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1.
Angew Chem Int Ed Engl ; 63(18): e202400837, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38446007

RESUMEN

Magnesium batteries attract interest as alternative energy-storage devices because of elemental abundance and potential for high energy density. Development is limited by the absence of suitable cathodes, associated with poor diffusion kinetics resulting from strong interactions between Mg2+ and the host structure. V2PS10 is reported as a positive electrode material for rechargeable magnesium batteries. Cyclable capacity of 100 mAh g-1 is achieved with fast Mg2+ diffusion of 7.2 × ${\times }$ 10-11-4 × ${\times }$ 10-14 cm2 s-1. The fast insertion mechanism results from combined cationic redox on the V site and anionic redox on the (S2)2- site; enabled by reversible cleavage of S-S bonds, identified by X-ray photoelectron and X-ray absorption spectroscopy. Detailed structural characterisation with maximum entropy method analysis, supported by density functional theory and projected density of states analysis, reveals that the sulphur species involved in anion redox are not connected to the transition metal centres, spatially separating the two redox processes. This facilitates fast and reversible Mg insertion in which the nature of the redox process depends on the cation insertion site, creating a synergy between the occupancy of specific Mg sites and the location of the electrons transferred.

2.
Chem Commun (Camb) ; 59(85): 12767-12770, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37812072

RESUMEN

We use in situ neutron imaging to observe the adsorption/absorption of hydrogen within a packed catalyst bed of a Pd/C catalyst at a spatial and temporal resolution of ∼430 µm and a ∼9 s respectively. Additionally, the H2/D2 exchange process across the catalyst bed is followed in real time.

3.
Nurs Older People ; 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37221893

RESUMEN

It has been estimated that 70% of care home residents have dementia on admission or develop it after admission, but that many do not have or receive a formal diagnosis of dementia. People with dementia often have significant care needs and it is important that the condition is diagnosed even at an advanced stage. This will enable nurses to predict the person's care needs, develop appropriate care plans and arrange pre-emptive decisions. In 2021-22, a quality improvement project took place in care homes in West Norfolk. This project piloted an abbreviated memory assessment model based on the Diagnosing Advanced Dementia Mandate (DiADeM) tool to increase the rate of diagnoses among residents showing signs and symptoms of cognitive impairment but not formally diagnosed with dementia. Out of 109 residents assessed, 95 were diagnosed with dementia. The pilot is being extended locally and replicated across England.

4.
ACS Phys Chem Au ; 3(1): 74-83, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36718264

RESUMEN

This work investigates the acid sites in a commercial ZSM-5 zeolite catalyst by a combination of spectroscopic and physical methods. The Brønsted acid sites in such catalysts are associated with the aluminum substituted into the zeolite lattice, which may not be identical to the total aluminum content of the zeolite. Inelastic neutron scattering spectroscopy (INS) directly quantifies the concentrations of Brønsted acid protons, silanol groups, and hydroxyl groups associated with extra-framework aluminum species. The INS measurements show that ∼50% of the total aluminum content of this particular zeolite is extra framework, a conclusion supported by solid-state NMR and ammonia temperature-programmed desorption (TPD) measurements. Evidence for the presence of extra-framework aluminum oxide species is also seen in neutron powder diffraction data from proton- and deuterium-exchanged samples. The differences between results from the different analytical methods are discussed, and the novelty of direct proton counting by INS in this typical commercial catalyst is emphasized.

5.
J Chem Phys ; 157(18): 184702, 2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36379785

RESUMEN

Quasi-elastic neutron scattering (QENS) and molecular dynamics (MD) simulations are applied in combination to investigate the dynamics of methane in H-ZSM-5 zeolite catalysts used for methanol-to-hydrocarbons reactions. Methane is employed as an inert model for the methanol reaction feedstock, and studies are made of the fresh catalyst and used catalysts with varying levels of coke buildup to investigate the effect of coking on reactant mobility. Measurements are made in the temperature range from 5 to 373 K. Methane mobility under these conditions is found to be extremely high in fresh ZSM-5, with the majority of movements occurring too fast to be resolved by the QENS instrument used. A small fraction of molecules undergoing jump diffusion on QENS time scales is identified and found to correspond with short-range jump diffusion within single zeolite pores as identified in MD simulations. Agreement between QENS and MD mobility measurements is found to be within 50%, validating the simulation approach employed. Methane diffusion is found to be minimally affected by moderate levels of coke buildup, while highly coked samples result in the confinement of methane to single pores within the zeolite with minimal long-range diffusion.

