The natural history of Precambrian life is still unknown because of the rarity of microbial fossils and biomarkers. However, the composition of modern-day genomes may bear imprints of ancient ...biogeochemical events. Here we use an explicit model of macroevolution including gene birth, transfer, duplication and loss events to map the evolutionary history of 3,983 gene families across the three domains of life onto a geological timeline. Surprisingly, we find that a brief period of genetic innovation during the Archaean eon, which coincides with a rapid diversification of bacterial lineages, gave rise to 27% of major modern gene families. A functional analysis of genes born during this Archaean expansion reveals that they are likely to be involved in electron-transport and respiratory pathways. Genes arising after this expansion show increasing use of molecular oxygen (P = 3.4 × 10(-8)) and redox-sensitive transition metals and compounds, which is consistent with an increasingly oxygenating biosphere.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Clinical oncology is being revolutionized by the increasing use of molecularly targeted therapies. This paradigm holds great promise for improving cancer treatment; however, allocating specific ...therapies to the patients who are most likely to derive a durable benefit continues to represent a considerable challenge. Evidence continues to emerge that cancers are characterized by extensive intratumour genetic heterogeneity, and that patients being considered for treatment with a targeted agent might, therefore, already possess resistance to the drug in a minority of cells. Indeed, multiple examples of pre-existing subclonal resistance mutations to various molecularly targeted agents have been described, which we review herein. Early detection of pre-existing or emerging drug resistance could enable more personalized use of targeted cancer therapy, as patients could be stratified to receive the therapies that are most likely to be effective. We consider how monitoring of drug resistance could be incorporated into clinical practice to optimize the use of targeted therapies in individual patients.
This phase 3 trial evaluated the safety and efficacy of inclisiran, a small interfering RNA that inhibits hepatic PCSK9 synthesis, in 482 adults with heterozygous familial hypercholesterolemia, who ...received subcutaneous injections of inclisiran or placebo on days 1, 90, 270, and 450. Changes in cholesterol were assessed up to day 540.
Most discoveries in materials science have been made empirically, typically through one-variable-at-a-time (Edisonian) experimentation. The characteristics of materials-based systems are, however, ...neither simple nor uncorrelated. In a device such as an organic photovoltaic, for example, the level of complexity is high due to the sheer number of components and processing conditions, and thus, changing one variable can have multiple unforeseen effects due to their interconnectivity. Design of Experiments (DoE) is ideally suited for such multivariable analyses: by planning one’s experiments as per the principles of DoE, one can test and optimize several variables simultaneously, thus accelerating the process of discovery and optimization while saving time and precious laboratory resources. When combined with machine learning, the consideration of one’s data in this manner provides a different perspective for optimization and discovery, akin to climbing out of a narrow valley of serial (one-variable-at-a-time) experimentation, to a mountain ridge with a 360° view in all directions.
The magnitude of effect of sodium-glucose cotransporter-2 inhibitors (SGLT2i) on specific cardiovascular and renal outcomes and whether heterogeneity is based on key baseline characteristics remains ...undefined.
We did a systematic review and meta-analysis of randomised, placebo-controlled, cardiovascular outcome trials of SGLT2i in patients with type 2 diabetes. We searched PubMed and Embase for trials published up to Sept 24, 2018. Data search and extraction were completed with a standardised data form and any discrepancies were resolved by consensus. Efficacy outcomes included major adverse cardiovascular events (myocardial infarction, stroke, or cardiovascular death), the composite of cardiovascular death or hospitalisation for heart failure, and progression of renal disease. Hazard ratios (HRs) with 95% CIs were pooled across trials, and efficacy outcomes were stratified by baseline presence of atherosclerotic cardiovascular disease, heart failure, and degree of renal function.
We included data from three identified trials and 34 322 patients (60·2% with established atherosclerotic cardiovascular disease), with 3342 major adverse cardiovascular events, 2028 cardiovascular deaths or hospitalisation sfor heart failure events, and 766 renal composite outcomes. SGLT2i reduced major adverse cardiovascular events by 11% (HR 0·89 95% CI 0·83–0·96, p=0·0014), with benefit only seen in patients with atherosclerotic cardiovascular disease (0·86 0·80–0·93) and not in those without (1·00 0·87–1·16, p for interaction=0·0501). SGLT2i reduced the risk of cardiovascular death or hospitalisation for heart failure by 23% (0·77 0·71–0·84, p<0·0001), with a similar benefit in patients with and without atherosclerotic cardiovascular disease and with and without a history of heart failure. SGLT2i reduced the risk of progression of renal disease by 45% (0·55 0·48–0·64, p<0·0001), with a similar benefit in those with and without atherosclerotic cardiovascular disease. The magnitude of benefit of SGLT2i varied with baseline renal function, with greater reductions in hospitalisations for heart failure (p for interaction=0·0073) and lesser reductions in progression of renal disease (p for interaction=0·0258) in patients with more severe kidney disease at baseline.
