Adult neurogenesis, the generation of new neurons in the adult brain, has become an important topic in neurobiology and is thought to be relevant to the way in which the brain repairs itself. However, for the most part, adult neurogenesis has been shown to be restricted to the dentate gyrus of the hippocampus and the subventricular zone. This paper reports the novel finding that adult neurogenesis may occur in the brainstem vestibular nucleus complex (VNC), an area of the brain that is not normally considered to be ‘neurogenic’, following a lesion of the vestibular nerve (unilateral vestibular neurectomy, UVN). The aim of this study was to quantify the proliferation of new cells in the VNC of the cat, determine whether they survive, and into …show more content…
1A). BrdU replaces thymidine in DNA when new DNA are generated during the S phase of the cell cycle and can be detected using a specific antibody; therefore BrdU labelling can serve as a measure of the proliferation of new cells. In these studies, 6 times points were used in order to characterise the time course of cell proliferation in the VNC after UVN. In order to determine whether newly proliferated cells actually survive (since they may be generated and die rapidly), in a second protocol, BrdU was injected at 3 days following UVN and then the brain tissue harvested at 27 days (see Fig. 1B). Lastly, proliferation of new cells does not necessarily equate to neurogenesis, the generation of new neurons. Therefore, in the third part of the study, labelling of the new cells with multiple antibodies (see Table 1) was used to determine whether they differentiated into neurons or other types of cells, and if neurons, what kinds of neurons. The authors report that cell proliferation increased in the VNC after UVN but not sham surgery, that many of the new cells survived, at least up to 27 days, and that some of these cells differentiated into microglial cells (labelled with OX-42 and BrdU), astrocytes (labelled with GFAP and BrdU) or neurons (labelled with NeuN or nestin and BrdU). Most of the neurons appeared to contain the neurotransmitter, GABA (labelled with GAD-67 and
Until recently there was virtually nothing doctors could do for the 500,000 Americans who have strokes each year, the 500,000 to 750,000 who experience severe head injury, or the 10,000 people who are paralyzed after spinal cord damage (3). However, that is about to change. Researchers now think it may be possible to replace destroyed brain cells with new ones to give victims of stroke and brain injury a chance to relearn how to control their body, form new thinking processes, and regain emotions. After demolishing the long-standing myth that brain cells cannot regenerate or proliferate, scientists are developing ways to stimulate cells to do just that. Although stroke, head injury, and paralysis are three of the most devastating things that can happen to anyone, scientists have recently learned that the damage they cause is not preordained. It takes place over minutes, hours, and days, giving them a precious opportunity to develop treatments to halt much of the damage. Most of the new remedies are not yet available, but an explosion of research in the last five to ten years has convinced scientists that some of them will work (8).
(1)The Scientist Magazine , Human neurogenesis. Group demonstrates that adult human brains grow new cells after all. http://www.the-scientist.com/
Stem cells are a type of unspecialized cells that can revive themselves through the process of cell division (Abdel-Salam and Oma, 2011). They have a phenomenal potential to differentiate into other specific cell types in a living organism. These cells can also be activated to turn into organ-specific cells or tissues with defined activity but only under specific experimental set-up. Stem cells have the ability to remain as they are or divide further to renew deteriorated and damaged tissue cells. Recently it has been discovered that stem cells can be used to treat Alzheimer’s disease, but still a lot of clinical trials are being conducted to find a specific government approved treatment.
Emerging evidence implicates microglial play critical roles to the CNS development of the brain. Microglial are unique population arise from immature yolk-sac macrophages that migrate and colonize the developing brain (Ginhoux et al., 2010; Ransohoff and Cardona, 2010). Interestingly, microglial (or their precursor cells) are selectively integrating into proliferative neurogenic zone of the proliferation and regulating the size of neural precursor cell pool via phagocytose neural precursor cell upon completion of neurogenesis(Cunningham et al., 2013). Also, colonization of microglia in the developing brain almost concurs temporally with brain vascularisation, neuroepithelial-radial glia transformation, neuronal migration, and myelination. Recent advent of transgenic technology and pharmacology allowed the role of microglia during development and their correlation with neural development disorder to be investigated extensively. For instance, pharmacologically knockout or inactivation of embryonic microglia resulted in increases of neural precursor cells pool (Cunningham et al., 2013). Similar phenomenons were also observed in genetically knockout of microglial in mice. Colony stimulating factor 1R-deficient (Csf1r−/−) mice w...
Sperry, R. W. (1963, October 15). Chemoaffinity in the Orderly Growth of Nerve Fiber Patterns and Connection. Natioanl Academy of Science, 50(4), 703-710.
