Medical-Lee Speaking

Few things feel more intuitive than our sense of right and wrong. How do agency, valence, and processing levels of moral stimuli influence this sense, and are the circuits involved lateralized in one or the other cerebral hemispheres? To address these questions, I used caloric vestibular stimulation (CVS) treatments followed by the Explicit Moral Judgment Test (EMJT) to probe the biological circuitry of moral judgments. Subjects’ moral evaluations were modulated by CVS treatments across agency, valence, and processing variables, providing evidence for the lateralization of newly identified moral modules concerned with positive-subtraction and self-positive processing. Continue reading »

In “Creation of a Bacterial Cell Controlled by a Chemically Synthesized Genome”, Venter et al. report the first successful design, synthesis, assembly, and transplantation of an artificial genome into a host cell. The bacterial host subsequently underwent phenotypic transformation, resulting in the first engineered species created from a synthetic genome. Continue reading »

The recent development of pluripotence induction in somatic cell lines raised the possibility of organ regeneration from a patient’s own cells. But until our lab’s research, it wasn’t known whether these induced pluripotent stem cells (iPSC) could fully restore vital organ function. We demonstrated that iPSC-derived differentiated hepatocytes possess the functional and proliferative capacities required for complete liver regeneration in a murine model of fumarylacetoacetate hydrolase (FAH) deficiency. However, because we transplanted fibroblast-derived iPSCs into strain-matched blastocysts, our model relied exclusively on iPSC differentiation in vivo during embryonic development, where exposure to developmental signaling may have contributed significantly to their functional capacities. Continue reading »

Transforming Growth Factor Beta (TGF-β) constitutes a superfamily of cytokines – a class of intercellular signaling molecules in some ways similar to hormones – deployed across the animal kingdom by most cell types to facilitate cellular communication. During the 1970s, in the midst of a broad attempt to identify proteins involved in tumorigenesis – what was at the time described as “transformation” and defined as in vitro anchorage-independent growth (1) – TGF-β was identified as one of two polypeptides, along with TGF-α, responsible for inducing rat kidney fibroblast culture growth in soft agar conditions (4). Continue reading »