352 research outputs found
Insulin therapy in people with type 2 diabetes:opportunities and challenges?
Given the continued interest in defining the optimal management of individuals with type 2 diabetes, the Editor of Diabetes Care convened a working party of diabetes specialists to examine this topic in the context of insulin therapy. This was prompted by recent new evidence on the use of insulin in such people. The group was aware of evidence that the benefits of insulin therapy are still usually offered late, and thus the aim of the discussion was how to define the optimal timing and basis for decisions regarding insulin and to apply these concepts in practice. It was noted that recent evidence had built upon that of the previous decades, together confirming the benefits and safety of insulin therapy, albeit with concerns about the potential for hypoglycemia and gain in body weight. Insulin offers a unique ability to control hyperglycemia, being used from the time of diagnosis in some circumstances, when metabolic control is disturbed by medical illness, procedures, or therapy, as well as in the longer term in ambulatory care. For those previously starting insulin, various other forms of therapy can be added later, which offer complementary effects appropriate to individual needs. Here we review current evidence and circumstances in which insulin can be used, consider individualized choices of alternatives and combination regimens, and offer some guidance on personalized targets and tactics for glycemic control in type 2 diabetes
Gravitational waves: search results, data analysis and parameter estimation
The Amaldi 10 Parallel Session C2 on gravitational wave (GW) search results, data analysis and parameter estimation included three lively sessions of lectures by 13 presenters, and 34 posters. The talks and posters covered a huge range of material, including results and analysis techniques for ground-based GW detectors, targeting anticipated signals from different astrophysical sources: compact binary inspiral, merger and ringdown; GW bursts from intermediate mass binary black hole mergers, cosmic string cusps, core-collapse supernovae, and other unmodeled sources; continuous waves from spinning neutron stars; and a stochastic GW background. There was considerable emphasis on Bayesian techniques for estimating the parameters of coalescing compact binary systems from the gravitational waveforms extracted from the data from the advanced detector network. This included methods to distinguish deviations of the signals from what is expected in the context of General Relativity
Trends in epilepsy surgery: stable surgical numbers despite increasing presurgical volumes
Introduction Despite the success of epilepsy surgery, recent reports suggest a decline in surgical numbers. We tested these trends in our cohort to elucidate potential reasons.
Patients and methods Presurgical, surgical and postsurgical data of all patients undergoing presurgical evaluation in between 1990 and 2013 were retrospectively analysed. Patients were grouped according to the underlying pathology.
Results A total of 3060 patients were presurgically studied, and resective surgery was performed in 66.8% (n=2044) of them: medial temporal sclerosis (MTS): n=675, 33.0%; benign tumour (BT): n=408, 20.0%; and focal cortical dysplasia (FCD): n=284, 13.9%. Of these, 1929 patients (94.4%) had a follow-up of 2 years, and 50.8% were completely seizure free (Engel IA). Seizure freedom rate slightly improved over time. Presurgical evaluations continuously increased, whereas surgical interventions did not. Numbers for MTS, BT and temporal lobe resections decreased since 2009. The number of non-lesional patients and the need for intracranial recordings increased. More evaluated patients did not undergo surgery (more than 50% in 2010–2013) because patients were not suitable (mainly due to missing hypothesis: 4.5% in 1990–1993 up to 21.1% in 2010–2013, total 13.4%) or declined from surgery (maximum 21.0% in 2010–2013, total 10.9%). One potential reason may be that increasingly detailed information on chances and risks were given over time.
