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Exclusive: Colorado Doctors Skirt FDA Jurisdiction to Provide Stem Cell Therapies

March 10th, 2010 by admin

regenexx stem cell therapy from Centeno
Dr. Centeno is offering stem cell therapies for orthopedic damage with remarkable results. Is this the future of stem cells in the US?

The FDA has yet to approve stem cell therapies for general use in medicine, but that hasn’t stopped doctors in Colorado from providing them anyway. Chris Centeno and John Schultz have boldly formed Regenerative Sciences Inc. in Broomfield, Colorado. RSI provides its patients with the Regenexx procedure, an adult stem cell transplant that uses your own cells (autologous) to treat joint injuries and bone damage. There’s no surgery needed. A needle extracts bone marrow, RSI isolates the stem cells and cultures them in your own blood, and then these cells are injected into the area where they are needed. They’ve treated 348+ patients with 800+ injections and show no signs of slowing down. According to RSI’s own surveys, 89% of their knee patients showed marked improvement, as did 75% of their hip patients! Within months some patients can walk or run in ways they haven’t been able to in years. We’ve seen these kinds of results from stem cell treatments before, but only in horses and dogs. That’s because human stem cell therapies like this one aren’t approved by the FDA. How can Centeno and Schultz flaunt the lack of federal approval? They claim that Regenexx is solely used as a part of their medical practice, only within the state of Colorado, and as such is no more regulated by the FDA than it would be by the FAA or the Department of Motor Vehicles. I had a chance to talk with Dr. Centeno over the phone and learn more about Regenexx and RSI. For hundreds of patients, he and his team are providing a remarkable hope. They’ve brought lab-cultured medical stem cell therapies to the US. Finally.


Stem cells have been a focal point for hype and hope for years now. Besides healing horses and dogs, they have promising effects on diabetescorneal blindness, even HIV. It’s pretty clear that they’re also the future of organ transplants. Just the news of a stem cell related development or patent will cause a biotech company’s stocks to soar. The FDA, which regulates all interstate drug sales and related clinical trials is not trying to keep Americans from these “miraculous” cures, it’s simply trying to make sure they are safe first. Apparently, that’s taking too long. Medical tourism agencies are starting to cater to those seeking stem cell treatments. Whether or not they are ready for widespread medical use, stem cell therapies are in high demand, not just in the US but around the world. It’s no longer a question of when we will have access to these treatments, it’s a question of how.

regenexx stem cell knee therapy
A severely damaged knee healed to a remarkable degree. Must be stem cells. RSI is offering adult stem cell therapies in the US. That’s an important first, but what will happen without FDA approval?

Patient’s interested in the Regenexx procedure face what seems to be a fairly standard experience for autologous stem cell transplants. It takes 20-40 minutes to extract the cells from hip bone marrow with limited anesthesia, and blood is also taken. Over a month RSI’s lab will isolate mesenchymal (multipotent) adult stem cells and multiply them until they have 1 to 10 million. Typically, a patient will receive an injection into the treated area once a month for three months. Positive results are sometimes seen quickly (in 1 to 3 months) but will hopefully develop within 6 to 9 months. Importantly, there’s no down time as a result of the procedure. Patients can leave the clinic and go home after each injection.  A round of Regenexx (extraction, cultivation,  and 3 injections) costs $7000-$8500. Those who produce exceptional numbers of stem cells can use subsequent injections (even in other parts of the body) for around $3500. Most insurances will not cover the treatment.
The fact that RSI isolates and cultures (multiplies) the cells is a big difference from other clinics that offer stem cell therapies. That process allows the lab to create enough mesenchymal stem cells  to really have an effect on the area in which they are injected. Many clinics around the world will take blood, marrow, or tissue and then spin out the stem cells in a centrifuge, injecting them back in on the same day. That style  of therapy could possibly be effective, but it is far less likely than with a dose of millions of multipotent stem cells. There are several doctors around the US that will provide such ’single-visit’ stem cell therapies, but as far as I know RSI is the only that offers the lab cultured mesenchymal therapy in the US. Dr. Centeno has confirmed that he’s the only one, that he knows of, openly using this particular procedure in the US.
In the past, I have been very skeptical of stem cell treatment centers in other countries. I’d like to turn that same critical eye to Regenexx. It’s only fair. First, let’s look at the success RSI is selling. Autologous transplants are offered in the hands, hips, knees, shoulders, back (non-spinal cord injury), ankles, and bone fractures. For each of these procedures you can find many ardent and exceptionally encouraging patient testimonials on their website, or their YouTube channel, along with a flood of supportive media. Here’s a clip from a local news Channel which is pretty indicative of the rest:

