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At least 19 recordsLinked to original sources

Examining Behavioral Interventions for Infancy and Early Toddlerhood: A Systematic Review of Intervention Effects, Parameters, and Participants.

Rapid advancement is paving the way to identify children who would likely benefit from early intervention during the first years of life, prior to the onset of significant delays in development. With the widely acknowledged benefits of early intervention, key questions arise: Does behavioral intervention targeted to infancy and early toddlerhood improve developmental outcomes? What procedures might be used, and under what circumstances? Who do these interventions work for? The current review comprehensively examined the literature on behavioral interventions based in operant learning, focused on key developmental areas with children in the first two years of life. We located and synthesized 69 studies with unique participant cohorts that included 1735 children. The search revealed many studies focused on the first year of life, of which a large proportion investigated approaches to increase communication. We provide implications, limitations, and future directions on how behavioral interventions for infants and young toddlers can inform current practice and future intervention research this population.

Humans

Microtubule posttranslational modifications provide unique recognition patterns for associated proteins.

Microtubules are key components of the eukaryotic cytoskeleton involved in vital functions in virtually every cell. Among the emerging molecular mechanisms to adapt microtubules to their diverse functions is the biochemical diversification of tubulin molecules by posttranslational modifications (PTMs) and differential gene expression, a concept known as the 'tubulin code'. A key question remains whether the tubulin code has the potential to selectively control microtubule interactions of different microtubule-associated proteins (MAPs) to act as a specific signalling system. To answer this question, we used a medium-throughput in vitro approach to screen 46 proteins for their binding preferences to microtubules with altered PTM or isotype composition. We demonstrate that subsets of these MAPs have unique sensitivities to PTMs, while other proteins are not affected. As a result, PTMs, or combinations of them, differentially attract or repulse individual MAPs to microtubules. Our findings offer mechanistic proof for a key hypothesis of the tubulin code-the capacity to selectively and differentially regulate MAP-microtubule interactions.

Journal Article

Emerging trends in genome editing of wild animals.

Globally, nearly one million species are currently threatened with extinction, highlighting the need for more efficient solutions to biological conservation. Genome editing, which allows for faster and more precise changes in genomes, is a promising technique for boosting populations through facilitated adaptation, management of invasive or pathogenic populations, and potentially even facilitating the revival of extinct species. These approaches belong to a new field of research termed conservation biotechnology, which places a great responsibility on researchers and decision makers to ensure sustainability. In this paper, we have mapped the emerging trends in genome editing of wild animals. Current projects primarily focus on population control and de-extinction, with fewer initiatives aimed at preserving threatened species. We then explore four critical dimensions of conservation biotechnology: the technology itself, new perspectives on conservation practices, research organization, and governance and policy. Despite its potential, key questions remain-particularly whether genome editing can increase genetic diversity without causing unintended non-target impacts. Genome editing also provokes new perspectives on conservation practices where ecosystem-wide impact assessment, case-by-case evaluations, and post-release monitoring needs to be prioritized. Furthermore, conservation biotechnology is heavily funded through private funding showing varying stakeholder interest, which can lead to untraditional and less transparent research processes. Stakeholders, including local and indigenous people, are only to a certain degree involved, which may weaken inclusion of local knowledge and monitoring efforts. Finally, concerning governance and policy, there is an urgent need to develop more adequate regulation of conservation biotechnology, as environmental release of genome-edited animals challenges definitions and guidelines in current nature protection laws and GMO regulations. Based on our analysis, we outline key points for further investigation toward a more sustainable approach to conservation biotechnology.

Animals

Single-cell RNA sequencing of peripheral blood defines two immunological subtypes of Sjögren's disease distinguished by anti-SSA antibodies and aberrant B cell populations.

