What is osteonecrosis? Osteonecrosis is a bone disease. It results from the loss of blood supply to the bone. Without blood, the bone tissue dies. This causes the bone to collapse. It may also cause the joints that surround the bone to collapse. If you have osteonecrosis, you may have pain or be limited in your physical activity. Osteonecrosis can develop in any bone, most often in the: Thigh bone (femur). Upper arm bone (humerus). Knees. Shoulders. Ankles. It is also called: Avascular necrosis. Aseptic necrosis. Ischemic necrosis.
What is vitiligo? Vitiligo is a chronic (long-lasting) disorder that causes areas of skin to lose color. When skin cells that make color are attacked and destroyed, the skin turns a milky-white color. No one knows what causes vitiligo, but it may be an autoimmune disease. In people with autoimmune diseases, the immune cells attack the body’s own healthy tissues by mistake, instead of viruses or bacteria. A person with vitiligo sometimes may have family members who also have the disease. There is no cure for vitiligo, but treatment may help skin tone appear more even.
Altering a key protein involved in the development of vitiligo may protect against—or even reverse—the pigmentation loss associated with the skin disorder in mice, according to recent research funded by the NIH’s National Institute of Arthritis and Musculoskeletal and Skin Diseases, and published in the journal Science Translational Medicine. Vitiligo is a progressive autoimmune disease in which the skin cells that impart color (melanocytes) are destroyed, resulting in white patches on the face, hands and other parts of the body. Scientists are unsure what causes vitiligo. They are investigating the biological mechanisms that trigger the disease, as well as its