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1.
Blood Adv ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38968150

RESUMO

Platelet CLEC-2 is a hemITAM-containing receptor which has a critical role in venous thrombosis, but minimal involvement in haemostasis. CLEC-2 can be blocked by Btk inhibitors. Treatment with ibrutinib is associated with increased bleeding due to off-target inhibition of Src family kinases (SFKs). Patients with X-linked agammaglobulinemia (XLA) who lack Btk however do not bleed, suggesting selective Btk inhibition is a viable antithrombotic strategy. We assessed the effects of selective Btk inhibitors PRN1008 (rilzabrutinib) and PRN473 on platelet signalling and function mediated by CLEC-2 and GPVI. We used healthy donor and XLA platelets to determine off-target inhibitor effects. Inferior vena cava (IVC) stenosis and Salmonella infection mouse models were used to assess antithrombotic effects of PRN473 in vivo. PRN1008 and PRN473 potently inhibited CLEC-2-mediated platelet activation to rhodocytin. No off-target inhibition of SFKs was seen. PRN1008 treatment of Btk-deficient platelets resulted in minor additional inhibition of aggregation and tyrosine phosphorylation, likely reflecting inhibition of Tec. No effect on GPCR-mediated platelet function was observed. PRN473 significantly reduced the number of thrombi in podoplanin positive vessels following Salmonella infection and the presence of IVC thrombosis following vein stenosis. The potent inhibition of human platelet CLEC-2, and reduced thrombosis in in vivo models, together with the lack of off-target SFK inhibition and absence of bleeding reported in rilzabrutinib treated immune thrombocytopenia patients, suggest Btk inhibition as a promising antithrombotic strategy.

2.
Small ; : e2401015, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38966889

RESUMO

Although tendon predominantly experiences longitudinal tensile forces, transverse forces due to impingement from bone are implicated in both physiological and pathophysiological processes. However, prior studies have not characterized the micromechanical strain environment in the context of tendon impingement. To address this knowledge gap, mouse hindlimb explants are imaged on a multiphoton microscope, and image stacks of the same population of tendon cells are obtained in the Achilles tendon before and after dorsiflexion-induced impingement by the heel bone. Based on the acquired images, multiaxial strains are measured at the extracellular matrix (ECM), pericellular matrix (PCM), and cell scales. Impingement generated substantial transverse compression at the matrix-scale, which led to longitudinal stretching of cells, increased cell aspect ratio, and enormous volumetric compression of the PCM. These experimental results are corroborated by a finite element model, which further demonstrated that impingement produces high cell surface stresses and strains that greatly exceed those brought about by longitudinal tension. Moreover, in both experiments and simulations, impingement-generated microscale stresses and strains are highly dependent on initial cell-cell gap spacing. Identifying factors that influence the microscale strain environment generated by impingement could contribute to a more mechanistic understanding of impingement-induced tendinopathies.

3.
BMC Cardiovasc Disord ; 24(1): 343, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969974

RESUMO

BACKGROUND: Heart failure (HF) with preserved or mildly reduced ejection fraction includes a heterogenous group of patients. Reclassification into distinct phenogroups to enable targeted interventions is a priority. This study aimed to identify distinct phenogroups, and compare phenogroup characteristics and outcomes, from electronic health record data. METHODS: 2,187 patients admitted to five UK hospitals with a diagnosis of HF and a left ventricular ejection fraction ≥ 40% were identified from the NIHR Health Informatics Collaborative database. Partition-based, model-based, and density-based machine learning clustering techniques were applied. Cox Proportional Hazards and Fine-Gray competing risks models were used to compare outcomes (all-cause mortality and hospitalisation for HF) across phenogroups. RESULTS: Three phenogroups were identified: (1) Younger, predominantly female patients with high prevalence of cardiometabolic and coronary disease; (2) More frail patients, with higher rates of lung disease and atrial fibrillation; (3) Patients characterised by systemic inflammation and high rates of diabetes and renal dysfunction. Survival profiles were distinct, with an increasing risk of all-cause mortality from phenogroups 1 to 3 (p < 0.001). Phenogroup membership significantly improved survival prediction compared to conventional factors. Phenogroups were not predictive of hospitalisation for HF. CONCLUSIONS: Applying unsupervised machine learning to routinely collected electronic health record data identified phenogroups with distinct clinical characteristics and unique survival profiles.


