Pharmacokinetics of cyclophosphamide and its metabolites in bone marrow transplantation patients

Classical swine fever virus infection of pigs causes a severe leukopenia and immunosuppression. In the present study, the kinetics of virus infection, and identification of target cells for the virus in peripheral blood were analysed. Virus infection was often not detectable before 5-7 days p.i. A minority of animals yielded detectable infected cells at 3 days p.i., but < 5% PBMC. It was not until 10 days p.i. that this figure increased-to 35-70% PBMC depending on the animal. Detailed analysis of Ficoll-Hypaque-purified PBMC identified the major population to be SWC3+SWC8+CD14+MHCII- granulocytic cells. Microscopic observations determined that these low density granulocytic cells in the PBMC from CSFV infected animals were indeed immature cells. Both the low density granulocytic cells and monocytes were major targets for CSFV infection in the peripheral blood. This is the first demonstration that low density granulocytic cells dominate the blood leukocyte population during CSF, and that such cells are targets for virus infection. The present work also demonstrates that the leukocyte population changes, such as B lymphocyte depletion and the relative dominance of myeloid cells in the blood during CSF, occur before virus infection of the affected cells. Thus, the pathological mechanism therein is not a direct consequence of virus infection.     

Patency of 24-gauge peripheral intermittent infusion devices: a comparison of heparin and saline flush solutions

The purpose of this study was to compare the effectiveness of heparin and normal saline flush solutions in maintaining the patency of 24-gauge peripheral intermittent infusion devices (PIIDs). A prospective, non-randomized, sequential, blinded study design was conducted on a pediatric and a neonatal intensive care unit. The sample consisted of 134 catheters in 61 patients. Heparin and saline flush groups were similar for age, PIID placement site, irritating substances infused, and initial IV function. The median duration of catheters flushed with heparin was 42 hours and with saline was 35.3 hours. Kaplan-Meier Survival Analysis indicated that the duration of catheters flushed with heparin was significantly longer than those flushed with saline (p = .02). More catheters flushed with saline were removed because of problems (p = .027). Results of this study suggest that heparin is more effective than saline in maintaining the patency of small, 24-gauge catheters.     

Tracking the mind during reading via eye movements: Comments on Kliegl, Nuthmann, and Engbert (2006).

R. Kliegl, A. Nuthmann, and R. Engbert (see record 2006-01956-002) reported an impressive set of data analyses dealing with the influence of the prior, present, and next word on the duration of the current eye fixation during reading. They argued that outcomes of their regression analyses indicate that lexical processing is distributed across a number of words during reading. The authors of this comment question their conclusions and address 4 different issues: (a) whether there is evidence for distributed lexical processing, (b) whether so-called parafoveal-on-foveal effects are widespread, (c) the role of correlational analyses in reading research, and (d) problems in their analyses because they use only cases in which words are fixated exactly once. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experimental Demonstration of a Detection-Time-Bin-Shift Polarization Encoding Quantum Key Distribution System

Detection-time-bin-shift (DTBS) is a scheme that uses time division multiplexing of a single photon detector between two photon bases in a quantum key distribution (QKD) system. This scheme can simplify the structure of a QKD system, reduce its cost and overcome the security problems caused by the dead-time induced self-correlation and the unbalanced characteristics of detectors. In this paper, we introduce an improved DTBS scheme and implement it based on our previously developed conventional fiber-based QKD system using the B92 protocol. Our DTBS QKD system generates sifted keys at a rate of more than 1 Mbit/s with a quantum bit error rate (QBER) lower than 2% over 1.1 km of fiber.     

Busulfan-glutathione conjugation catalyzed by human liver cytosolic glutathione S-transferases

We have examined the catalytic activity of glutathione S-transferases (GST) in the conjugation of busulfan with glutathione (GSH) in human liver cytosol, purified human liver GST, and cDNA-expressed GST-alpha 1-1. Human liver microsomes and cytosol were incubated with 40 microM busulfan and 1 mM GSH. Cytosol catalyzed the formation of the GSH-busulfan tetrahydrothiophenium ion (THT+) in a concentration-dependent manner, whereas microsomes lacked activity. The total and spontaneous rates of THT+ formation increased with pH (pH range, 6.50-7.75), with the maximum difference at pH 7.4. Due to the limited aqueous solubility of busulfan, a K(m) for busulfan was not determined. The intrinsic clearance (Vmax/K(m)) of busulfan conjugation was 0.167 microliter/min/mg with 50-1200 microM busulfan and 1 mM GSH. GSH Vmax and K(m) for busulfan conjugation were 30.6 pmol/min/mg and 312 microM, respectively. Ethacrynic acid (0.03-15 microM) inhibited cytosolic busulfan-conjugating activity with 40 microM busulfan and 1 mM GSH. Enzyme-mediated THT+ formation was decreased 97% by 15 microM ethacrynic acid with no effect on the spontaneous reaction. In incubations with affinity-purified liver GST and GST-alpha 1-1, the intrinsic clearance for busulfan conjugation was 0.87 and 2.92 microliters/min/mg, respectively. Busulfan is a GST substrate with a high K(m) relative to concentrations achieved clinically (1-8 microM).     

Class-ABD amplifier

A new multilevel form of switching amplifier is introduced, whose operation is based on the class-AD variable-frequency variable-mark/space-ratio amplifier. It offers practical advantages in reducing important circuit losses when applied to RL loads     

INTERFACIAL TRANSPORT PHENOMENA INVITED REVIEW

Interfacial transport phenomena include all effects associated with momentum, energy, and mass transfer at phase interfaces.

I shall begin by examining the nature of the phase interface and associated common lines. I then will develop the general balance equations at each point within a phase, at each point on a dividing surface, and at each point on a common line. Mass conservation, momentum transfer, energy transfer, and mass transfer are treated as special cases.     

Reduced Surfactant Uptake in Three Dimensional Assemblies of VOx Nanotubes Improves Reversible Li+ Intercalation and Charge Capacity

The relationship between the nanoscale structure of vanadium pentoxide nanotubes and their ability to accommodate Li⁺ during intercalation/deintercalation is explored. The nanotubes are synthesized using two different precursors through a surfactant‐assisted templating method, resulting in standalone VO _x (vanadium oxide) nanotubes and also “nano‐urchin”. Under highly reducing conditions, where the interlaminar uptake of primary alkylamines is maximized, standalone nanotubes exhibit near‐perfect scrolled layers and long‐range structural order even at the molecular level. Under less reducing conditions, the degree of amine uptake is reduced due to a lower density of V⁴⁺ sites and less V₂O₅ is functionalized with adsorbed alkylammonium cations. This is typical of the nano‐urchin structure. High‐resolution TEM studies revealed the unique observation of nanometer‐scale nanocrystals of pristine unreacted V₂O₅ throughout the length of the nanotubes in the nano‐urchin. Electrochemical intercalation studies revealed that the very well ordered xerogel‐based nanotubes exhibit similar specific capacities (235 mA h g^?1) to Na⁺‐exchange nanorolls of VO_x (200 mA h g^?1). By comparison, the theoretical maximum value is reported to be 240 mA h g^?1. The VOTPP‐based nanotubes of the nano‐urchin 3D assemblies, however, exhibit useful charge capacities exceeding 437 mA h g^?1, which is a considerable advance for VO_x based nanomaterials and one of the highest known capacities for Li⁺ intercalated laminar vanadates.