6.
Sensors (Basel) ; 22(17)2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-36080876

RESUMEN

Ultrasound (US) image guidance is widely used for minimally invasive procedures, but the invasive medical devices (such as metallic needles), especially their tips, can be poorly visualised in US images, leading to significant complications. Photoacoustic (PA) imaging is promising for visualising invasive devices and peripheral tissue targets. Light-emitting diodes (LEDs) acting as PA excitation sources facilitate the clinical translation of PA imaging, but the image quality is degraded due to the low pulse energy leading to insufficient contrast with needles at deep locations. In this paper, photoacoustic visualisation of clinical needles was enhanced by elastomeric nanocomposite coatings with superficial and interstitial illumination. Candle soot nanoparticle-polydimethylsiloxane (CSNP-PDMS) composites with high optical absorption and large thermal expansion coefficients were applied onto the needle exterior and the end-face of an optical fibre placed in the needle lumen. The excitation light was delivered at the surface by LED arrays and through the embedded optical fibre by a pulsed diode laser to improve the visibility of the needle tip. The performance was validated using an ex-vivo tissue model. An LED-based PA/US imaging system was used for imaging the needle out-of-plane and in-plane insertions over approach angles of 20 deg to 55 deg. The CSNP-PDMS composite conferred substantial visual enhancements on both the needle shaft and the tip, with an average of 1.7- and 1.6-fold improvements in signal-to-noise ratios (SNRs), respectively. With the extended light field involving extracorporeal and interstitial illumination and the highly absorbing coatings, enhanced visualisation of the needle shaft and needle tip was achieved with PA imaging, which could be helpful in current US-guided minimally invasive surgeries.


Asunto(s)
Nanocompuestos , Agujas , Iluminación , Análisis Espectral , Ultrasonografía
7.
Nat Biotechnol ; 40(7): 1082-1092, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35256815

RESUMEN

Single-nuclei RNA sequencing characterizes cell types at the gene level. However, compared to single-cell approaches, many single-nuclei cDNAs are purely intronic, lack barcodes and hinder the study of isoforms. Here we present single-nuclei isoform RNA sequencing (SnISOr-Seq). Using microfluidics, PCR-based artifact removal, target enrichment and long-read sequencing, SnISOr-Seq increased barcoded, exon-spanning long reads 7.5-fold compared to naive long-read single-nuclei sequencing. We applied SnISOr-Seq to adult human frontal cortex and found that exons associated with autism exhibit coordinated and highly cell-type-specific inclusion. We found two distinct combination patterns: those distinguishing neural cell types, enriched in TSS-exon, exon-polyadenylation-site and non-adjacent exon pairs, and those with multiple configurations within one cell type, enriched in adjacent exon pairs. Finally, we observed that human-specific exons are almost as tightly coordinated as conserved exons, implying that coordination can be rapidly established during evolution. SnISOr-Seq enables cell-type-specific long-read isoform analysis in human brain and in any frozen or hard-to-dissociate sample.


Asunto(s)
Encéfalo , ARN , Empalme Alternativo/genética , Encéfalo/metabolismo , Exones/genética , Humanos , Isoformas de Proteínas/genética , ARN/genética , Análisis de Secuencia de ARN
8.
Sci Rep ; 12(1): 4369, 2022 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-35288582

RESUMEN

The zebra finch is one of the most commonly studied songbirds in biology, particularly in genomics, neuroscience and vocal communication. However, this species lacks a robust cell line for molecular biology research and reagent optimization. We generated a cell line, designated CFS414, from zebra finch embryonic fibroblasts using the SV40 large and small T antigens. This cell line demonstrates an improvement over previous songbird cell lines through continuous and density-independent growth, allowing for indefinite culture and monoclonal line derivation. Cytogenetic, genomic, and transcriptomic profiling established the provenance of this cell line and identified the expression of genes relevant to ongoing songbird research. Using this cell line, we disrupted endogenous gene sequences using S.aureus Cas9 and confirmed a stress-dependent localization response of a song system specialized gene, SAP30L. The utility of CFS414 cells enhances the comprehensive molecular potential of the zebra finch and validates cell immortalization strategies in a songbird species.


