RESUMEN
The High Beta Tokamak-Extended Pulse has recently incorporated a tangential multi-energy extreme ultraviolet and soft x-ray diagnostic system. This system enables measurements of the electron temperature and the examination of mode dynamics within the tokamak. While other systems have been built for poloidal views over similar temperature ranges, this is the first multi-energy tangential-view system designed to work in a temperature range below 200 eV in a tokamak. To facilitate these measurements, a filter wheel comprising five distinct groups of dual-filters has been developed and implemented. By employing a combination of 0.1 µm aluminum and 0.2 µm titanium filters, the system allows estimation of electron temperature profiles through reconstruction of the emission profile using the standard "double-foil" technique. The influence of impurities and filter oxide layers on measurement outcomes is examined. Results reveal that, while the absolute electron temperature values may exhibit some deviations, key characteristics like the electron temperature profile shape and inversion radius during sawtooth events remain consistent. This consistency confirms the system's suitability for core plasma studies. This system has proven effective in detecting and analyzing internal magnetohydrodynamic phenomena, such as sawteeth.
RESUMEN
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder caused by progressive loss of motor neurons and there is currently no effective therapy. Cytoplasmic mislocalization and aggregation of TAR DNA-binding protein 43 kDa (TDP-43) within the CNS is a pathological hallmark in sporadic ALS and prion-like propagation of pathogenic TDP-43 is thought to be implicated in disease progression. However, cell-to-cell transmission of pathogenic TDP-43 in the human CNS has not been confirmed experimentally. Here we used induced pluripotent stem cells (iPSCs)-derived cerebral organoids as recipient CNS tissue model that are anatomically relevant human brain. We injected postmortem spinal cord protein extracts individually from three non-ALS or five sporadic ALS patients containing pathogenic TDP-43 into the cerebral organoids to validate the templated propagation and spreading of TDP-43 pathology in human CNS tissue. We first demonstrated that the administration of spinal cord extracts from an ALS patient induced the formation of TDP-43 pathology that progressively spread in a time-dependent manner in cerebral organoids, suggesting that pathogenic TDP-43 from ALS functioned as seeds and propagated cell-to-cell to form de novo TDP-43 pathology. We also reported that the administration of ALS patient-derived protein extracts caused astrocyte proliferation to form astrogliosis in cerebral organoids, reproducing the pathological feature seen in ALS. Moreover, we showed pathogenic TDP-43 induced cellular apoptosis and that TDP-43 pathology correlated with genomic damage due to DNA double-strand breaks. Thus, our results provide evidence that patient-derived pathogenic TDP-43 can mimic the prion-like propagation of TDP-43 pathology in human CNS tissue. Our findings indicate that our assays with human cerebral organoids that replicate ALS pathophysiology have a promising strategy for creating readouts that could be used in future drug discovery efforts against ALS.
Asunto(s)
Esclerosis Amiotrófica Lateral , Priones , Humanos , Esclerosis Amiotrófica Lateral/patología , Médula Espinal/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Priones/metabolismo , Organoides/metabolismoRESUMEN
Three new diterpenoids (1-3) (two abietane type diterpenoids and a paralianone type diterpenoid), together with four known compounds (4-7) were isolated from the whole plants of Euphorbia peplus. Their structures were elucidated through spectroscopic analysis and physicochemical characteristics. The cytotoxic activities of compounds 1-7 against five human tumour cell lines were evaluated, however, they were inactive at the concentration of 40 µM. The compound 3 enhanced lysosomal biogenesis with Lyso Tracker staining intensity of 132.6%.
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Antineoplásicos Fitogénicos , Diterpenos , Euphorbia , Abietanos , Antineoplásicos Fitogénicos/farmacología , Diterpenos/farmacología , Humanos , Estructura MolecularRESUMEN
Traumatic joint injuries can result in significant cartilage defects, which can greatly increase the risk of osteoarthritis development. Due to the limited self-healing capacity of avascular cartilage, tissue engineering approaches are required for filling defects and promoting cartilage regeneration. Current approaches utilize invasive surgical procedures for extraction and implantation of autologous chondrocytes; therefore, injectable biomaterials have gained interest to minimize the risk of infection as well as patient pain and discomfort. In this study, we engineered biomimetic, hyaluronic acid (HA)-based cryogel scaffolds that possess shape-memory properties as they contract and regain their shape after syringe injection to noninvasively fill cartilage defects. The cryogels, fabricated with HA and glycidyl methacrylate at -20°C, resulted in an elastic, macroporous, and highly interconnected network that provided a conducive microenvironment for chondrocytes to remain viable and metabolically active after injection through a syringe needle. Chondrocytes seeded within cryogels and cultured for 15 days exhibited enhanced cell proliferation, metabolism, and production of cartilage extracellular matrix glycosaminoglycans compared with HA-based hydrogels. Furthermore, immunohistochemical staining revealed production of collagen type II from chondrocyte-seeded cryogels, indicating the maintenance of cell phenotype. These results demonstrate the potential of chondrocyte-seeded, HA-based, injectable cryogel scaffolds to promote regeneration of cartilage tissue for nonsurgically invasive defect repair. Impact statement Hyaluronic acid-based shape-memory cryogels provide a conducive microenvironment for chondrocyte adhesion, proliferation, and matrix biosynthesis for use in repair of cartilage defects. Due to their sponge-like elastic properties, cryogels can fully recover their original shape back after injection while not impacting metabolism or viability of encapsulated cells. Clinically, they provide an opportunity for filling focal cartilage defects by using a single, minimally invasive injection of a cell encapsulating biocompatible three-dimensional scaffold that can return to its original structure to fit the defect geometry and enable matrix regeneration.
