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1.
J Fish Biol ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39109654

RESUMEN

Winter flounder Pseudopleuronectes americanus (Walbaum 1792) are a coastal flatfish species of economic and cultural importance that have dwindled to <15, % of their historic abundance in the southern New England/Mid-Atlantic region of the United States, with evidence indicating near-extirpation of certain local populations. This species exhibits intricate behaviors in spawning and migration that contribute to population complexity and resilience. These behaviors encompass full or partial philopatry to natal estuaries, the generation of multiple pulses of larval delivery, and partial migration. The patterns of genetic diversity within and among estuaries and cohorts presented here carry important implications in understanding the susceptibility to demographic shocks, even if the full extent of genetic diversity within and among winter flounder stocks on the US East Coast remains unresolved. Our findings reveal connectivity between estuaries in Long Island, New York, suggesting the potential for genetic rescue of depleted subpopulations. Family reconstruction and relatedness analysis indicate that split cohorts and migration contingents are not the result of genetically distinct lineages. We found no evidence for genetic structure separating these groups, and in some instances, we were able to detect closely related individuals that belonged to different migratory contingents or cohorts. Characterizing the spatial and behavioral organization of this species at the population level is crucial for comprehending its potential for recovery, not only in terms of biomass but also in reinstating the complex population structure that supports resilience. The search for generality in winter flounder spawning and migration behavior remains elusive, but perhaps the lack of generalities within this species is what has allowed it to persist in the face of decades of environmental and anthropogenic stressors.

2.
Front Cell Dev Biol ; 12: 1399005, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39114569

RESUMEN

Introduction: Many survivors of preterm birth (<37 weeks gestation) have lifelong respiratory deficits, the drivers of which remain unknown. Influencers of pathophysiological outcomes are often detectable at the gene level and pinpointing these differences can help guide targeted research and interventions. This study provides the first transcriptomic analysis of primary nasal airway epithelial cells in survivors of preterm birth at approximately 1 year of age. Methods: Nasal airway epithelial brushings were collected, and primary cell cultures established from term (>37 weeks gestation) and very preterm participants (≤32 weeks gestation). Ex vivo RNA was collected from brushings with sufficient cell numbers and in vitro RNA was extracted from cultured cells, with bulk RNA sequencing performed on both the sample types. Differential gene expression was assessed using the limma-trend pipeline and pathway enrichment identified using Reactome and GO analysis. To corroborate gene expression data, cytokine concentrations were measured in cell culture supernatant. Results: Transcriptomic analysis to compare term and preterm cells revealed 2,321 genes differentially expressed in ex vivo samples and 865 genes differentially expressed in cultured basal cell samples. Over one third of differentially expressed genes were related to host immunity, with interferon signalling pathways dominating the pathway enrichment analysis and IRF1 identified as a hub gene. Corroboration of disrupted interferon release showed that concentrations of IFN-α2 were below measurable limits in term samples but elevated in preterm samples [19.4 (76.7) pg/ml/µg protein, p = 0.03]. IFN-γ production was significantly higher in preterm samples [3.3 (1.5) vs. 9.4 (17.7) pg/ml/µg protein; p = 0.01] as was IFN-ß [7.8 (2.5) vs. 13.6 (19.5) pg/ml/µg protein, p = 0.01]. Conclusion: Host immunity may be compromised in the preterm nasal airway epithelium in early life. Altered immune responses may lead to cycles of repeated infections, causing persistent inflammation and tissue damage which can have significant impacts on long-term respiratory function.

3.
Phys Med Biol ; 69(18)2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39159658

RESUMEN

Radiotherapy has played an essential role in cancer treatment for over a century, and remains one of the best-studied methods of cancer treatment. Because of its close links with the physical sciences, it has been the subject of extensive quantitative mathematical modelling, but a complete understanding of the mechanisms of radiotherapy has remained elusive. In part this is because of the complexity and range of scales involved in radiotherapy-from physical radiation interactions occurring over nanometres to evolution of patient responses over months and years. This review presents the current status and ongoing research in modelling radiotherapy responses across these scales, including basic physical mechanisms of DNA damage, the immediate biological responses this triggers, and genetic- and patient-level determinants of response. Finally, some of the major challenges in this field and potential avenues for future improvements are also discussed.


