CNS Diseases and Disorders
purepedantry | August 17, 2009The abstract says it all:
Zombies are a popular figure in pop culture/entertainment and they are usually portrayed as being brought about through an outbreak or epidemic. Consequently, we model a zombie attack, using biological assumptions based on popular zombie movies. We introduce a basic model for zombie infection, determine equilibria and their stability, and illustrate the outcome with numerical solutions. We then refine the model to introduce a latent period of zombification, whereby humans are infected, but not infectious, before becoming undead. We then modify the model to include…
purepedantry | June 24, 2009I wanted to draw attention to a new paper in JAMA recently because it reveals a lot about how conditional most of the statements we make in behavioral genetics are. Every time you hear a news article that says, "Gene for depression found," I want you to think about this case.
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Risch et al. performed a meta-analysis on 14 studies that were looking at Serotonin Transporter (5-HTTLPR) genotype and number of stressful life events. These two factors were related to the subsequent risk for developing clinical depression. Their analysis found -- contrary to a very well known study,…
neurotopia | September 25, 2008Some people have been noticing erratic behavior from republican nominee John McCain lately. His most recent seems to be slight, but rather odd. Specifically, he appears to have developed ptosis--- a drooping eyelid--- which could of course be related to any number of causes, from an autoimmune attack on cholinergic receptors such as that seen in myasthenia gravis, to diabetes.
Ptosis can also be the result of a brain tumor that affects the oculomotor nerve (cranial nerve III). Sudden development of the condition at old age following multiple bouts of melanoma (which has a penchant for…
neurotopia | January 14, 2008Memantine is the most recent weapon in the fight against Alzheimer's. There's been a lot of hype surrounding the drug because....
The first-generation of compounds aimed to boost the brain's acetylcholine levels led to the development of drugs such as Aricept⢠(donepezil) and Excelon⢠(rivastigmine). Attempts to develop drugs that block the action of glutamate by a considerable number of pharmaceutical companies and researchers were not successful for a long time, since these receptors are also required for normal brain function, learning and memory in particular. It was therefore…
neurotopia | November 15, 2007Abel over at Terra Sigillata got is writ in a tinger over bad grammar and was concerned that Alzheimer's Disease had been tied to risky sexual behavior. His conclusion was that he got a poorly worded email notice about two separate problems that were linked inappropriately by a semicolon. So everything's fine, all clear, right? He's free to engage in risky sexual behavior without fear of getting Alzheimer's Disease (AD) later in life!
That's not entirely true.
We've known that inflammation plays a huge role in the Alzheimer's disease process. Unfortunately, inflammation is caused by a…
neurotopia | September 7, 2007...but for those who suffer from it, "in your head" can be more debilitating than other chronic, painful illnesses. A massive WHO survey study of 60 countries reported that 3.2% of people had depression over the course of a year. Interestingly, though...
This was a bit lower than for asthma (3.3 percent), arthritis (4.1 percent), and angina (4.5 percent), and higher than for diabetes (2.0 percent.)
But the results of a quality-of-life index called the "global mean health score" showed that depression was, by a significant margin, the most difficult to bear.
The most difficult to bear, and…
neurotopia | August 29, 2007Finally we get some data on changes in AD pathology with statin use! Statins are taken for lowering cholesterol, but they have other beneficial effects such as modulating inflammatory responses. Thus, they could prove beneficial in the treatment of AD given the disease has a significant inflammatory component.
According to the press release
The two changes in the brain that are considered the most definitive hallmarks of Alzheimer's are brain "plaques" and "tangles." After controlling for variables including age at death, gender, and strokes in the brain, the researchers found…
neurotopia | July 18, 2007Yes, that title is a bit ostentatious. But the foods we eat contain many compounds that can be beneficial to brain health. One strategy for optimizing our brains for long-term peak performance is to identify these compounds and discover how they are beneficial. Head-healthy chemicals have previously been isolated from curries and spices before, and it looks like we've found another curcuminoid, bisdemethoxycurcumin, which may be useful in combating Alzheimer's Disease:
Researchers have isolated bisdemethoxycurcumin, the active ingredient of curcuminoids -- a natural substance found in…
neurotopia | July 5, 2007This is the third part in an overview of menopause and hormone therapy. Parts one and two are here and here. This time around I describe changes in cognitive and behavioral profiles for women and animal models of menopause. I may decide to expand on a handful of studies at a later date, but for now I wanted to provide a very brief overview of human studies, problems inherent to human studies, and animal studies. I think the next part of this series will focus on the quality of our animal models and what they have to tell us. But for now, anyone who is interested in these issues knows where…
neurotopia | November 19, 2006Temporal lobe epilepsy (TLE) refers to a condition where recurrent seizures arise in the temporal lobe of the brain. This condition is seen in humans and animals. Often, TLE arises following a neural insult such as head trauma or tumor, but can also be triggered by infection. These febrile seizures are often seen in children under the age of five, and subsequent scans can show atrophy of temporal lobe structures such as the hippocampus. The hippocampus is highly interconnected with other temporal lobe structures, so a seizure that originates from or propagates through the hippocampus is…
neurotopia | August 21, 2006Looks like yet another interesting toxin was found, this time in a venomous snail. This discovery comes from the lab of an old player in the field, who apparently discovered the conotoxin that is used in Prialt.
