Search results
Results from the WOW.Com Content Network
In MDDS associated with mutations in RRM2B that primarily affect the brain and muscle, there is again hypotonia in the first months, symptoms of lactic acidosis like nausea, vomiting, and rapid deep breathing, failure to thrive including the head remaining small, delay or regression in moving, and hearing loss. Many body systems are affected.
A mutation cannot be recognized by enzymes once the base change is present in both DNA strands, and thus a mutation cannot be repaired. At the cellular level, mutations can cause alterations in protein function and regulation. Mutations are replicated when the cell replicates.
The hallmark symptom of LATE is a progressive memory loss that predominantly affects short-term and episodic memory. [1] This impairment is often severe enough to interfere with daily functioning and usually remains the chief neurologic deficit, unlike other types of dementia in which non-memory cognitive domains and behavioral changes might be noted earlier or more prominently. [1]
Some procedures, such as brain biopsies of people with Rett syndrome, usually call for a fresh tissue sample that can only be extricated from the brain of deceased individual. In such cases, the researchers have no control over the age of brain tissue sample, thereby limiting research options.
Damage in the brain is widespread, and affects many domains of functioning. [19] [a] Loss of acetylcholine-producing neurons is thought to account for degeneration in memory and learning, while the death of dopamine-producing neurons appears to be responsible for degeneration of behavior, cognition, mood, movement, motivation, and sleep. [2]
Particularly, one division within the ventral striatum, the nucleus accumbens core, is involved in the consolidation, retrieval and reconsolidation of drug memory. [9] The caudate nucleus is thought to assist in learning and memory of associations taught during operant conditioning. Specifically, research has shown that this part of the basal ...
Differentiated somatic cells of adult mammals generally replicate infrequently or not at all. Such cells, including, for example, brain neurons and muscle myocytes, have little or no cell turnover. Non-replicating cells do not generally generate mutations due to DNA damage-induced errors of replication.
These structures therefore enable and control brain arousal (as determined by metabolic or electrical activity) and are necessary neural correlates. One such example is the heterogeneous collection of more than two dozen nuclei on each side of the upper brainstem (pons, midbrain and in the posterior hypothalamus), collectively referred to as ...