Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Studying stem cells will help us understand how they transform into the dazzling array of specialized cells that make us what we are. Some of the most serious medical conditions are due to problems that occur somewhere in this process. A better understanding of normal cell development will allow us to understand and perhaps correct the errors that cause these medical conditions.
Another potential application of stem cells is making cells and tissues for medical therapies. Today, donated organs and tissues are often used to replace those that are diseased or destroyed. Unfortunately, the number of people needing a transplant far exceeds the number of organs available for transplantation. Pluripotent stem cells offer the possibility of a renewable source of replacement cells and tissues to treat a myriad of diseases, conditions, and disabilities including, amyotrophic lateral sclerosis, spinal cord injury, burns, heart disease, diabetes, and arthritis.
SOURCE: National Institutes of Health, Stem Cell Information. Stem Cells and Diseases.
What are stem cells?
Stem cells are cells that have the potential to develop into many different
or specialized cell types. Stem cells can be thought of as primitive,
"unspecialized" cells that are able to divide and become specialized cells of
the body such as liver cells, muscle cells, blood cells, and other cells with
specific functions. Stem cells are referred to as "undifferentiated" cells
because they have not yet committed to a developmental path that will form a
specific tissue or organ. The process of changing into a specific cell type is
known as differentiation. In some areas of the body, stem cells divide regularly
to renew and repair the existing tissue. The bone marrow and gastrointestinal
tract are examples areas in which stem cells function to renew and repair
tissue.
The best and most readily understood example of a stem cell in humans is that
of the fertilized egg, or zygote. A zygote is a single cell that is formed by
the union of a sperm and ovum. The sperm and the ovum each carry half of the
genetic material required to form a new individual. Once that single cell or
zygote starts dividing, it is known as an embryo. One cell becomes two, two
become four, four become eight, eight to sixteen, and so on; doubling rapidly
until it ultimately creates the entire sophisticated organism. That organism, a
person, is an immensely complicated structure consisting of many, many, billions
of cells with functions as diverse as those of your eyes, your heart, your
immune system, the color of your skin, your brain, etc. All of the specialized
cells that make up these body systems are descendants of the original zygote, a
stem cell with the potential to ultimately develop into all kinds of body cells.
The cells of a zygote are totipotent, meaning that they have the capacity to
develop into any type of cell in the body.
The process by which stem cells commit to become differentiated, or
specialized, cells is complex and involves the regulation of gene expression.
Research is ongoing to further understand the molecular events and controls
necessary for stem cells to become specialized cell types.
Why are stem cells important?
Stem cells represent an exciting area in medicine because of their potential
to regenerate and repair damaged tissue. Some current therapies, such as bone
marrow transplantation, already make use of stem cells and their potential for
regeneration of damaged tissues. Other therapies are under investigation that
involves transplanting stem cells into a damaged body part and directing them to
grow and differentiate into healthy tissue.
Leukemia is a type of cancer of the blood cells in which the growth and development of the blood cells are abnormal. Strictly speaking, leukemia should refer only to cancer of the white blood cells (the leukocytes) but in practice it can apply to malignancy of any cellular element in the blood or bone marrow, as in red cell leukemia (erythroleukemia).
Diabetes mellitus is a chronic condition characterized by high levels of sugar (glucose) in the blood. The two types of diabetes are referred to as type 1 (insulin dependent) and type 2 (non-insulin dependent). Symptoms of diabetes include increased urine output, thirst, hunger, and fatigue. Treatment of diabetes depends on the type.
Arthritis is inflammation of one or more joints. When joints are inflamed they can develop stiffness, warmth, swelling, redness and pain. There are over 100 types of
arthritis including osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, lupus, gout,
and pseudogout.
Parkinson's disease is a slowly progressive neurologic disease characterized by a fixed inexpressive face, a tremor at rest, slowing of voluntary movements, a gait with short accelerating steps, peculiar posture and muscle weakness, caused by degeneration of an area of the brain called the basal ganglia, and by low production of the neurotransmitter dopamine. Most patients are over 50, but at least 10 percent are under 40.
Cancer is a disease caused by an abnormal growth of cells, also called malignancy. It is a group of 100 different diseases, and is not contagious. Cancer can be treated through chemotherapy, a treatment of drugs that destroy cancer cells.
Heart disease (coronary artery disease) is caused by a buildup of cholesterol deposits in the coronary arteries. Risk factors for heart disease include smoking, high blood pressure, heredity, diabetes, peripheral artery disease, and obesity. Symptoms include chest pain and shortness of breath. There are a variety of tests used to diagnose coronary artery disease. Treatment includes life-style changes, medications, procedures, or surgery.
Burns are categorized by severity as first, second, or third degree. First degree burns are similar to a painful sunburn. The damage is more severe with second degree burns, leading to blistering and more intense pain. The skin turns white and loses sensation with third degree burns. Burn treatment depends upon the location, total burn area, and intensity of the burn.
Amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease) is a neurological disease that progresses rapidly. The disease attacks the nerve cells responsible for the control of voluntary muscles. Early symptoms include cramping, twitching, or stiffness of the muscles; slurred nasal speech; difficulty swallowing or chewing, and muscle weakness in an arm or leg. Currently, the cause of ALS is not known. ALS is a fatal disease. No cure has been found for ALS, however, the drug riluzole (Rilutek) is FDA approved, and this drug reduces the damage to motor neurons by decreasing the release of glutamate.
When vertebrae are broken or dislocated, the result can cause traumatic injury to the spinal cord. A spinal cord injury can have significant physiological consequences. One indication of the severity of a spinal cord injury are respiratory complications. Spinal cord injuries are classified as either complete or incomplete. A spinal cord injury can affect breathing, lead to pneumonia, low blood pressure, irregular heart beat, blood clots, spasms, autonomic dysreflexia, bed sores (pressure sores), chronic pain, bladder and bowel problems, and reproductive and sexual function issues. Rehabilitation and recovery of a spinal cord injury is dependant upon the type of injury.
Retinitis pigmentosa (RP) is a genetic condition that causes retinal degeneration and eventual vision loss. Symptoms include night blindness and tunnel vision. Visual field testing and electrophysiological testing are essential in diagnosing RP. Though there is no cure for RP, vitamin A therapy and an omega-3-rich diet may be recommended for patients to slow disease progression.
Coronary artery disease is the most common cause of death in the United
States. Over a million people each year will have a heart attack and 25% will
die before they get to the hospital while or in the Emergency Department.
Prevention is the key to treatment of heart disease.
Diagnosis of heart disease is often made by careful history taken by a health care
practitioner.
Some individuals may have atypical symptoms, including almost none at all.
The testing strategy to confirm the diagnosis and plan appropriate
treatment needs to be individualized for each patient diagnosed with heart
disease.
Treatment of heart disease depends upon the severity of disease, and is often directed by the
symptoms experienced by the affected individual.
Introduction to heart disease
The heart is like any other muscle, requiring oxygen and nutrient-rich blood for it t...
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