Conclusions The increasing volume of the presurgical programme largely compensates for decreasing numbers of surgically remediable syndromes and a growing rate of informed choice against epilepsy surgery. Although comprehensive diagnostic evaluation is offered to a larger group of epilepsy patients, surgical numbers remain stable
Role of Phagocytosis in the Pro-Inflammatory Response in LDL-Induced Foam Cell Formation; a Transcriptome Analysis
Excessive accumulation of lipid inclusions in the arterial wall cells (foam cell formation) caused by modified low-density lipoprotein (LDL) is the earliest and most noticeable manifestation of atherosclerosis. The mechanisms of foam cell formation are not fully understood and can involve altered lipid uptake, impaired lipid metabolism, or both. Recently, we have identified the top 10 master regulators that were involved in the accumulation of cholesterol in cultured macrophages induced by the incubation with modified LDL. It was found that most of the identified master regulators were related to the regulation of the inflammatory immune response, but not to lipid metabolism. A possible explanation for this unexpected result is a stimulation of the phagocytic activity of macrophages by modified LDL particle associates that have a relatively large size. In the current study, we investigated gene regulation in macrophages using transcriptome analysis to test the hypothesis that the primary event occurring upon the interaction of modified LDL and macrophages is the stimulation of phagocytosis, which subsequently triggers the pro-inflammatory immune response. We identified genes that were up- or downregulated following the exposure of cultured cells to modified LDL or latex beads (inert phagocytosis stimulators). Most of the identified master regulators were involved in the innate immune response, and some of them were encoding major pro-inflammatory proteins. The obtained results indicated that pro-inflammatory response to phagocytosis stimulation precedes the accumulation of intracellular lipids and possibly contributes to the formation of foam cells. In this way, the currently recognized hypothesis that the accumulation of lipids triggers the pro-inflammatory response was not confirmed. Comparative analysis of master regulators revealed similarities in the genetic regulation of the interaction of macrophages with naturally occurring LDL and desialylated LDL. Oxidized and desialylated LDL affected a different spectrum of genes than naturally occurring LDL. These observations suggest that desialylation is the most important modification of LDL occurring in vivo. Thus, modified LDL caused the gene regulation characteristic of the stimulation of phagocytosis. Additionally, the knock-down effect of five master regulators, such as IL15, EIF2AK3, F2RL1, TSPYL2, and ANXA1, on intracellular lipid accumulation was tested. We knocked down these genes in primary macrophages derived from human monocytes. The addition of atherogenic naturally occurring LDL caused a significant accumulation of cholesterol in the control cells. The knock-down of the EIF2AK3 and IL15 genes completely prevented cholesterol accumulation in cultured macrophages. The knock-down of the ANXA1 gene caused a further decrease in cholesterol content in cultured macrophages. At the same time, knock-down of F2RL1 and TSPYL2 did not cause an effect. The results obtained allowed us to explain in which way the inflammatory response and the accumulation of cholesterol are related confirming our hypothesis of atherogenesis development based on the following viewpoints: LDL particles undergo atherogenic modifications that, in turn, accompanied by the formation of self-associates; large LDL associates stimulate phagocytosis; as a result of phagocytosis stimulation, pro-inflammatory molecules are secreted; these molecules cause or at least contribute to the accumulation of intracellular cholesterol. Therefore, it became obvious that the primary event in this sequence is not the accumulation of cholesterol but an inflammatory response
The Mock LISA Data Challenges: from Challenge 3 to Challenge 4
The Mock LISA Data Challenges are a program to demonstrate LISA data-analysis
capabilities and to encourage their development. Each round of challenges
consists of one or more datasets containing simulated instrument noise and
gravitational waves from sources of undisclosed parameters. Participants
analyze the datasets and report best-fit solutions for the source parameters.