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Cartílago Articular , Criogeles , Cartílago , Condrocitos , Humanos , Ácido Hialurónico/farmacología , Porosidad , Ingeniería de Tejidos , Andamios del TejidoRESUMEN
Five new diterpenoids, named euphorfischerins A-E, were isolated from the roots of Euphorbia fischeriana. Their chemical structures and absolute configurations were determined by interpretation of NMR, HR-ESI-MS, ECD and X-ray diffraction data. Euphorfischerin A showed cytotoxicity against the human cancer cell lines HeLa, H460 and Namalwa with IC50 values of 4.6, 11.5 and 16.4â µM, respectively, while euphorfischerin B gave comparable IC50 values of 9.5, 17.4 and 13.3â µM against the three cancer cell lines, respectively.
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Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Diterpenos/química , Diterpenos/farmacología , Euphorbia/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Modelos Moleculares , Neoplasias/tratamiento farmacológico , Raíces de Plantas/químicaRESUMEN
The first phytochemical investigation of the seeds of Euphorbia peplus led to the isolation and characterization of five new (1-5), named euphopepluanones A-E, and five known diterpenoids (6-10). Their structures were established by extensive spectroscopic analysis and X-ray crystallographic experiments. Euphopepluanones A-E (1-3) feature a very rare 5/11/5-tricyclic skeleton, and euphopepluanones D-E (4-5) represent the first report of lathyrane type diterpenoids found in E. peplus. The new compounds 1-5 were assessed for their activities to induce lysosomal biogenesis through LysoTracker Red staining, in which compounds 1 and 3 could significantly induce lysosomal biogenesis. In addition, compounds 1 and 3 could promote the nuclear translocation of TFEB, a master transcriptional factor of lysosomal genes, indicating that compounds 1 and 3 induced lysosomal biogenesis through activation of TFEB.
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Diterpenos/aislamiento & purificación , Euphorbia/clasificación , Lisosomas/efectos de los fármacos , Compuestos Macrocíclicos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Semillas/química , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Diterpenos/química , Diterpenos/metabolismo , Evaluación Preclínica de Medicamentos , Medicamentos Herbarios Chinos/química , Células HeLa , Humanos , Compuestos Macrocíclicos/metabolismo , Estructura Molecular , Biogénesis de Organelos , Extractos Vegetales/metabolismoRESUMEN
Clarifying changes in gastrointestinal tissue compressed by surgical stapler is a crucial prerequisite for stapler design optimization. For this study, a stapler was modified, and multifrequency bioimpedance of a porcine small intestine tissue compressed by the stapler was measured. The Cole Y model was fitted to the bioimpedance, and changes in tissue were analyzed using model parameters: G 0, extracellular fluid conductance; ΔG, intracellular fluid conductance; C cpeF, equivalent capacitance of cell membrane. The changes could be divided into two stages: first, all parameters decreased sharply with slopes more than 15.70 ± 2.67, 4.25 ± 1.23 µS/s and 72.68 ± 6.99 pF/s respectively; and subsequently, with an increase in compression strength, G 0 decreased with slopes less than 2.54 ± 0.40 µS/s, ΔG decreased slightly with slope of 0.26 ± 0.04 µS/s after fluctuating mildly, and C cpeF remained nearly invariant after initially increasing with slope of -2.94 ± 0.64 pF/s. In conclusion, when the stapler is closed, a portion of tissue is squeezed out of the measurement space, causing all parameters' sharp decrease. Subsequently, the stapler continues compressing the tissue, leading to extracellular fluid expulsion. The changes in intracellular fluid are related to the compression strength and may be explained by cell restoration. This study could provide a basis for stapler design optimization.