2,089 research outputs found
Two Decades of Publishing Excellence in Pharmaceutical Biotechnology
Recombinant biological products have revolutionized modern medicine by providing both remarkably effective vaccines to prevent disease and therapeutic drugs to treat a wide variety of unmet medical needs. Since the early 1980s, dozens of new therapeutic protein drugs and macromolecular vaccines have been commercialized, which have benefitted millions of patients worldwide. The pharmaceutical development of these biological products presented many scientific and technical challenges, some of which continue today with newer candidates including recombinant protein-based vaccines with novel adjuvants, peptide and RNA-based drugs, and stem cellular therapies. Compared with small molecule drugs, the characterization, stabilization, formulation, and delivery of biomolecules share common hurdles as well as unique challenges. This area of drug development research has been referred to as “pharmaceutical biotechnology”, in recognition of the critical role that recombinant DNA technology plays in the design and production of most of these biological products. Current research focus areas in this field include (i) determination of structural integrity of the primary sequence, post-translational modifications, and higher-order three dimensional shapes, (ii) assessment of physicochemical degradation pathways and their effects on biological activity and potency, (iii) formulation design and development to optimize stability and delivery, (iv) evaluating and optimizing process development steps including lyophilization and fill-finish, (v) analytical method development and applications of new instruments and data visualization tools, (vi) design and development of drug delivery approaches, and (vii) studies of biological effects including pharmacokinetics, pharmacodynamics, and adverse immunogenicity.
During the early days of pharmaceutical biotechnology research, there were numerous scientific challenges because the analytical characterization approaches needed for development of recombinant biological molecules in “real world” pharmaceutical dosage forms were essentially unknown. Furthermore, understanding critical drug product manufacturing issues (e.g., stability of biological compounds during processing, storage, and shipping as well as reproducibility of fill-finish production technologies) and behavior during and after patient administration was often achieved by “on-the-job” training. Fortunately, the pioneers in the field regularly presented research at key conferences and started publishing early in pharmaceutical sciences journals such as Journal of Pharmaceutical Sciences. Recognizing this critically important new field, the then Editor of the journal, Professor Bill Higuchi, instituted a new “pharmaceutical biotechnology” category for research papers. This insightful move was coupled with an equally wise decision to recruit Dr. C. Russell Middaugh as the new Associate Editor for the new research category. As will be detailed below, under Dr. Middaugh’s diligent and expert guidance, pharmaceutical biotechnology papers have grown in number, scope, and impact over the past 20 years, and these days, the Journal of Pharmaceutical Sciences is viewed by scientific leaders in the field as the “go to” place for publication of the most important results and descriptions of innovations in pharmaceutical biotechnology
A study of the static yield stress in a binary Lennard-Jones glass
The stress-strain relations and the yield behavior of model glass (a 80:20
binary Lennard-Jones mixture) is studied by means of MD simulations. First, a
thorough analysis of the static yield stress is presented via simulations under
imposed stress. Furthermore, using steady shear simulations, the effect of
physical aging, shear rate and temperature on the stress-strain relation is
investigated. In particular, we find that the stress at the yield point (the
``peak''-value of the stress-strain curve) exhibits a logarithmic dependence
both on the imposed shear rate and on the ``age'' of the system in qualitative
agreement with experiments on amorphous polymers and on metallic glasses. In
addition to the very observation of the yield stress which is an important
feature seen in experiments on complex systems like pastes, dense colloidal
suspensions and foams, further links between our model and soft glassy
materials are found. An example are hysteresis loops in the system response to
a varying imposed stress. Finally, we measure the static yield stress for our
model and study its dependence on temperature. We find that for temperatures
far below the mode coupling critical temperature of the model (),
\sigmay decreases slowly upon heating followed by a stronger decrease as
\Tc is approached. We discuss the reliability of results on the static yield
stress and give a criterion for its validity in terms of the time scales
relevant to the problem.Comment: 14 pages, 18 figure
Optical Spectroscopy of Supernova 1993J During Its First 2500 Days
