C
CAT (or CT) Scan - A diagnostic, computerized imaging system that uses X-Rays to determine the density of different spots in the body. By producing a picture of the densities at thousands of spots in the Brain, a CT scan discloses normal and abnormal structures. However, all MR techniques provide superior imaging resolutions. #25
CD4+ - A specific, Genetically determined type of T-Cell, that is thought to play a primary role, in MS & EAE. It is also known as a Helper T-Cell; because it activates all Acquired Immune Responses, only if it recognizes, the presented MHC Class II complex. #27
Cell - The body is made up almost entirely of many different kinds of Cells. Each Cell has a discrete inner core called the Nucleus, surrounded by CytoPlasm, and is encased in a Membrane separating it from other Cells. #09
Cell Membrane - The thin layer made of Proteins, Fats and Carbohydrates, which form the capsule of a Cell, and is its outside "Skin". #01
Cellular Immunology - Also called Adaptive or Acquired Immunity is one part of the body's Immune System. Its chief componet is the Cytoxic T-Cell, which recognizes and destroyes any Cell that is infected with a Virus, or a Bacteria, and it can directly kill Tumor Cells. #09
Central Nervous System - The part of the Nervous System covered by the Meninges. It includes the Brain, Spinal Cord, and Optic Nerves. #25
- The Nervous System comprises the Brain and Nerves:
- Afferent Nerves (from the Latin: ad = towards; ferro = I carry), which carry Sensory impulses from all parts of the Body to the Brain
- Efferent Nerves (ex = from; ferro = I carry) through which "Messages" are conducted from the Brain to the Muscles and all of the Organs of the Body
- The Somatic part of the Nervous System has Sensory components which convey Sensations from the Eyes, the Nose and other Sensory Organs to the Brain, and Motor components transmitting impulses to the Skeletal Muscles in the Limbs and Trunk permitting Voluntary control of Movements.
Centrocecal Scotoma - A Blind Spot that interferes with Central Vision, because part of what you should see does not register - due to DeMyelination, along the Optic Nerve. #25
Cerebellum - Part of the Brain, located above and behind the BrainStem, it regulates Balance and Coordination of Movements. It has no direct connection to any specific movement, rather it is the primary regulator of all movements. Hence damage to the Cerebellum or its inputs is one cause of Posture Imbalance and Gait problems.
- The Cerebellum can not re-learn non-voluntary movements, since these routines are hard-wired; but the repetition of motions employed in balance training, usually enable the substitution of compensating, unimpaired pathways to work around the deficit.
- Cerebellar disease is evidenced as Complex Motor Dysfunctions: changes in Speed and Cadence of Speech (Scanning Speech); Willed Movements resemble Tremor; and Eye Movement abnormalities (Nystagmus, Oscillopsia).
- Mild Cerebellar Dysfunction
The inability to judge the range of limb movements, without watching them.
- Severe Cerebellar Dysfunction
The inability to perform limb movements smoothly and efficiently, even while watching them. #01, #22, #02
Cerebellar Function Disorders
The severity of symptoms is directly proportional to the amount of tissue destroyed - NOT on the specific location of damage. Among the most characteristic signs of Cerebellar damage are the following:
Asthenia - a lack of muscular strength, either during Voluntary Muscle Contraction or in Holding Posture.
Ataxia - incoordination of muscular activity involving Tremor, failure of progression, and failure accurately to perform rapid alternating movements, such as tapping a finger. A swaying, unsteady, and wide based gait is often the most obvious sign.
Dysmetria - literally is difficulty measuring. Dysmetria is the failure to stop a motion at the intended point, with overshoot occurring (ex: the finger to nose test). This Cerebellar miscalculation is either from output failures or faulty inputs.
Fatigability - muscles on the same side, where Cerebellar damage has occurred, tire more easily and have slower than normal contraction and relaxzation times, producing slowed movements.
Hypotonia - muscles feel flabby and offer less resistance to passive displacement. This may be from lack of response to Spinal Tract input.