Asunto(s)
Pinzones , Animales , Sistemas CRISPR-Cas , Línea Celular , Pinzones/genética , Genoma , Genómica
9.
Mol Psychiatry ; 27(3): 1416-1434, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34789849

RESUMEN

Due to an inability to ethically access developing human brain tissue as well as identify prospective cases, early-arising neurodevelopmental and cell-specific signatures of Schizophrenia (Scz) have remained unknown and thus undefined. To overcome these challenges, we utilized patient-derived induced pluripotent stem cells (iPSCs) to generate 3D cerebral organoids to model neuropathology of Scz during this critical period. We discovered that Scz organoids exhibited ventricular neuropathology resulting in altered progenitor survival and disrupted neurogenesis. This ultimately yielded fewer neurons within developing cortical fields of Scz organoids. Single-cell sequencing revealed that Scz progenitors were specifically depleted of neuronal programming factors leading to a remodeling of cell-lineages, altered differentiation trajectories, and distorted cortical cell-type diversity. While Scz organoids were similar in their macromolecular diversity to organoids generated from healthy controls (Ctrls), four GWAS factors (PTN, COMT, PLCL1, and PODXL) and peptide fragments belonging to the POU-domain transcription factor family (e.g., POU3F2/BRN2) were altered. This revealed that Scz organoids principally differed not in their proteomic diversity, but specifically in their total quantity of disease and neurodevelopmental factors at the molecular level. Single-cell sequencing subsequently identified cell-type specific alterations in neuronal programming factors as well as a developmental switch in neurotrophic growth factor expression, indicating that Scz neuropathology can be encoded on a cell-type-by-cell-type basis. Furthermore, single-cell sequencing also specifically replicated the depletion of BRN2 (POU3F2) and PTN in both Scz progenitors and neurons. Subsequently, in two mechanistic rescue experiments we identified that the transcription factor BRN2 and growth factor PTN operate as mechanistic substrates of neurogenesis and cellular survival, respectively, in Scz organoids. Collectively, our work suggests that multiple mechanisms of Scz exist in patient-derived organoids, and that these disparate mechanisms converge upon primordial brain developmental pathways such as neuronal differentiation, survival, and growth factor support, which may amalgamate to elevate intrinsic risk of Scz.


Asunto(s)
Células Madre Pluripotentes Inducidas , Esquizofrenia , Humanos , Organoides/metabolismo , Proteómica , Esquizofrenia/metabolismo , Factores de Transcripción/metabolismo
10.
J Biochem ; 171(2): 187-199, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-34878535

RESUMEN

N-Glycanase 1 (NGLY1) deficiency is a rare and complex genetic disorder. Although recent studies have shed light on the molecular underpinnings of NGLY1 deficiency, a systematic characterization of gene and protein expression changes in patient-derived cells has been lacking. Here, we performed RNA-sequencing and mass spectrometry to determine the transcriptomes and proteomes of 66 cell lines representing four different cell types derived from 14 NGLY1 deficient patients and 17 controls. Although NGLY1 protein levels were up to 9.5-fold downregulated in patients compared with parents, residual and likely non-functional NGLY1 protein was detectable in all patient-derived lymphoblastoid cell lines. Consistent with the role of NGLY1 as a regulator of the transcription factor Nrf1, we observed a cell type-independent downregulation of proteasomal genes in NGLY1 deficient cells. In contrast, genes involved in ribosome biogenesis and mRNA processing were upregulated in multiple cell types. In addition, we observed cell type-specific effects. For example, genes and proteins involved in glutathione synthesis, such as the glutamate-cysteine ligase subunits GCLC and GCLM, were downregulated specifically in lymphoblastoid cells. We provide a web application that enables access to all results generated in this study at https://apps.embl.de/ngly1browser. This resource will guide future studies of NGLY1 deficiency in directions that are most relevant to patients.


