Health and Medicine (Audio)

Organs renew and repair themselves through stem cell systems that respond to injury, microbes, and local signals. Ophir Klein, M.D., Ph.D., of Cedars-Sinai Medical Center explains how the intestine shifts into regenerative states after injury, how long-term changes in the stem cell niche may shape later responses, and how different regions of the colon take on distinct identities. Klein also examines how bacteria help control regional gene expression in the colon, why the lining of the mouth heals faster than skin, and how oral wound healing depends on signaling between epithelial and mesenchymal cells. The program also looks at bioengineering approaches designed to control developmental signals more precisely. Together, these examples show how tissues adapt, heal, and organize themselves, pointing toward better ways to understand regeneration and improve tissue repair. Series: "Stem Cell Channel" [Health and Medicine] [Science] [Show ID: 40849]

Bias in health AI can shape who gets care, how fairly risk is measured, and whether automation helps or harms patients. Karandeep Singh, M.D., M.M.S.C. explains that predictive AI can reflect historical, representation, measurement, learning, evaluation, and deployment bias, especially when models are trained on limited populations or use flawed proxies for illness and access to care. Singh also describes generative AI as a system trained first to predict text and then to follow instructions, with bias entering through training data, instruction tuning, prompts, and outside information sources. Alongside these risks, he highlights practical uses such as AI-assisted sepsis quality review and patient outreach workflows, while emphasizing governance, human oversight, disclosure, and careful measurement of whether these tools actually improve care. Series: "Exploring Ethics" [Health and Medicine] [Humanities] [Science] [Show ID: 41365]

AI in healthcare raises urgent questions about bias, privacy, and power. Safiya U. Noble, Ph.D., examines how AI systems can reproduce social and racial inequities when they rely on incomplete data, hidden assumptions, and proxies such as healthcare spending. Noble points to problems in search engines, image generation, facial recognition, and medical algorithms, including cases where systems mislabel darker skin, fail more often on Black women, or favor white patients over sicker Black patients. She also highlights the risks of turning sensitive public and patient data over to large technology companies. Rather than treating AI as a neutral solution, Noble emphasizes the need for human judgment, community participation, stronger data protections, and smaller expert models with local control so healthcare decisions better reflect people’s real lives and social context. Series: "Exploring Ethics" [Health and Medicine] [Humanities] [Science] [Show ID: 41364]

Alzheimer’s disease unfolds over many years through a complex interplay of amyloid, tau, genetics, lipid biology, and the brain’s immune response. John Hardy, Ph.D., explains how rare inherited forms of Alzheimer’s disease helped shape current thinking about how the disease begins, then connects those discoveries to broader questions about late onset disease and why it develops differently across people. Hardy shows that amyloid and tau are linked but not identical, and argues that problems with protein buildup and clearance both matter in understanding the disease. He also emphasizes that Alzheimer’s is not a single event but a long process, which makes prediction, diagnosis, and treatment especially difficult. While current amyloid-targeting therapies can help and show measurable benefit, Hardy says they do not stop the disease, underscoring the need for earlier diagnosis, better treatments, and wider access to care Series: "Shiley Endowed Lecture" [Health and Medicine] [Show ID: 41250]

Seizures caused by epilepsy can have a dramatic impact on one's quality of life. For Nolan, his seizures cost him everyday independence, including the ability to drive. When he decided to have surgery, he chose awake brain surgery led by Dr. Edward Chang, a neurosurgeon at UCSF. During surgery, Nolan speaks and responds as the medical team carefully maps the language regions of his brain — guiding their treatment of him while protecting his ability to communicate. The result opens a path back toward the freedoms Nolan has been missing. [Health and Medicine] [Show ID: 41414]