Assuntos
Registros Eletrônicos de Saúde , Insuficiência Cardíaca , Volume Sistólico , Função Ventricular Esquerda , Humanos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Medição de Risco , Reino Unido/epidemiologia , Fatores de Risco , Prognóstico , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Aprendizado de Máquina não Supervisionado , Hospitalização , Fatores de Tempo , Comorbidade , Causas de Morte , Fenótipo , Mineração de Dados
4.
Angew Chem Int Ed Engl ; : e202404452, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38959334

RESUMO

Hydrogen-bonded organic frameworks (HOFs) are a new class of crystalline porous organic molecular materials (POMMs) with great potential for a diverse range of applications. HOFs face common challenges to POMMs, and in general to purely organic crystals, that is, the difficulty of integrating complexity in crystals. Herein, we proposed a simple and sequential strategy for the formation of HOFs with hierarchical superstructures. The strategy is based on controlling the assembly conditions, avoiding the use of any surface functionalization or template, which allows to obtain hierarchical crystalline porous superstructures in an easy manner. As proof of concept, we obtained the first example of core-shell (HOF-on-HOF) crystals and HOFs with hierarchical superstructures having superhydrophobicity and trapping abilities for the capture of persistent water contaminants such as oils and microplastics. We expect that this strategy could serve as inspiration for the construction of more intricated multiscale structures that could greatly expand the library of HOFs materials.

5.
Ecol Evol ; 14(7): e11649, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38952663

RESUMO

Drylands are unique among terrestrial ecosystems in that they have a significant proportion of primary production facilitated by non-vascular plants such as colonial cyanobacteria, moss, and lichens, i.e., biocrusts, which occur on and in the surface soil. Biocrusts inhabit all continents, including Antarctica, an increasingly dynamic continent on the precipice of change. Here, we describe in-situ field surveying and sampling, remote sensing, and modeling approaches to assess the habitat suitability of biocrusts in the Lake Fryxell basin of Taylor Valley, Antarctica, which is the main site of the McMurdo Dry Valleys Long-Term Ecological Research Program. Soils suitable for the development of biocrusts are typically wetter, less alkaline, and less saline compared to unvegetated soils. Using random forest models, we show that gravimetric water content, electrical conductivity, and snow frequency are the top predictors of biocrust presence and biomass. Areas most suitable for the growth of dense biocrusts are soils associated with seasonal snow patches. Using geospatial data to extrapolate our habitat suitability model to the whole basin predicts that biocrusts are present in 2.7 × 105 m2 and contain 11-72 Mg of aboveground carbon, based on the 90% probability of occurrence. Our study illustrates the synergistic effect of combining field and remote sensing data for understanding the distribution and biomass of biocrusts, a foundational community in the carbon balance of this region. Extreme weather events and changing climate conditions in this region, especially those influencing snow accumulation and persistence, could have significant effects on the future distribution and abundance of biocrusts and therefore soil organic carbon storage in the McMurdo Dry Valleys.

6.
Chemistry ; : e202401446, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958604

RESUMO

Life on Earth uses DNA as the central template for self-replication, genetic encoding, and information transfer. However, there are no physical laws precluding life's existence elsewhere in space, and alternative life forms may not need DNA. In the search for exobiology, knowing what to look for as a biosignature remains a challenge-especially if it is not from the obvious list of biologic building blocks. Clues from chemicals recently discovered on Mars and in the Taurus Molecular Cloud 1 (TMC-1), show that intriguing organic compounds exist beyond Earth, which could provide a starting point for unconventional exobiotic designs. Here we present a new self-replicating system with structural similarities to recently discovered compounds on Mars and TMC-1. Rather than using DNA's hydrogen-bonding motif for reliable base-paring, our design employs sulfur-nitrogen interactions to selectively template unique benzothiadiazole units in sequence. We synthesized and studied two versions of this system, one reversible and the other irreversible, and found experimental evidence of self-replication in d-chloroform solvent. These results are part of a larger pursuit in our lab for developing a basis for a potential exobiological system using starting blocks closely related to these cosmic compounds.

