1,567 research outputs found
Strategies to control therapeutic antibody glycosylation during bioprocessing: synthesis and separation.
Glycosylation can be a critical quality attribute (CQA) in biologic manufacturing. In particular, it has implications on the half-life, immunogenicity and pharmacokinetics of therapeutic monoclonal antibodies (mAbs) and must be closely monitored throughout drug development and manufacturing. To address this, advances have been made primarily in upstream processing, including mammalian cell line engineering to yield more predictably glycosylated mAbs, and the addition of media supplements during fermentation to manipulate the metabolic pathways involved in glycosylation. A more robust approach would be a conjoined upstream-downstream processing strategy. This could include implementing novel downstream technologies, such as the use of Fc gamma-based affinity ligands for the separation of mAb glycovariants. This review highlights the importance of controlling therapeutic antibody glycosylation patterns, the challenges faced in terms of glycosylation during mAb biosimilar development, current efforts both upstream and downstream to control glycosylation and their limitations, and the need for research in the downstream space in order to establish holistic and consistent manufacturing processes for the production of antibody therapies. This article is protected by copyright. All rights reserved
The association between pre-hospital antibiotic therapy and subsequent in-hospital mortality in adults presenting with community-acquired pneumonia: an observational study
Background The majority of patients with community acquired-pneumonia (CAP) are treated in primary care and the mortality in this group is very low. However, a small but significant proportion of patients who begin treatment in the community subsequently require admission due to symptomatic deterioration. This study compared patients who received community antibiotics prior to admission to those who had not, and looked for associations with clinical outcomes. Methods This study analysed the Advancing Quality (AQ) Pneumonia database of patients admitted with CAP to 9 acute hospitals in the northwest of England over a 12-month period. Results There were 6348 subjects (mean age 72 [SD 16] years; gender ratio 1:1) admitted with CAP, of whom 17% had been pre-treated with antibiotics. The in-hospital mortality was 18.6% for the pre-treatment group compared to 13.2% in the “antibiotic naïve” group (p < 0.001). On multivariate analysis, age, male gender and antibiotic pre-treatment were predictors of in-hospital mortality along with a history of cerebrovascular accident, congestive cardiac failure, dementia, renal disease and cancer. After adjustment for CURB-65 score, age, co-morbidities and pre-treatment with antibiotics remained as independent risk factors for in-hospital mortality (OR 1.43, 95% CI 1.19–1.71). Conclusion CAP patients admitted to hospital were more likely to die during admission if they had received antibiotics for the same illness pre-admission. Future studies should endeavor to determine the mechanisms underlying this association, such as microbiological factors and the role of comorbidities. Patients hospitalized with CAP despite prior antibiotic treatment in the community require close monitoring
The conceptualisation and measurement of DSM-5 Internet Gaming Disorder: the development of the IGD-20 Test
Background: Over the last decade, there has been growing concern about ‘gaming addiction’ and its widely documented detrimental impacts on a minority of individuals that play excessively. The latest (fifth) edition of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM-5) included nine criteria for the potential diagnosis of Internet Gaming Disorder (IGD) and noted that it was a condition that warranted further empirical study. Aim: The main aim of this study was to develop a valid and reliable standardised psychometrically robust tool in addition to providing empirically supported cut-off points. Methods: A sample of 1003 gamers (85.2% males; mean age 26 years) from 57 different countries were recruited via online gaming forums. Validity was assessed by confirmatory factor analysis (CFA), criterion-related validity, and concurrent validity. Latent profile analysis was also carried to distinguish disordered gamers from non-disordered gamers. Sensitivity and specificity analyses were performed to determine an empirical cut-off for the test. Results: The CFA confirmed the viability of IGD-20 Test with a six-factor structure (salience, mood modification, tolerance, withdrawal, conflict and relapse) for the assessment of IGD according to the nine criteria from DSM-5. The IGD-20 Test proved to be valid and reliable. According to the latent profile analysis, 5.3% of the total participants were classed as disordered gamers. Additionally, an optimal empirical cut-off of 71 points (out of 100) seemed to be adequate according to the sensitivity and specificity analyses carried
On Inflation with Non-minimal Coupling
A simple realization of inflation consists of adding the following operators
to the Einstein-Hilbert action: (partial phi)^2, lambda phi^4, and xi phi^2 R,
with xi a large non-minimal coupling. Recently there has been much discussion
as to whether such theories make sense quantum mechanically and if the inflaton
phi can also be the Standard Model Higgs. In this note we answer these
questions. Firstly, for a single scalar phi, we show that the quantum field
theory is well behaved in the pure gravity and kinetic sectors, since the
quantum generated corrections are small. However, the theory likely breaks down
at ~ m_pl / xi due to scattering provided by the self-interacting potential
lambda phi^4. Secondly, we show that the theory changes for multiple scalars
phi with non-minimal coupling xi phi dot phi R, since this introduces
qualitatively new interactions which manifestly generate large quantum
corrections even in the gravity and kinetic sectors, spoiling the theory for
energies > m_pl / xi. Since the Higgs doublet of the Standard Model includes
the Higgs boson and 3 Goldstone bosons, it falls into the latter category and
therefore its validity is manifestly spoiled. We show that these conclusions
hold in both the Jordan and Einstein frames and describe an intuitive analogy
in the form of the pion Lagrangian. We also examine the recent claim that
curvature-squared inflation models fail quantum mechanically. Our work appears
to go beyond the recent discussions.Comment: 14 pages, 2 figures. Version 2: Clarified findings and improved
wording. Elaborated important sections and removed an unnecessary section.