Asunto(s)
Trastornos Congénitos de Glicosilación , Trastornos Congénitos de Glicosilación/genética , Trastornos Congénitos de Glicosilación/metabolismo , Regulación de la Expresión Génica , Humanos , Péptido-N4-(N-acetil-beta-glucosaminil) Asparagina Amidasa/deficiencia , Péptido-N4-(N-acetil-beta-glucosaminil) Asparagina Amidasa/genética , Péptido-N4-(N-acetil-beta-glucosaminil) Asparagina Amidasa/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo
11.
Adv Mater Interfaces ; 8(20): 2100518, 2021 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-34777946

RESUMEN

Dual-modality imaging employing complementary modalities, such as all-optical ultrasound and photoacoustic imaging, is emerging as a well-suited technique for guiding minimally invasive surgical procedures. Quantum dots are a promising material for use in these dual-modality imaging devices as they can provide wavelength-selective optical absorption. The first quantum dot nanocomposite engineered for co-registered laser-generated ultrasound and photoacoustic imaging is presented. The nanocomposites developed, comprising CuInS2 quantum dots and medical-grade polydimethylsiloxane (CIS-PDMS), are applied onto the distal ends of miniature optical fibers. The films exhibit wavelength-selective optical properties, with high optical absorption (> 90%) at 532 nm for ultrasound generation, and low optical absorption (< 5%) at near-infrared wavelengths greater than 700 nm. Under pulsed laser irradiation, the CIS-PDMS films generate ultrasound with pressures exceeding 3.5 MPa, with a corresponding bandwidth of 18 MHz. An ultrasound transducer is fabricated by pairing the coated optical fiber with a Fabry-Pérot (FP) fiber optic sensor. The wavelength-selective nature of the film is exploited to enable co-registered all-optical ultrasound and photoacoustic imaging of an ink-filled tube phantom. This work demonstrates the potential for quantum dots as wavelength-selective absorbers for all-optical ultrasound generation.

12.
J Phys Condens Matter ; 33(28)2021 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-33949972

RESUMEN

Platinum group metals such as palladium and rhodium based catalysts are currently being implemented in gasoline particulate filter (GPF) autoexhaust after treatment systems. However, little is known about how the trapped particulate matter, such as the incombustible ash, interacts with the catalyst and so may affect its performance. Thisoperandostudy follows the evolution of the Pd found in two different model GPF systems: one containing ash components extracted from a GPF and another from a catalyst washcoat prior to adhesion onto the GPF. We show that the catalytic activity of the two systems vary when compared with a 0 g ash containing GPF. Compared to the 0 g ash sample the 20 g ash containing sample had a higher CO light off temperature, in addition, an oscillation profile for CO, CO2and O2was observed, which is speculated to be a combination of CO oxidation, C deposition via a Boudouard reaction and further partial oxidation of the deposited species to CO. During the ageing procedure the washcoat sample reduces NO at a lower temperature than the 0 g ash sample. However, post ageing the 0 g ash sample recovers and both samples reduce NO at 310 °C. In comparison, the 20 g ash GPF sample maintains a higher NO reduction temperature of 410 °C post ageing, implying that the combination of high temperature ageing and presence of ash has an irreversible negative effect on catalyst performance.

13.
Nat Commun ; 12(1): 463, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33469025

RESUMEN

Splicing varies across brain regions, but the single-cell resolution of regional variation is unclear. We present a single-cell investigation of differential isoform expression (DIE) between brain regions using single-cell long-read sequencing in mouse hippocampus and prefrontal cortex in 45 cell types at postnatal day 7 ( www.isoformAtlas.com ). Isoform tests for DIE show better performance than exon tests. We detect hundreds of DIE events traceable to cell types, often corresponding to functionally distinct protein isoforms. Mostly, one cell type is responsible for brain-region specific DIE. However, for fewer genes, multiple cell types influence DIE. Thus, regional identity can, although rarely, override cell-type specificity. Cell types indigenous to one anatomic structure display distinctive DIE, e.g. the choroid plexus epithelium manifests distinct transcription-start-site usage. Spatial transcriptomics and long-read sequencing yield a spatially resolved splicing map. Our methods quantify isoform expression with cell-type and spatial resolution and it contributes to further our understanding of how the brain integrates molecular and cellular complexity.