8.
Cell Rep Med ; 5(7): 101654, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39019011

RESUMO

Plasmodium falciparum reticulocyte-binding protein homolog 5 (RH5) is a leading blood-stage malaria vaccine antigen target, currently in a phase 2b clinical trial as a full-length soluble protein/adjuvant vaccine candidate called RH5.1/Matrix-M. We identify that disordered regions of the full-length RH5 molecule induce non-growth inhibitory antibodies in human vaccinees and that a re-engineered and stabilized immunogen (including just the alpha-helical core of RH5) induces a qualitatively superior growth inhibitory antibody response in rats vaccinated with this protein formulated in Matrix-M adjuvant. In parallel, bioconjugation of this immunogen, termed "RH5.2," to hepatitis B surface antigen virus-like particles (VLPs) using the "plug-and-display" SpyTag-SpyCatcher platform technology also enables superior quantitative antibody immunogenicity over soluble protein/adjuvant in vaccinated mice and rats. These studies identify a blood-stage malaria vaccine candidate that may improve upon the current leading soluble protein vaccine candidate RH5.1/Matrix-M. The RH5.2-VLP/Matrix-M vaccine candidate is now under evaluation in phase 1a/b clinical trials.


Assuntos
Anticorpos Antiprotozoários , Vacinas Antimaláricas , Plasmodium falciparum , Proteínas de Protozoários , Vacinas de Partículas Semelhantes a Vírus , Animais , Vacinas Antimaláricas/imunologia , Anticorpos Antiprotozoários/imunologia , Plasmodium falciparum/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Humanos , Camundongos , Proteínas de Protozoários/imunologia , Ratos , Malária Falciparum/prevenção & controle , Malária Falciparum/imunologia , Antígenos de Protozoários/imunologia , Feminino , Proteínas de Transporte/imunologia , Camundongos Endogâmicos BALB C
10.
Nature ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020171

RESUMO

Giant exoplanets orbiting close to their host stars are unlikely to have formed in their present configurations1. These 'hot Jupiter' planets are instead thought to have migrated inward from beyond the ice line and several viable migration channels have been proposed, including eccentricity excitation through angular-momentum exchange with a third body followed by tidally driven orbital circularization2,3. The discovery of the extremely eccentric (e = 0.93) giant exoplanet HD 80606 b (ref. 4) provided observational evidence that hot Jupiters may have formed through this high-eccentricity tidal-migration pathway5. However, no similar hot-Jupiter progenitors have been found and simulations predict that one factor affecting the efficacy of this mechanism is exoplanet mass, as low-mass planets are more likely to be tidally disrupted during periastron passage6-8. Here we present spectroscopic and photometric observations of TIC 241249530 b, a high-mass, transiting warm Jupiter with an extreme orbital eccentricity of e = 0.94. The orbit of TIC 241249530 b is consistent with a history of eccentricity oscillations and a future tidal circularization trajectory. Our analysis of the mass and eccentricity distributions of the transiting-warm-Jupiter population further reveals a correlation between high mass and high eccentricity.

11.
Clin Neuroradiol ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023541

RESUMO

BACKGROUND: The comparative efficacy and safety of first-generation flow diverters (FDs), Pipeline Embolization Device (PED) (Medtronic, Irvine, California), Silk (Balt Extrusion, Montmorency, France), Flow Re-direction Endoluminal Device (FRED) (Microvention, Tustin, California), and Surpass Streamline (Stryker Neurovascular, Fremont, California), is not directly established and largely inferred. PURPOSE: This study aimed to compare the efficacy of different FDs in treating sidewall ICA intracranial aneurysms. METHODS: We conducted a retrospective review of prospectively maintained databases from eighteen academic institutions from 2009-2016, comprising 444 patients treated with one of four devices for sidewall ICA aneurysms. Data on demographics, aneurysm characteristics, treatment outcomes, and complications were analyzed. Angiographic and clinical outcomes were assessed using various imaging modalities and modified Rankin Scale (mRS). Propensity score weighting was employed to balance confounding variables. The data analysis used Kaplan-Meier curves, logistic regression, and Cox proportional-hazards regression. RESULTS: While there were no significant differences in retreatment rates, functional outcomes (mRS 0-1), and thromboembolic complications between the four devices, the probability of achieving adequate occlusion at the last follow-up was highest in Surpass device (HR: 4.59; CI: 2.75-7.66, p < 0.001), followed by FRED (HR: 2.23; CI: 1.44-3.46, p < 0.001), PED (HR: 1.72; CI: 1.10-2.70, p = 0.018), and Silk (HR: 1.0 ref. standard). The only hemorrhagic complications were with Surpass (1%). CONCLUSION: All the first-generation devices achieved good clinical outcomes and retreatment rates in treating ICA sidewall aneurysms. Prospective studies are needed to explore the nuanced differences between these devices in the long term.