Overall, RSI is claiming around 80% patient satisfaction according to its own surveys. That’s incredible, especially when you see some of their patients walking and running again on joints that have experienced years of chronic damage. It also seems Centeno and Schultz have the documented evidence to back up the claims for Regenexx’s success. RSI provides case studies for each of its treatments as well as published scientific research. According to my conversation with Centeno, RSI is currently working on a comprehensive statistical analysis of their more popular treatments so they can publish quantitative results in a peer review journal. In other words, they’ll soon publish the hard numbers – X% of patients feel Y% better Z months after the procedure.
Importantly, RSI seems to be upfront with patients about the limits of their own technique. The website FAQ clearly states that not all results will be like the testimonials, and they even have adedicated page explaining that stem cell therapies won’t work for everyone. Furthermore, RSI has published the largest study of risks and complications associated with stem cell treatments yet produced in the US (N=227). That paper demonstrates the very low harm associated with stem cell therapies – much lower than the alternative surgery(published in Current Stem Cell Research & Therapy). Centeno told me that if we’re really worried that autologous stem cell therapies are going to hurt someone, this paper pretty much shows they won’t.
The concerns most people have with RSI are not medical, they’re political. Many applaud Centeno and Schultz for supplying the public with the cutting edge technology they demand, but worry about the manner in which it has been accomplished. Skirting FDA approval for a technique through the arguments they use opens the gate to a host of problems. If RSI can provide Regenexx because it is a doctor’s procedure not involved in interstate commerce, does that mean someone else can do the same for another treatment? What are the limits of such procedures? How does a patient know if a doctor’s therapy is safe, or effective, if it hasn’t undergone peer review and government inspection?
During my conversation with Dr. Centeno, he pointed out that doctors and surgeons are developing new procedures all the time. Surgeons will often create new devices for their own use in surgery, doctors routinely try out new dosing regimes, or therapies on their patients. This is part of the medical profession.
Still, it’s possible that even though RSI is doing what many other doctors routinely do (develop a new therapy for use in their own practice) that the federal government could try to bring them to court. The FDA seems to have taken the stance that all stem cells (whether used autologously or not) are drugs. As such, they would need FDA approval, and would likely only be developed by large pharmaceutical companies.
According to Lee Buckler of Cell Therapy Blog, Centeno’s already received a warning letter from the FDA. Centeno clarified that this is actually an “untitled letter” which has no bearing on regulation. He pointed me to this explanation on untitled letters. RSI has faced concerns from the New York Department of Health, and went so far as to pursue a provisional license, even though they are no where near NY state. Clearly RSI is hoping to avoid bureaucratic problems or at least be very prepared for them if they do arise.  Perhaps with enough positive results they can avoid legal battles and even convince insurance companies to cover Regenexx.
Hopefully so. Just look as these results. They’re pretty damn amazing. If you accept the success rates, and the possibilities for long term healing…I know people who need this. I really want them to be able to get it.
Centeno says he is working with others to provide the framework through which many more patients could receive mesenchymal stem cell therapies. He’s on the board of the International Cell Medicine Society (ICMS) which is working to track stem cell therapy patients through a registry, as well as certify stem cell clinics for practice. Through conferences and seminars, doctors are trained in IVF to work in fertility clinics. Centeno explained to me that a similar practice could instruct and track physicians interested in providing lab cultured autologous stem cell therapies. In other words, the technique used by RSI could become a regularly seen procedure in specialty clinics across the country. That may mean more patients could have access to stem cells soon.
One way or another, I know they will. FDA approval is slow, but it’s coming. Athersys has a patent for a stem cell derived drug, other companies have therapies in clinical trials. Those treatments will be here some day. In the meantime, RSI is filling in the gap. Their work may even catch on as a trend. If largely successful, insurance companies may pay for it and the federal government may end up grandfathering Regenexx in at some point. It could happen. What’s certain is that the public demand for stem cell therapies is real, growing, and seemingly justified. When that sort of pressure for a technology exists nobody can keep it down.
**Update: It has been pointed out that we have neglected to consider the long term effects of stem cell therapies. This is an oversight on our part, but the reality is that there is no conclusive understanding of what the long term effects of stem cells treatments will be. We do not know if a stem cell treatment will be effective 5-10 years after it is administered, and we know of no large study that has conclusively reviewed patients for cancer, or any long term side effect 5-10 years after a stem cell injection. I believe that part of what ICMS is trying to do (reviewing clinics, tracking patients results over the long term) may yield a better understanding in the future.**
[image credit: Denver Business Journal, Regenerative Science Inc]
[video credit: ABC 7 News in Denver via Regenexx (copyright status unknown)]
[Sources: Regenerative Sciences Inc, ABC 7 News in Denver, Lee Buckler , RSI BlogCurrent Stem Cell Research & Therapy]

Nature Biotechnology Contents: Volume 28 pp 181 – 292

March 10th, 2010 by admin

NATURE BIOTECHNOLOGY

March 2010 Volume 28 Number 3, pp 181 – 292

Visit Nature Biotechnology online to browse the journal.

