Interesting article. What's special about this is that it represents functional, not anatomic, imaging of the brain. Bedside neonatal head imaging is currently dominated by ultrasound, useful in identifying areas of hemorrhage most common in preemies. MRI is also useful in neonates, but again usually looking for hemorrhage or abnormalities of brain morphology.
This technique uses light attenuation to measure oxygen consumption in the brain. Hemoglobin (Hb) is the oxygen-carrying molecule in blood. It can bind up to 4 oxygen molecules, and in this configuration is called oxyhemoglobin. When unbound, it's called deoxyhemoglobin. The technique they've developed can measure relative concentrations of the two forms of Hb allowing the computation of areas of increased metabolic activity or brain activity. The article boils down to being able to show increased activity in the upper extremity motor cortex when the researchers moved the kids' arms.
In this sense, the technique is more like PET or functional MRI (fMRI) imaging, and appears to be a visual analog to EEG, or electroencephalography, commonly used by neurologists to identify seizure foci. Instead of a series of squiggly lines (think polygraph test), this actually gives you a series of slices of the brain with color demonstrating the area of activity.
Clinically, this won't replace ultrasound or MRI, but it will provide more information about brain function. This may help determine an infant's prognosis after the ultrasound has already demonstrated a hemorrhage, or assist a neurosurgeon trying to eliminate a seizure focus.
I use large (21" and greater) B&W LCD and CRT monitors at work for ~8 hours/day, switching every month or so between the two types. I find that when I'm using the LCDs, the pictures seem sharper and brighter, but I seem to end up with daily eyestrain and headaches.
Part of it may be the ergonomics of my workstations, I suppose, but I don't think they're too different. Anybody else have a similar experience?
I don't have a problem with patents on new technology to make new discoveries any more than I have a problem with patenting a more efficient internal combustion engine. Sequencers (specifically the one mentioned in the article from the original post) are really just a more advanced way of interpreting an old sequencing technique:
First, you partially chop up the length of DNA in question using commercially available enzymes. This produces a bunch of segments of different lengths which you then label with 4 different fluorescent tags (each color is specific for one particular base -- A, C, T, or G). You then load these segments into a thin, flat gel. An electric current is applied to the gel, and DNA (being negatively charged) moves toward the positive terminal (small segments move more quickly than long ones). Each segment, on its way to the end of the gel, is illuminated by a laser and the resulting color is noted by a detector. The sequence is then reconstructed by computer based on the colors passing through the detector in a specific order.
The technique was first figured out in 1977 by Frederick Sanger (it's called the Sanger Dideoxy sequencing method). There's a similar method that works by base destruction described by Maxam and Gilbert around the same time. Big difference now is that you don't have to read the gells with their hundreds of little bands by hand anymore... and that's where the sequencers come in. Imagine sequencing the human genome by hand...
(Too bad there aren't any prices there... the one that we had in my old lab was over $100,000 though...)
The more disturbing trend to me is patenting the genes themselves... you can patent the camera that takes my picture, but don't patent the stuff that makes me me.
Yup, I'm planning on it. (: I still have one question though: will the PS2 DVD player be able to decode Dolby Digital or DTS? I think I read somewhere that the PS2 will have 6 audio outputs...
I disagree... we have a list of genes and sequences of the genes, which is potentially a powerful tool. We may not be able to model systems perfectly, but what we can do is look at a tissue sample and determine what genes are malfunctioning and possibly the mutations that are causing the malfunctions. Granted, this is kind of a 'shotgun' approach to science -- it ain't elegant -- but it will definitely help us get a better picture of the real causes of disease. Take cancer as an example... we don't really have genes pegged as the causes of most cancers, and a lot of cancer research centers around guessing what genes might disregulate cell growth, then spending years sequencing those genes and seeing what mutations are in them... using a complete gene map combined with DNA chip technology (or something like it) could focus research efforts as well as identifying unknown genes that are a sort of 'common denominator' for cancer.
