357 research outputs found
Synthesis of Newly Formulated Aluminium Composite through Powder Metallurgy using Waste Bone Material
The increasing concern for sustainable materials and waste management has led to innovative approaches in material science. This study explores the potential benefit of aggregate waste in the production of aluminum composites practicing powder metallurgy techniques. The aim is to investigate the feasibility of incorporating bone material into aluminium matrices to enhance the composite’s mechanical properties. The research involves several key steps. Firstly, waste bone material is collected and processed to obtain a fine powder suitable for powder metallurgy. Various techniques such as grinding, milling, or pulverization are employed to achieve the desired particle size distribution. Next, the bone powder is mixed with aluminium powder in predetermined ratios to create composite blends. The composite blends are then subjected to compaction using powder metallurgy techniques, including cold pressing and sintering. The compaction process aims to consolidate the powders and facilitate the formation of a solid composite structure. The aluminum composites mechanical characteristics are then assessed. The effects of incorporating bone material are assessed using tests on tensile strength, ductility, hardness, and other relevant mechanical properties. Comparative analysis is performed between the composites with bone material and traditional aluminium composites to assess any improvements or changes in performance
Targeting of aberrant αvβ6 integrin expression in solid tumors using chimeric antigen receptor-engineered T-cells
Expression of the αvβ6 integrin is upregulated in several solid tumors. By contrast, physiologic expression of this epithelial-specific integrin is restricted to development and epithelial re-modeling. Here, we describe for the first time the development of a chimeric antigen receptor (CAR) that couples the recognition of this integrin to the delivery of potent therapeutic activity in a diverse repertoire of solid tumor models. Highly selective targeting of αvβ6 was achieved using a foot and mouth disease virus-derived A20 peptide, coupled to a fused CD28+CD3 endodomain. To achieve selective expansion of CAR T-cells ex vivo, an IL-4-responsive fusion gene (4αβ) was co-expressed which delivers a selective mitogenic signal to engineered T-cells only. In vivo efficacy was demonstrated in mice with established ovarian, breast and pancreatic tumor xenografts, all of which express αvβ6 at intermediate to high levels. SCID Beige mice were used for these studies since they are susceptible to cytokine release syndrome, unlike more immune compromised strains. Nonetheless, although the CAR also engages mouse αvβ6, mild and reversible toxicity was only observed when supra-therapeutic doses of CAR T-cells were administered parenterally. These data support the clinical evaluation of αvβ6 re-targeted CAR T-cell immunotherapy in solid tumors that express this integrin.<br/
Impact of Baseline Steroids on Efficacy of Programmed Cell Death-1 and Programmed Death-Ligand 1 Blockade in Patients With Non-Small-Cell Lung Cancer
Treatment with programmed cell death-1 or programmed death ligand 1 (PD-(L)1) inhibitors is now standard therapy for patients with lung cancer. The immunosuppressive effect of corticosteroids may reduce efficacy of PD-(L)1 blockade. On-treatment corticosteroids for treatment of immune-related adverse events do not seem to affect efficacy, but the potential impact of baseline corticosteroids at the time of treatment initiation is unknown. Clinical trials typically excluded patients who received baseline corticosteroids, which led us to use real-world data to examine the effect of corticosteroids at treatment initiation. We identified patients who were PD-(L)1-naïve with advanced non-small-cell lung cancer from two institutions-Memorial Sloan Kettering Cancer Center and Gustave Roussy Cancer Center-who were treated with single-agent PD-(L)1 blockade. Clinical and pharmacy records were reviewed to identify corticosteroid use at the time of beginning anti-PD-(L)1 therapy. We performed multivariable analyses using Cox proportional hazards regression model and logistic regression. Ninety (14%) of 640 patients treated with single-agent PD-(L)1 blockade received corticosteroids of ≥ 10 mg of prednisone equivalent daily at the start of the PD-(L)1 blockade. Common indications for corticosteroids were dyspnea (33%), fatigue (21%), and brain metastases (19%). In both independent cohorts, Memorial Sloan Kettering Cancer Center (n = 455) and Gustave Roussy Cancer Center (n = 185), baseline corticosteroids were associated with decreased overall response rate, progression-free survival, and overall survival with PD-(L)1 blockade. In a multivariable analysis of the pooled population, adjusting for smoking history, performance status, and history of brain metastases, baseline corticosteroids remained significantly associated with decreased progression-free survival (hazard ratio, 1.3; P = .03), and overall survival (hazard ratio, 1.7; P Baseline corticosteroid use of ≥ 10 mg of prednisone equivalent was associated with poorer outcome in patients with non-small-cell lung cancer who were treated with PD-(L)1 blockade. Prudent use of corticosteroids at the time of initiating PD-(L)1 blockade is recommended