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Bioentrepreneur: an online resource for budding business in the life sciences.
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EDITORIALS
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America's got talent – can it keep it? p181
doi:10.1038/nbt0310-181
To remain competitive in biotech, policymakers should pay more attention to retaining skilled foreign workers than to fixating on illegal immigration.
http://links.ealert.nature.com/ctt?kn=104&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

H1N1dsight is a wonderful thing p182
doi:10.1038/nbt0310-182
Criticisms of the response of governments and of the pharmaceutical industry to the threat of the H1N1 epidemic are wide of the mark.
http://links.ealert.nature.com/ctt?kn=100&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

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NEWS
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Ark's gene therapy stumbles at the finish line pp183 – 184
Peter Mitchell
doi:10.1038/nbt0310-183
http://links.ealert.nature.com/ctt?kn=99&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Monsanto's alfalfa reaches Supreme Court p184
Boonsri Dickinson
doi:10.1038/nbt0310-184
http://links.ealert.nature.com/ctt?kn=101&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

GSK/Sirtris compounds dogged by assay artifacts pp185 – 186
Charlie Schmidt
doi:10.1038/nbt0310-185
http://links.ealert.nature.com/ctt?kn=50&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

US biodefense contracts continue to lure biotechs pp187 – 188
Catherine Shaffer
doi:10.1038/nbt0310-187
http://links.ealert.nature.com/ctt?kn=48&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Ride 'n Drive on government waste p188
doi:10.1038/nbt0310-188
http://links.ealert.nature.com/ctt?kn=46&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Melanoma vaccine for dogs p189
Suzanne Elvidge
doi:10.1038/nbt0310-189a
http://links.ealert.nature.com/ctt?kn=44&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Biotechs go virtual p189
Susan Aldridge
doi:10.1038/nbt0310-189b
http://links.ealert.nature.com/ctt?kn=57&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Chinese institute makes bold sequencing play pp189 – 191
John Fox and Jim Kling
doi:10.1038/nbt0310-189c
http://links.ealert.nature.com/ctt?kn=56&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

RNAi delivery shop p191
Nazlie Latefi
doi:10.1038/nbt0310-191a
http://links.ealert.nature.com/ctt?kn=52&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Brazil boosts bioscience p191
Ricardo Bonalume Neto
doi:10.1038/nbt0310-191b
http://links.ealert.nature.com/ctt?kn=51&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Patent income tax slashed p192
Asher Mullard
doi:10.1038/nbt0310-192a
http://links.ealert.nature.com/ctt?kn=60&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Abbott hit with record fine p192
Michael Francisco
doi:10.1038/nbt0310-192b
http://links.ealert.nature.com/ctt?kn=59&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Resuscitated deCODE refocuses on diagnostics p192
Mark Ratner
doi:10.1038/nbt0310-192c
http://links.ealert.nature.com/ctt?kn=11&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

NEWS FEATURES
One year in – Obama's biotech scorecard pp193 – 196
Jeffrey L Fox
doi:10.1038/nbt0310-193
As healthcare reform falters, the biotech industry awaits the fate of biosimilars and tax credits. Jeff Fox reports.
http://links.ealert.nature.com/ctt?kn=10&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

The lengthening handshake pp197 – 199
Randy Osborne
doi:10.1038/nbt0310-197
Although mergers and acquisitions (M&As) failed to hit the heights some analysts had predicted in 2009, a new type of tiered transaction rose to prominence[mdash]the structured deal. Randy Osborne reports.
http://links.ealert.nature.com/ctt?kn=9&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

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BIOENTREPRENEUR
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BUILDING A BUSINESS
Seeking the biotech eBay
Nuala Moran
doi:10.1038/bioe.2010.1
Internet exchanges suggest an easy route to sourcing and licensing technology, but can biotech intellectual property be packaged up and sold in this way?
http://links.ealert.nature.com/ctt?kn=8&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

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OPINION AND COMMENT
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CORRESPONDENCE
Oversulfated chondroitin sulfate is not the sole contaminant in heparin pp203 – 207
Jing Pan et al.
doi:10.1038/nbt0310-203
http://links.ealert.nature.com/ctt?kn=4&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Reply to Oversulfated chondroitin sulfate is not the sole contaminant in heparin pp207 – 211
doi:10.1038/nbt0310-207
http://links.ealert.nature.com/ctt?kn=3&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Why FDA recruitment of 'critics' is a problem p212
Henry I Miller
doi:10.1038/nbt0310-212a
http://links.ealert.nature.com/ctt?kn=2&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Genetic exceptionalism pp212 – 213
William Bains
doi:10.1038/nbt0310-212b
http://links.ealert.nature.com/ctt?kn=1&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

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FEATURES
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Lost in migration pp214 – 229
George S Mack and Andrew Marshall
doi:10.1038/nbt0310-214
Combinations of cytostatic treatments and chemotherapies currently in clinical practice offer limited hope for patients whose cancers have spread. But increasing understanding of the processes underlying metastasis may one day provide other therapeutic options.
http://links.ealert.nature.com/ctt?kn=7&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