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Interesting article. What's special about this is that it represents functional, not anatomic, imaging of the brain. Bedside neonatal head imaging is currently dominated by ultrasound, useful in identifying areas of hemorrhage most common in preemies. MRI is also useful in neonates, but again usually looking for hemorrhage or abnormalities of brain morphology.
This technique uses light attenuation to measure oxygen consumption in the brain. Hemoglobin (Hb) is the oxygen-carrying molecule in blood. It can bind up to 4 oxygen molecules, and in this configuration is called oxyhemoglobin. When unbound, it's called deoxyhemoglobin. The technique they've developed can measure relative concentrations of the two forms of Hb allowing the computation of areas of increased metabolic activity or brain activity. The article boils down to being able to show increased activity in the upper extremity motor cortex when the researchers moved the kids' arms.
In this sense, the technique is more like PET or functional MRI (fMRI) imaging, and appears to be a visual analog to EEG, or electroencephalography, commonly used by neurologists to identify seizure foci. Instead of a series of squiggly lines (think polygraph test), this actually gives you a series of slices of the brain with color demonstrating the area of activity.
Clinically, this won't replace ultrasound or MRI, but it will provide more information about brain function. This may help determine an infant's prognosis after the ultrasound has already demonstrated a hemorrhage, or assist a neurosurgeon trying to eliminate a seizure focus.
I use large (21" and greater) B&W LCD and CRT monitors at work for ~8 hours/day, switching every month or so between the two types. I find that when I'm using the LCDs, the pictures seem sharper and brighter, but I seem to end up with daily eyestrain and headaches.
Part of it may be the ergonomics of my workstations, I suppose, but I don't think they're too different. Anybody else have a similar experience?
Thought it sounded fishy...
... or a Saturn Vue
First, you partially chop up the length of DNA in question using commercially available enzymes. This produces a bunch of segments of different lengths which you then label with 4 different fluorescent tags (each color is specific for one particular base -- A, C, T, or G). You then load these segments into a thin, flat gel. An electric current is applied to the gel, and DNA (being negatively charged) moves toward the positive terminal (small segments move more quickly than long ones). Each segment, on its way to the end of the gel, is illuminated by a laser and the resulting color is noted by a detector. The sequence is then reconstructed by computer based on the colors passing through the detector in a specific order.
The technique was first figured out in 1977 by Frederick Sanger (it's called the Sanger Dideoxy sequencing method). There's a similar method that works by base destruction described by Maxam and Gilbert around the same time. Big difference now is that you don't have to read the gells with their hundreds of little bands by hand anymore... and that's where the sequencers come in. Imagine sequencing the human genome by hand...
Check out http://www.ornl.gov/hgmis/faq/seqfacts.html for more information about sequencing techniques and the genome project in general.
For the gadget geeks among us: http://www.pebio.com/ga/dna/377specs.html
(Too bad there aren't any prices there... the one that we had in my old lab was over $100,000 though...)
The more disturbing trend to me is patenting the genes themselves... you can patent the camera that takes my picture, but don't patent the stuff that makes me me.
Yup, I'm planning on it. (: I still have one question though: will the PS2 DVD player be able to decode Dolby Digital or DTS? I think I read somewhere that the PS2 will have 6 audio outputs...
I disagree... we have a list of genes and sequences of the genes, which is potentially a powerful tool. We may not be able to model systems perfectly, but what we can do is look at a tissue sample and determine what genes are malfunctioning and possibly the mutations that are causing the malfunctions. Granted, this is kind of a 'shotgun' approach to science -- it ain't elegant -- but it will definitely help us get a better picture of the real causes of disease. Take cancer as an example... we don't really have genes pegged as the causes of most cancers, and a lot of cancer research centers around guessing what genes might disregulate cell growth, then spending years sequencing those genes and seeing what mutations are in them... using a complete gene map combined with DNA chip technology (or something like it) could focus research efforts as well as identifying unknown genes that are a sort of 'common denominator' for cancer.