• Autograft. This means cells that obtained from one part of the body of an individual and then transplanted into another part of the body. Auto means "to oneself". Heterograft means cells that are obtained from one person (animal) and transplanted to another person (animal). Xenografts means cells that are obtained from another species, i.e. a pig, and transplanted to human.

• Axon. Axon refers to a single nerve fiber that comes from a Neuron. It is part of the neuron. When the axon is injured, the part of the axon that has been separated from the neuron cell body dies.

• Chondroitinase. This is a bacterial enzyme that dissolves a family of proteins called chondroitin-6-sulfate proteoglycans (CSPG). Bacteria secrete this enzyme when they infect tissues. CSPG has been shown to inhibit axonal growth and Regeneration. Chondroitinase was recently reported to improve regeneration in animals.

• Ensheathing. This refers to the unusual tendency of cells to ensheath or wrap around other cells. In the case of olfactory ensheathing cells (OEC), they wrap around axons. These cells are sometimes called olfactory ensheating glial (OEG) cells because they often express a marker of Glial Cells called glial fibrillary acidic protein (GFAP).

• Fetal. This means the cells were obtained from aborted fetuses, usually in the second trimester. Note that fetal stem cells are not the same as embryonic stem cells which are derived from blastocysts, the earliest stage of development during the first two weeks after the egg is fertilized.

• Glia. These are cells in the Central Nervous System that perform several important functions. There are many kinds of glial cells. The most abundant kind of glial cell is called Astrocyte. The first and most important function of astrocytes to separate the central nervous system from other tissues. Astrocyte send processes that completely line blood vessels, link up with each other, and form a tight barrier called the blood-brain-barrier. They keep molecules from the body from entering the brain. Astrocytes also regulate the extracellular Environment of central nervous tissues and secrete factors that sustain neurons, including GDNF (see neurotrophin). Other kinds of glial cells include oligodendroglia which are special glial cells that myelinate axons in the central nervous.

• Immune rejection. The immune system in our body recognizes foreign cells, tumors, or infections. Immune cells include lymphocytes and macrophages. The lymphocytes needs to come into contact with the cells and become activated. One activated, they release cytokines and other signals to attract other cells and activate them to produce antibodies or kill the cells. Immune suppression means to take drugs that prevent activation of the immune system.

• Myelin. These are membranes that wrap many times around axons and allow them to conduct signals more rapidly and reliably. Axons that have myelin around them are myelinated. In the central nervous system, axons are myelinated by oligodendroglia (see glia) that typically myelinate as many as 20 axons at a time. Axons in the Peripheral nervous system are myelinated by Schwann Cells. Olfactory ensheating cells will wrap around axons (ensheath) but will also form myelin. Schwann cells and olfactory ensheathing cells will myelinate only one axon at a time.

• Neural stem cells. These are stem cells from the central nervous system that can make many kinds of cells. In fetal brains, these cells are called radial glial cells and located in the cortex. In neonatal or adult brains, these cells are located at the base of the brain, in a place called subventricular zone (SVZ) but a stream of these cells migrate to the hippocampus (a part of the brain responsible for memory) and to the olfactory bulb. Although neural stem cells are believed to be present in the brainstem and spinal cord, neither their identity or location are known.

• Neurotrophins. These are a family of molecules that stimulate the growth of neurons. The original neurotrophin was a molecule called Nerve Growth Factor (NGF) discovered in the 1960's and it stimulates peripheral axons (as well as sensory axons in the central nervous system). Subsequently, several other neurotrophins were discovered, includ brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and neurotrophin-4 (NT-4). Glial derived neurotrophic factor (GDNF) is secreted by glial cells in the central nervous system.

• Olfactory. This refers to the part of your nose and neural structures responsible for the sense of smell. The olfactory mucosa is situated on the roof of your nasal cavity. The olfactory nerve leads from the olfactory mucosa to the olfactory bulb, the part of the brain the receives smell sensations.

• Omentum. This is a vascular structure that surrounds your stomach and intestines. It is responsible for sending blood vessels that supply and carry away food. Because the omentum is an actively growing tissue, it will vascularize (send blood vessels) into tissues. Several doctors have used omentum transplants on the spinal cord.

• Peripheral nerve. These are the nerves that go from your central nervous system to other parts of the body. Peripheral nerves are defined by the presence of Schwann cells. For example, the nerve that goes from the brain to the eye (retina) is a central nerve because it does not have Schwann cells. Likewise, the olfactory nerve is considered a central nerve because it does not contain Schwann cells. However, other cranial nerves such as the nerves that go from the brain to the muscles of the eyes or throat are considered peripheral nerves because they contain Schwann cells. The peripheral nerve contains some Schwann cells and some cells that separate bundles of axons.

• Rolipram and cAMP. Rolipram is a drug that blocks an enzyme called phosphodiesterase 4 (PDE-4). PDE-4 breaks down a molecule called cyclic AMP or cAMP. cAMP is an intramessenger that carries out many functions, including increasing excitability and growth of cells. Recent studies suggest that when cAMP levels are high in growing axons, they will ignore molecules in the tissue that might inhibit axonal growth.

• Schwann cells. These are cells that are responsible for myelinating peripheral nerves. In many ways, they look and behave like olfactory ensheathing glia except that brain cells recognizes them as foreign cells and will tend to form barriers around them. Schwann cells generally do not migrate well when transplanted into the brain.

• Stem cells. These cells are pluripotent, i.e. can produce many different kinds of cells. There are three types of stem cells. One is embryonic stem cells that are obtained from blastocysts (the earliest stage of embryonic development); these cells are not only pluripotent but can continue to produce cells indefinitely in culture. Fetal stem cells are from fetuses, usually from the brain or some other tissues. In adults, two types of stem cells have been extensively studied: neural stem cells and mesenchymal stem cells (usually found in blood or bone marrow). Umbilical cord blood cells are probably mesenchymal stem cells as well.

[This message was edited by Wise Young on 02-21-05 at 02:22 PM.]
Original post may be found here...
http://carecure.atinfopop.com/4/OpenTopic?a=tpc&f=3854088921&m=635108091