Asunto(s)
Empalme Alternativo/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Hipocampo/metabolismo , Corteza Prefrontal/metabolismo , Isoformas de Proteínas/metabolismo , Animales , Animales Recién Nacidos , Biología Computacional , Femenino , Hipocampo/citología , Hipocampo/crecimiento & desarrollo , Ratones , Modelos Animales , Corteza Prefrontal/citología , Corteza Prefrontal/crecimiento & desarrollo , Isoformas de Proteínas/análisis , Isoformas de Proteínas/genética , Análisis de la Célula Individual/métodos , Análisis Espacial
14.
Angew Chem Int Ed Engl ; 60(10): 5125-5131, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33332715

RESUMEN

A multimodal imaging study of chabazite is used to show the distribution of and discriminate between different emissive deposits arising as a result of the detemplation process. Confocal imaging, 3D fluorescence lifetime imaging, 3D multispectral fluorescence imaging, and Raman mapping are used to show three different types of emissive behaviours each characterised by different spatial distributions, trends in lifetime, spectral signals, and Raman signatures. A notable difference is seen in the morphology of agglomerated surface deposits and larger subsurface deposits, which experience lifetime augmentation due to spatial confinement. The distribution of organic residue throughout the crystal volume is comparable to XRF mapping that shows Si enrichment on the outer edges and higher Al content through the centre, demonstrating that a fluorescence-based technique can also be used to indirectly comment on the compositional chemistry of the inorganic framework.

15.
Molecules ; 25(21)2020 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-33143211

RESUMEN

Small pore zeolites have shown great potential in a number of catalytic reactions. While Mo-containing medium pore zeolites have been widely studied for methane dehydroaromatisation (MDA), the use of small pore supports has drawn limited attention due to the fast deactivation of the catalyst. This work investigates the structure of the small pore Mo/H-SSZ-13 during catalyst preparation and reaction by operando X-ray absorption spectroscopy (XAS), in situ synchrotron powder diffraction (SPD), and electron microscopy; then, the results are compared with the medium pore Mo/H-ZSM-5. While SPD suggests that during catalyst preparation, part of the MoOx anchors inside the pores, Mo dispersion and subsequent ion exchange was less effective in the small pore catalyst, resulting in the formation of mesopores and Al2(MOO4)3 particles. Unlike Mo/H-ZSM-5, part of the Mo species in Mo/H-SSZ-13 undergoes full reduction to Mo0 during MDA, whereas characterisation of the spent catalyst indicates that differences also exist in the nature of the formed carbon deposits. Hence, the different Mo speciation and the low performance on small pore zeolites can be attributed to mesopores formation during calcination and the ineffective ion exchange into well dispersed Mo-oxo sites. The results open the scope for the optimisation of synthetic routes to explore the potential of small pore topologies.


Asunto(s)
Metano/química , Molibdeno/química , Zeolitas/química , Catálisis , Porosidad
16.
Phys Chem Chem Phys ; 22(34): 18774-18787, 2020 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-32602489