PATENTS
Patenting biotech beyond the central dogma pp230 – 233
George Wu
doi:10.1038/nbt0310-230
Biotech inventors and patent practitioners alike need to be aware of new interpretations of what is considered patentable, and draft claims that extend beyond biological principles.
http://links.ealert.nature.com/ctt?kn=6&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Recent patent applications in DNA diagnostics p234
doi:10.1038/nbt0310-234
http://links.ealert.nature.com/ctt?kn=24&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

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NEWS AND VIEWS
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Genetic therapy for spinal muscular atrophy pp235 – 237
Alex MacKenzie
doi:10.1038/nbt0310-235
A severe inherited neuromuscular disease is corrected in mice by intravenous gene delivery.
http://links.ealert.nature.com/ctt?kn=26&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Targeting leukemia stem cells pp237 – 238
Hanna K A Mikkola, Caius G Radu and Owen N Witte
doi:10.1038/nbt0310-237
Acute myeloid leukemia stem cells can be made susceptible to chemotherapy by inducing them to divide.
http://links.ealert.nature.com/ctt?kn=25&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Cellular targets for influenza drugs pp239 – 240
Ji-Young Min and Kanta Subbarao
doi:10.1038/nbt0310-239
High-throughput RNAi screens in human cells suggest new approaches to curb influenza virus infection.
http://links.ealert.nature.com/ctt?kn=28&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Navigating genomic maps of cancer cells pp241 – 242
Marcel P van der Brug and Claes Wahlestedt
doi:10.1038/nbt0310-241
What can we learn from the first genome sequences obtained from cancerous cells?
http://links.ealert.nature.com/ctt?kn=27&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Grass genomics on the wild side p242
Craig Mak
doi:10.1038/nbt0310-242
http://links.ealert.nature.com/ctt?kn=18&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

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RESEARCH HIGHLIGHTS
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Research highlights p243
Markus Elsner, Laura DeFrancesco and Craig Mak
doi:10.1038/nbt0310-243
http://links.ealert.nature.com/ctt?kn=17&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

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COMPUTATIONAL BIOLOGY
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PRIMER
What is flux balance analysis? pp245 – 248
Jeffrey D Orth, Ines Thiele and Bernhard O Palsson
doi:10.1038/nbt.1614
Flux balance analysis is a mathematical approach for analyzing the flow of metabolites through a metabolic network. This primer covers the theoretical basis of the approach, several practical examples and a software toolbox for performing the calculations.
http://links.ealert.nature.com/ctt?kn=21&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

———————-
RESEARCH
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ARTICLES
Nutrient-sensitized screening for drugs that shift energy metabolism from mitochondrial respiration to glycolysis pp249 – 255
Vishal M Gohil et al.
doi:10.1038/nbt.1606
Many diseases are characterized by shifts in cellular energy metabolism. Gohil et al. use a quantitative, nutrient-sensitized screen to identify drugs that affect the relative rates of glycolysis and mitochondrial respiration, and demonstrate the protective capacity of an approved antiemetic in models of cardiac and cerebral ischemia.
Abstract: http://links.ealert.nature.com/ctt?kn=19&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0
Article: http://links.ealert.nature.com/ctt?kn=22&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Harnessing chaperone-mediated autophagy for the selective degradation of mutant huntingtin protein pp256 – 263
Peter O Bauer et al.
doi:10.1038/nbt.1608
Decreasing levels of mutant, but not normal, huntingtin (HTT) protein remains a major obstacle to treating Huntington's disease (HD). Bauer et al. show that a fusion of polyglutamine-and HSC70-binding motifs specifically targets mutant HTT for degradation by chaperone-mediated autophagy and ameliorates the phenotype of a mouse model of HD.
Abstract: http://links.ealert.nature.com/ctt?kn=71&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0
Article: http://links.ealert.nature.com/ctt?kn=72&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Directed evolution of a magnetic resonance imaging contrast agent for noninvasive imaging of dopamine pp264 – 270
Mikhail G Shapiro et al.
doi:10.1038/nbt.1609
Magnetic resonance imaging of hemoglobin in the brain can detect blood flow associated with neural activity, but direct imaging of neurotransmitters would provide a more sensitive measure of neural signal processing. Shapiro et al. use directed evolution to generate a protein probe that enables magnetic resonance imaging of the neurotransmitter dopamine.
Abstract: http://links.ealert.nature.com/ctt?kn=69&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0
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LETTERS
Rescue of the spinal muscular atrophy phenotype in a mouse model by early postnatal delivery of SMN pp271 – 274
Kevin D Foust et al.
doi:10.1038/nbt.1610
Spinal muscular atrophy is an autosomal recessive disease of motor neurons caused by lack of the SMN gene. Foust et al. achieve long-term correction of the disease phenotype in a mouse model by intravenous delivery of SMN using the viral vector scAAV9.
Abstract: http://links.ealert.nature.com/ctt?kn=67&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0
Article: http://links.ealert.nature.com/ctt?kn=68&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Induction of cell cycle entry eliminates human leukemia stem cells in a mouse model of AML pp275 – 280
Yoriko Saito et al.
doi:10.1038/nbt.1607
In acute myeloid leukemia, a sub-population of quiescent cancer cells, called leukemia stem cells, is thought to be responsible for chemotherapy resistance and eventual recurrence of the disease. Saito et al. show that treatment with granulocyte colony-stimulating factor can overcome resistance to standard therapy by inducing cell cycle entry of the leukemia stem cells.
Abstract: http://links.ealert.nature.com/ctt?kn=78&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0
Article: http://links.ealert.nature.com/ctt?kn=79&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