Asunto(s)
Modelos Biológicos , Radiobiología , Humanos , Daño del ADN , Neoplasias/radioterapia
4.
Int J Mol Sci ; 25(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39201793

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a fatal disease that causes degeneration of motor neurons (MNs) and paralysis. ALS can be caused by mutations in the gene that encodes copper/zinc superoxide dismutase (SOD1). SOD1 is known mostly as a cytosolic antioxidant protein, but SOD1 is also in the nucleus of non-transgenic (tg) and human SOD1 (hSOD1) tg mouse MNs. SOD1's nuclear presence in different cell types and subnuclear compartmentations are unknown, as are the nuclear functions of SOD1. We examined hSOD1 nuclear localization and DNA damage in tg mice expressing mutated and wildtype variants of hSOD1 (hSOD1-G93A and hSOD1-wildtype). We also studied ALS patient-derived induced pluripotent stem (iPS) cells to determine the nuclear presence of SOD1 in undifferentiated and differentiated MNs. In hSOD1-G93A and hSOD1-wildtype tg mice, choline acetyltransferase (ChAT)-positive MNs had nuclear hSOD1, but while hSOD1-wildtype mouse MNs also had nuclear ChAT, hSOD1-G93A mouse MNs showed symptom-related loss of nuclear ChAT. The interneurons had preserved parvalbumin nuclear positivity in hSOD1-G93A mice. hSOD1-G93A was seen less commonly in spinal cord astrocytes and, notably, oligodendrocytes, but as the disease emerged, the oligodendrocytes had increased mutant hSOD1 nuclear presence. Brain and spinal cord subcellular fractionation identified mutant hSOD1 in soluble nuclear extracts of the brain and spinal cord, but mutant hSOD1 was concentrated in the chromatin nuclear extract only in the spinal cord. Nuclear extracts from mutant hSOD1 tg mouse spinal cords had altered protein nitration, footprinting peroxynitrite presence, and the intact nuclear extracts had strongly increased superoxide production as well as the active NADPH oxidase marker, p47phox. The comet assay showed that MNs from hSOD1-G93A mice progressively (6-14 weeks of age) accumulated DNA single-strand breaks. Ablation of the NCF1 gene, encoding p47phox, and pharmacological inhibition of NADPH oxidase with systemic treatment of apocynin (10 mg/kg, ip) extended the mean lifespan of hSOD1-G93A mice by about 25% and mitigated genomic DNA damage progression. In human postmortem CNS, SOD1 was found in the nucleus of neurons and glia; nuclear SOD1 was increased in degenerating neurons in ALS cases and formed inclusions. Human iPS cells had nuclear SOD1 during directed differentiation to MNs, but mutant SOD1-expressing cells failed to establish wildtype MN nuclear SOD1 levels. We conclude that SOD1 has a prominent nuclear presence in the central nervous system, perhaps adopting aberrant contexts to participate in ALS pathobiology.


Asunto(s)
Esclerosis Amiotrófica Lateral , Núcleo Celular , Daño del ADN , Células Madre Pluripotentes Inducidas , Neuronas Motoras , Estrés Oxidativo , Superóxido Dismutasa-1 , Animales , Humanos , Ratones , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/patología , Núcleo Celular/metabolismo , Modelos Animales de Enfermedad , Células Madre Pluripotentes Inducidas/metabolismo , Ratones Transgénicos , Neuronas Motoras/metabolismo , Neuronas Motoras/patología , NADPH Oxidasas/metabolismo , NADPH Oxidasas/genética , Fenotipo , Médula Espinal/metabolismo , Médula Espinal/patología , Superóxido Dismutasa-1/genética , Superóxido Dismutasa-1/metabolismo
5.
J Neurosurg Pediatr ; : 1-9, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39178478