We present 42 low-resolution spectra of Supernova (SN) 1993J, our complete
collection from the Lick and Keck Observatories, from day 3 after explosion to
day 2454, as well as one Keck high-dispersion spectrum from day 383. SN 1993J
began as an apparent SN II, albeit an unusual one. After a few weeks, a
dramatic transition took place, as prominent helium lines emerged in the
spectrum. SN 1993J had metamorphosed from a SN II to a SN IIb. Nebular spectra
of SN 1993J closely resemble those of SNe Ib and Ic, but with a persistent
H_alpha line. At very late times, the H_alpha emission line dominated the
spectrum, but with an unusual, box-like profile. This is interpreted as an
indication of circumstellar interaction.Comment: 19 pages plus 13 figures, AASTeX V5.0. One external table in AASTeX
V4.0, in landscape format. Accepted for publication in A
Engineered swift equilibration of a Brownian particle
A fundamental and intrinsic property of any device or natural system is its
relaxation time relax, which is the time it takes to return to equilibrium
after the sudden change of a control parameter [1]. Reducing relax , is
frequently necessary, and is often obtained by a complex feedback process. To
overcome the limitations of such an approach, alternative methods based on
driving have been recently demonstrated [2, 3], for isolated quantum and
classical systems [4--9]. Their extension to open systems in contact with a
thermostat is a stumbling block for applications. Here, we design a
protocol,named Engineered Swift Equilibration (ESE), that shortcuts
time-consuming relaxations, and we apply it to a Brownian particle trapped in
an optical potential whose properties can be controlled in time. We implement
the process experimentally, showing that it allows the system to reach
equilibrium times faster than the natural equilibration rate. We also estimate
the increase of the dissipated energy needed to get such a time reduction. The
method paves the way for applications in micro and nano devices, where the
reduction of operation time represents as substantial a challenge as
miniaturization [10]. The concepts of equilibrium and of transformations from
an equilibrium state to another, are cornerstones of thermodynamics. A textbook
illustration is provided by the expansion of a gas, starting at equilibrium and
expanding to reach a new equilibrium in a larger vessel. This operation can be
performed either very slowly by a piston, without dissipating energy into the
environment, or alternatively quickly, letting the piston freely move to reach
the new volume
Health Status Outcomes in Patients With Acute Myocardial Infarction After Rehospitalization
Background Rehospitalizations after acute myocardial infarction for unplanned coronary revascularization and unstable angina (UA) are common. However, despite the inclusion of these events in composite end points of many clinical trials, their association with health status has not been studied. Methods and Results We included 3283 patients with acute myocardial infarction enrolled in a prospective, 24-center US study who had rehospitalizations independently classified by experienced cardiologists. Health status was assessed using Seattle Angina Questionnaire and EuroQol-5D Visual Analog Scale. In the propensity-matched cohorts, 1-year health status was compared between those who did and did not experience rehospitalization for UA or revascularization using a hierarchical linear model. Overall, mean age was 59 years, 33% were women, and 70% were white. Rehospitalization rates for UA and unplanned revascularization at 1 year were 4.3% and 4.7%. One-year Seattle Angina Questionnaire summary scores were worse in patients with rehospitalizations for UA (mean difference, -10.1; 95% confidence interval, -12.4 to -7.9) and unplanned revascularization (mean difference, -5.7; 95% confidence interval, -8.8 to -2.5) when compared with patients without such rehospitalizations. Similarly, EuroQol-5D Visual Analog Scale scores were worse among patients with such readmissions. Individual Seattle Angina Questionnaire domains indicated worse 1-year angina and quality of life outcomes among patients rehospitalized for UA or unplanned revascularization. Conclusions Within the first year after acute myocardial infarction, rehospitalizations for UA and unplanned revascularization are associated with worse health status. These findings highlight the impact of such events from a patient's perspective, beyond their economic impact and support the use of UA and unplanned revascularization as elements of composite end points
Cis and Trans Effects of Human Genomic Variants on Gene Expression
This work was funded by the Louis-Jeantet Foundation (http://www.jeantet.ch/), the European Research Council (Grant ID: 260927 http://erc.europa.eu/), the Swiss National Foundation (Grant ID: 130342 http://www.snf.ch), NCCR Frontiers In Genetics (http://www.frontiers-in-genetics.org), the UK Medical Research Council (http://www.mrc.ac.uk) and the Wellcome Trust (Grant ID: 092731).