Isotopic labeling of terminal amines in complex samples identifies protein N-termini and protease cleavage products pp281 – 288
Oded Kleifeld et al.
doi:10.1038/nbt.1611
Many proteases are important drug targets, but identification of their substrates remains challenging. By using polymers to selectively isolate N-terminal peptides generated by proteolysis of complex samples, Kleifeld et al. identify substrates of clinically relevant proteases with broad specificity.
Abstract: http://links.ealert.nature.com/ctt?kn=75&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0
Article: http://links.ealert.nature.com/ctt?kn=77&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

———————-
CAREERS AND RECRUITMENT
———————-
The importance of foreign-born talent for US innovation pp289 – 291
Yeonji No and John P Walsh
doi:10.1038/nbt0310-289
A survey suggests that foreign-born scientists and engineers play a major role in scientific and innovation output in the United States.
http://links.ealert.nature.com/ctt?kn=93&m=34685620&r=MTc3MTg2NzE2NgS2&b=2&j=Njg2NDE4ODgS1&mt=1&rt=0

PEOPLE
People p292
doi:10.1038/nbt0310-292
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Nature Reviews Neurology – Table of Contents alert Volume 6 Issue 3

March 10th, 2010 by admin

NATURE REVIEWS NEUROLOGY

March 2010 Volume 6 Number 3

Visit Nature Reviews Neurology online to browse the journal.

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———————-
RESEARCH HIGHLIGHTS
———————-
Multiple sclerosis: Fingolimod is an effective oral treatment for MS
p121 | doi:10.1038/nrneurol.2010.6
http://links.ealert.nature.com/ctt?kn=80&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

IN BRIEF
Multiple sclerosis | Parkinson disease | Headache | Clinical trials
p122 | doi:10.1038/nrneurol.2010.11
http://links.ealert.nature.com/ctt?kn=34&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

Movement disorders: Image-based analysis reveals cause of parkinsonism
p122 | doi:10.1038/nrneurol.2010.9
http://links.ealert.nature.com/ctt?kn=89&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

Alzheimer disease: Amyloid-[beta] plaques and glucose metabolism in
early-onset AD
p123 | doi:10.1038/nrneurol.2010.10
http://links.ealert.nature.com/ctt?kn=65&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

IN BRIEF
Migraine | Epilepsy | Aging | Headache
p123 | doi:10.1038/nrneurol.2010.12
http://links.ealert.nature.com/ctt?kn=32&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

Alzheimer disease: Cancer link to Alzheimer disease, but not vascular
dementia
p124 | doi:10.1038/nrneurol.2010.7
http://links.ealert.nature.com/ctt?kn=68&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

Stroke: Common pathogens increase stroke risk
p124 | doi:10.1038/nrneurol.2010.8
http://links.ealert.nature.com/ctt?kn=62&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

———————-
NEWS AND VIEWS
———————-
Multiple sclerosis: Can retinal imaging accurately detect optic neuritis?
Elliot M. Frohman, Laura J. Balcer and Peter A. Calabresi
p125 | doi:10.1038/nrneurol.2010.13
A new study has compared the utility of optical coherence tomography and
visual evoked potentials in the diagnosis of optic neuritis-an inflammatory
condition that is frequently the presenting symptom of multiple sclerosis.
The results indicate that the two techniques can provide complementary
information for the diagnosis of this condition.
http://links.ealert.nature.com/ctt?kn=51&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

Parkinson disease: ADAGIO trial hints that rasagiline slows disease
progression
Cristina Sampaio and Joaquim J. Ferreira
p126 | doi:10.1038/nrneurol.2010.2
The results of the ADAGIO trial, combined with those of the TEMPO trial
and a large body of additional clinical and preclinical data, indicate
that the possibility of treatment with rasagiline should be discussed with
all patients with early Parkinson disease.
http://links.ealert.nature.com/ctt?kn=53&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

Migraine: Migraine with aura increases the risk of stroke
Ann I. Scher and Lenore J. Launer
p128 | doi:10.1038/nrneurol.2010.14
Migraine-in particular, migraine with aura-seems to confer an increased
risk of ischemic stroke and might also be linked with other cardiovascular
events. Findings from a new meta-analysis support the former association;
however, insufficient data exist to conclude whether this type of headache
increases the risk of nonstroke cardiovascular disease.
http://links.ealert.nature.com/ctt?kn=42&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

