Science Society

This episode presents a fascinating conversation with Dr. Orly Lazarov about her groundbreaking research on Alzheimer’s Disease (AD) and the pivotal role of hippocampal neurogenesis in memory deficits observed in this condition.

The recruitment of new, immature neurons into the memory "engram" or storage, which is essential for hippocampus-dependent tasks, is significantly deficient in familial Alzheimer’s Disease (FAD) cases. These recruited immature neurons exhibited compromised spine density and altered transcript profiles in FAD.

In a remarkable revelation, Dr. Lazarov’s team demonstrated that targeted enhancement of neurogenesis in FAD mice can restore the number of new neurons in the engram, along with the dendritic spine density and the transcription signature of both immature and mature neurons. This restoration leads to memory rescue. Additionally, the team found that chemogenetic inactivation of immature neurons reversed mouse performance and impaired memory.

Notably, AD-linked genes like App, ApoE, and Adam10 were among the top differentially expressed genes in the engram. Dr. Lazarov's study implies that defective neurogenesis contributes significantly to memory failure in Alzheimer's disease.

Join us as we delve into the complex world of neurogenesis, memory, and Alzheimer's disease with Dr. Lazarov.

Keywords: Alzheimer's Disease, Neurogenesis, Memory Failure, Hippocampus, Familial Alzheimer's Disease, Engram, Memory Rescue, Dendritic Spine Density.

Augmenting neurogenesis rescues memory impairments in Alzheimer’s disease by restoring the memory-storing neurons https://doi.org/10.1084/jem.20220391

In this episode, we have the pleasure of talking with Dr. Helena Florindo, an innovator in the field of cancer immunotherapy. Our conversation revolves around her recent work focused on identifying novel small molecules that can modulate the programmed cell death protein 1 (PD-1)/PD-ligand 1 (PD-L1) interaction, which has shown exciting clinical outcomes in diverse human cancers.

While monoclonal antibodies are currently the only approved inhibitors of PD-1/PD-L1, the majority of patients do not respond to these immune checkpoint inhibitors, highlighting the importance of developing new immunotherapeutic agents.

In a transdisciplinary approach combining in silico analyses with in vitro, ex vivo, and in vivo experimental studies, Dr. Florindo's team has discovered small molecules that stimulate human adaptive immune responses. Unlike currently available biological compounds, these novel small molecules have shown the ability to enhance the infiltration of T lymphocytes into three-dimensional solid tumor models and recruit cytotoxic T lymphocytes to the tumor microenvironment in vivo.

Join us as Dr. Florindo discusses the promising potential of these small molecules to transform cancer immunotherapy by regulating the PD-L1/PD-1 signaling pathway and promoting an extensive infiltration of effector CD8 T cells to the tumor microenvironment.

Keywords: Cancer Immunotherapy, Small Molecules, PD-1, PD-L1, Immune Checkpoint Inhibitors, T Lymphocytes, Dr. Helena Florindo.

Therapeutic targeting of PD-1/PD-L1 blockade by novel small-molecule inhibitors recruits cytotoxic T cells into solid tumor microenvironment https://jitc.bmj.com/content/10/7/e004695

Join us for an exciting discussion with Valtteri Wikström, who delves into the intriguing world of inter-brain synchronization during online gameplay. By using EEG hyperscanning, Wikström and his team investigated cooperative performance during real-time online two-player gameplay, where participants were physically isolated and communicated solely through on-screen actions.

The results of the study showed a correlation between momentary performance and gamma synchronization, and average performance with alpha synchronization. Interestingly, synchronization across frequency bands decreased during a playing session, but it was elevated in the second of two sessions. This provides an interesting look into how online real-time joint coordination occurs without any physical co-presence or video and audio connection and how changes in inter-brain EEG phase synchrony can be observed continuously during the interaction.

In this episode, we discuss these findings in-depth, and explore what this could mean for the future of online multiplayer gaming and potentially, other forms of remote collaboration and communication.

Keywords: EEG hyperscanning, Inter-brain synchronization, Online gameplay, Cooperative performance, Valtteri Wikström.

Inter-brain synchronization occurs without physical co-presence during cooperative online gaming https://doi.org/10.1016/j.neuropsychologia.2022.108316

Join us for a fascinating conversation with Nik Kornder, MSc, as he enlightens us on the rather surprising self-cleaning mechanisms of the Caribbean tube sponge, Aplysina archeri. Contrary to common assumptions, these sponges actively move particle-trapping mucus against the direction of their internal water flow. This mucus-embedded waste is then expelled into the surrounding water through periodic surface contractions, colloquially known as "sneezing."

Kornder and his team used time-lapse video footage and meticulous analyses to uncover this intriguing phenomenon. Interestingly, this expulsion of waste results in a significant flux of detritus, which is actively consumed by sponge-associated fauna. Not only does this provide a fresh perspective on how these sponges prevent their filter system from clogging, but it also hints at the ecological significance of these "sneezes" on the nutrient cycling of Caribbean coral reefs.