RESUMEN

OBJECTIVE: Hydrocephalus is a challenging neurosurgical condition due to nonspecific symptoms and complex brain-fluid pressure dynamics. Typically, the assessment of hydrocephalus in children requires radiographic or invasive pressure monitoring. There is usually a qualitative focus on the ventricular spaces even though stress and shear forces extend across the brain. Here, the authors present an MRI-based vector approach for voxelwise brain and ventricular deformation visualization and analysis. METHODS: Twenty pediatric patients (mean age 7.7 years, range 6 months-18 years; 14 males) with acute, newly diagnosed hydrocephalus requiring surgical intervention for symptomatic relief were randomly identified after retrospective chart review. Selection criteria included acquisition of both pre- and posttherapy paired 3D T1-weighted volumetric MRI (3D T1-MRI) performed on 3T MRI systems. Both pre- and posttherapy 3D T1-MRI pairs were aligned using image registration, and subsequently, voxelwise nonlinear transformations were performed to derive two exemplary visualizations of compliance: 1) a whole-brain vector map projecting the resulting deformation field on baseline axial imaging; and 2) a 3D heat map projecting the volumetric changes along ventricular boundaries and the brain periphery. RESULTS: The patients underwent the following interventions for treatment of hydrocephalus: endoscopic third ventriculostomy (n = 6); external ventricular drain placement and/or tumor resection (n = 10); or ventriculoperitoneal shunt placement (n = 4). The mean time between pre- and postoperative imaging was 36.5 days. Following intervention, the ventricular volumes decreased significantly (mean pre- and posttherapy volumes of 151.9 cm3 and 82.0 cm3, respectively; p < 0.001, paired t-test). The largest degree of deformation vector changes occurred along the lateral ventricular spaces, relative to the genu and splenium. There was a significant correlation between change in deformation vector magnitudes within the cortical layer and age (p = 0.011, Pearson), as well as between the ventricle size and age (p = 0.014, Pearson), suggesting higher compliance among infants and younger children. CONCLUSIONS: This study highlights an approach for deformation analysis and vector mapping that may serve as a topographic visualizer for therapeutic interventions in patients with hydrocephalus. A future study that correlates the degree of cerebroventricular deformation or compliance with intracranial pressures could clarify the potential role of this technique in noninvasive pressure monitoring or in cases of noncompliant ventricles.

6.
Nucleic Acids Res ; 52(16): 9777-9787, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39106172

RESUMEN

Type II topoisomerases (topos) are a ubiquitous and essential class of enzymes that form transient enzyme-bound double-stranded breaks on DNA called cleavage complexes. The location and frequency of these cleavage complexes on DNA is important for cellular function, genomic stability and a number of clinically important anticancer and antibacterial drugs, e.g. quinolones. We developed a simple high-accuracy end-sequencing (SHAN-seq) method to sensitively map type II topo cleavage complexes on DNA in vitro. Using SHAN-seq, we detected Escherichia coli gyrase and topoisomerase IV cleavage complexes at hundreds of sites on supercoiled pBR322 DNA, approximately one site every ten bp, with frequencies that varied by two-to-three orders of magnitude. These sites included previously identified sites and 20-50-fold more new sites. We show that the location and frequency of cleavage complexes at these sites are enzyme-specific and vary substantially in the presence of the quinolone, ciprofloxacin, but not with DNA supercoil chirality, i.e. negative versus positive supercoiling. SHAN-seq's exquisite sensitivity provides an unprecedented single-nucleotide resolution view of the distribution of gyrase and topoisomerase IV cleavage complexes on DNA. Moreover, the discovery that these enzymes can cleave DNA at orders of magnitude more sites than the relatively few previously known sites resolves the apparent paradox of how these enzymes resolve topological problems throughout the genome.


Asunto(s)
División del ADN , Girasa de ADN , Topoisomerasa de ADN IV , ADN-Topoisomerasas de Tipo II , Escherichia coli , Escherichia coli/genética , Escherichia coli/enzimología , Girasa de ADN/metabolismo , Girasa de ADN/genética , Girasa de ADN/química , Topoisomerasa de ADN IV/metabolismo , Topoisomerasa de ADN IV/genética , Topoisomerasa de ADN IV/química , ADN-Topoisomerasas de Tipo II/metabolismo , ADN-Topoisomerasas de Tipo II/genética , Análisis de Secuencia de ADN/métodos , ADN Superhelicoidal/metabolismo , ADN Superhelicoidal/química , Ciprofloxacina/farmacología , Secuenciación de Nucleótidos de Alto Rendimiento , ADN/metabolismo , ADN/química
7.
Clin Neurol Neurosurg ; 244: 108442, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39038420