OBJECTIVES: Sjögren's disease (SjD) is a heterogeneous autoimmune disorder characterized by substantial clinical and molecular diversity. This heterogeneity raises key questions regarding the existence of distinct pathogenic mechanisms underlying disease subtypes. The objective of this study was to comprehensively characterize peripheral immune cell states associated with SjD and to identify features that could enable better patient stratification for targeted treatments. METHODS: We performed single-cell RNA sequencing with surface protein profiling on 1.5 million peripheral blood mononuclear cells (PBMCs) from 333 participants. Individuals were stratified by SjD diagnosis and anti-SSA status to enable comparative analyses between disease subgroups and controls. RESULTS: Our analysis identified two immunological endotypes of SjD, with SSA-positive participants exhibiting a dominant and persistent IFN-I signature that was also associated with altered immune cell composition. Transitional B cells were particularly affected, displaying altered developmental states, reduced BCR diversity, shorter CDR3 regions, and increased predicted interactions with activated immune cell populations, findings consistent with perturbations of early B-cell selection processes. By contrast, SSA-negative SjD participants exhibited limited transcriptional differences compared with symptomatic non-SjD controls, highlighting substantial biological heterogeneity within SjD. CONCLUSIONS: These findings support a two-disease model of SjD and highlight transitional B cells as both a key biomarker and a therapeutic target.

Journal Article

Degradation of ribonucleic acid by immobilized ribonuclease.

An immobilized enzyme (pancreatic ribonuclease bound to porous titania) was investigated for the degradation of purified yeast ribonucleic acid as a substrate. The immobilized enzyme is active and stable in the pH range 4--8. Dependence of enzymatic activity on ionic strength, pH, temperature, fluid flow rate, and substrate concentration were investigated. A cumulative fluid residence time of 6 sec is sufficient for 50% substrate conversion at 25 degrees C and pH 7.0. The critical flow rate (i.e., the fluid flow rate necessary to remove film diffusion resistance) approximately doubles with each 10 degree C rise in reaction temperature. The critical flow rates obtained in this study are about 40 times greater than those obtained for a similar study on immobilized glucose oxidase. Arrhenius plots gave activation energies of -9.6 and -7.1 kcal/g mol at pH 4.6 and 7.0, respectively. The work reported herein is a bench-scale investigation of an immobilized enzyme with primary emphasis on the mass transfer and kinetic characteristics of the system. The rapid reaction rates obtainable at relatively low temperatures offer a potential alternative method of purifying yeast single cell protein (SCP) with miminum loss of desired protein. The key questions are how such a system would react in a yeast homogenate, what conditions in such a system must be controlled, and what type of immobilized reactor should be utilized, if such further work continued to show promise.

Ceramics

Chronotherapy with immune checkpoint inhibitors: The knowns, the unknowns, and the contested.

Emerging data indicate that immune checkpoint inhibitors can exhibit time-of-day-dependent effects in pre-clinical models. Furthermore, multiple retrospective clinical trials associate earlier anti-tumor treatment timing with improved outcomes. However, key questions remain regarding the reproducibility of these findings, the underlying mechanisms, and their clinical implications. This commentary discusses these open questions and provides an outlook on the field.

Journal Article

289th ENMC international workshop: assessing and managing emerging AAV related toxicities after gene therapy for neuromuscular disorders, 26 - 28 September 2025, Hoofddorp, The Netherlands.

Adeno-associated virus (AAV) mediated gene therapies has emerged as a potentially transformative treatment approaches for neuromuscular disorders, with two FDA-approved products now in widespread clinical use: onasemnogene abeparvovec (Zolgensma) for spinal muscular atrophy and delandistrogene moxeparvovec-rokl (Elevidys) for Duchenne Muscular Dystrophy. However, severe and occasionally fatal adverse events affecting vital organs, including the blood, liver, muscle, and heart, have emerged in both clinical trials and real-world post marketing settings. The 289th European NeuroMuscular Centre (ENMC) workshop convened 38 participants from patient advocacy groups, industry, and preclinical and clinical research groups to collaboratively review these toxicities, their underlying mechanisms, and potential mitigation and monitoring strategies. Discussions addressed the clinical spectrum and biological drivers of these events, the respective roles of innate and adaptive immunity, the contribution of specific vector characteristics as well as of the specific disease and recipient. The application of risk stratification and immunosuppressive regimens for prevention, monitoring, and management were considered. Emerging toxicities, including capillary leak syndrome, endothelial and dorsal root ganglia injuries, were reviewed alongside corresponding preclinical data from non-human primates. Participants agreed on the need to harmonize standard operating procedures, clinical guidelines, and data-sharing practices, and endorsed collaborative initiatives to proactively address critical gaps and unresolved key questions through a patient-centered framework.