Join us as we delve into this intriguing marine mystery and discuss the potential parallels of these sneezing mechanisms with other animals, including humans.

Keywords: Nik Kornder, Sponge Sneezing, Aplysina archeri, Self-cleaning mechanism, Mucus transport, Marine ecology, Caribbean coral reefs.

Sponges sneeze mucus to shed particulate waste from their seawater inlet pores https://doi.org/10.1016/j.cub.2022.07.017 Department of Freshwater and Marine Ecology, University of Amsterdam

Step into the intriguing realm of quantum technology with Dr. Serrano as he sheds light on the phenomenal properties of rare-earth ions (REIs). These solid-state systems hold great promise in building light–matter interfaces at the quantum level, thanks to their capacity for narrow optical and spin homogeneous linewidths, resulting in long-lived quantum states.

In our conversation, Dr. Serrano explores the potential applications of REIs in photonic quantum technologies such as memories for light, optical–microwave transduction, and computing. Despite the exciting possibilities, progress has been hampered by the lack of materials with environments quiet enough to fully exploit the properties of REIs.

Enter europium molecular crystals. These molecular systems, as Dr. Serrano discusses, exhibit linewidths orders of magnitude narrower than other molecular systems, making them an efficient solution for optical spin initialization, coherent storage of light, and optical control of ion–ion interactions.

Tune in to discover how these findings set the stage for rare-earth molecular crystals to become a new platform for photonic quantum technologies, bridging the gap between highly coherent emitters and the unmatched versatility of molecular materials.

Keywords: Dr. Serrano, Rare-Earth Ions, Quantum Technology, Photonic Quantum Technologies, Europium Molecular Crystals, Coherent Emitters, Molecular Materials.

Serrano, D., Kuppusamy, S.K., Heinrich, B. et al. Ultra-narrow optical linewidths in rare-earth molecular crystals. Nature 603, 241–246 (2022). https://doi.org/10.1038/s41586-021-04316-2

Imagine a world where artificial neurons not only rival their biological counterparts in function but also exceed them in speed and scale. Dr. Onen takes us on a captivating journey through this very realm in our latest episode.

Biological neurons and synapses, though remarkably efficient, are constrained by the speed of information processing in the aqueous medium through which action potentials propagate. But what if we could transcend these limitations? Enter nanoscale protonic programmable resistors, artificial solid-state neurons that are not subject to the same time and voltage constraints as their biological analogs.

Dr. Onen delves into his groundbreaking work, where he and his team prototyped these resistors, crafting them to be 1000 times smaller than biological neurons and utilizing complementary metal-oxide semiconductor–compatible materials. These devices can withstand high electric fields and display energy-efficient modulation characteristics at room temperature, operating 10,000 times faster than biological synapses.

In this conversation, Dr. Onen elaborates on how these nanoscale devices pave the way for accelerated deep learning applications. Tune in to explore how these advancements can revolutionize artificial neural networks, offering a promising direction for implementing applications that can benefit from rapid ionic motion.

Keywords: Dr. Onen, Protonic Programmable Resistors, Nanoscale, Deep Learning, Artificial Neurons, Biological Neurons, Synapses, Solid-State Devices, Ionic Transport, Complementary Metal-Oxide Semiconductor.

Nanosecond protonic programmable resistors for analog deep learning https://doi.org/10.1126/science.abp8064

In this fascinating episode, Dr. Harrington unpacks his cutting-edge research exploring the potential of mistletoe viscin, a natural cellulosic adhesive, for various material and biomedical applications.

Viscin, which consists of cellulose microfibrils encapsulated by a humidity-responsive matrix, possesses an array of properties that render it a promising candidate for diverse applications. Remarkably, its humidity-activated self-adhesive capabilities allow for mechanical drawing into stiff and sticky fibers, which can then be 'welded' into complex 2D and 3D architectures under ambient conditions.

Dr. Harrington's team also found that viscin can be processed into stiff, transparent free-standing films through biaxial stretching in the hydrated state, followed by drying. This process results in cellulose microfibrils aligning along local stress fields. Additionally, viscin exhibits robust adhesion to a variety of materials, including metals, plastics, glass, and even biological tissues like skin and cartilage.

Notably, the strong adherence of viscin to skin presents a compelling case for its use as a wound sealant, as Dr. Harrington further demonstrates. By leveraging the properties of this hygro- and mechano-responsive fiber-reinforced adhesive, researchers can unlock transformative potential for bioinspired and biomedical applications.

Keywords: Dr. Harrington, Mistletoe Viscin, Cellulosic Adhesive, Bioinspired Design, Biomedical Applications, Humidity-Activated Self-Adhesive, Wound Sealant, Material Applications.