Here we present the results of the third challenge, issued in Apr 2008, which
demonstrated the positive recovery of signals from chirping Galactic binaries,
from spinning supermassive--black-hole binaries (with optimal SNRs between ~ 10
and 2000), from simultaneous extreme-mass-ratio inspirals (SNRs of 10-50), from
cosmic-string-cusp bursts (SNRs of 10-100), and from a relatively loud
isotropic background with Omega_gw(f) ~ 10^-11, slightly below the LISA
instrument noise.Comment: 12 pages, 2 figures, proceedings of the 8th Edoardo Amaldi Conference
on Gravitational Waves, New York, June 21-26, 200
The EBV Immunoevasins vIL-10 and BNLF2a Protect Newly Infected B Cells from Immune Recognition and Elimination
Lifelong persistence of Epstein-Barr virus (EBV) in infected hosts is mainly owed to the virus' pronounced abilities to evade immune responses of its human host. Active immune evasion mechanisms reduce the immunogenicity of infected cells and are known to be of major importance during lytic infection. The EBV genes BCRF1 and BNLF2a encode the viral homologue of IL-10 (vIL-10) and an inhibitor of the transporter associated with antigen processing (TAP), respectively. Both are known immunoevasins in EBV's lytic phase. Here we describe that BCRF1 and BNLF2a are functionally expressed instantly upon infection of primary B cells. Using EBV mutants deficient in BCRF1 and BNLF2a, we show that both factors contribute to evading EBV-specific immune responses during the earliest phase of infection. vIL-10 impairs NK cell mediated killing of infected B cells, interferes with CD4+ T-cell activity, and modulates cytokine responses, while BNLF2a reduces antigen presentation and recognition of newly infected cells by EBV-specific CD8+ T cells. Together, both factors significantly diminish the immunogenicity of EBV-infected cells during the initial, pre-latent phase of infection and may improve the establishment of a latent EBV infection in vivo
ABCA7 p.G215S as potential protective factor for Alzheimer’s disease
Genome-wide association studies (GWASs) have been effective approaches to dissect common genetic variability underlying complex diseases in a systematic and unbiased way. Recently, GWASs have led to the discovery of over 20 susceptibility loci for Alzheimer’s disease (AD).
Despite the evidence showing the contribution of these loci to AD pathogenesis, their genetic architecture has not been extensively investigated, leaving the possibility that low frequency and rare coding variants may also occur and contribute to the risk of disease. We have used exome and genome sequencing data to analyse the single independent and joint effect of rare and low frequency protein coding variants in 9 AD GWAS loci with the strongest effect sizes after APOE (BIN1, CLU, CR1, PICALM, MS4A6A, ABCA7, EPHA1, CD33, CD2AP) in a cohort of 332 sporadic AD cases and 676 elderly controls of British and North American ancestry. We identified coding variability in ABCA7 as contributing to AD risk. This locus harbors a low frequency coding variant (p.G215S, rs72973581, MAF=4.3%) conferring a modest but statistically significant protection against AD (p-value= 6x10-4, OR=0.57, 95% CI 0.41-0.80). Notably, our results are not driven by an enrichment of loss of function variants in ABCA7, recently reported as main pathogenic factor underlying AD risk at this locus. In summary, our study confirms the role of ABCA7 in AD and provide new insights that should address functional studies
The Detectability of Earth's Biosignatures Across Time
Over the past two decades, enormous advances in the detection of exoplanets
have taken place. Currently, we have discovered hundreds of earth-sized
planets, several of them within the habitable zone of their star. In the coming
years, the efforts will concentrate in the characterization of these planets
and their atmospheres to try to detect the presence of biosignatures. However,
even if we discovered a second Earth, it is very unlikely that it would present
a stage of evolution similar to the present-day Earth. Our planet has been far
from static since its formation about 4.5 Ga ago; on the contrary, during this
time, it has undergone multiple changes in it's atmospheric composition, it's
temperature structure, it's continental distribution, and even changes in the
forms of life that inhabit it. All these changes have affected the global
properties of Earth as seen from an astronomical distance. Thus, it is of
interest not only to characterize the observables of the Earth as it is today,
but also at different epochs. Here we review the detectability of the Earth's
globally-averaged properties over time. This includes atmospheric composition
and biosignatures, and surface properties that can be interpreted as sings of
habitability (bioclues). The resulting picture is that truly unambiguous
biosignatures are only detectable for about 1/4 of the Earth's history. The
rest of the time we rely on detectable bioclues that can only establish an
statistical likelihood for the presence of life on a given planet.Comment: To appear in "Handbook of Exoplanets", eds. Deeg, H.J. & Belmonte,
J.A, Springer (2018). arXiv admin note: text overlap with
arXiv:astro-ph/0609398 by other author
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