———————-
REVIEWS
———————-
Cerebrospinal fluid and plasma biomarkers in Alzheimer disease
Kaj Blennow, Harald Hampel, Michael Weiner and Henrik Zetterberg
Published online: 16 February 2010
p131 | doi:10.1038/nrneurol.2010.4
The early detection of Alzheimer disease might be critical to the
effectiveness of disease-modifying drugs, when such therapies become
available. In this Review, Blennow et al. examine the use of cerebrospinal
fluid and plasma biomarkers in the early diagnosis of this neurodegenerative
disorder. The authors also explore roles for cerebrospinal fluid biomarkers
in Alzheimer disease clinical trials.
Abstract: http://links.ealert.nature.com/ctt?kn=31&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0
Article: http://links.ealert.nature.com/ctt?kn=49&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

Hyperglycemia in acute ischemic stroke: pathophysiology and clinical
management
Nyika D. Kruyt, Geert Jan Biessels, J. Hans DeVries and Yvo B. Roos
Published online: 16 February 2010
p145 | doi:10.1038/nrneurol.2009.231
Individuals with acute ischemic stroke are frequently shown to have
hyperglycemia when admitted to hospital and elevated levels of blood
glucose are associated with a poor prognosis. Tight glycemic control (TGC)
might be an effective treatment for hyperglycemia in patients with acute
ischemic stroke; however, successful and safe provision of TGC is a
challenging task. This Review examines the evidence linking hyperglycemia
to unfavorable prognoses in patients with acute stroke, provides a systematic
review of the literature concerning TGC treatment after stroke and proposes
directions on how to treat hyperglycemia in patients with stroke.
Abstract: http://links.ealert.nature.com/ctt?kn=30&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0
Article: http://links.ealert.nature.com/ctt?kn=17&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

Environmental factors and their timing in adult-onset multiple sclerosis
Adam E. Handel, Gavin Giovannoni, George C. Ebers and Sreeram V. Ramagopalan
Published online: 16 February 2010
p156 | doi:10.1038/nrneurol.2010.1
Epidemiological data indicate that genetic and environmental factors
interact to determine an individual's risk of developing multiple sclerosis
(MS). Handel et al. examine the key periods of life during which the
environment might contribute to MS susceptibility, focusing on three
putative MS risk factors: sun exposure (and its relationship with vitamin
D levels), Epstein-Barr virus infection, and smoking.
Abstract: http://links.ealert.nature.com/ctt?kn=24&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0
Article: http://links.ealert.nature.com/ctt?kn=16&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

Behavior of spinal neurons deprived of supraspinal input
Volker Dietz
Published online: 26 January 2010
p167 | doi:10.1038/nrneurol.2009.227
Severe spinal cord injury (SCI) leads to dysfunction of the spinal neuronal
circuits that underlie locomotion and associated reflexes. In this article,
Volker Dietz discusses the time course of changes in the spinal circuitry
after SCI, and considers how an understanding of these changes might guide
the development of countermeasures to prevent neuronal dysfunction in the
chronic stage of SCI.
Abstract: http://links.ealert.nature.com/ctt?kn=29&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0
Article: http://links.ealert.nature.com/ctt?kn=8&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

———————-
CASE STUDY
———————-
The case of a 48 year-old woman with bizarre and complex delusions
Clement T. Loy, Jillian J. Kril, Julian N. Trollor, Matthew C. Kiernan,
John B. J. Kwok, Steve Vucic, Glenda M. Halliday and John R. Hodges
p175 | doi:10.1038/nrneurol.2010.3
In this article, Loy and colleagues examine the case of a woman with
frontotemporal dementia who presented in the clinic with complex delusions.
Psychosis is considered an unusual early feature of this form of dementia
but, when present, can wrongly suggest a diagnosis of schizophrenia. In
discussing the case, Loy et al. highlight the clinical features that might
assist in the differentiation between these two conditions.
Abstract: http://links.ealert.nature.com/ctt?kn=38&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0
Article: http://links.ealert.nature.com/ctt?kn=1&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

———————-
CORRESPONDENCE
———————-
Correspondence: Temporal lobe epilepsy is a progressive disorder
Neda Bernasconi and Boris C. Bernhardt
doi:10.1038/nrneurol.2009.82-c1
http://links.ealert.nature.com/ctt?kn=37&m=34684407&r=MTc2NDUyMzIwMwS2&b=2&j=Njg2MjcxNTYS1&mt=1&rt=0

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Ghosts

March 10th, 2010 by admin

Peel eased the black Toyota Prius off the M11 and continued on across Essex. Thank God he didn’t have to make this journey regularly like in the old days, before he started doing his programme via ISDN from Peel Acres. Still, it had been fun to visit some of the old watering holes in London. Walters would have enjoyed it. No-one had recognized him. Being dead had its compensations. Heart attack on a walking holiday in Peru? He’d thought no-one would ever believe that, but Pig said they would, and of course she was right. And no-one was going to look for him in the Essex badlands.