Nils Horbelt, Peter Fratzl, Matthew J Harrington, Mistletoe viscin: a hygro- and mechano-responsive cellulose-based adhesive for diverse material applications https://doi.org/10.1093/pnasnexus/pgac026

Dr. Demirci joins us in this captivating episode to explore the use of pulsed light as an alternative antimicrobial intervention in the food industry.

The first part of his study was dedicated to defining the spectrum and energy characteristics of pulsed light. Following this, Dr. Demirci delved into investigating the germicidal response of a range of microorganisms, including Escherichia coli, Salmonella enterica subsp. enterica ser. Typhimurium, Listeria monocytogenes, Bacillus cereus (vegetative cells and endospores), Aspergillus niger spores, and Penicillium roqueforti spores to pulsed light treatments.

The organisms were treated using three different broad-spectrum xenon gas flashlamps and were subjected to up to 15 pulses. Each microorganism displayed a significant interaction of flashlamp type and treatment duration.

Further, Dr. Demirci treated E. coli with pulsed light using a type B flashlamp and light filters to selectively deliver visible, near-infrared, and combined visible-near-infrared radiation to the cells. Transmission Electron Microscopy (TEM) images were also obtained to observe physical effects on the cellular structures.

The findings of this study indicate that microbial sensitivity to pulsed light treatment varies across species and is predominantly attributed to the ultraviolet portion of the spectrum. Join us as we delve into these results and discuss the potential of this technology for the food industry.

Keywords: Dr. Demirci, Pulsed Light, Antimicrobial Intervention, Food Industry, Escherichia coli, Salmonella enterica, Listeria monocytogenes, Bacillus cereus, Aspergillus niger, Penicillium roqueforti, Xenon Gas Flashlamps, Transmission Electron Microscopy, Microbial Sensitivity, Ultraviolet Radiation.

Characterization of pulsed light for microbial inactivation https://doi.org/10.1016/j.jfoodeng.2022.111152 Pulsed light treatment susceptibility differs for Gram -, Gram +, and spores/fungi.

In this groundbreaking episode, Dr. Tarazi reveals exciting insights into the world of synthetic embryos constructed from embryonic stem cells (ESCs) in an ex-utero setup. This pioneering study provides an intriguing look into the future of developmental biology and biomedical research.

Dr. Tarazi's team demonstrated that naive ESCs could independently give rise to entire gastrulating embryo-like structures complete with embryonic and extraembryonic compartments. This significant feat was accomplished by adapting a recently established platform for the prolonged ex-utero growth of natural embryos.

The experiment involved co-aggregating non-transduced ESCs with naive ESCs transiently expressing Cdx2 or Gata4, crucial for promoting priming toward trophectoderm and primitive endoderm lineages, respectively. The result was the creation of post-gastrulation synthetic whole embryo models (sEmbryos).

These sEmbryos accomplished gastrulation and advanced through key developmental milestones, developing organ progenitors within complex extraembryonic compartments akin to E8.5 stage mouse embryos. This illuminating study underscores the remarkable potential of naive pluripotent cells to self-organize and functionally reconstitute and model the entire mammalian embryo beyond gastrulation.

Join us as we delve into this fascinating world of synthetic embryos with Dr. Tarazi.

Keywords: Dr. Tarazi, Synthetic Embryos, Embryonic Stem Cells, Ex Utero, Gastrulation, Embryo-like Structures, Naive ESCs, Cdx2, Gata4, Trophectoderm, Primitive Endoderm, Developmental Milestones, Biomedical Research.

Post-Gastrulation Synthetic Embryos Generated Ex Utero from Mouse Naïve ESCs by Shadi Tarazi et al. https://doi.org/10.1016/j.cell.2022.07.028 Weizmann Institute of Science

This episode features a conversation with renowned scientist Dr. Levin who shares exciting updates from his lab’s groundbreaking work. Focusing on understanding and controlling complex pattern formation, Dr. Levin’s team explores the fascinating crossroads of molecular genetics, biophysics, and computational modeling.

The Levin lab operates at the forefront of scientific exploration, working with organisms such as frogs, flatworms, zebrafish, and even human tissues in culture. Their projects traverse a wide range of topics including regeneration, embryogenesis, cancer, and learning plasticity – all seen as instances of how cellular networks process information.

Dr. Levin's aim extends beyond just deciphering the necessary molecular mechanisms for morphogenesis. He is on a quest to unravel and harness the cooperative signaling dynamics that enable complex bodies to build and remodel themselves toward a correct structure in spite of unpredictable environmental disruptions.

This episode offers a deep dive into the quest to understand how individual cell behaviors are orchestrated toward appropriate large-scale outcomes, providing listeners with a glimpse into the future of biophysics and molecular genetics.

Keywords: Dr. Levin, Bioelectricity, Basal Cognition, Molecular Genetics, Biophysics, Computational Modeling, Pattern Formation, Regeneration, Embryogenesis, Cancer, Learning Plasticity, Cellular Networks, Morphogenesis.