Publications by authors named "Mast C"

Background: Treating obesity may be a pathway to prevent and control hypertension. In the SURMOUNT-1 trial in people with obesity or overweight with weight-related complications, 72-week tirzepatide treatment led to clinically meaningful body weight and blood pressure reduction. Post hoc analyses were conducted to further explore the effects of tirzepatide on the pattern of blood pressure reduction and whether the effects were consistent across various subgroups.

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  • Biopolymer building blocks are essential for the origins of life, but their formation typically requires rare feedstocks and complex purification processes.
  • A new study suggests that heat flow through thin geological cracks can effectively separate over 50 prebiotically relevant compounds from complex mixtures, enhancing their concentration.
  • The method significantly boosts reaction yields, as shown by the increased dimerization of glycine when trimetaphosphate is selectively purified, highlighting the potential role of geological processes in prebiotic chemistry.
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  • - Templated ligation is an efficient method for replicating long RNA strands using a prebiotically available activation, specifically the 2',3'-cyclic phosphate, which forms during RNA breakdown.
  • - Research shows that this ligation process can occur in simple conditions (low-salt, alkaline pH, and moderate temperatures) without needing additional catalysts, leading to a 50% increase in canonical linkages compared to past studies.
  • - The reaction is sequence-specific with high fidelity rates, enabling the successful creation of longer RNA strands, which may indicate how ribozymes could have assembled on early Earth.
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The emergence of functional oligonucleotides on early Earth required a molecular selection mechanism to screen for specific sequences with prebiotic functions. Cyclic processes such as daily temperature oscillations were ubiquitous in this environment and could trigger oligonucleotide phase separation. Here, we propose sequence selection based on phase separation cycles realized through sedimentation in a system subjected to the feeding of oligonucleotides.

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We measure the thermophoresis of polysterene beads over a wide range of temperature gradients and find a pronounced nonlinear phoretic characteristic. The transition to the nonlinear behavior is marked by a drastic slowing down of thermophoretic motion and is characterized by a Péclet number of order unity as corroborated for different particle sizes and salt concentrations. The data follow a single master curve covering the entire nonlinear regime for all system parameters upon proper rescaling of the temperature gradients with the Péclet number.

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Understanding the sequence-dependent DNA damage formation requires probing a complete pool of sequences over a wide dose range of the damage-causing exposure. We used high throughput sequencing to simultaneously obtain the dose dependence and quantum yields for oligonucleotide damages for all possible 4096 DNA sequences with hexamer length. We exposed the DNA to ultraviolet radiation at 266 nm and doses of up to 500 absorbed photons per base.

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Life is based on informational polymers such as DNA or RNA. For their polymerization, high concentrations of complex monomer building blocks are required. Therefore, the dilution by diffusion poses a major problem before early life could establish a non-equilibrium of compartmentalization.

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  • * Researchers constructed lipid-stabilized foams under thermal gradients to enhance RNA accumulation and oligomerization, simulating early life conditions through alternating wet and dry states.
  • * Myristic acid was identified as an effective stabilizer, and the resulting foams facilitated molecular localization and the formation of RNA aggregates, indicating a promising avenue for studying early molecular evolution.
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Key requirements for the first cells on Earth include the ability to compartmentalize and evolve. Compartmentalization spatially localizes biomolecules from a dilute pool and an evolving cell, which, as it grows and divides, permits mixing and propagation of information to daughter cells. Complex coacervate microdroplets are excellent candidates as primordial cells with the ability to partition and concentrate molecules into their core and support primitive and complex biochemical reactions.

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Catalytic nucleic acids, such as ribozymes, are central to a variety of origin-of-life scenarios. Typically, they require elevated magnesium concentrations for folding and activity, but their function can be inhibited by high concentrations of monovalent salts. Here we show that geologically plausible high-sodium, low-magnesium solutions derived from leaching basalt (rock and remelted glass) inhibit ribozyme catalysis, but that this activity can be rescued by selective magnesium up-concentration by heat flow across rock fissures.

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The RNA world scenario posits replication by RNA polymerases. On early Earth, a geophysical setting is required to separate hybridized strands after their replication and to localize them against diffusion. We present a pointed heat source that drives exponential, RNA-catalyzed amplification of short RNA with high efficiency in a confined chamber.

