one of many successful coping strategies. To attribute more to it or, worse, to insist that patients believe in its power to cure may be courting emotional disaster.     

Acetylcholine-induced potassium current of guinea pig outer hair cells: its dependence on a calcium influx through nicotinic-like receptors

The cholinergic efferent inhibition of mammalian outer hair cells (OHCs) is mediated by a hyperpolarizing K+ current. We have made whole-cell tight-seal recordings from single OHCs isolated from the guinea pig cochlea to characterize the mechanism by which acetylcholine (ACh) activates K+ channels. After ACh application, OHCs exhibited a biphasic response: an early depolarizing current preceding the predominant hyperpolarizing K+ current. The current-voltage (I-V) relationship of the ACh-induced response displayed an N-shape, suggesting the involvement of Ca2+ influx. When whole-cell recording was combined with confocal calcium imaging, we simultaneously observed the ACh-induced K+ current (IK(ACh)) and a Ca2+ response restricted to the synaptic area of the cell. This IK(ACh) could be prevented by loading OHCs with 10 mM of the fast Ca2+ buffer bis(2-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid (or BAPTA), therefore allowing the observation of the ACh-induced early current in isolation. This early current revealed nicotinic features because it activated with an intrinsic delay in the millisecond range, reversed nearly in between potassium and sodium equilibrium potentials, and was blocked by curare. However, it was strongly reduced in the absence of external Ca2+, and its I-V relationship displayed an unusual outward rectification at positive membrane potentials and an inward rectification below -60 mV. The results indicate that the cholinergic response of mammalian OHCs involves a "nicotinic-like" nonspecific cation channel through which Ca2+ enters and triggers activation of nearby Ca2+-dependent K+ channels.     

Potential of the crude glycerol and citric acid mixture as a binder in medium-density fiberboard manufacturing

European Journal of Wood and Wood Products - Urea–formaldehyde (UF) resin is the main commercial adhesive used for medium-density fiberboard (MDF) manufacturing. UF resin is used to produce...     

Differences in preschool children's conceptual strategies when thinking about animate entities and artifacts.

Two-, 3-, and 4-year-old children viewed 10 stimulus sets. Each set contained a sample picture (e.g., a dog), a basic-level taxonomic match (e.g., another dog), a thematic match (e.g., a bone), and an irrelevant match (e.g., a pen). The children were asked to choose a match that "goes with" each sample. Sample pictures were either animate entities or artifacts. The children's choice behavior indicated that a shift occurs between 3 and 4 years of age from a taxonomic bias to a thematic bias and that, at both ages, animate sample stimuli enhance the children's tendency to adopt thematic conceptual strategies. These data are consistent with recent suggestions that thematic thinking presupposes basic-level taxonomic thinking during early conceptual development and that this developmental progression occurs more rapidly in some domains of knowledge than in others. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Model for Polymer Composite Wear Behavior Including Preferential Load Support and Surface Accumulation of Filler Particulates

A rule-of-mixtures model is developed for the time-dependent wear and friction behavior of polymer matrix materials containing particulate filler inclusions, based upon the specific wear rates of filler and matrix materials. The model accounts for the accumulation of wear-resistant filler particles within the near-surface region of the composite as sliding proceeds. Account is also made for preferential support of the normal load by filler particles at the sliding surface. Though particle/matrix interfacial shear stress and particle aspect ratio do affect initial transient behavior, wear rate, and friction are independent of preferential load support under steady-state conditions. The model indicates that steady-state composite wear rate can be most affected by the specific wear resistance of the filler particles, as well as the volume fraction filling of particles into the polymer matrix.     

Performance of exterior semitransparent PVDF–acrylic coatings

The purpose of this study was to investigate the performance of a semitransparent PVDF–acrylic coating on two wood species: Black spruce and White pine. An accelerated aging test was performed on the PVDF–acrylic coating and the results obtained were compared with those obtained for a water-based acrylic coating. Color changes were found to be more significant for the acrylic coating, especially after 1000 h of exposure, and for the White pine panels. Infrared spectroscopy revealed that the acrylic resin was more affected by the accelerated aging test than the PVDF resin, although X-ray photoelectron spectroscopy revealed that PVDF was slightly affected at the extreme surface (first 10 nm). Star-shaped defects were found at the surface of the White pine panels finished with the PVDF–acrylic coating. Experiments revealed that the PVDF–acrylic coating does not seem to be flexible enough to sustain resin exudation or other stresses.     

Purification, molecular cloning, and functional expression of the human nicodinamide-adenine dinucleotide phosphate-regulated thyroid hormone-binding protein

The kidney and several other thyroid hormone-responsive tissues contain a NADP-regulated thyroid hormone (TH)-binding protein (THBP), with an apparent molecular mass of 36 kDa on SDS-PAGE, responsible for most of the intracellular high-affinity T3 and T4 binding. THBP was purified to homogeneity from human kidney cytosol and used to generate proteolytic peptides. Microsequencing of four peptides revealed identity to amino acid sequences deduced from a human cDNA homolog to a cDNA encoding kangaroo mu-crystallin. This protein is a major structural kangaroo lens protein with no known function in other species. A full-sized cDNA (TH5.9) was isolated by 5'- and 3'-rapid amplification of cDNA ends using a human brain cDNA library and gene-specific PCR primers, confirming identity to the previously cloned human cDNA. The TH5.9 cDNA encodes a 314-residue protein (theoretical mol wt = 33,775) with significant homologies (40 to 60%) with two bacterial enzymes: lysine cyclodeaminase and ornithine cyclodeaminase. The TH5.9 cDNA was expressed in Escherichia coli as a glutathione S-transferase (GST) fusion protein. Purified GST fusion protein, but not GST, bound T3 specifically with high affinity [dissociation constant (Kd) = 0.5 nM] in the presence of NADPH, and was labeled by UV-driven cross-linking of underivatized [(125)I]T3. T3 binding and photoaffinity labeling of GST fusion protein were activated by NADPH [activation constant (K[act]) = 10(-8) M], but not by NADH. The expressed protein displays the appropriate binding properties, indicating that TH5.9 cDNA encodes the NADP-regulated THBP characterized in human tissues.