Adaptive immune response

The fungal RIP hypermutator mechanism has deep eukaryotic roots.

The repeat-induced point mutation (RIP) targets repeated sequences, such as transposable elements, in filamentous fungi. Host-transposable element coevolutionary dynamics have shaped taxonomically restricted eukaryotic defense systems, likely built on conserved ancestral mechanisms. Key questions surrounding homology recognition remain unresolved, and RIP offers a unique opportunity to answer them.

DNA Transposable Elements

Reconstructing the early spatial spread of pandemic respiratory viruses in the United States.

Understanding the geographic spread of emerging respiratory viruses is critical for pandemic preparedness, yet the early spatiotemporal dynamics of the 2009 H1N1 pandemic influenza and severe acute respiratory syndrome coronavirus 2 in the United States remain unclear. While mobility and genomic data have revealed important aspects of pandemic spatial spread, several key questions remain: Did the two pandemics follow similar spatial transmission routes? How rapidly did they spread across the United States? What role did stochastic processes play in early spatial transmission? To address these questions, we integrated high-resolution disease data with a robust, data-efficient inference framework combining air travel, commuting flows, and pathogen superspreading potentials to reconstruct their spatial spread across US metropolitan areas. The two pandemics exhibited distinct transmission pathways across locations; however, both pandemics established local circulation in most metropolitan areas within weeks, driven by several shared transmission hubs. Early spatial spread was more strongly associated with air travel than with commuting, though stochastic dynamics introduced substantial uncertainty in transmission routes, creating challenges for timely detection and control. Simulations indicate that broad wastewater surveillance coverage beyond top transmission hubs coupled with effective infection control may slow initial spatial expansion. Our findings highlight the rapid, stochastic spread of pandemic respiratory pathogens and the difficulties of early outbreak containment.

Humans

AQuA Tools: clear and reliable BEDPE operations for 3D genomics.

MOTIVATION: The genome interacts with itself within the volume of the cell nucleus to process information. These interactions mediate signal integration, gene regulation, and cell identity. The identification of new therapeutic targets from non-coding disease-associated variants relies critically on correctly assigning variants to genes through 3D interactions. Experimental techniques in 3D genomics, such as HiC and HiChIP, allow the mapping of interactions through sequencing. Bioinformatics for 3D genomics contends primarily with contact matrices that contain interaction frequencies for all possible element pairs, and BEDPE files that store element pairs that interact. Whereas the tools available for processing linear genomic data are mature, operating on contact matrices and BEDPE files remains cumbersome, opaque, and error-prone, as researchers have had to shoehorn tools originally designed for linear data. A genome arithmetic designed from the ground up for 3D genomics does not yet exist. RESULTS: We present AQuA Tools, a suite of shell- and R-based command-line tools that provide a set of core operations on contact matrices and BEDPE files motivated by key questions in population genetics, cancer research, and precision medicine. We have designed our core operations to be clear, reliable, intuitive and versatile. Core operations can be chained together along with standard UNIX commands. Our goal is to make AQuA Tools easy for the novice to learn and the go-to choice for power users. We hope our tools will motivate more researchers to use 3D genomic data in their projects. AVAILABILITY AND IMPLEMENTATION: We provide and maintain AQuA Tools at https://github.com/axiotl/aqua-tools.

Genomics

Biosynthesis of porphyrins and corrins.

