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Red Gold - the epic story of blood Ask the Experts
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The Experts
Dr. Marc Kahn Dr. Marc Kahn, Associate Professor of Medicine, Tulane University School of Medicine
Dr. Paul J. Schmidt Dr. Paul J. Schmidt, Professor of Pathology, University of South Florida College of Medicine

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Q&A with the Experts
Q&A With the Experts

16. What are T-cells and where do they come from in the blood?

Answer: T-cells are a specific type of white cell that were thought to originally derive from the thymus, a gland in the chest, which is how they got their name. In fact, they do develop in the thymus, but are formed in the bone marrow. T-cells function along with other immune cells, called antigen-presenting cells, to allow for immune responses. These responses include activation of the immune system, recruitment of additional T-cells, and programmed cell death of infected or foreign cells.


17. I have B+ blood. Which would I have a more severe transfusion reaction to: A+ or B- blood?

Answer: You would nave no reaction to B- blood, but a potentially fatal reaction to A+ blood.


18. Can you get Creutzfeldt-Jakob Disease from a blood transfusion?

Answer: Epidemiologic studies have failed to demonstrate blood transmission of Creutzfeld-Jakob disease.


19. Concerning blood-borne diseases, what is so similar in our blood that monkeys' blood can carry diseases that could harm us?

Answer: It's not the blood that transmits the diseases, but the viruses that are carried in the blood, which can be transmitted between the species.


20. Is it true that blood is blue in the veins before it reaches the air?

Answer: Not really. Deoxygenated blood is less red than oxygenated blood. The color is a dark crimson.


21. Do you know of any current source of the purified blood clotting Factor XI?

Answer: Currently, Factor XI concentrates are licensed in Europe but not in the U.S. In the U.S., fresh frozen plasma is given to prevent bleeding in Factor XI-deficient patients.


22. My question concerns the blood-transmitted disease hepatitis C. How come the virus was not discovered at the time the HIV virus was isolated and identified? There seems to be less information as to the cause and behavior of this virus compared to HIV. Hepatitis C-infected individuals may not know they have this virus at all until symptoms occur, 10-20 years after the infection, with many people having absolutely no clue as to the moment and cause of this viral disease. How long can this virus live outside the body, and how is it transmitted from one person to another? Is it possible to get a virus like hepatitis C from alcohol consumption alone?

Answer: Hepatitis C was previously called "nonA-nonB hepatitis." It is a blood-borne disease and is not caused by drinking alcohol, although excessive alcohol consumption makes the liver damage worse. It is transmitted through infected blood.


23. I know that aspirin thins the blood, but what, in technical terms, does aspirin actually do to the blood?

Answer: Aspirin is able to prevent the clotting cells (platelets) in the blood from functioning properly.


24. Have there been any new developments in the treatment of Polycythemia Vera? I was told about six years ago that I had a "mild case" of this blood disease, and my blood is tested every three months. If my red blood count is over 45 they take a pint of blood. Usually the count is between 46 and 48. Is this still the best treatment or are there better ways of controlling the count?

Answer: Phlebotomy (periodic blood donation) is still the preferred treatment for Polycythemia Vera.


25. Is there a test for CJD (Creutzfeldt-Jakob Disease)? Also, how widespread is this disease in the U.S.?

Answer: CJD remains a rare disease in the U.S. There is no good test for this disease aside from biopsy of neurologic (brain) tissue.


26. Is it possible that some types of vitamins or minerals affect the white blood cell count? If not, what are other contributing factors to a low white blood cell counts?

Answer: Severe deficiencies of vitamins B12 or folic acid can cause a reduction in all blood cell types. Many other things including drugs, infections, and diseases of the marrow can also lead to a low white blood cell count.


27. Does a heart murmur have something to do with the blood? What is it?

Answer: A heart murmur is related to turbulence in the flow of blood in the heart. Patients with severely low red cell counts can have heart murmurs based on increased work by the heart.


28. What are the latest findings about the suspected causes or triggers of thrombotic thrombocytopenic purpura (TTP)? My wife nearly died of this disorder in 1985; her survival was due to plasmapheresis, which was then a relatively new therapy for TTP.

Answer: TTP is likely related to antibodies to, or a deficiency of, a protein that normally breaks down von Willebrand's factor. Von Willebrand's factor is a protein that causes platelets to stick together. Plasmapheresis has been used for the treatment of TTP for some time and is still the mainstay of therapy.


29. What is hemachromatosis and is it a common disease?

Answer: Hemachromatosis is a disease caused by excessive amounts of iron in the body. The iron deposits in the liver, heart, and endocrine glands, causing them to become dysfunctional. It is not an uncommon disease. Its estimated frequency in some populations is as high as 1 in 250 persons. It is less common among African Americans with an estimated frequency of 3 per 10,000 people.


30. What can we do to make sure our blood stays healthy; in other words, since it is produced in the bone, do we need to take nutrients to at least keep the bone healthy? Does drinking milk help with bone health? What about blood health, once it leaves its source?

Answer: Some vitamins and minerals are very important for maintaining healthy red blood cell production. These include iron, folic acid, B12, and B6. Bone health does not specifically improve blood health, but a healthy diet is recommended for good health in general.


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