Apheresis

The term Apheresis is Greek in origin and it means 'to take away'. This is a medical technology wherein the blood of a donor/patient is passed through an apparatus that separates one particular required component. The separated portion is withdrawn and the remaining components are retransfused into the patient/donor. The components thus separated from the patient/donor includes, plasma, platelets or leukocytes. This procedure is adhered to as an extracorporeal therapy.

In the process of apheresis, whole blood is removed from the patient/donor. The components of whole blood are separated by a centrifuge or an instrument specially designed for this purpose. The apheresis procedure is often employed to obtain stem cells from peripheral blood of patients suffering leukemia, a blood disease. Stem cells are infused into the patient's blood stream in order to produce cells that eventually will mature into red blood cells, white blood cells and platelets.

In transplants such as bone marrow procedures, the sick person happens to be his/her own donor. Blood is drawn and at a later time reinfused into that patient's blood stream in a procedure known as autologous bone marrow transplant. When stem cells are obtained from a healthy person, the procedure is allogeneic bone marrow transplant. Here, another person, may or may not be related, is the donor. Apheresis has become essential in providing blood components for several types of therapies. The process of apheresis takes a couple of hours and the volunteer donor/patient undergoes apheresis to supply specific components.

Leukapheresis is the removal of PMNS (Polymorphonuclear leukocytes), basophils and eosinophils for transfusion into patients whose PMNs are ineffective or in whom the traditional line of therapy has failed. LDL apheresis is the removal of low density lipoprotein in patients suffering from hypercholesterolemia. Erythrocytapheresis is the collection of red blood cells (RBCs) either two standard units of RBCs or one unit plus either plasma or platelets. This process is commonly known as 'double reds' or 'double red cell apheresis'.

Apheresis is used in stem cell harvesting for circulating bone marrow cells during transplantations. To collect sufficient stem cells, apheresis process is performed for at least two consecutive days, although at times five or even more procedures become necessary.

It is pertinent to understand that when apheresis system is adopted for therapy, the system is removing relatively small amounts of fluid, not more than 10.5 mL/kg body weight. That fluid which is removed must be replaced in order to maintain the intravascular volume.
The apheresis process is painless. Some patients/donors may experience lightheadedness, numbness or tingling of the nose, lips or fingers. These symptoms are short lived and treatable. Possible complications include bleeding in needle sites, thrombosis or clotting in blood vessels, or rarely surgical complications if a temporary apheresis catheter is inserted. Infection is always a risk as this procedure involves penetrating the skin and open access to blood vessels.

Myelodysplastic Syndrome

Myelodysplastic syndrome or MDS refers to a group of blood disorders caused by defective blood cell production in the bone marrow. Bone marrow produces immature blood cells called blasts, which over a period of time develop into mature blood cells and divide themselves into red blood cells, white blood cells and platelets. In Myelodysplastic syndrome, these blasts fail to mature and either die in the marrow itself or soon after they reach the blood stream. When there are not enough healthy blood cells, the body becomes weak and is susceptible to infections. MDS is not a cancer, however, in 20 to 30% of patients, the condition may progress itself into cancer and thus this condition was earlier called preleukemia.

Causes of Myelodysplastic syndrome

Based on causes, Myelodysplastic syndrome can be classified into primary MDS and secondary MDS. Myelodysplastic syndrome presenting itself without any known cause is called primary MDS. Myelodysplastic syndrome may also occur due to some known reasons such as history of cancer treatment involving radiation and chemotherapy, exposure to certain industrial chemicals and smoking. When the cause of the MDS condition is known, it is called secondary Myelodysplastic syndrome. Identifying the type of MDS is vital to the treatment as primary MDS has better prognosis when compared to secondary MDS.

Symptoms

Myelodysplastic syndrome does not cause any symptoms in the initial stages of the disease. However, the following warning signs may show up as the disease starts to progress.

• Fatigue due to anemia
  
• Frequent infections due to damaged immune system
  
• Shortness of breath
  
• Paleness
  
• Easy bruising or bleeding can occur due to low platelet count.
  