Haem, chlorophyll and vitamin B12 are all derived ultimately from four molecules of the pyrrole porphobilinogen (PBG) and the initial enzyme catalysed condensation of PBG leads to the unsymmetrical type III isomer of uroporphyrinogen. On the basis of straightforward chemical considerations the type I isomer should be formed and so the porphyrinogen-forming enzymes of all living systems must catalyse a highly specific rearrangement process. The nature and chemical mechanism of this rearrangement poses one of the most fascinating problems in the porphyrin field and so it is not surprising that over 20 hypothetical schemes have been proposed to account for it. Analysis of the problem suggested that the incorporation of doubly 13C-labelled precursors into the rearranged macrocyclic rings would give valuable new information on the nature of the rearrangement process. In this approach the meso=bridge atoms are of crucial importance, and several unambiguous syntheses of 13C-labelled pyrroles and porphyrins were developed to allow rigorous n.m.r. assignments to be made, and also to provide substrates for enzymic experiments. Studies carried out with enzymes from both avian blood and from Euglena gracilis have revealed the precise nature of the assembly of four PBG molecules into the type-III macrocycle: it is the same in both systems despite their vastly different evolutionary development. Complementary studies are in progress in order to determine the intermediates involved in the conversion of PBG into uroporphyrinogen III. The synthesis of amino methyl pyrromethanes and their interaction in the presence of PBG with the appropriate enzyme systems are described. It is important for the work to be able to separate not only isomeric pyrromethanes but also the four isomeric coproporphyrins. Powerful methods are described which make use of high pressure liquid chromatography for both types of separation process. Once uroporhyrinogen III has been built enzymically, there is a stepwise enzymic decarboxylation of the four acetic acid residues. A heptacarboxylic porphyrin shown to be a type-III porphyrin is isolated from the action of avian blood enzymes on porphobilinogen. Spectroscopic studies with 13C-labelling limit the possible structures to two and total synthesis of these substances shows that the natural product carries its methyl group on ring D. An isomeric heptacarboxylic porphyrin having its methyl group on ring C is of particular interest in relation to the biosynthesis of vitamin B12. This substance is synthesized together with uroporphyrin III, 14C-labelled specifically in ring C. This latter product is used to settle one of the key questions concerning nature's route to vitamin B12 - that is, does the corrin macrocycle arise from uroporphyrinogen III? Incorporation studies and specific degradations prove specific incorporation of uroporphyrinogen III into cobyrinic acid, which is the known precursor of vitamin B12.

Models, Biological

New Genetic Loci Implicated in Cardiac Morphology and Function Using Three-Dimensional Population Phenotyping.

BACKGROUND: Cardiac remodeling occurs in the mature heart and is a cascade of adaptations in response to stress, which are primed in early life. A key question remains as to the processes that regulate the geometry and motion of the heart and how it adapts to stress. METHODS: We performed spatially resolved phenotyping using machine learning-based analysis of cardiac magnetic resonance imaging in 47 549 UK Biobank participants. We analyzed 16 left ventricular spatial phenotypes, including regional myocardial wall thickness and systolic strain in both circumferential and radial directions. In up to 40 058 participants, genetic associations across the allele frequency spectrum were assessed using genome-wide association studies with imputed genotype participants, and exome-wide association studies and gene-based burden tests using whole-exome sequencing data. We integrated transcriptomic data from the GTEx project and used pathway enrichment analyses to further interpret the biological relevance of identified loci. To investigate causal relationships, we conducted Mendelian randomization analyses to evaluate the effects of blood pressure on regional cardiac traits and the effects of these traits on cardiomyopathy risk. RESULTS: We found 42 loci associated with cardiac structure and contractility, many of which reveal patterns of spatial organization in the heart. Whole-exome sequencing revealed 3 additional variants not captured by the genome-wide association study, including a missense variant in CSRP3 (minor allele frequency 0.5%). The majority of newly discovered loci are found in cardiomyopathy-associated genes, suggesting that they regulate spatially distinct patterns of remodeling in the left ventricle in an adult population. Our causal analysis also found regional modulation of blood pressure on cardiac wall thickness and strain. CONCLUSIONS: These findings provide a comprehensive description of the pathways that orchestrate heart development and cardiac remodeling. These data highlight the role that cardiomyopathy-associated genes have on the regulation of spatial adaptations in those without known disease.

Humans

Utilization and cost of mental illness coverage in the Federal Employees Health Benefits Program, 1973.

The authors examine the utilization of mental illness benefits under the Blue Cross/Blue Shield and Aetna plans for federal employees; the latter plan sharply cut back its mental illness benefits in 1975. In 1973 mental illness benefits represented 7.4% of all payments under the Blues plan and 12% under the Aetna plan. The benefit for mental illness treatment under the Blues averaged $12.52 per person covered and was 7.3% of the total benefits for all conditions. Younger enrollees and their spouses tended to receive mental illness benefits primarily for outpatient treatment and children and older adults for hospitalization. These data raise key questions for claims review and peer review activities.

Adult

Interpreting cancer genetics through a two-step "evolutionary cascade hypothesis": bridging neutral and selective perspectives.