RESUMEN

BACKGROUND: Delays in intravenous thrombolysis (IVT) treatment for acute ischemic stroke decrease the benefit of treatment. Difficulties determining a patient's clinical eligibility for IVT is a frequent cause of treatment delays. OBJECTIVE: We aimed to assess the effectiveness of the "PROVIDENCE" datasheet, a pre- hospital assessment of contraindications for IVT use applied by emergency medical services personnel. METHODS: We performed a single-center cohort study comparing IVT decision and treatment times between patients with PROVIDENCE datasheets and those without. Patients were eligible if they were over 18 years old and presented to our comprehensive stroke center from the field with stroke-like symptoms with onset within 4.5 hours. RESULTS: We identified 465 records and included 166 records in our final analysis (54 in the study group and 112 in the control group). A subgroup of 85 patients received IVT (30 in the study group patients and 55 in the control group). The PROVIDENCE datasheet was associated with a faster median time by five minutes from the patient's initial presentation at the emergency department to the final decision regarding IVT eligibility (p = 0.032) and a faster time between the first encounter with a neurology provider and the decision regarding IVT administration by six minutes (p = 0.002) for the entire sample. In the subgroup that received IVT, the PROVIDENCE datasheet decreased the median decision time by seven minutes (p = 0.044) There was no significant difference in door-to-needle times between groups. CONCLUSION: Using the PROVIDENCE datasheet, first responders can quickly identify potential contraindications for IVT treatment in patients with stroke-like symptoms. This tool expedited decision-making and led to faster IVT administration process at a comprehensive stroke center.


Asunto(s)
Servicios Médicos de Urgencia , Accidente Cerebrovascular Isquémico , Terapia Trombolítica , Tiempo de Tratamiento , Humanos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/terapia , Masculino , Femenino , Anciano , Persona de Mediana Edad , Servicios Médicos de Urgencia/métodos , Terapia Trombolítica/métodos , Encuestas y Cuestionarios , Estudios de Cohortes , Fibrinolíticos/uso terapéutico , Fibrinolíticos/administración & dosificación , Anciano de 80 o más Años
8.
J Am Chem Soc ; 146(29): 20009-20018, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38980280

RESUMEN

High-throughput computational materials discovery has promised significant acceleration of the design and discovery of new materials for many years. Despite a surge in interest and activity, the constraints imposed by large-scale computational resources present a significant bottleneck. Furthermore, examples of very large-scale computational discovery carried out through experimental validation remain scarce, especially for materials with product applicability. Here, we demonstrate how this vision became reality by combining state-of-the-art machine learning (ML) models and traditional physics-based models on cloud high-performance computing (HPC) resources to quickly navigate through more than 32 million candidates and predict around half a million potentially stable materials. By focusing on solid-state electrolytes for battery applications, our discovery pipeline further identified 18 promising candidates with new compositions and rediscovered a decade's worth of collective knowledge in the field as a byproduct. We then synthesized and experimentally characterized the structures and conductivities of our top candidates, the NaxLi3-xYCl6 (0≤ x≤ 3) series, demonstrating the potential of these compounds to serve as solid electrolytes. Additional candidate materials that are currently under experimental investigation could offer more examples of the computational discovery of new phases of Li- and Na-conducting solid electrolytes. The showcased screening of millions of materials candidates highlights the transformative potential of advanced ML and HPC methodologies, propelling materials discovery into a new era of efficiency and innovation.

9.
Ecol Evol ; 14(6): e11514, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38859886

RESUMEN

Patterns of genetic variation reflect interactions among microevolutionary forces that vary in strength with changing demography. Here, patterns of variation within and among samples of the mouthbrooding gafftopsail catfish (Bagre marinus, Family Ariidae) captured in the U.S. Atlantic and throughout the Gulf of Mexico were analyzed using genomics to generate neutral and non-neutral SNP data sets. Because genomic resources are lacking for ariids, linkage disequilibrium network analysis was used to examine patterns of putatively adaptive variation. Finally, historical demographic parameters were estimated from site frequency spectra. The results show four differentiated groups, corresponding to the (1) U.S. Atlantic, and the (2) northeastern, (3) northwestern, and (4) southern Gulf of Mexico. The non-neutral data presented two contrasting signals of structure, one due to increases in diversity moving west to east and north to south, and another to increased heterozygosity in the Atlantic. Demographic analysis suggested that recently reduced long-term effective population size in the Atlantic is likely an important driver of patterns of genetic variation and is consistent with a known reduction in population size potentially due to an epizootic. Overall, patterns of genetic variation resemble that of other fishes that use the same estuarine habitats as nurseries, regardless of the presence/absence of a larval phase, supporting the idea that adult/juvenile behavior and habitat are important predictors of contemporary patterns of genetic structure.

