No abstract

It has been possible to demonstrate and characterize high phospholipase activities in mycelia of Rhizopus arrhizus and Mucor javanicus by use of a system in which substrates were dissolved in diisopropyl ether. Such activities were associated with bound enzymes and would have been difficult to detect using aqueous assay systems. In both cases, phosphatidylcholine hydrolysis was by phospholipase A1 (EC 3.1.1.32) activity followed by the action of lysophospholipase (EC 3.1.1.5). Phospholipase D (EC 3.1.4.4) activity was also detected. The methods used appear to be of general applicability for the detection and study of insoluble phospholipases.

Chimeric Antigen Receptor (CAR) T cell therapy has recently begun to be used for solid tumors such as glioblastoma multiforme. Many children with pediatric malignant brain tumors develop extensive long-term morbidity of intensive multimodal curative treatment. Others with certain diagnoses and relapsed disease continue to have limited therapies and a dismal prognosis. Novel treatments such as CAR T cells could potentially improve outcomes and ameliorate the toxicity of current treatment. In this review, we discuss the potential of using CAR therapy for pediatric brain tumors. The emerging insights on the molecular subtypes and tumor microenvironment of these tumors provide avenues to devise strategies for CAR T cell therapy. Unique characteristics of these brain tumors, such as location and associated morbid treatment induced neuro-inflammation, are novel challenges not commonly encountered in adult brain tumors. Despite these considerations, CAR T cell therapy has the potential to be integrated into treatment schema for aggressive pediatric malignant brain tumors in the future.

When the electric organ (EO) of weakly electric fish is amputated, a blastema forms from which new EO and muscle cells arise. However, the progenitor cells that contribute to the blastema are unknown. We studied regeneration of the electric organ in Sternopygus to answer this question. The EO of this species is composed of electrocyte cells surrounded by peripheral bundles of muscle fibers. Fish were injected with 5'-bromodeoxyuridine (BrdU) 24 h after amputating the terminal portion of the EO. At this time, a population of small cells were labeled in the extracellular matrix between electrocytes and muscle fibers. These cells did not label in control fish injected with saline or in nonamputated BrdU-injected fish. For the first 6 days postamputation, increasing numbers of BrdU-labeled cells appeared at the wound margin. A blastema formed 6 days after amputation and contained numerous BrdU-labeled cells. At 10 days postamputation, clusters of BrdU-positive cells were seen throughout the wound margin and proximal blastema. At 14 days, BrdU-labeled nuclei were present within developing electrocytes. Labeling alternate sections with MF20 antimyosin and AE1 anticytokeratin antibodies confirmed that BrdU-positive multinucleate cells coexpress myosin and cytokeratin epitopes, diagnostic of newly regenerated electrocytes. Electron micrographs reveal that the small cells surrounding muscles and electrocytes are similar; they contain an elongate nucleus, are largely devoid of cytoplasm, and possess few organelles. This morphology and evidence of myogenic potential suggests that these cells are satellite cells.

We developed a novel conceptualization of one component of creativity in narratives by integrating creativity theory and distributional semantics theory. We termed the new construct divergent semantic integration (DSI), defined as the extent to which a narrative connects divergent ideas. Across nine studies, 27 different narrative prompts, and over 3500 short narratives, we compared six models of DSI that varied in their computational architecture. The best-performing model employed Bidirectional Encoder Representations from Transformers (BERT), which generates context-dependent numerical representations of words (i.e., embeddings). BERT DSI scores demonstrated impressive predictive power, explaining up to 72% of the variance in human creativity ratings, even approaching human inter-rater reliability for some tasks. BERT DSI scores showed equivalently high predictive power for expert and nonexpert human ratings of creativity in narratives. Critically, DSI scores generalized across ethnicity and English language proficiency, including individuals identifying as Hispanic and L2 English speakers. The integration of creativity and distributional semantics theory has substantial potential to generate novel hypotheses about creativity and novel operationalizations of its underlying processes and components. To facilitate new discoveries across diverse disciplines, we provide a tutorial with code (osf.io/ath2s) on how to compute DSI and a web app (osf.io/ath2s) to freely retrieve DSI scores.