Pig would be asleep when he got back, but he’d get up early tomorrow and cook her breakfast. Couldn’t afford to sleep in tomorrow anyway, had to get the March edition of Dandelion Radio online before the weekend. The music was the main thing of course, as always. All those new bands straining to be heard. But it was fun pretending to be all the different DJs, especially the occasional fake Dutch accent. A heck of a lot more fun than working for the BBC, that was for sure. It had just got worse and worse over the years. Home Truths was the killer, nice idea but eventually he just couldn’t take the BBC bullshit any longer, and “death” had been a relief. Dandelion Radio was just about doing what he liked. A bit like the pirate days really, but totally legal. Of course, it didn’t pay, but radio had never been about the money. And no more Top of the Pops bollocks either, although it had paid for the original Peel Acres. Yes, he wished he’d discovered this internet thing years earlier. It might have kept him alive.

This is a work of fiction and any resemblance between the characters and persons living or dead is purely coincidental. Well, sort of. Oh, and Dandelion Radio, that’s real too.

Humana intro’s individual health insurance in Oklahoma: http://www.insurancebio.com/blog/humana-introduces-individual-health-insurance-in-oklahom.html

March 9th, 2010 by admin

Humana intro’s individual health insurance in Oklahoma: http://www.insurancebio.com/blog/humana-introduces-individual-health-insurance-in-oklahom.html

March 9th, 2010 by admin

Cooperative Behavior is Contagious: Reason to See Glass Half Full in Health IT Design

March 9th, 2010 by admin

In a study published in the March 8 early online edition of the Proceedings of the National Academy of Sciences, researchers from the University of California, San Diego and Harvard provide the first laboratory evidence that cooperative behavior is contagious and that it spreads from person to person to person. When people benefit from kindness they “pay it forward” by helping others who were not originally involved, and this creates a cascade of cooperation that influences dozens more in a social network.

The research was conducted by James Fowler, associate professor at UC San Diego in the Department of Political Science and Calit2’s Center for Wireless and Population Health Systems, and Nicholas Christakis of Harvard, who is professor of sociology in the Faculty of Arts and Sciences and professor of medicine and medical sociology at Harvard Medical School. Fowler and Christakis are coauthors of the recently published book “Connected: The Surprising Power of Our Social Networks and How They Shape Our Lives.”

Research by Fowler and Christakis – we’ll be examining early #getupandmove data using the social contagion research these two gents are publishing.

In addition to being fun, it’s evidence-based, yo!

Posted via web from Jen’s Posterous

Cooperative Behavior is Contagious: Reason to See Glass Half Full in Health IT Design

March 9th, 2010 by admin

In a study published in the March 8 early online edition of the Proceedings of the National Academy of Sciences, researchers from the University of California, San Diego and Harvard provide the first laboratory evidence that cooperative behavior is contagious and that it spreads from person to person to person. When people benefit from kindness they “pay it forward” by helping others who were not originally involved, and this creates a cascade of cooperation that influences dozens more in a social network.

The research was conducted by James Fowler, associate professor at UC San Diego in the Department of Political Science and Calit2’s Center for Wireless and Population Health Systems, and Nicholas Christakis of Harvard, who is professor of sociology in the Faculty of Arts and Sciences and professor of medicine and medical sociology at Harvard Medical School. Fowler and Christakis are coauthors of the recently published book “Connected: The Surprising Power of Our Social Networks and How They Shape Our Lives.”

Research by Fowler and Christakis – we’ll be examining early #getupandmove data using the social contagion research these two gents are publishing.

In addition to being fun, it’s evidence-based, yo!

Posted via web from Jen’s Posterous

23andMe – I may be beginning to understand . . .

March 9th, 2010 by admin

Whit Athey is one of those smart guys we all wish we were.    He’s a retired physicist with a doctorate in physics and biochemistry.    He wrote the Y Haplogroup Predictor that many of us use.    He also explains things.

I want to share his response to a recent question about 23andMe ‘matching’ on the ISOGG list.

The question was:

I am missing something in the definition of terms, apparently.    If each parent contributes 50% of his genes to the child, why isn’t the percentage more like 50% than 85%?

On the other hand, if as I think I have read, chimpanzees are 98% the same as humans, why isn’t the comparison of unrelated individuals more in the range of 98%?

If you can, please define the terms being used and explain why a parent and child comparison isn’t 50%.

Whit’s answer:

Yes, all humans are more than 99% identical at each base location.    This is confusing to a lot of people when they get involved with 23andMe data.    The half-million locations or SNPs that were chosen for the Illumina chip (that 23andMe uses) were chosen precisely because they are much more variable than the average location.    People, on average, are alike about 75% of the time at these particular 500,000 locations.    Therefore, being “75% similar on a genome-wide comparison” is just an artifact of the Illumina set of SNPs.    It would be very easy to select 500,000 locations where everyone would be 99% similar (500,000 random locations would probably do the trick), but it would not produce very interesting data.    It would probably be very difficult to find 500,000 locations where people would be only 50% similar  -    maybe impossible  -    I don’t know.