10.
bioRxiv ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38915629

RESUMEN

Stalled replication forks can be processed by several distinct mechanisms collectively called post-replication repair which includes homologous recombination, fork regression, and translesion DNA synthesis. However, the regulation of the usage between these pathways is not fully understood. The Rad51 protein plays a pivotal role in maintaining genomic stability through its roles in HR and in protecting stalled replication forks from degradation. We report the isolation of separation-of-function mutations in Saccharomyces cerevisiae Rad51 that retain their recombination function but display a defect in fork protection leading to a shift in post-replication repair pathway usage from HR to alternate pathways including mutagenic translesion synthesis. Rad51-E135D and Rad51-K305N show normal in vivo and in vitro recombination despite changes in their DNA binding profiles, in particular to dsDNA, with a resulting effect on their ATPase activities. The mutants lead to a defect in Rad51 recruitment to stalled forks in vivo as well as a defect in the protection of dsDNA from degradation by Dna2-Sgs1 and Exo1 in vitro . A high-resolution cryo-electron microscopy structure of the Rad51-ssDNA filament at 2.4 Å resolution provides a structural basis for a mechanistic understanding of the mutant phenotypes. Together, the evidence suggests a model in which Rad51 binding to duplex DNA is critical to control pathway usage at stalled replication forks.

11.
Invest Ophthalmol Vis Sci ; 65(6): 33, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38904639

RESUMEN

Purpose: Recent studies have shown that the retinal pigment epithelium (RPE) relies on fatty acid oxidation (FAO) for energy, however, its role in overall retinal health is unknown. The only FAO disorder that presents with chorioretinopathy is long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD). Studying the molecular mechanisms can lead to new treatments for patients and elucidate the role of FAO in the RPE. This paper characterizes the chorioretinopathy progression in a recently reported LCHADD mouse model. Methods: Visual assessments, such as optokinetic tracking and fundus imaging, were performed in wildtype (WT) and LCHADD mice at 3, 6, 10, and 12 months of age. Retinal morphology was analyzed in 12-month retinal cross-sections using hematoxylin and eosin (H&E), RPE65, CD68, and TUNEL staining, whereas RPE structure was assessed using transmission electron microscopy (TEM). Acylcarnitine profiles were measured in isolated RPE/sclera samples to determine if FAO was blocked. Bulk RNA-sequencing of 12 month old male WT mice and LCHADD RPE/sclera samples assessed gene expression changes. Results: LCHADD RPE/sclera samples had a 5- to 7-fold increase in long-chain hydroxyacylcarnitines compared to WT, suggesting an impaired LCHAD step in long-chain FAO. LCHADD mice have progressively decreased visual performance and increased RPE degeneration starting at 6 months. LCHADD RPE have an altered structure and a two-fold increase in macrophages in the subretinal space. Finally, LCHADD RPE/sclera have differentially expressed genes compared to WT, including downregulation of genes important for RPE function and angiogenesis. Conclusions: Overall, this LCHADD mouse model recapitulates early-stage chorioretinopathy seen in patients with LCHADD and is a useful model for studying LCHADD chorioretinopathy.


Asunto(s)
Modelos Animales de Enfermedad , Epitelio Pigmentado de la Retina , Animales , Ratones , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Ratones Endogámicos C57BL , 3-Hidroxiacil-CoA Deshidrogenasa de Cadena Larga/metabolismo , Enfermedades de la Coroides/genética , Enfermedades de la Coroides/metabolismo , Masculino , Enfermedades de la Retina/genética , Enfermedades de la Retina/metabolismo , Enfermedades de la Retina/fisiopatología , Microscopía Electrónica de Transmisión
12.
Nat Biomed Eng ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710838

RESUMEN

Following immunization, lymph nodes dynamically expand and contract. The mechanical and cellular changes enabling the early-stage expansion of lymph nodes have been characterized, yet the durability of such responses and their implications for adaptive immunity and vaccine efficacy are unknown. Here, by leveraging high-frequency ultrasound imaging of the lymph nodes of mice, we report more potent and persistent lymph-node expansion for animals immunized with a mesoporous silica vaccine incorporating a model antigen than for animals given bolus immunization or standard vaccine formulations such as alum, and that durable and robust lymph-node expansion was associated with vaccine efficacy and adaptive immunity for 100 days post-vaccination in a mouse model of melanoma. Immunization altered the mechanical and extracellular-matrix properties of the lymph nodes, drove antigen-dependent proliferation of immune and stromal cells, and altered the transcriptional features of dendritic cells and inflammatory monocytes. Strategies that robustly maintain lymph-node expansion may result in enhanced vaccination outcomes.

