4,709 research outputs found
Deactivation of TEM-1 beta-Lactamase investigated by isothermal batch and non-isothermal continuous enzyme membrane reactor methods
The thermal deactivation of TEM-1 β-lactamase was examined using two experimental techniques: a series of isothermal batch assays and a single, continuous, non-isothermal assay in an enzyme membrane reactor (EMR). The isothermal batch-mode technique was coupled with the three-state Equilibrium Model of enzyme deactivation, while the results of the EMR experiment were fitted to a four-state molten globule model . The two methods both led to the conclusions that the thermal deactivation of TEM-1 β -lactamase does not follow the Lumry-Eyring model and that the Teq of the enzyme (the point at which active and inactive states are present in equal amounts due to thermodynamic equilibrium) is at least 10 °C from the Tm (melting temperature), contrary to the idea that the true temperature optimum of a biocatalyst is necessarily close to the melting temperature
Research Think Tank: "Complexifying" International Communication and Communication Technology
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66530/2/10.1177_108056999706000413.pd
Internationalism, Technological Innovation, and New Associations: Bringing Change to Business Communication Research and Teaching
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68267/2/10.1177_108056999906200418.pd
Recent Decisions
Comments on recent decisions by John Rogers, Thomas S. Calder, Edward S. Mraz, Cornelius Jerome Smith, Allan C. Schmid, and Ralph R. Blume
High-grade B-Cell lymphoma with MYC and BCL6 rearrangements associated with Richter transformation of chronic lymphocytic leukemia
Richter transformation (RT), or Richter syndrome, is defined as the transformation of chronic lymphocytic leukemia (CLL) to an aggressive B-cell lymphoma. The vast majority, up to 99%, transform into diffuse large B-cell lymphoma (DLBCL), with a small subset (<1%) becoming classical Hodgkin lymphoma. Approximately half of RT cases progress through a pathway involving dysregulation of C-MYC. High-grade B-cell lymphoma (HGBL) is a recent diagnostic category of aggressive B-cell lymphomas set forth in the updated 2017 WHO Classification of Hematopoietic and Lymphoid Tissues. HGBL with MYC and BCL2 and/or BCL6 rearrangements, formerly “double-hit” and “triple-hit” lymphomas, comprise the majority of HGBL cases. Patients with HGBL have a worse prognosis than those with diffuse large B-cell lymphoma. We present a case of RT with rearrangements of MYC and BCL6. To our knowledge, there are no reported cases of RT with a “double-hit” lymphoma genotype
Results from EDGES High-Band: II. Constraints on Parameters of Early Galaxies
We use the sky-average spectrum measured by EDGES High-Band ( MHz) to
constrain parameters of early galaxies independent of the absorption feature at
~MHz reported by Bowman et al. (2018). These parameters represent
traditional models of cosmic dawn and the epoch of reionization produced with
the 21cmFAST simulation code (Mesinger & Furlanetto 2007, Mesinger et al.
2011). The parameters considered are: (1) the UV ionizing efficiency (),
(2) minimum halo virial temperature hosting efficient star-forming galaxies
(), (3) integrated soft-band X-ray luminosity (), and (4) minimum X-ray energy escaping the first
galaxies (), corresponding to a typical H column
density for attenuation through the interstellar medium. The High-Band spectrum
disfavors high values of and , which correspond
to signals with late absorption troughs and sharp reionization transitions. It
also disfavors intermediate values of , which
produce relatively deep and narrow troughs within the band. Specifically, we
rule out
( C.L.). We then combine the EDGES High-Band data with constraints on the
electron scattering optical depth from Planck and the hydrogen neutral fraction
from high- quasars. This produces a lower degeneracy between and
than that reported in Greig & Mesinger (2017a) using
the Planck and quasar constraints alone. Our main result in this combined
analysis is the estimate ~~ ( C.L.). We leave for future work the evaluation of
~cm models using simultaneously data from EDGES Low- and High-Band.Comment: Accepted in Ap
Recent Decisions
Comments on recent decisions by Lawrence A. Kane, Jr., Vernon O. Teofan, Thomas S. Calder, John Rogers, James Carroll Booth, Paul M. Kraus, Jack Economou, and Robert P. Gorman
The First Passage Probability of Intracellular Particle Trafficking
The first passage probability (FPP), of trafficked intracellular particles
reaching a displacement L, in a given time t or inverse velocity S = t/L, can
be calculated robustly from measured particle tracks, and gives a measure of
particle movement in which different types of motion, e.g. diffusion, ballistic
motion, and transient run-rest motion, can readily be distinguished in a single
graph, and compared with mathematical models. The FPP is attractive in that it
offers a means of reducing the data in the measured tracks, without making
assumptions about the mechanism of motion: for example, it does not employ
smoothing, segementation or arbitrary thresholds to discriminate between
different types of motion in a particle track. Taking experimental data from
tracked endocytic vesicles, and calculating the FPP, we see how three molecular
treatments affect the trafficking. We show the FPP can quantify complicated
movement which is neither completely random nor completely deterministic,
making it highly applicable to trafficked particles in cell biology.Comment: Article: 13 pages, 8 figure
A novel drug management system in the Febuxostat versus Allopurinol Streamlined Trial:A description of a pharmacy system designed to supply medications directly to patients within a prospective multicenter randomised clinical trial
Background: Trials of investigational medicinal products are required to adhere to strict guidelines with regard to the handling and supply of medication. Information technology offers opportunities to approach clinical trial methodology in new ways. This report summarises a novel pharmacy system designed to supply trial medications directly to patients by post in the Febuxostat versus Allopurinol Streamlined Trial.Method: A bespoke web-based software package was designed to facilitate the direct supply of trial medications to Febuxostat versus Allopurinol Streamlined Trial participants from a pharmacy based in the Medicines Monitoring Unit, University of Dundee.Results: To date, 65,467 packs of medication have been dispensed using the system to 3978 patients. Up to 238 packs per day have been dispensed.Conclusion: The Medicines Monitoring Unit Febuxostat versus Allopurinol Streamlined Trial drug management system is an effective method of administering the complex drug supply requirements of a large-scale clinical trial with advantages over existing arrangements. A low rate of loss to follow-up in the Febuxostat versus Allopurinol Streamlined Trial may be attributable to the drug management system.</p
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