Uncoupling Protein-4 (UCP4) Increases ATP Supply by Interacting with Mitochondrial Complex II in Neuroblastoma Cells
Mitochondrial uncoupling protein-4 (UCP4) protects against Complex I deficiency as induced by 1-methyl-4-phenylpyridinium (MPP+), but how UCP4 affects mitochondrial function is unclear. Here we investigated how UCP4 affects mitochondrial bioenergetics in SH-SY5Y cells. Cells stably overexpressing UCP4 exhibited higher oxygen consumption (10.1%, p<0.01), with 20% greater proton leak than vector controls (p<0.01). Increased ATP supply was observed in UCP4-overexpressing cells compared to controls (p<0.05). Although state 4 and state 3 respiration rates of UCP4-overexpressing and control cells were similar, Complex II activity in UCP4-overexpressing cells was 30% higher (p<0.05), associated with protein binding between UCP4 and Complex II, but not that of either Complex I or IV. Mitochondrial ADP consumption by succinate-induced respiration was 26% higher in UCP4-overexpressing cells, with 20% higher ADP:O ratio (p<0.05). ADP/ATP exchange rate was not altered by UCP4 overexpression, as shown by unchanged mitochondrial ADP uptake activity. UCP4 overexpression retained normal mitochondrial morphology in situ, with similar mitochondrial membrane potential compared to controls. Our findings elucidate how UCP4 overexpression increases ATP synthesis by specifically interacting with Complex II. This highlights a unique role of UCP4 as a potential regulatory target to modulate mitochondrial Complex II and ATP output in preserving existing neurons against energy crisis
Networking - A Statistical Physics Perspective
Efficient networking has a substantial economic and societal impact in a
broad range of areas including transportation systems, wired and wireless
communications and a range of Internet applications. As transportation and
communication networks become increasingly more complex, the ever increasing
demand for congestion control, higher traffic capacity, quality of service,
robustness and reduced energy consumption require new tools and methods to meet
these conflicting requirements. The new methodology should serve for gaining
better understanding of the properties of networking systems at the macroscopic
level, as well as for the development of new principled optimization and
management algorithms at the microscopic level. Methods of statistical physics
seem best placed to provide new approaches as they have been developed
specifically to deal with non-linear large scale systems. This paper aims at
presenting an overview of tools and methods that have been developed within the
statistical physics community and that can be readily applied to address the
emerging problems in networking. These include diffusion processes, methods
from disordered systems and polymer physics, probabilistic inference, which
have direct relevance to network routing, file and frequency distribution, the
exploration of network structures and vulnerability, and various other
practical networking applications.Comment: (Review article) 71 pages, 14 figure
Boundary Conditions for Interacting Membranes
We investigate supersymmetric boundary conditions in both the Bagger-Lambert
and the ABJM theories of interacting membranes. We find boundary conditions
associated to the fivebrane, the ninebrane and the M-theory wave. For the ABJM
theory we are able to understand the enhancement of supersymmetry to produce
the (4,4) supersymmetry of the self-dual string. We also include supersymmetric
boundary conditions on the gauge fields that cancel the classical gauge anomaly
of the Chern-Simons terms.Comment: 36 pages, latex, v2 minor typos correcte
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