BACKGROUND: DNA mutations are the fundamental engines of cancer, driving its initiation and progression. The forces that fuel malignancy are also the architects of evolution, shaping life through genetic variations. Mutations, in fact, can emerge naturally from endogenous processes, such as oxidative DNA damage or errors in replication, as well as induced by external factors, including cosmic radiation and chemical carcinogens. MAIN BODY: A key question in cancer research is whether tumor evolution is primarily governed by selective bottlenecks, neutral evolution, or dynamic genetic plasticity. In this work, we examine cancer as a disease driven by evolutionary processes rooted in fundamental biological requirements, including sustained proliferation and nutrient utilization. We hypothesize that the accumulation of mutations activates an evolutionary switch, enabling tumor cells to acquire an enhanced capacity for survival, adaptation, and growth at rates far exceeding typical evolutionary timescales. We propose the "evolutionary cascade hypothesis," a unifying framework that integrates these models into a coherent sequence. At its core lies the failure of DNA repair mechanisms, representing a critical transition in cancer progression. This shift marks the transition from an initial non-Darwinian, neutral phase to a Darwinian, more deterministic phase. CONCLUSIONS: As predictive models of tumor evolution advance through genomic big data and artificial intelligence-driven analysis, the future of cancer treatment may extend beyond targeting individual mutations to disrupting the underlying evolutionary mechanisms that sustain malignancy. This paradigm shift could redefine therapeutic strategies and ultimately improve patient outcomes.

Humans

Forty new genomes shed light on sexual reproduction and the origin of tetraploidy in Microsporidia.

Microsporidia are single-celled, obligately intracellular parasites with growing public health, agricultural, and economic importance. Despite this, Microsporidia remain relatively enigmatic, with many aspects of their biology and evolution unexplored. Key questions include whether Microsporidia undergo sexual reproduction, and the nature of the relationship between tetraploid and diploid lineages. While few high-quality microsporidian genomes currently exist to help answer such questions, large-scale biodiversity genomics initiatives, such as the Darwin Tree of Life project, can generate high-quality genome assemblies for microsporidian parasites when sequencing infected host species. Here, we present 40 new microsporidian genome assemblies from infected arthropod hosts that were sequenced to create reference genomes. Out of the 40, 32 are complete genomes, eight of which are chromosome-level, and eight are partial microsporidian genomes. We characterized 14 of these as polyploid and five as diploid. We found that tetraploid genome haplotypes are consistent with autopolyploidy, in that they coalesce more recently than species, and that they likely recombine. Within some genomes, we found large-scale rearrangements between the homeologous genomes. We also observed a high rate of rearrangement between genomes from different microsporidian groups, and a striking tolerance for segmental duplications. Analysis of chromatin conformation capture (Hi-C) data indicated that tetraploid genomes are likely organized into two diploid units, similar to dikaryotic cells in fungi, with evidence of recombination within and between units. Together, our results provide evidence for the existence of a sexual cycle in Microsporidia, and suggest a model for the microsporidian lifecycle that mirrors fungal reproduction.

Genome, Fungal

Questions and replies: role of the collecting tubule in fluid, sodium, and potassium balance.

In terms of day-to-day regulation of fluid and electrolyte balance, the collecting tubule system appears to occupy a paramount position among segments of the renal tubule. Controversy has arisen concerning the quantitative contribution by the collecting tubule system to the regulation of individual solute excretion, which in part may be due to differences among the investigative techniques employed. In this Editorial Review, R. L. Jamison summarizes current views on the function of the collecting tubule system, particularly with regard to regulation of sodium and potassium excretion, and then poses seven questions pertaining to this topic. H. Sonnenberg, who has revived the microcatheterization technique, and J. H. Stein, whose group has employed the micropuncture method, respond to these questions. The key issues addressed are: 1) the principal factors that influence transtubular movement of sodium and potassium across the collecting tubule; 2) the limitations and potential artifacts of the microcatheterization and micropuncture techniques when used to examine the function of the collecting tubule; 3) apparent discrepancies among results obtained by micropuncture in vivo, microcatheterization in vivo, and microperfusion in vitro of the collecting tubule; and 4) major unresolved questions concerning the function of the collecting tubule.

Animals