13.
Clin Transl Gastroenterol ; 15(6): e1, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38742743

RESUMEN

INTRODUCTION: We designed a race-conscious study to assess the presence of Helicobacter pylori v irulence factor cagA in a retrospective cohort of patients with active H. pylori infection. METHODS: We compared cagA status by race in gastric tissue samples from 473 patients diagnosed with active H. pylori infection from 2015 to 2019. RESULTS: H. pylori + Black patients were 2 times more likely to be cagA + than H. pylori + White patients (82% vs 36%, P < .0001). DISCUSSION: Presence of cagA is common among endoscopy patients with active H. pylori infection; appropriate testing and treatment of H. pylori can both reduce gastric cancer risk and address health disparities.


Asunto(s)
Antígenos Bacterianos , Proteínas Bacterianas , Infecciones por Helicobacter , Helicobacter pylori , Factores de Virulencia , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Antígenos Bacterianos/análisis , Negro o Afroamericano/estadística & datos numéricos , Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/aislamiento & purificación , Prevalencia , Estudios Retrospectivos , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/epidemiología , Factores de Virulencia/análisis , Población Blanca/estadística & datos numéricos
14.
NPJ Precis Oncol ; 8(1): 124, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822082

RESUMEN

Acquired resistance remains a major challenge for therapies targeting oncogene activated pathways. KRAS is the most frequently mutated oncogene in human cancers, yet strategies targeting its downstream signaling kinases have failed to produce durable treatment responses. Here, we developed multiple models of acquired resistance to dual-mechanism ERK/MAPK inhibitors across KRAS-mutant pancreatic, colorectal, and lung cancers, and then probed the long-term events enabling survival against this class of drugs. These studies revealed that resistance emerges secondary to large-scale transcriptional adaptations that are diverse and cell line-specific. Transcriptional reprogramming extends beyond the well-established early response, and instead represents a dynamic, evolved process that is refined to attain a stably resistant phenotype. Mechanistic and translational studies reveal that resistance to dual-mechanism ERK/MAPK inhibition is broadly susceptible to manipulation of the epigenetic machinery, and that Mediator kinase, in particular, can be co-targeted at a bottleneck point to prevent diverse, cell line-specific resistance programs.

15.
Sci Total Environ ; 942: 173467, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-38802007

RESUMEN

Stormwater ponds are increasingly becoming a dominant pond type in cities experiencing urban sprawl. These human-made ponds are designed primarily to control flooding issues associated with increased impervious surface in cities and serve to retain sediment and contaminants before flowing to urban downstream waterways. Along with these important functions, constructed ponds including stormwater ponds may be critical in urban freshwater conservation because they often represent some of the few remaining lentic environments (still water; e.g. ponds, wetlands, lakes) in many cities. We currently lack a clear understanding of the role that stormwater ponds play in serving as habitat for freshwater biodiversity. Here, we examined whether stormwater ponds support freshwater biodiversity in cities by reviewing the empirical literature on biotic community responses in urban stormwater ponds across a range of taxonomic groups. We conducted a meta-analysis on empirical papers that quantitatively examined differences in taxonomic richness between stormwater ponds and reference ponds (n = 11 papers, 22 effects). We also examined a broader set of 58 papers to qualitatively synthesize studies on stormwater pond communities and assess various indicators of habitat quality in stormwater ponds. In the studies examined, heterogeneity exists in the habitat quality of stormwater ponds and increased pollutant loads are often reported. However, the results highlight that stormwater ponds tend to contain alpha diversity comparable to reference ponds, and that overall, a range of ecologically important wildlife make use of and inhabit urban stormwater ponds. We find that stormwater ponds can often support communities with broad compositions of taxa, including those that are sensitive or vulnerable to environmental change. We compile recommendations provided within the studies in order to improve our understanding of the management of urban stormwater ponds for biodiversity conservation.