McIntosh says the OmIA toxin will be useful in designing new medicines because it fits like a key into certain lock-like "nicotinic acetylcholine receptors" found on nerve cells in the brain and the rest of the nervous system.
"Those are the same types of receptors you activate if you smoke a cigarette," he says, explaining that nicotine in cigarette smoke "binds" to the receptor to…
neurotopia | July 28, 2006Amyotrophic Lateral Sclerosis is a devastating disease that claims the upper and lower motor neurons, and ultimately the lives of most patients within 3-5 years of diagnosis, usually from respiratory failure. Patients lose control of voluntary muscles as the pathways that innervate them degenerate. Lou Gehrig and Stephen Hawking are two famous ALS patients.
Now a group suggests that antisense oligonucleotide therapy may be used to effectively treat some forms of the disease.
Some forms of ALS are heritable. A subset of these cases are caused by a mutation to the enzyme superoxide…
neurotopia | July 25, 2006Mixing Memory brings up some excellent points regarding mirror neurons in primates, and Frontal Cortex follows up with his thoughts. To both of them I say "bravo, but your skepticism probably doesn't go far enough".
We give Rizzolatti et al too much credit with their conclusions. After all, they've only demonstrated the existence of mirror neurons in monkeys. Due to the obvious inherent difficulties associated with recording from human neurons in vivo, no one has yet (to my knowledge) published anything that demonstrates the existence of mirror neurons in people. Instead, we stick…
neurotopia | July 19, 2006The difficulty with treating spinal cord injuries arises from a number of factors. Firstly there is the primary damage to the axons of the spinal cord itself, resulting in mechanical damage that can inhibit neurotransmission and transport of cellular material to and from the distal cord. The damaged cord must also compensate for secondary damage such as the generation of free radicals, a lack of oxygen to the affected area (anoxia), glial scarring, and a host of other issues.
Your typical spinal neuron looks like this.
(Image snagged from http://www.steve.gb.com). The axon is a long…
neurotopia | July 16, 2006Shelley mentioned a study last week that suggested more and more young people are getting Parkinson's Disease, and she wondered whether there was any utility in blaming our industrialized society based on the fact that certain compounds we produce can induce Parkinsonian symptoms. Let's start by giving a brief overview of the systems involved before we attempt to answer that question.
The substantia nigra contains a collection of dopaminergic neurons that project to the striatum. Integrity of this pathway is essential for normal motor function, although this nigrostriatal system is capable…
neurotopia | July 8, 2006A highly conserved set of genes known as the sirtuin family are known to be activated by caloric restriction (CR) and extend the lifespan of a number of species. CR may also reduce the risk of Alzheimer's Disease, and can prevent the formation of amyloid plaques in transgenic mouse models of AD. The question, then, is whether sirtuin gene activation is a mechanism through which CR can prevent AD pathology, and what genes/compounds are involved in this particular biochemical cascade. Since I'm writing this post, you can probably guess that I've found an article that addresses this very…
neurotopia | June 9, 2006...you might not know what to do
you might have to think of
how you got started
sittin' in your little room
--The White Stripes
Welcome to the second incarnation of Neurotopia! The old incarnation can be found here, although lately it has just been a collection of posts where I complain about how Blogger stinks. But no more! Now I'm here on this slick new platform! The SEED overlords pulled a mean trick on me: they set up the new blog launch mere hours before I'm supposed to hit the road and celebrate my 8th anniversary by accompanying Mrs. Evil Monkey to Fallingwater for the weekend.…