Pol II phosphorylation regulates a switch between transcriptional and splicing condensates
The synthesis of pre-mRNA by RNA polymerase II (Pol II) involves the formation of a transcription initiation complex, and a transition to an elongation complex. The large subunit of Pol II contains an intrinsically disordered C-terminal domain that is phosphorylated by cyclin-dependent kinases during the transition from initiation to elongation, thus influencing the interaction of the C-terminal domain with different components of the initiation or the RNA-splicing apparatus. Recent observations suggest that this model provides only a partial picture of the effects of phosphorylation of the C-terminal domain. Both the transcription-initiation machinery and the splicing machinery can form phase-separated condensates that contain large numbers of component molecules: hundreds of molecules of Pol II and mediator are concentrated in condensates at super-enhancers, and large numbers of splicing factors are concentrated in nuclear speckles, some of which occur at highly active transcription sites. Here we investigate whether the phosphorylation of the Pol II C-terminal domain regulates the incorporation of Pol II into phase-separated condensates that are associated with transcription initiation and splicing. We find that the hypophosphorylated C-terminal domain of Pol II is incorporated into mediator condensates and that phosphorylation by regulatory cyclin-dependent kinases reduces this incorporation. We also find that the hyperphosphorylated C-terminal domain is preferentially incorporated into condensates that are formed by splicing factors. These results suggest that phosphorylation of the Pol II C-terminal domain drives an exchange from condensates that are involved in transcription initiation to those that are involved in RNA processing, and implicates phosphorylation as a mechanism that regulates condensate preference
Mediator Condensates Localize Signaling Factors to Key Cell Identity Genes
The gene expression programs that define the identity of each cell are controlled by master transcription factors (TFs) that bind cell-type-specific enhancers, as well as signaling factors, which bring extracellular stimuli to these enhancers. Recent studies have revealed that master TFs form phase-separated condensates with the Mediator coactivator at super-enhancers. Here, we present evidence that signaling factors for the WNT, TGF-β, and JAK/STAT pathways use their intrinsically disordered regions (IDRs) to enter and concentrate in Mediator condensates at super-enhancers. We show that the WNT coactivator β-catenin interacts both with components of condensates and DNA-binding factors to selectively occupy super-enhancer-associated genes. We propose that the cell-type specificity of the response to signaling is mediated in part by the IDRs of the signaling factors, which cause these factors to partition into condensates established by the master TFs and Mediator at genes with prominent roles in cell identity
Proceedings of the 1st Biannual Bridging the Gaps in Lung Cancer Conference
Lung cancer is the leading cause of cancer death in the US and globally. The mortality from lung cancer has been declining, due to a reduction in incidence and advances in treatment. Although recent success in developing targeted and immunotherapies for lung cancer has benefitted patients, it has also expanded the complexity of potential treatment options for health care providers. To aid in reducing such complexity, experts in oncology convened a conference (Bridging the Gaps in Lung Cancer) to identify current knowledge gaps and controversies in the diagnosis, treatment, and outcomes of various lung cancer scenarios, as described here. Such scenarios relate to biomarkers and testing in lung cancer, small cell lung cancer, EGFR mutations and targeted therapy in non-small cell lung cancer (NSCLC), early-stage NSCLC, KRAS/BRAF/MET and other genomic alterations in NSCLC, and immunotherapy in advanced NSCLC
Coactivator condensation at super-enhancers links phase separation and gene control
Super-enhancers (SEs) are clusters of enhancers that cooperatively assemble a high density of the transcriptional apparatus to drive robust expression of genes with prominent roles in cell identity. Here we demonstrate that the SE-enriched transcriptional coactivators BRD4 and MED1 form nuclear puncta at SEs that exhibit properties of liquid-like condensates and are disrupted by chemicals that perturb condensates. The intrinsically disordered regions (IDRs) of BRD4 and MED1 can form phase-separated droplets, and MED1-IDR droplets can compartmentalize and concentrate the transcription apparatus from nuclear extracts. These results support the idea that coactivators form phase-separated condensates at SEs that compartmentalize and concentrate the transcription apparatus, suggest a role for coactivator IDRs in this process, and offer insights into mechanisms involved in the control of key cell-identity genes
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