The “genome-wide comparison” is mostly meaningless as I said in my post the other day.    For this particular set of SNPs, you get “genome-wide comparisons” for siblings and parent-child results of around 84% and, of course, about 75% for unrelated people.    If we only had this measure to use, we would get nowhere fast.    It’s the long half-identical segments that are significant.

Maybe you would wonder how even the half-identical segments could be meaningful if there is a 75% probability of being identical anyway at a given location.    While that much is true for a single location, the probability that two consecutive locations would by chance alone have the same base is (0.75)(0.75) = .56 and the probability of 1000 consecutive SNPs having the same base by chance would be (.75)^1000 (to the 1000th power), which is such a small number that I hesitate to try to write it.    Therefore, when 23andMe finds a run of 1000 consecutive SNPs (adjacent on the same chromosome) that have the same state (on one of the chromosomes) they can reliably report that this is significant and could only occur as identical by descent.    The calculation is actually a little more complicated than that because you are comparing two bases for each SNP with two others in another person at each SNP.

Note that the SNP locations occur about every 6000 base locations on average, and the assumption is that if you have, for example, 1000 consecutive matching bases at the locations of the SNPs, then all the bases in between each consecutive pair of SNPs (the other 5999 out of the 6000) are assumed to be the same too, resulting in 6,000,000 consecutive matching bases.    These are the “half-identical segments.”

A parent passes along exactly 50% of his/her 22 autosomal chromosomes to his/her child, so you are right about that.    Depending on how the X and Y are counted in such calculations, you can see how the percentage would be moved slightly off 50%.    The X is much larger than the Y, so your father passes along just as many chromosomes as your mother, but the amount of DNA can be different for sons as for daughters.    I don’t actually know exactly how 23andMe calculates these things, but you can see the potential for some small differences from 50%

I may be beginning to understand . . .

23andMe – I may be beginning to understand . . .

March 9th, 2010 by admin

Whit Athey is one of those smart guys we all wish we were.    He’s a retired physicist with a doctorate in physics and biochemistry.    He wrote the Y Haplogroup Predictor that many of us use.    He also explains things.

I want to share his response to a recent question about 23andMe ‘matching’ on the ISOGG list.

The question was:

I am missing something in the definition of terms, apparently.    If each parent contributes 50% of his genes to the child, why isn’t the percentage more like 50% than 85%?

On the other hand, if as I think I have read, chimpanzees are 98% the same as humans, why isn’t the comparison of unrelated individuals more in the range of 98%?

If you can, please define the terms being used and explain why a parent and child comparison isn’t 50%.

Whit’s answer:

Yes, all humans are more than 99% identical at each base location.    This is confusing to a lot of people when they get involved with 23andMe data.    The half-million locations or SNPs that were chosen for the Illumina chip (that 23andMe uses) were chosen precisely because they are much more variable than the average location.    People, on average, are alike about 75% of the time at these particular 500,000 locations.    Therefore, being “75% similar on a genome-wide comparison” is just an artifact of the Illumina set of SNPs.    It would be very easy to select 500,000 locations where everyone would be 99% similar (500,000 random locations would probably do the trick), but it would not produce very interesting data.    It would probably be very difficult to find 500,000 locations where people would be only 50% similar  -    maybe impossible  -    I don’t know.

The “genome-wide comparison” is mostly meaningless as I said in my post the other day.    For this particular set of SNPs, you get “genome-wide comparisons” for siblings and parent-child results of around 84% and, of course, about 75% for unrelated people.    If we only had this measure to use, we would get nowhere fast.    It’s the long half-identical segments that are significant.

Maybe you would wonder how even the half-identical segments could be meaningful if there is a 75% probability of being identical anyway at a given location.    While that much is true for a single location, the probability that two consecutive locations would by chance alone have the same base is (0.75)(0.75) = .56 and the probability of 1000 consecutive SNPs having the same base by chance would be (.75)^1000 (to the 1000th power), which is such a small number that I hesitate to try to write it.    Therefore, when 23andMe finds a run of 1000 consecutive SNPs (adjacent on the same chromosome) that have the same state (on one of the chromosomes) they can reliably report that this is significant and could only occur as identical by descent.    The calculation is actually a little more complicated than that because you are comparing two bases for each SNP with two others in another person at each SNP.

Note that the SNP locations occur about every 6000 base locations on average, and the assumption is that if you have, for example, 1000 consecutive matching bases at the locations of the SNPs, then all the bases in between each consecutive pair of SNPs (the other 5999 out of the 6000) are assumed to be the same too, resulting in 6,000,000 consecutive matching bases.    These are the “half-identical segments.”

A parent passes along exactly 50% of his/her 22 autosomal chromosomes to his/her child, so you are right about that.    Depending on how the X and Y are counted in such calculations, you can see how the percentage would be moved slightly off 50%.    The X is much larger than the Y, so your father passes along just as many chromosomes as your mother, but the amount of DNA can be different for sons as for daughters.    I don’t actually know exactly how 23andMe calculates these things, but you can see the potential for some small differences from 50%

I may be beginning to understand . . .

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