12.
J Anim Ecol ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016072

RESUMO

Seasonal variability in environmental conditions is a strong determinant of animal migrations, but warming temperatures associated with climate change are anticipated to alter this phenomenon with unknown consequences. We used a 40-year fishery-independent survey to assess how a changing climate has altered the migration timing, duration and first-year survival of juvenile bull sharks (Carcharhinus leucas). From 1982 to 2021, estuaries in the western Gulf of Mexico (Texas) experienced a mean increase of 1.55°C in autumn water temperatures, and delays in autumn cold fronts by ca. 0.5 days per year. Bull shark migrations in more northern estuaries concomitantly changed, with departures 25-36 days later in 2021 than in 1982. Later, migrations resulted in reduced overwintering durations by up to 81 days, and the relative abundance of post-overwintering age 0-1 sharks increased by >50% during the 40-year study period. Yet, reductions in prey availability were the most influential factor delaying migrations. Juvenile sharks remained in natal estuaries longer when prey were less abundant. Long-term declines in prey reportedly occurred due to reduced spawning success associated with climate change based on published reports. Consequently, warming waters likely enabled and indirectly caused the observed changes in shark migratory behaviour. As water temperatures continue to rise, bull sharks in the north-western Gulf of Mexico could forgo their winter migrations in the next 50-100 years based on current trends and physiological limits, thereby altering their ecological roles in estuarine ecosystems and recruitment into the adult population. It is unclear if estuarine food webs will be able to support changing residency patterns as climate change affects the spawning success of forage species. We expect these trends are not unique to the western Gulf of Mexico or bull sharks, and migratory patterns of predators in subtropical latitudes are similarly changing at a global scale.

13.
J Med Genet ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38977299

RESUMO

OBJECTIVE: This study aims to develop and internally validate a clinical risk score to predict incident renal angiomyolipoma (AML) and pulmonary lymphangioleiomyomatosis (LAM) in people with tuberous sclerosis complex (TSC). STUDY DESIGN: Data from 2420 participants in the TSC Alliance Natural History Database were leveraged for these analyses. Logistic regression was used to predict AML and LAM development using 10 early-onset clinical manifestations of TSC as potential predictors, in addition to sex and genetic mutation. For our models, we divided AML into three separate outcomes: presence or absence of AML, unilateral or bilateral and whether any are ≥3 cm in diameter. The resulting regression models were turned into clinical risk scores which were then internally validated using bootstrap resampling, measuring discrimination and calibration. RESULTS: The lowest clinical risk scores predicted a risk of AML and LAM of 1% and 0%, while the highest scores predicted a risk of 99% and 73%, respectively. Calibration was excellent for all three AML outcomes and good for LAM. Discrimination ranged from good to strong. C-statistics of 0.84, 0.83, 0.83 and 0.92 were seen for AML, bilateral AML, AML with a lesion≥3 cm and LAM, respectively. CONCLUSION: Our work is an important step towards identifying individuals who could benefit from preventative strategies as well as more versus less frequent screening imaging. We expect that our work will allow for more personalised medicine in people with TSC. External validation of the risk scores will be important to confirm the robustness of our findings.