RESUMEN

The use of mechanochemistry to prepare catalytic materials is of significant interest; it offers an environmentally beneficial, solvent-free, route and produces highly complex structures of mixed amorphous and crystalline phases. This study reports on the effect of milling atmosphere, either air or argon, on mechanochemically prepared LaMnO3 and the catalytic performance towards N2O decomposition (deN2O). In this work, high energy resolution fluorescence detection (HERFD), X-ray absorption near edge structure (XANES), X-ray emission, and X-ray photoelectron spectroscopy (XPS) have been used to probe the electronic structural properties of the mechanochemically prepared materials. Moreover, in situ studies using near ambient pressure (NAP)-XPS, to follow the materials during catalysis, and high pressure energy dispersive EXAFS studies, to mimic the preparation conditions, have also been performed. The studies show that there are clear differences between the air and argon milled samples, with the most pronounced changes observed using NAP-XPS. The XPS results find increased levels of active adsorbed oxygen species, linked to the presence of surface oxide vacancies, for the sample prepared in argon. Furthermore, the argon milled LaMnO3 shows improved catalytic activity towards deN2O at lower temperatures compared to the air milled and sol-gel synthesised LaMnO3. Assessing this improved catalytic behaviour during deN2O of argon milled LaMnO3 by in situ NAP-XPS suggests increased interaction of N2O at room temperature within the O 1s region. This study further demonstrates the complexity of mechanochemically prepared materials and through careful choice of characterisation methods how their properties can be understood.

17.
Phys Chem Chem Phys ; 22(34): 18882-18890, 2020 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-32330216

RESUMEN

In situ studies on the physical and chemical properties of Au in inverse ceria alumina supported catalysts have been conducted between 295 and 623 K using high energy resolved fluorescence detection X-ray absorption near edge spectroscopy and X-ray total scattering. Precise structural information is extracted on the metallic Au phase present in a 0.85 wt% Au containing inverse ceria alumina catalyst (ceria/Au/alumina). Herein evidence for the formation of an Au hydride species at elevated temperature is presented. Through modelling of total scattering data to extract the thermal properties of Au using Grüneisen theory of volumetric thermal expansion it proposed that the Au Hydride formation occurs synergistally with the formation of a cerium oxyhydride. The temperature reversible nature, whilst remaining in a reducing atmosphere, demonstrates the activation of hydrogen without consumption of oxygen from the supporting ceria lattice.

18.
J Pharmacol Exp Ther ; 374(1): 211-222, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32345620

RESUMEN

The clinical use of first-generation phosphoinositide 3-kinase (PI3K)δ inhibitors in B-cell malignancies is hampered by hepatotoxicity, requiring dose reduction, treatment interruption, and/or discontinuation of therapy. In addition, potential molecular mechanisms by which resistance to this class of drugs occurs have not been investigated. Parsaclisib (INCB050465) is a potent and selective next-generation PI3Kδ inhibitor that differs in structure from first-generation PI3Kδ inhibitors and has shown encouraging anti-B-cell tumor activity and reduced hepatotoxicity in phase 1/2 clinical studies. Here, we present preclinical data demonstrating parsaclisib as a potent inhibitor of PI3Kδ with over 1000-fold selectivity against other class 1 PI3K isozymes. Parsaclisib directly blocks PI3K signaling-mediated cell proliferation in B-cell lines in vitro and in vivo and indirectly controls tumor growth by lessening immunosuppression through regulatory T-cell inhibition in a syngeneic lymphoma model. Diffuse large B-cell lymphoma cell lines overexpressing MYC were insensitive to proliferation blockade via PI3Kδ signaling inhibition by parsaclisib, but their proliferative activities were reduced by suppression of MYC gene transcription. Molecular structure analysis of the first- and next-generation PI3Kδ inhibitors combined with clinical observation suggests that hepatotoxicity seen with the first-generation inhibitors could result from a structure-related off-target effect. Parsaclisib is currently being evaluated in multiple phase 2 clinical trials as a therapy against various hematologic malignancies of B-cell origin (NCT03126019, NCT02998476, NCT03235544, NCT03144674, and NCT02018861). SIGNIFICANCE STATEMENT: The preclinical properties described here provide the mechanism of action and support clinical investigations of parsaclisib as a therapy for B-cell malignancies. MYC overexpression was identified as a resistance mechanism to parsaclisib in DLBCL cells, which may be useful in guiding further translational studies for the selection of patients with DLBCL who might benefit from PI3Kδ inhibitor treatment in future trials. Hepatotoxicity associated with first-generation PI3Kδ inhibitors may be an off-target effect of that class of compounds.


