How many seniors have had metal knee or hip transplants? Personally I suffered a torn meniscus a few years ago and was diagnosed with osteo arthritis at the same time. I searched dilligently for an osteo that would take my insurance, and the guy I found wanted to do a knee transplant. Fortunately, my GP said try PT first.
So this is one more variable that can really screw up an Alzheimer's trial:
Excerpt:
Introduction Metals are a component of the earth’s crust and exist in the water, air, and a variety of ecosystems. They can generally be divided into two groups: essential and non-essential metals. Essential metals include chromium, cobalt, copper (Cu), iron (Fe), lithium, magnesium, manganese (Mn), nickel, selenium, and zinc (Zn). These trace metals usually act as a cofactor of enzymes to regulate cellular activities. For example, Mn is required for the activity of arginase, hydrolases, lyases, glutamine synthetase, and superoxide dismutase (SOD) 1. Thus, these metals are involved in a whole host of physiological processes, such as electron transport, oxygen transportation, protein modification, neurotransmitter synthesis 2, 3, redox reactions, immune responses, cell adhesion, and protein and carbohydrate metabolism 1, to name a few. Metals accumulate in the brain, indicating their important roles in the nervous system. Deficiency of these metals has been associated with various neurological diseases. For example, Fe deficiency is related to restless leg syndrome, pediatric stroke, breath-holding spells, pseudotumor cerebri, and cranial nerve palsy 4, 5.
Although metals are important for animals and plants, they usually are required in trace amounts. Excessive metal levels accumulate in various organs, including the brain. Elevated levels of metals may induce various detrimental intracellular events, including oxidative stress, mitochondrial dysfunction, DNA fragmentation, protein misfolding, endoplasmic reticulum (ER) stress, autophagy dysregulation, and activation of apoptosis 6– 13. These effects may alter neurotransmission and lead to neurodegeneration, which can manifest as cognitive problems, movement disorders, and learning and memory dysfunction. To date, metal-induced neurotoxicity has been associated with multiple neurological diseases in humans, including Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), autism spectrum disorders (ASDs), Guillain–Barré disease (GBD), Gulf War syndrome (GWS), Huntington’s disease (HD), manganism, multiple sclerosis, Parkinson’s disease (PD), and Wilson’s disease (WD) 3, 14– 18. Here, we address the neurotoxicity of several metals as well as the human neurological diseases associated with these metals.