14.
Microbiol Spectr ; : e0324023, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012116

RESUMO

Bacterial species often consist of strains with variable gene content, collectively referred to as the pangenome. Variations in the genetic makeup of strains can alter bacterial physiology and fitness. To define biologically relevant genes of a genome, genome-wide transposon mutant libraries have been used to identify genes essential for survival or virulence in a given strain. Such phenotypic studies have been conducted in four different genotypes of the human pathogen Streptococcus pyogenes, yet challenges exist in comparing results across studies conducted in different genetic backgrounds and conditions. To advance genotype to phenotype inferences across different S. pyogenes strains, we built a pangenome database of 249 S. pyogenes reference genomes. We systematically re-analyzed publicly available transposon sequencing datasets from S. pyogenes using a transposon sequencing-specific analysis pipeline, Transit. Across four genetic backgrounds and nine phenotypic conditions, 355 genes were essential for survival, corresponding to ~24% of the core genome. Clusters of Orthologous Genes (COG) categories related to coenzyme and lipid transport and growth functions were overrepresented as essential. Finally, essential operons across S. pyogenes genotypes were defined, with an increased number of essential operons detected under in vivo conditions. This study provides an extendible database to which new studies can be added, and a searchable html-based resource to direct future investigations into S. pyogenes biology.IMPORTANCEStreptococcus pyogenes is a human-adapted pathogen occupying restricted ecological niches. Understanding the essentiality of genes across different strains and experimental conditions is important to direct research questions and efforts to prevent the large burden of disease caused by S. pyogenes. To this end we systematically reanalyzed transposon sequencing studies in S. pyogenes using transposon sequencing-specific methods, integrating them into an extendible meta-analysis framework. This provides a repository of gene essentiality in S. pyogenes which was used to highlight specific genes of interest and for the community to guide future phenotypic studies.

15.
J Orthop Trauma ; 38(8): e307-e311, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39007668

RESUMO

OBJECTIVE: The objective of this study was to compare the quality of syndesmotic reduction with the ankle in maximal dorsiflexion versus neutral plantarflexion (normal resting position). METHODS: Baseline computed tomography (CT) imaging of 10 cadaveric ankle specimens from 5 donors was obtained with the ankles placed in normal resting position. Two fellowship-trained orthopaedic surgeons disrupted the syndesmosis of each ankle specimen. All ankles were then placed in neutral plantarflexion and were subsequently reduced with thumb pressure under direct visualization through an anterolateral approach and stabilized with one 0.062-inch K-wire placed from lateral to medial in a quadricortical fashion across the syndesmosis. Postreduction CT scans were then obtained with the ankle in normal resting position. This process was repeated with the ankles placed in maximal dorsiflexion during reduction and stabilization. Postreduction CT scans were then obtained with the ankles placed in normal resting position. All postreduction CT scans were compared with baseline CT imaging using mixed-effects linear regression with significance set at P < 0.05. RESULTS: Syndesmotic reduction and stabilization in maximal dorsiflexion led to increased external rotation of the fibula compared with baseline scans [13.0 ± 5.4 degrees (mean ± SD) vs. 7.5 ± 2.4 degrees, P = 0.002]. There was a tendency toward lateral translation of the fibula with the ankle reduced in maximal dorsiflexion (3.3 ± 1.0 vs. 2.7 ± 0.7 mm, P = 0.096). No other statistically significant differences between measurements of reduction with the ankle placed in neutral plantarflexion or maximal dorsiflexion compared with baseline were present (P > 0.05). CONCLUSIONS: Reducing the syndesmosis with the ankle in maximal dorsiflexion may lead to malreduction with external rotation of the fibula. There was no statistically significant difference in reduction quality with the ankle placed in neutral plantarflexion compared with baseline. Future studies should assess the clinical implications of ankle positioning during syndesmotic fixation.


Assuntos
Articulação do Tornozelo , Cadáver , Humanos , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Articulação do Tornozelo/anatomia & histologia , Articulação do Tornozelo/fisiologia , Traumatismos do Tornozelo/cirurgia , Traumatismos do Tornozelo/diagnóstico por imagem , Masculino , Posicionamento do Paciente , Feminino , Fraturas do Tornozelo/cirurgia , Fraturas do Tornozelo/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Pessoa de Meia-Idade , Fixação Interna de Fraturas/métodos , Amplitude de Movimento Articular/fisiologia
16.
Methods Mol Biol ; 2829: 127-156, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38951331