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  • Non-equilibrium conditions were essential for the early assembly of informational polymers like RNA by providing a stable environment for their formation and enrichment.
  • Gas bubbles in thermally varying water, similar to conditions on early Earth, facilitate the continuous accumulation of prebiotic molecules and enhance their chemical activities.
  • These processes lead to key developments such as RNA phosphorylation, increased ribozyme activity, hydrogel formation, crystallization, and the creation of protective vesicle aggregates, all occurring in under 30 minutes, indicating a feasible pathway for the onset of molecular evolution.
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To understand the emergence of life, a better understanding of the physical chemistry of primordial non-equilibrium conditions is essential. Significant salt concentrations are required for the catalytic function of RNA. The separation of oligonucleotides into single strands is a difficult problem as the hydrolysis of RNA becomes a limiting factor at high temperatures.

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The optimisation of nutritional support for the growing number of older individuals does not usually take into account medication. Paracetamol (acetaminophen; APAP) is the first intention treatment of chronic pain that is highly prevalent and persistent in the elderly. Detoxification of APAP occurs in the liver and utilises sulfate and glutathione (GSH), both of which are issued from cysteine (Cys), a conditionally indispensable amino acid.

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Proton gradients are essential for biological systems. They not only drive the synthesis of ATP, but initiate molecule degradation and recycling inside lysosomes. However, the high mobility and permeability of protons through membranes make pH gradients very hard to sustain in vitro.

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  • Cysteine (Cys) is vital for detoxifying paracetamol and may help combat sarcopenia, especially in older rats exposed to repeated doses of the drug.
  • A study on 21.5-month-old Wistar rats showed that adding dietary Cys during paracetamol treatment improved the balance of Cys and glutathione (GSH), preventing liver damage and helping to maintain muscle mass.
  • Cys supplementation led to significant reductions in liver mass increase and blood GSH concentration while enhancing muscle growth, highlighting its protective role against the negative effects of paracetamol in aging.
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The availability of all amino acids is of prime importance to prevent the ageing-associated decrease in skeletal muscle mass i.e. sarcopenia.

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DNA phase transitions are often induced by the addition of condensation agents or by dry concentration. Herein, we show that the non-equilibrium setting of a moderate heat flow across a water-filled chamber separates and gelates DNA strands with single-base resolution. A dilute mix of DNA with two slightly different gel-forming sequences separates into sequence-pure hydrogels under constant physiological solvent conditions.

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Unlabelled: Liver protein can be altered under paracetamol (APAP) treatment. APAP-protein adducts and other protein modifications (oxidation/nitration, expression) play a role in hepatotoxicity induced by acute overdoses, but it is unknown whether liver protein modifications occur during long-term treatment with non-toxic doses of APAP. We quantified APAP-protein adducts and assessed other protein modifications in the liver from rats under chronic (17 days) treatment with two APAP doses (0.

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The use of glutathione (GSH) and sulfate for the detoxification of paracetamol (acetaminophen, APAP) could occur at the expense of the physiological uses of cysteine (Cys). Indeed GSH and sulfate both originate from Cys. Significant APAP-induced Cys loss could generate alterations in GSH and protein metabolisms leading to muscle wasting.

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Both solid and hematologic malignancies may be complicated by coagulopathies. Disseminated intravascular coagulation (DIC) in the presence of pancreatic cancer is generally unrecognized and may have fatal consequences. The diagnosis of DIC in a patient with advanced cancer is a poor prognostic indicator.

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Recent progress in the synthesis of nucleotides from prebiotically plausible precursors has opened up new ways to explain the origin of genetic matter. Mechanisms for the polymerization of nucleotides without the help of catalysts are, however, rare. Complementary to the experiments done by Costanzo et al.

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For the emergence of early life, the formation of biopolymers such as RNA is essential. However, the addition of nucleotide monomers to existing oligonucleotides requires millimolar concentrations. Even in such optimistic settings, no polymerization of RNA longer than about 20 bases could be demonstrated.

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Objective: Certain eligibility criteria for Phase 1 cancer clinical trials may impede successful patient enrollment onto a study. We evaluated patient-specific or study-specific reasons for screen failures on Phase 1 oncology clinical trials and discuss factors which may inhibit subject enrollment.

Methods: Thirty-eight Phase 1 clinical trials for solid tumors meeting eligibility criteria and opened for enrollment between February 2006 and February 2011 at one oncology Phase 1 program were examined.

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