SGLT2i have moderate benefits on atherosclerotic major adverse cardiovascular events that seem confined to patients with established atherosclerotic cardiovascular disease. However, they have robust benefits on reducing hospitalisation for heart failure and progression of renal disease regardless of existing atherosclerotic cardiovascular disease or a history of heart failure.
None.
Managing excess nutrients remains a major obstacle to improving ecosystem service benefits of urban waters. To inform more ecologically based landscape nutrient management, we compared watershed ...inputs, outputs, and retention for nitrogen (N) and phosphorus (P) in seven subwatersheds of the Mississippi River in St. Paul, Minnesota. Lawn fertilizer and pet waste dominated N and P inputs, respectively, underscoring the importance of household actions in influencing urban watershed nutrient budgets. Watersheds retained only 22% of net P inputs versus 80% of net N inputs (watershed area-weighted averages, where net inputs equal inputs minus biomass removal) despite relatively low P inputs. In contrast to many nonurban watersheds that exhibit high P retention, these urban watersheds have high street density that enhanced transport of P-rich materials from landscapes to stormwater. High P exports in storm drainage networks and yard waste resulted in net P losses in some watersheds. Comparisons of the N/P stoichiometry of net inputs versus storm drain exports implicated denitrification or leaching to groundwater as a likely fate for retained N. Thus, these urban watersheds exported high quantities of N and P, but via contrasting pathways: P was exported primarily via stormwater runoff, contributing to surface water degradation, whereas N losses additionally contribute to groundwater pollution. Consequently, N management and P management require different strategies, with N management focusing on reducing watershed inputs and P management also focusing on reducing P movement from vegetated landscapes to streets and storm drains.
Drusenoid pigment epithelium detachment (DPED) is a known precursor to geographic atrophy in age-related macular degeneration (AMD). We sought histologic correlates for spectral-domain (SD) optical ...coherence tomography (OCT) signatures in DPED and determined the frequency and origin of these OCT signatures in a clinical cohort of DPED eyes.
Laboratory imaging and histologic comparison, and retrospective, observational cohort study.
Four donor eyes with histopathologic diagnosis of AMD (2 with nonneovascular DPED and 2 with neovascular pigment epithelium detachment PED) and 49 eyes of 33 clinic patients with nonneovascular DPED more than 2 mm in diameter.
Donor eyes underwent multimodal ex vivo imaging, including SD OCT, then processing for high-resolution histologic analysis. All clinic patients underwent SD OCT, near-infrared reflectance, and color photography.
Histologic correlates for SD OCT signatures in DPED, estimate of coverage by different retinal pigment epithelium (RPE) phenotypes in the DPED surface; frequency and origin of histologically verified SD OCT signatures in a clinical cohort of DPED eyes, and comparisons of histologic features between neovascular PED and DPED resulting from AMD.
Intraretinal and subretinal hyperreflective foci as seen on SD OCT correlated to RPE cells on histologic examination. Hypertransmission of light below the RPE-basal lamina band correlated with dissociated RPE. Subretinal hyperreflective material resulting from acquired vitelliform lesions corresponded to regions of apically expelled RPE organelles. In the clinical cohort, all histologically verified reflectivity signatures were visible and quantifiable. The appearance of intraretinal hyperreflective foci was preceded by thickening of the RPE-basal lamina band. Compared with PEDs associated with neovascular AMD, DPEDs had different crystallization patterns, no lipid-filled cells, and thinner basal laminar deposits.
Multiple RPE fates in AMD, including intraretinal cells that are highly prognostic for progression, can be followed and quantified reliably using eye-tracked serial SD OCT. This information may be particularly useful for obtaining an accurate timeline of incipient geographic atrophy in clinic populations and for quantifying anatomic end points and response to therapy in AMD clinical trials.