RESUMO

The baculovirus expression vector system (BEVS) has now found acceptance in both research laboratories and industry, which can be attributed to many of its key features including the limited host range of the vectors, their non-pathogenicity to humans, and the mammalian-like post-translational modification (PTMs) that can be achieved in insect cells. In fact, this system acts as a middle ground between prokaryotes and higher eukaryotes to produce complex biologics. Still, industrial use of the BEVS lags compared to other platforms. We have postulated that one reason for this has been a lack of genetic tools that can complement the study of baculovirus vectors, while a second reason is the co-production of the baculovirus vector with the desired product. While some genetic enhancements have been made to improve the BEVS as a production platform, the genome remains under-scrutinized. This chapter outlines the methodology for a CRISPR-Cas9-based transfection-infection assay to probe the baculovirus genome for essential/nonessential genes that can potentially maximize foreign gene expression under a promoter of choice.


Assuntos
Baculoviridae , Sistemas CRISPR-Cas , Vetores Genéticos , Baculoviridae/genética , Vetores Genéticos/genética , Animais , Genes Essenciais , Expressão Gênica , Transfecção/métodos , Edição de Genes/métodos , Células Sf9 , Humanos
17.
bioRxiv ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38948786

RESUMO

Liprin-α1 is a widely expressed scaffolding protein responsible for regulating cellular processes such as focal adhesion, cell motility, and synaptic transmission. Liprin-α1 interacts with many proteins including ELKS, GIT1, liprin-ß, and LAR-family receptor tyrosine protein phosphatase. Through these protein-protein interactions, liprin-α1 assembles large higher-order molecular complexes; however, the regulation of this complex assembly/disassembly is unknown. Liquid-liquid phase separation (LLPS) is a process that concentrates proteins within cellular nano-domains to facilitate efficient spatiotemporal signaling in response to signaling cascades. While there is no report that liprin-α1 spontaneously undergoes LLPS, we found that GFP-liprin-α1 expressed in HEK293 cells occasionally forms droplet-like condensates. MS-based interactomics identified Protein Phosphatase 2A (PP2A)/B56δ (PPP2R5D) trimers as specific interaction partners of liprin-α1 through a canonical Short Linear Interaction Motif (SLiM) in its N-terminal dimerization domain. Mutation of this SLiM nearly abolished PP2A interaction, and resulted in significantly increased LLPS. GFP-liprin-α1 showed significantly increased droplet formation in HEK293 cells devoid of B56δ (PPP2R5D knockout), suggesting that PPP2R5D/PP2A holoenzyme inhibits liprin-α1 LLPS. Guided by reported liprin-α1 Ser/Thr phosphorylation sites, we found liprin-α1 phospho-mimetic mutant at serine 763 (S763E) is sufficient to drive its LLPS. Domain mapping studies of liprin-α1 indicated that the intrinsically disordered region, the N-terminal dimerization domain, and the SAM domains are all necessary for liprin-α1 LLPS. Finally, expression of p.E420K, a human PPP2R5D variant causing Houge-Janssens Syndrome type 1 (also known as Jordan's Syndrome), significantly compromised suppression of liprin-α1 LLPS. Our work identified B56δ-PP2A holoenzyme as an inhibitor of liprin-α1 LLPS via regulation at multiple phosphorylation sites.

18.
FEBS J ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38975872

RESUMO

Immunomodulatory imide drugs (IMiDs) are central components of therapy for multiple myeloma (MM). IMiDs bind cereblon (CRBN), an adaptor for the CUL4-DDB1-RBX1 E3 ligase to change its substrate specificity and induce degradation of 'neosubstrate' transcription factors that are essential to MM cells. Mechanistic studies to date have largely focussed on mediators of therapeutic activity and insight into clinical IMiD toxicities is less developed. We adopted BioID2-dependent proximity labelling (BioID2-CRBN) to characterise the CRBN interactome in the presence and absence of various IMiDs and the proteasome inhibitor, bortezomib. We aimed to leverage this technology to further map CRBN interactions beyond what has been achieved by conventional proteomic techniques. In support of this approach, analysis of cells expressing BioID2-CRBN following IMiD treatment displayed biotinylation of known CRBN interactors and neosubstrates. We observed that bortezomib alone significantly modifies the CRBN interactome. Proximity labelling also suggested that IMiDs augment the interaction between CRBN and proteins that are not degraded, thus designating 'neointeractors' distinct from previously disclosed 'neosubstrates'. Here we identify Non-Muscle Myosin Heavy Chain IIA (MYH9) as a putative CRBN neointeractor that may contribute to the haematological toxicity of IMiDs. These studies provide proof of concept for proximity labelling technologies in the mechanistic profiling of IMiDs and related E3-ligase-modulating drugs.