Added references. Version 3: Updated towards JHEP version. Version 4: Final
JHEP versio
Microdeletion del(22)(q12.2) encompassing the facial development-associated gene, MN1 (meningioma 1) in a child with Pierre-Robin sequence (including cleft palate) and neurofibromatosis 2 (NF2): a case report and review of the literature
<p>Abstract</p> <p>Background</p> <p>Pierre-Robin sequence (PRS) is defined by micro- and/or retrognathia, glossoptosis and cleft soft palate, either caused by deformational defect or part of a malformation syndrome. Neurofibromatosis type 2 (NF2) is an autosomal dominant syndrome caused by mutations in the <it>NF2 </it>gene on chromosome 22q12.2. NF2 is characterized by bilateral vestibular schwannomas, spinal cord schwannomas, meningiomas and ependymomas, and juvenile cataracts. To date, NF2 and PRS have not been described together in the same patient.</p> <p>Case presentation</p> <p>We report a female with PRS (micrognathia, cleft palate), microcephaly, ocular hypertelorism, mental retardation and bilateral hearing loss, who at age 15 was also diagnosed with severe NF2 (bilateral cerebellopontine schwannomas and multiple extramedullary/intradural spine tumors). This is the first published report of an individual with both diagnosed PRS and NF2. High resolution karyotype revealed 46, XX, del(22)(q12.1q12.3), FISH confirmed a deletion encompassing <it>NF2</it>, and chromosomal microarray identified a 3,693 kb deletion encompassing multiple genes including <it>NF2 </it>and <it>MN1 </it>(meningioma 1).</p> <p>Five additional patients with craniofacial dysmorphism and deletion in chromosome 22-adjacent-to or containing <it>NF2 </it>were identified in PubMed and the DECIPHER clinical chromosomal database. Their shared chromosomal deletion encompassed <it>MN1</it>, <it>PITPNB </it>and <it>TTC28</it>. <it>MN1</it>, initially cloned from a patient with meningioma, is an oncogene in murine hematopoiesis and participates as a fusion gene (<it>TEL</it>/<it>MN1</it>) in human myeloid leukemias. Interestingly, <it>Mn1</it>-haploinsufficient mice have abnormal skull development and secondary cleft palate. Additionally, <it>Mn1 </it>regulates maturation and function of calvarial osteoblasts and is an upstream regulator of <it>Tbx22</it>, a gene associated with murine and human cleft palate. This suggests that deletion of <it>MN1 </it>in the six patients we describe may be causally linked to their cleft palates and/or craniofacial abnormalities.</p> <p>Conclusions</p> <p>Thus, our report describes a <it>NF2</it>-adjacent chromosome 22q12.2 deletion syndrome and is the first to report association of <it>MN1 </it>deletion with abnormal craniofacial development and/or cleft palate in humans.</p
Pydna: a simulation and documentation tool for DNA assembly strategies using python
Background: Recent advances in synthetic biology have provided tools to efficiently construct complex DNA molecules which are an important part of many molecular biology and biotechnology projects. The planning of such constructs has traditionally been done manually using a DNA sequence editor which becomes error-prone as scale and complexity of the construction increase. A human-readable formal description of cloning and assembly strategies, which also allows for automatic computer simulation and verification, would therefore be a valuable tool.Results: We have developed pydna, an extensible, free and open source Python library for simulating basic molecular biology DNA unit operations such as restriction digestion, ligation, PCR, primer design, Gibson assembly and homologous recombination. A cloning strategy expressed as a pydna script provides a description that is complete, unambiguous and stable. Execution of the script automatically yields the sequence of the final molecule(s) and that of any intermediate constructs. Pydna has been designed to be understandable for biologists with limited programming skills by providing interfaces that are semantically similar to the description of molecular biology unit operations found in literature.Conclusions: Pydna simplifies both the planning and sharing of cloning strategies and is especially useful for complex or combinatorial DNA molecule construction. An important difference compared to existing tools with similar goals is the use of Python instead of a specifically constructed language, providing a simulation environment that is more flexible and extensible by the user.Thanks to Dr. Aric Hagberg Los Alamos National Laboratory, U.S.A and Sergio Simoes, Universidade de Sao Paulo, Brasil for help with NetworkX and graph theory in general. Thanks to Henrik Bengtsson, Dept of Epidemiology & Biostatistics, University of California San Francisco, U.S.A. for critical reading of the manuscript. Thanks to the 2013 Bioinformatics 6605 N4 students A. Coelho, A. Faria, A. Neves D. Yelshyna and E. Costa for testing. This work was supported by the Fundacao para a Ciencia e Tecnologia (FCT) [PTDC/AAC-AMB/120940/2010, EXPL/BBB-BIO/1772/2013]; and the FEDER POFC-COMPETE [PEst-C/BIA/UI4050/2011]. FA and GR were supported by FCT fellowships [SFRH/BD/80934/2011 and SFRH/BD/42565/2007, respectively].info:eu-repo/semantics/publishedVersio
