Category: life extension – Page 467
Episode two of this series explores the dawn of the era of a science-based search for truth, in particular, the study of life and the microscopic cells that form our bodies
Click on photo to start video.
With that basic research, mankind found the first major clue to the origins of aging and death. They discovered that some cells in our bodies that may never die. These “immortal cells” and the philosophical shift in thinking they engendered, will likely change medicine as we know it.
Neutral evolution shapes lifespan and aging
Different African killifish species vary extensively in their lifespans—from just a few months to several years. Scientists from the Max Planck Institute for Biology of Ageing in Cologne investigated how different lifespans have evolved in nature and discovered a fundamental mechanism by which detrimental mutations accumulate in the genome causing fish to age fast and become short-lived. In humans, mutations accumulate mainly in the genes that are active in old age.
An Interview with Sergey Young
My colleague Nicola Bagalà recently had the opportunity to interview Sergey Young, a board member of XPRIZE and the creator of the $100m Longevity Vision Fund. As you probably know, at the end of May this year XPrize hosted a 2-day workshop to better understand the bottlenecks and opportunities of the longevity industry, and in this interview, Sergey is sharing his vision on what can — and should — be done to accelerate the development of new therapies addressing aging.
We recently had the opportunity to interview Sergey Young, a board member of XPRIZE and the creator of the $100m Longevity Vision Fund.
When did you first become interested in healthy life extension, and why?
My interest began with a routine visit to a doctor. Five years ago, at the age of 42, my blood tests – which I neglected for 7 years, thinking I was in perfect health – showed that my cholesterol was extremely high, putting me at risk of one of the most common killers: heart disease.
Aubrey DeGrey, Michael Rae on SENS Research update with Bill Faloon
And Life Extension. Produced for broadcast on ABC TV-25 in Palm Beach and other stations…
The Circle of Willes in Cryonics Perfusion
Blood flows into the brain primarily via the carotid arteries and the vertebral arteries. The Circle of Willis is a circular arterial structure in the brain that connects blood flowing in from the carotid arteries with blood flowing in from the basilar artery (which is fed by the vertebral arteries). Blood flows from the Circle of Willis into brain tissue via the anterior, middle, and posterior cerebral arteries. Many studies have shown that the Circle of Willis is incomplete in most people. A 1998 study of 150 healthy adult volunteers showed a complete Circle of Willis in only 42% of cases — more often complete in younger persons and females [RADIOLOGY; Krabbe-Hartkamp, MJ; 207:103–111 (1998)]. A slightly more encouraging 2002 study of 118 healthy volunteers in the 65–68 age group, showed 47% had a complete Circle of Willis [THE JOURNAL OF CARDIOVASCULAR SURGERY; Macchi, C; 43:887–890 (2002)]
For cryonics purposes, it has been believed that perfusion into the carotid arteries, but not into the vertebral arteries will result in incomplete perfusion of the brain if the Circle of Willis is not complete. In particular, if both posterior communicating arteries are missing, then perfusing only through the carotid arteries will result in no blood getting to parts of the brain supplied by the posterior cerebral arteries. Both posterior communicating arteries were missing in 11% of those in the 1998 study and in 14% of those in the 2002 study cited above.
Nonetheless, a 2008 study showing Circle of Willis complete in only 40% of 99 patients found no case of insufficient perfusion in functional tests of patients given unilateral cerebral perfusion. The authors concluded that “extracranial collateral circulation” provides an alternative pathway to the Circle of Willis for cerebral crossperfusion [EUROPEAN JOURNAL OF CARDIOTHORACIC SURGERY; Urbanski, PP; 33:402–408 (2008)]. Although persons with missing posterior communicating arteries could easily have pathways to opposite sides of the brain, other variants of Circle of Willis incompleteness would be expected to prevent perfusion across hemispheres.
A Step Closer to Regenerating the Aging Thymus
Researchers from the Monash Biomedicine Discovery Institute have made progress in the quest to rejuvenate the aging immune system by identifying the factors responsible for the age-related decline of the thymus.
The thymus shrinks as we age
The thymus is one of the most important organs in the body, and it is where thymocytes produced in the bone marrow travel to become new T cells before being trained in the lymph nodes to become the defenders of the adaptive immune system. However, as we get older, the thymus increasingly turns to fat and starts to shrink, causing its ability to produce new T cells to fall dramatically. This process is known as thymic involution and actually begins shortly after puberty, so this is one aspect of aging that begins fairly early in life, although it is many decades later before its decline causes serious health issues.