19.
JAMA Cardiol ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958943

RESUMO

Importance: There is no consensus regarding the best method for prediction of hypertensive disorders of pregnancy (HDP), including gestational hypertension and preeclampsia. Objective: To determine predictive ability in early pregnancy of large-scale proteomics for prediction of HDP. Design, Setting, and Participants: This was a nested case-control study, conducted in 2022 to 2023, using clinical data and plasma samples collected between 2010 and 2013 during the first trimester, with follow-up until pregnancy outcome. This multicenter observational study took place at 8 academic medical centers in the US. Nulliparous individuals during first-trimester clinical visits were included. Participants with HDP were selected as cases; controls were selected from those who delivered at or after 37 weeks without any HDP, preterm birth, or small-for-gestational-age infant. Age, self-reported race and ethnicity, body mass index, diabetes, health insurance, and fetal sex were available covariates. Exposures: Proteomics using an aptamer-based assay that included 6481 unique human proteins was performed on stored plasma. Covariates were used in predictive models. Main Outcomes and Measures: Prediction models were developed using the elastic net, and analyses were performed on a randomly partitioned training dataset comprising 80% of study participants, with the remaining 20% used as an independent testing dataset. Primary measure of predictive performance was area under the receiver operating characteristic curve (AUC). Results: This study included 753 HDP cases and 1097 controls with a mean (SD) age of 26.9 (5.5) years. Maternal race and ethnicity were 51 Asian (2.8%), 275 non-Hispanic Black (14.9%), 275 Hispanic (14.9%), 1161 non-Hispanic White (62.8% ), and 88 recorded as other (4.8%), which included those who did not identify according to these designations. The elastic net model, allowing for forced inclusion of prespecified covariates, was used to adjust protein-based models for clinical and demographic variables. Under this approach, no proteins were selected to augment the clinical and demographic covariates. The predictive performance of the resulting model was modest, with a training set AUC of 0.64 (95% CI, 0.61-0.67) and a test set AUC of 0.62 (95% CI, 0.56-0.68). Further adjustment for study site yielded only minimal changes in AUCs. Conclusions and Relevance: In this case-control study with detailed clinical data and stored plasma samples available in the first trimester, an aptamer-based proteomics panel did not meaningfully add to predictive utility over and above clinical and demographic factors that are routinely available.

20.
Adv Sci (Weinh) ; : e2402757, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041892

RESUMO

Desmoplasia in breast cancer leads to heterogeneity in physical properties of the tissue, resulting in disparities in drug delivery and treatment efficacy among patients, thus contributing to high disease mortality. Personalized in vitro breast cancer models hold great promise for high-throughput testing of therapeutic strategies to normalize the aberrant microenvironment in a patient-specific manner. Here, tumoroids assembled from breast cancer cell lines (MCF7, SKBR3, and MDA-MB-468) and patient-derived breast tumor cells (TCs) cultured in microphysiological systems including perfusable microvasculature reproduce key aspects of stromal and vascular dysfunction causing impaired drug delivery. Models containing SKBR3 and MDA-MB-468 tumoroids show higher stromal hyaluronic acid (HA) deposition, vascular permeability, interstitial fluid pressure (IFP), and degradation of vascular HA relative to models containing MCF7 tumoroids or models without tumoroids. Interleukin 8 (IL8) secretion is found responsible for vascular dysfunction and loss of vascular HA. Interventions targeting IL8 or stromal HA normalize vascular permeability, perfusion, and IFP, and ultimately enhance drug delivery and TC death in response to perfusion with trastuzumab and cetuximab. Similar responses are observed in patient-derived models. These microphysiological systems can thus be personalized by using patient-derived cells and can be applied to discover new molecular therapies for the normalization of the tumor microenvironment.

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