CerebroSpinal Fluid (CSF) - The fluid surrounding the Brain and the Spinal Cord, containing Glucose (sugar), Proteins, and other substances that are also found in Blood. However, CerebroSpinal Fluid (CSF) does not normally contain Red or many White Cells. CSF is filtered from the blood supply and secreted by a vascular membrane (Choroid Plexus), within the Lateral, Third and Fourth Ventricles of the Brain. #09, #21
Cerebrum - Forms the great bulk of the Brain, it is divided into two Hemispheres, which occupy the entire vault of the Cranium and are incompletly seperated from each other by a deep median cleft, The Longitudinal Cerebral Fissure. #16
Chemokinesis - Indicates general movement, of many different cell types.
Chemotaxis - Litterly means directed locomotion. It refers to the trail of secreted Cytokines that lead various Leukocytes, to a site of Inflammation.
Circumduction - A pattern of moving the Legs in which the person swings the upper Leg widely at the Hip. It is usually caused by partial Paralysis or Spasticity of the Limb. #25
Clonus - Involuntary movement of rapidly alternating contraction and relaxation of a muscle. Ankle Clonus is the most common form of Clonus. Reflexive Spasms in the Calf Muscles, cause the Foot and Leg to bounce up and down, when the Knee is bent and the toes are on the floor. Clonus is a hallmark Sign of Spasticity. #19, #01
(Also See: Neurological Examination)
Cognition - High level functions carried out by the human Brain, including: Comprehension and use of Speech, Visual Perception and Construction, Calculation Ability, Attention (information processing), Memory, and Executive Functions such as Planning, Problem-Solving, and Self-Monitoring. #28
Complement - Nine Serum proteins activated in sequence by an Antigen, forming Antigen-AntiBody-Compound. (Symbol 'C'). It is part of the Non-Specific Immune System that generally deals with Bacteria infections. #09
- Complement upregulates Macrophage Cells, aiding their ability to find and digest foreign cells. It also calls Neutrophil Cells to the scene, which can kill Bacteria by producing Peroxide.
(Also See: The Complement System
Computed Tomography - See: CAT Scan.
Coordination - An organized working together of muscles and groups of muscles aimed at bringing about a purposeful movement, such as walking or standing. #28
Corpus Callosum - Is a thick band of more than 300 million Myelinated transverse Nerve fibers. The Corpus Callosum is the largest and most important Commissural Fiber that interconnects the two Cerebral Hemispheres. It lies at the bottom of the Longitudinal Cerebral Fissure and is a very frequent site for MS Lesions. #16
- The Corpus Callosum's underside forms the roof of the two Lateral Ventricles; its front terminates in the Frontal Lobes and is named the Forceps Anterior or (Minor). The back portion (the Forceps Posterior or Major) connects to the Temporal and Occipital Lobes and to the Hippocampus Bands - Peduncles of the Corpus Callosum. #14
Cortex - Is the outer layer of any organ. #01
Cortex, Cerebral - The outer layer of Nerve Cells that covers the entire surface of the Cerebral Hemispheres. Thinking and other Complex Neuronal Activity occur in the Cerebral Cortex. #01
- A 2.5 to 4.0 mm. thick layer of Neurons containing Gray Matter. #20
Cortex, Association - The Cortex immediately adjacent to and closely connected to The Primary Sensory Cortex. Association Cortex gives form and meaning to raw Sensory messages received at the Primary Sensory Cortex thru widespread connections to many parts of both sides of the Brain. #01
Cortisone - A Steroid Hormone recommended to some with Multiple Sclerosis, to reduce acute inflammations in the CNS. Cortisone treatments carry significant risks and should NOT be used for long term treatment. #25
Cytokines - Are proteins (usually GlycoProteins) of relatively low molecular mass and usually consist of a single chain. Cytokines are signaling chemicals secreted by various Leukocytes to activate other cells, coordinate, and regulate all important biological processes: Cell Growth, Immunity, Cell Activation, Inflammation, Tissue Repair, Fibrosis and MorphoGenesis.
- Cytokine Mechanisms:
- Autocrine - effects only the producing cell
- Endocrine - travel through the bloodstream, acting on numerous distant cells
- Paracrine - acts locally on target cells, adjacent to the producing cell
- Some Cytokines (ie: IL-8) are Chemotactic for specific cell types, and are also called *Chemokines*. Although Cytokins are considered to be a Family, this is a Functional rather than a Structural concept; these Proteins are not all chemically related. (ex: Interferons, Tumor Necrosis Factor, and InterLeukins). #30
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