Asunto(s)
Biodiversidad , Ecosistema , Agua Dulce , Estanques , Conservación de los Recursos Naturales/métodos , Humedales , Animales , Ciudades
16.
bioRxiv ; 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38798569

RESUMEN

Type II topoisomerases (topos) are a ubiquitous and essential class of enzymes that form transient enzyme-bound double-stranded breaks on DNA called cleavage complexes. The location and frequency of these cleavage complexes on DNA is important for cellular function, genomic stability, and a number of clinically important anticancer and antibacterial drugs, e.g., quinolones. We developed a simple high-accuracy end-sequencing (SHAN-seq) method to sensitively map type II topo cleavage complexes on DNA in vitro. Using SHAN-seq, we detected Escherichia coli gyrase and topoisomerase IV cleavage complexes at hundreds of sites on supercoiled pBR322 DNA, approximately one site every ten bp, with frequencies that varied by two-to-three orders of magnitude. These sites included previously identified sites and 20-50 fold more new sites. We show that the location and frequency of cleavage complexes at these sites are enzyme-specific and vary substantially in the presence of the quinolone, ciprofloxacin, but not with DNA supercoil chirality, i.e., negative vs. positive supercoiling. SHAN-seq's exquisite sensitivity provides an unprecedented single-nucleotide resolution view of the distribution of gyrase and topoisomerase IV cleavage complexes on DNA. Moreover, the discovery that these enzymes can cleave DNA at orders of magnitude more sites than the relatively few previously known sites resolves the apparent paradox of how these enzymes resolve topological problems throughout the genome.

17.
Cell Commun Signal ; 22(1): 221, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38594674

RESUMEN

VEGFR2 (Vascular endothelial growth factor receptor 2) is a central regulator of placental angiogenesis. The study of the VEGFR2 proteome of chorionic villi at term revealed its partners MDMX (Double minute 4 protein) and PICALM (Phosphatidylinositol-binding clathrin assembly protein). Subsequently, the oxytocin receptor (OT-R) and vasopressin V1aR receptor were detected in MDMX and PICALM immunoprecipitations. Immunogold electron microscopy showed VEGFR2 on endothelial cell (EC) nuclei, mitochondria, and Hofbauer cells (HC), tissue-resident macrophages of the placenta. MDMX, PICALM, and V1aR were located on EC plasma membranes, nuclei, and HC nuclei. Unexpectedly, PICALM and OT-R were detected on EC projections into the fetal lumen and OT-R on 20-150 nm clusters therein, prompting the hypothesis that placental exosomes transport OT-R to the fetus and across the blood-brain barrier. Insights on gestational complications were gained by univariable and multivariable regression analyses associating preeclampsia with lower MDMX protein levels in membrane extracts of chorionic villi, and lower MDMX, PICALM, OT-R, and V1aR with spontaneous vaginal deliveries compared to cesarean deliveries before the onset of labor. We found select associations between higher MDMX, PICALM, OT-R protein levels and either gravidity, diabetes, BMI, maternal age, or neonatal weight, and correlations only between PICALM-OT-R (p < 2.7 × 10-8), PICALM-V1aR (p < 0.006), and OT-R-V1aR (p < 0.001). These results offer for exploration new partnerships in metabolic networks, tissue-resident immunity, and labor, notably for HC that predominantly express MDMX.


Asunto(s)
Diabetes Mellitus , Preeclampsia , Femenino , Humanos , Recién Nacido , Embarazo , Número de Embarazos , Oxitocina/metabolismo , Placenta/metabolismo , Preeclampsia/metabolismo , Proteómica , Receptores de Oxitocina/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
18.
Pediatrics ; 153(5)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38646685

RESUMEN

CONTEXT: Acute sinusitis is one of the leading causes of antibiotic prescriptions in children. No recent systematic reviews have examined the efficacy of antibiotics compared with placebo. OBJECTIVE: We sought to determine if antibiotics are superior to placebo in the treatment of acute sinusitis in children. DATA SOURCES: Medline and Embase were searched from their origin to July 2023. STUDY SELECTION: We considered randomized placebo-controlled studies focusing on the treatment of acute sinusitis. In all studies, symptoms were present for <4 weeks and subjects were <18 years of age. DATA EXTRACTION: Two authors independently extracted the data. We pooled data primarily using fixed-effects models. RESULTS: Analysis of 6 included studies showed that antibiotic treatment reduced the rate of treatment failure by 41% (with a risk ratio of 0.59; 95% confidence interval 0.49-0.72) compared with placebo. There was substantial heterogeneity between the studies (I2 = 69.7%), which decreased substantially when the 1 study with a high risk of bias was removed (I2 = 26.9%). Children treated with antibiotics were 1.6 times more likely to have diarrhea than those who were not treated with antibiotics (risk ratio = 1.62, 95% confidence interval 1.04-2.51). LIMITATIONS: A small number of studies were eligible for inclusion. Included studies differed in their methodology. CONCLUSIONS: In children with clinically diagnosed acute sinusitis, antibiotics significantly reduced the rate of treatment failure compared with placebo. However, given the favorable natural history of sinusitis, our results could also support close observation without immediate antibiotic treatment.