Asunto(s)
Hígado/efectos de los fármacos , Linfoma/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3/efectos adversos , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Pirazoles/efectos adversos , Pirazoles/farmacología , Pirimidinas/efectos adversos , Pirimidinas/farmacología , Pirrolidinas/efectos adversos , Pirrolidinas/farmacología , Animales , Antineoplásicos/efectos adversos , Antineoplásicos/farmacología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Femenino , Humanos , Factores Inmunológicos/efectos adversos , Factores Inmunológicos/farmacología , Ratones , Ensayos Antitumor por Modelo de Xenoinjerto
19.
G3 (Bethesda) ; 10(5): 1585-1597, 2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32265286

RESUMEN

N-Glycanase 1 (NGLY1) deficiency is an ultra-rare, complex and devastating neuromuscular disease. Patients display multi-organ symptoms including developmental delays, movement disorders, seizures, constipation and lack of tear production. NGLY1 is a deglycosylating protein involved in the degradation of misfolded proteins retrotranslocated from the endoplasmic reticulum (ER). NGLY1-deficient cells have been reported to exhibit decreased deglycosylation activity and an increased sensitivity to proteasome inhibitors. We show that the loss of NGLY1 causes substantial changes in the RNA and protein landscape of K562 cells and results in downregulation of proteasomal subunits, consistent with its processing of the transcription factor NFE2L1. We employed the CMap database to predict compounds that can modulate NGLY1 activity. Utilizing our robust K562 screening system, we demonstrate that the compound NVP-BEZ235 (Dactosilib) promotes degradation of NGLY1-dependent substrates, concurrent with increased autophagic flux, suggesting that stimulating autophagy may assist in clearing aberrant substrates during NGLY1 deficiency.


Asunto(s)
Retículo Endoplásmico , Regulación de la Expresión Génica , Retículo Endoplásmico/metabolismo , Humanos , Células K562 , Péptido-N4-(N-acetil-beta-glucosaminil) Asparagina Amidasa/genética , Complejo de la Endopetidasa Proteasomal/metabolismo
20.
PLoS One ; 15(4): e0231877, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32315352

RESUMEN

Alterations in fibroblast growth factor receptor (FGFR) genes have been identified as potential driver oncogenes. Pharmacological targeting of FGFRs may therefore provide therapeutic benefit to selected cancer patients, and proof-of-concept has been established in early clinical trials of FGFR inhibitors. Here, we present the molecular structure and preclinical characterization of INCB054828 (pemigatinib), a novel, selective inhibitor of FGFR 1, 2, and 3, currently in phase 2 clinical trials. INCB054828 pharmacokinetics and pharmacodynamics were investigated using cell lines and tumor models, and the antitumor effect of oral INCB054828 was investigated using xenograft tumor models with genetic alterations in FGFR1, 2, or 3. Enzymatic assays with recombinant human FGFR kinases showed potent inhibition of FGFR1, 2, and 3 by INCB054828 (half maximal inhibitory concentration [IC50] 0.4, 0.5, and 1.0 nM, respectively) with weaker activity against FGFR4 (IC50 30 nM). INCB054828 selectively inhibited growth of tumor cell lines with activation of FGFR signaling compared with cell lines lacking FGFR aberrations. The preclinical pharmacokinetic profile suggests target inhibition is achievable by INCB054828 in vivo with low oral doses. INCB054828 suppressed the growth of xenografted tumor models with FGFR1, 2, or 3 alterations as monotherapy, and the combination of INCB054828 with cisplatin provided significant benefit over either single agent, with an acceptable tolerability. The preclinical data presented for INCB054828, together with preliminary clinical observations, support continued investigation in patients with FGFR alterations, such as fusions and activating mutations.


Asunto(s)
Morfolinas/uso terapéutico , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirimidinas/uso terapéutico , Pirroles/uso terapéutico , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Administración Oral , Animales , Línea Celular Tumoral , Femenino , Semivida , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Ratones SCID , Morfolinas/química , Morfolinas/farmacocinética , Neoplasias/patología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacocinética , Pirimidinas/química , Pirimidinas/farmacocinética , Pirroles/química , Pirroles/farmacocinética , Ratas , Ratas Desnudas , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/metabolismo , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
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