The impact of predation by marine mammals on Patagonian toothfish longline fisheries
Predatory interaction of marine mammals with longline fisheries is observed globally, leading to partial or complete loss of the catch and in some parts of the world to considerable financial loss. Depredation can also create additional unrecorded fishing mortality of a stock and has the potential to introduce bias to stock assessments. Here we aim to characterise depredation in the Patagonian toothfish (Dissostichus eleginoides) fishery around South Georgia focusing on the spatio-temporal component of these interactions. Antarctic fur seals (Arctocephalus gazella), sperm whales (Physeter macrocephalus), and orcas (Orcinus orca) frequently feed on fish hooked on longlines around South Georgia. A third of longlines encounter sperm whales, but loss of catch due to sperm whales is insignificant when compared to that due to orcas, which interact with only 5% of longlines but can take more than half of the catch in some cases. Orca depredation around South Georgia is spatially limited and focused in areas of putative migration routes, and the impact is compounded as a result of the fishery also concentrating in those areas at those times. Understanding the seasonal behaviour of orcas and the spatial and temporal distribution of “depredation hot spots” can reduce marine mammal interactions, will improve assessment and management of the stock and contribute to increased operational efficiency of the fishery. Such information is valuable in the effort to resolve the human-mammal conflict for resources
Impact of generic alendronate cost on the cost-effectiveness of osteoporosis screening and treatment
Introduction: Since alendronate became available in generic form in the Unites States in 2008, its price has been decreasing. The objective of this study was to investigate the impact of alendronate cost on the cost-effectiveness of osteoporosis screening and treatment in postmenopausal women. Methods: Microsimulation cost-effectiveness model of osteoporosis screening and treatment for U.S. women age 65 and older. We assumed screening initiation at age 65 with central dual-energy x-ray absorptiometry (DXA), and alendronate treatment for individuals with osteoporosis; with a comparator of "no screening" and treatment only after fracture occurrence. We evaluated annual alendronate costs of 800; outcome measures included fractures; nursing home admission; medication adverse events; death; costs; quality-adjusted life-years (QALYs); and incremental cost-effectiveness ratios (ICERs) in 2010 U.S. dollars per QALY gained. A lifetime time horizon was used, and direct costs were included. Base-case and sensitivity analyses were performed. Results: Base-case analysis results showed that at annual alendronate costs of 400 through 714 per QALY gained through 50,000/QALY at all alendronate costs evaluated. Conclusions: Osteoporosis screening followed by alendronate treatment is effective and highly cost-effective for postmenopausal women across a range of alendronate costs, and may be cost-saving at annual alendronate costs of $200 or less. © 2012 Nayak et al
A Vast Thin Plane of Co-rotating Dwarf Galaxies Orbiting the Andromeda Galaxy
Dwarf satellite galaxies are thought to be the remnants of the population of
primordial structures that coalesced to form giant galaxies like the Milky Way.
An early analysis noted that dwarf galaxies may not be isotropically
distributed around our Galaxy, as several are correlated with streams of HI
emission, and possibly form co-planar groups. These suspicions are supported by
recent analyses, and it has been claimed that the apparently planar
distribution of satellites is not predicted within standard cosmology, and
cannot simply represent a memory of past coherent accretion. However, other
studies dispute this conclusion. Here we report the existence (99.998%
significance) of a planar sub-group of satellites in the Andromeda galaxy,
comprising approximately 50% of the population. The structure is vast: at least
400 kpc in diameter, but also extremely thin, with a perpendicular scatter
<14.1 kpc (99% confidence). Radial velocity measurements reveal that the
satellites in this structure have the same sense of rotation about their host.
This finding shows conclusively that substantial numbers of dwarf satellite
galaxies share the same dynamical orbital properties and direction of angular
momentum, a new insight for our understanding of the origin of these most dark
matter dominated of galaxies. Intriguingly, the plane we identify is
approximately aligned with the pole of the Milky Way's disk and is co-planar
with the Milky Way to Andromeda position vector. The existence of such
extensive coherent kinematic structures within the halos of massive galaxies is
a fact that must be explained within the framework of galaxy formation and
cosmology.Comment: Published in the 3rd Jan 2013 issue of Nature. 19 pages, 4 figures, 1
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