In the article “Brain Gain: The Underground World of “Neuroenhancing” Drugs” (Yorker 2009) Margaret Talbot discusses the misuse of prescription drugs that enhance academic performance at the college level. First Talbot introduces readers to a young college history major at Harvard University named Alex who receives a description of a demanding, busy life which seems impossible to control without the safety unapproved adopted use of a drug named Adderall. After that Alex’s dependency on the prescription drugs cognitive enhancers is described when he asks his doctor to increase the amount of intake and the listing of his daily routine on using Adderall during a week that required him to write four term papers. Next Talbot describes a personal
Stem cells help us to maintain and heal our bodies, as they are undifferentiated cells, their roles are not yet determined. They have the ability to become anything during early life and growth. Stem cells come from two sources, namely: embryonic stem cells (embryo’s formed during the blastocyst phase of embryological development) and adult stem cells (see figure 3).
During early childhood, there is a huge proliferation of connections between neurons, usually peaking around the age of two. The adolescent brain then cuts down the amount of connections, deciding which ones are important to keep and which can be let go. While there are various theories as to the molecular mechanisms by which pruning actually occurs, most agree that pruning is primarily carried out by a very motile form of glial cell, called microglia [1], and pre-programmed cell death (apoptosis). These microglia are thought to remove cellular debris and perform surveillance during the healing process of an injured brain, but in the healthy, developing brain they have a possibly more important function. If a synapse receives little activity, it is weakened and eventually deleted by microglia and other glial cells through a process called long-term depotentiation (LTD). After the synapse has been removed, the space and resources that it once used are taken by other synapses. These synapses are strengthened by long-term potentiation (LTP). These processes and various others take place throughout development, peaking at adolescence and reaching their base around the age of 21, and transform the brain to create more complex and efficient neuronal configurations.
Sharp, J., Frame, J., Siegenthaler, M., Nistor, G., Keirstead, H.S. (2010). Human Embryonic Stem Cell-Derived Oligodendrocyte Progenitor Cell Transplants Improve Recovery after Cervical Spinal Cord Injury: Stem Cells, 28, 152 – 163.
Neurofibromatosis (NF) is a genetic disorder of the nervous system. This can cause tumors to form on the nerves anywhere in the body at any time. Neurofibromatosis affects all races, all ethnic groups and both sexes equally. NF if one of the most common genetic disorders in the United States. NF has three genetically distinct forms are NF1, NF2 and Schwannomatosis.
Alzheimer’s is a form of dementia that affects the brain. There is no cure for it but many treatments. Alzheimer’s is fatal and there are few stages of dementia. It is the 6th leading cause of death, more than 5 million Americans have it, and 15,5 million caregivers gave around 17.7 billion hours of unpaid care that cost around $220 billion in 2013. In my family, my grandmother who is 86 years old has very early stages of Alzheimer’s. She started having symptoms when she was 81. My grandfather took most of the care of her but as he got ill my aunt Kathy took over. When my grandfather got ill and had to be in 24 hour care, we all agree to put my grandmother in assisted living care 10 minutes from one of my aunt’s house.
Neurodevelopmental theory (NDT) informs clinical reasoning through the concepts of motor control, brain plasticity, motor learning and an understanding of functional human movement (Meadows & Williams, 2013). By identifying atypical movement patterns the therapist is able to select interventions, which will facilitate Sue in developing greater symmetry in her body and correct movement patterns. (Barthel, 2009; Feaver & Ezekiel, 2011). This influences the practice of interventions in NDT by applying moment-to-moment observations of Sue throughout treatment, in order to gage her reactions and adjusting interventions accordingly (Barthel, 2009). Barthel (2009) and Case-smith, Law, Missiuna, Pollock and Stewart (2010), defines NDT as a hand’s on approach to intervention, focusing on physically assisting Sue in the development of active and passive movement using key points of control during activities. This is used to facilitate Sue to engage in more normal movement patterns
Neurobiology is a theory that deals with the brain and your nerves. It determines if you are a left or right brain person. One of the theorists is named Roger Sperry. He was a very big neurobiologist. A disease that deals with this theory is ADD/ADHD.
As the human body goes through different experiences, the brain grows, develops, and changes according to the environmental situations it has been exposed to. Some of these factors include drugs, stress, hormones, diets, and sensory stimuli. [1] Neuroplasticity can be defined as the ability of the nervous system to respond to natural and abnormal stimuli experienced by the human body. The nervous system then reorganizes the brain’s structure and changes some of its function to theoretically repair itself by forming new neurons. [2] Neuroplasticity can occur during and in response to many different situations that occur throughout life. Some examples of these situations are learning, diseases, and going through therapy after an injury.
Most of the body’s functions such as, thinking, emotions, memories and so forth are controlled by the brain. It serves as a central nervous system in the human body. The mind is the intellect/consciousness that originates in the human brain and manifests itself in emotions, thoughts, perceptions and so forth. This means that the brain is the key interpreter of the mind’s content. Jackson and Nagel seem to resist identifying what we call “mental events” with brain events, for different reasons, while J.J.C. Smart takes the opposing view.