• Small red spots just under the skin.
  

Diagnosis and treatment

MDS is diagnosed with the help of blood tests and bone marrow tests. A complete blood test is done to understand the different blood counts. However, blood tests alone cannot detect MDS. Bone marrow tests are conducted to confirm the presence of Myelodysplastic syndrome. This procedure involves taking bone marrow samples from the pelvic bone of the patient by inserting a needle under local anesthesia. Once MDS is determined, the following methods are followed to treat the condition.

• Chemotherapy drugs
  
• Blood transfusion to treat anemia and low platelet count.
  
• Using medications called growth factors to allow the bones marrow to make more blood cells.
  
• Antibiotics to treat infections
  
• Stem cell transplant, an option that promises a cure to MDS, yet not widely adopted, as not many candidates qualify for this method. This method involves destroying the existing cells in the bone marrow via chemotherapy and radiation and infusing the stem cells from the donor.
  

Aging

Like machines all creatures have built in obsolescence. As we age we will experience progressive loss of physiological capacity. Starting with decline in sensory perception like hearing loss (Presbycusis), decrease in Visual acuity (Presbyopia), declining hormone levels, loss of muscle mass and bone mass, aging takes a toll on our health slowly but steadily. Atherosclerosis results in inflammation and vascular changes which in turn increases the risk for cardiac issues, cerebrovascular issues, peripheral vascular disease and cognitive impairment. This biological deterioration is considered a major risk factor for cancer, cardiovascular diseases, diabetes and Alzheimer’s disease among others. Unlike the loss of physical strength due to aging, Brain aging does not happen at a uniform rate. Age related Cognitive impairment depends on a number of factors such as education, mental stimulation, physical exercises, religious conviction, bonding with family and friends.

Aging Process

At the cellular level, there are 2 key hallmarks of the aging process: shortening of telomere length and cellular senescence. Telomeres,sequences of DNA located at the end of the chromosomes maintain genomic stability. Telomeres shorten during mitosis (replication) and this shortening of Telomeres is thought to be the cause of several diseases, low physical performance/endurance and cortical thinning of the brain. Shortening of Telomeres can be the direct result of inheritance but other factors play a larger role such as :

• Stress
  
• Lack of exercise, sedentary life style
  
• Excessive Body Mass Index
  
• Smoking
  
• Excessive Alcohol consumption
  
• Drug Abuse
  
• Chronic inflammation
  
• Vitamin/Mineral Deficiency
  
• Oxidative Stress
  

Cellular Senescence : The primary purpose of senescence is to prevent propagation of damaged cells by triggering their elimination via the immune system. But the accumulation of senescent cells with aging reflects either an increase in the generation of these cells or the elimination of these cells.

Recent research indicates that there are several drugs and some life style changes can reduce the telomere shortening rate. Diets and supplements play a role as much as a rigorous exercise regimen. There are drugs and supplements which show great potential in slowing down the onset of age related diseases. Resveratrol, a powerful auto-oxidant found in large quantities in red wine is one such agent. Resveratrol has helped slow down aging in animals in some research. Resveratrol supplements have shown promise in reducing the age related cognitive decline, improve general health conditions by lowering bad cholesterol and lowering inflammation.

Other drugs such as rapamycin and metformin have shown some potential in slowing down aging process in a different way. But these drugs have not been approved outside the labs to have any impact at this time.

Hyperbaric oxygen therapy (HBOT) is a technique where placing the subject in an oxygen rich chamber (100% oxygen in an environmental pressure higher than one absolute atmosphere) to enhance the amount of oxygen dissolved in body's tissues.HBOT can induce cognitive enhancements through positive changes in cerebral blood flow. Some studies indicate that HBOT can induce the expression of hypoxia induced factor (HIF), vascular endothelial growth factor and sirtuin (SIRT), stem cell proliferation, mitochondrial biogenesis, angiogenesis and neurogenesis.

Hyperbaric oxygen therapy is considered as a regular treatment option for non-healing wounds, radiation injuries, hypoxic or ischemic events (carbon monoxide toxicity) and some infections.