Asunto(s)
Antibacterianos , Sinusitis , Humanos , Antibacterianos/uso terapéutico , Sinusitis/tratamiento farmacológico , Niño , Enfermedad Aguda , Ensayos Clínicos Controlados Aleatorios como Asunto , Insuficiencia del Tratamiento , Adolescente
19.
Clin Genitourin Cancer ; 22(3): 102080, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38653037

RESUMEN

BACKGROUND: There is currently limited literature assessing the real-world treatment patterns and clinical outcomes of patients with metastatic castration-resistant prostate cancer (mCRPC) and homologous recombination repair (HRR) mutations. METHODS: Medical charts were abstracted for mCRPC patients with ≥ 1 of 12 HRR somatic gene alterations treated at US oncology centers participating in the American Association for Cancer Research Project Genomics Evidence Neoplasia Information Exchange. Treatment patterns and clinical outcomes were assessed from the initiation of first-line or later (1L+) mCRPC therapy received on or after July 1, 2014. RESULTS: Among 138 patients included in the study, the most common somatic HRR mutations were CDK12 (47.8%), BRCA2 (22.5%), and ATM (21.0%). Novel hormonal therapy and taxane chemotherapy were most commonly used in 1L; taxane use increased in later lines. Median overall survival (95% confidence interval [CI]) was 36.3 (30.7-47.8) months from initiation of 1L therapy and decreased for subsequent lines. Similarly, there was a trend of decreasing progression-free survival and prostate-specific antigen response from 1L to 4L+ therapy. CONCLUSIONS: Treatment patterns identified in this study were similar to those among patients with mCRPC regardless of tumor HRR mutation status in the literature.


Asunto(s)
Proteína BRCA2 , Mutación , Neoplasias de la Próstata Resistentes a la Castración , Reparación del ADN por Recombinación , Humanos , Masculino , Anciano , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/patología , Proteína BRCA2/genética , Persona de Mediana Edad , Proteínas de la Ataxia Telangiectasia Mutada/genética , Taxoides/uso terapéutico , Taxoides/administración & dosificación , Quinasas Ciclina-Dependientes/genética , Resultado del Tratamiento , Anciano de 80 o más Años , Antígeno Prostático Específico/sangre , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Hidrocarburos Aromáticos con Puentes/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estudios Retrospectivos , Metástasis de la Neoplasia
20.
Bioprocess Biosyst Eng ; 47(8): 1227-1240, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38653840

RESUMEN

While monospecific antibodies have long been the foundational offering of protein therapeutics, recent advancements in antibody engineering have allowed for the development of far more complex antibody structures. Novel molecular format (NMF) proteins, such as bispecific antibodies (BsAbs), are structures capable of multispecific binding, allowing for expanded therapeutic functionality. As demand for NMF proteins continues to rise, biomanufacturers face the challenge of increasing bioreactor process productivity while simultaneously maintaining consistent product quality. This challenge is exacerbated when producing structurally complex proteins with asymmetric modalities, as seen in NMFs. In this study, the impact of a high inoculation density (HID) fed-batch process on the productivity and product quality attributes of two CHO cell lines expressing unique NMFs, a monospecific antibody with an Fc-fusion protein and a bispecific antibody, compared to low inoculation density (LID) platform fed-batch processes was evaluated. It was observed that an intensified platform fed-batch process increased product concentrations by 33 and 109% for the two uniquely structured complex proteins in a shorter culture duration while maintaining similar product quality attributes to traditional fed-batch processes.


Asunto(s)
Reactores Biológicos , Cricetulus , Células CHO , Animales , Anticuerpos Biespecíficos/biosíntesis , Técnicas de Cultivo Celular por Lotes , Cricetinae , Proteínas Recombinantes/biosíntesis
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