Health posts

January 29, 2010
12:01 AM
803 views

Friday Weird Science: Getting carpal tunnel could be more fun than you think

So after that whole myth about sex in space got thrown around and it turned out to be bunk (well, ok, I'm calling it bunk until I see the report my ownself, and I was SO happy to be able to say "sex...in...spaaaaaaaaaaaaaaaaaaace...". Blah), I figure I owe you guys some REAL Friday Weird Science. Or at least, a really amusing hypothesis.

Ah, Journal of Medical Hypotheses. Where would we be without the hilarious, half-baked meanderings of people who submit their lightly-supported ideas to a journal with no peer-review?

I would like to dedicate this post to my laboratory manager. She is totally hilarious, and went through some rough surgery for carpal tunnel a few years ago. And now she's going to go through an even MORE rough time as I mock her for the next few years about how she GOT the carpel tunnel. Mwah-ha-ha-ha...

Kudos also go out to NCBI ROFL, who pointed me towards this paper in the first place. What's up, guys.

John Zenian. 'The role of sexual intercourse in the etiology of carpal tunnel syndrome' Medical Hypotheses, 2010.

Read the rest of this post... | Read the comments on this post...... Read more »

Zenian, J. (2010) The role of sexual intercourse in the etiology of carpal tunnel syndrome. Medical Hypotheses. DOI: 10.1016/j.mehy.2009.12.015

January 28, 2010
07:47 PM
551 views

An Intriguing View of Alzheimer's Disease

by Reason in Fight Aging!

Alzheimer's research is a field in constant flux; no unifying theory of Alzheimer's biochemistry goes unchallenged, there are a great many such theories coming and going, and much remains to be discovered or proven. Conversely, so much money flows into Alzheimer's science that new results are constantly emerging to sway the picture in one direction or another. This is science at its messiest, which is usually also where it is most interesting, and most likely to soon deliver a firm, defensible theory. A large fraction of the Alzheimer's research community focuses in some way on forms of amyloid or other aggregates that build up in the brain: why is it there, what is the mechanism by which it causes harm, how can we get rid of it safely, is it a cause or secondary marker of other harmful mechanisms, and so forth. On that topic, I noticed an interesting article from earlier this month that places Alzheimer's in a spectrum with other, similar neurodegenerative conditions: Studies demonstrate link among Alzheimer's disease, Down syndrome and atherosclerosis all Alzheimer's disease patients harbor some cells with three copies of chromosome 21, known as trisomy 21, instead of the usual two. Trisomy 21 is...... Read more »

Granic A, Padmanabhan J, Norden M, & Potter H. (2009) Alzheimer A{beta} Peptide Induces Chromosome Mis-Segregation and Aneuploidy, Including Trisomy 21; Requirement for Tau and APP. Molecular biology of the cell. PMID: 20032300

January 28, 2010
11:31 AM
592 views

Presence of prion proteins in non-neuronal tissue in a case of variant CJD

by Brian Appleby in CJD Blogger

A recent article in the journal PLOS One describes a novel finding of abnormal prion proteins (PrPres) in additional non-neuronal tissues of a variant CJD (vCJD) patient. The study comes from the National Prion Disease Pathology Surveillance Center, located at Case Western University in Cleveland, Ohio. Prior to this study, there was evidence that PrPres was present in some non-neuronal tissues as shown below. The present study examined other tissues for the possible presence of PrPres. Tissue samples were obtained from a patient with vCJD whose illness onset was within the U.S.A., but was likely acquired in the U.K. The autopsy examination used sodium phosphotungstate precipitation to detect the presence of PrPres. Immunohistochemistry was conducted with the monoclonal antibody 3F4 to the PrP residues 109-112. The presence and absence of PrPres in various tissues are summarized below. Several interesting findings include the presence of PrPres in the kidneys but not the bladder. This is pertinent because small amounts of PrPres have been detected in the urine of animals with prion disease. Also, the two organs are made of different cell types. The urinary bladder is composed of transitional cells, while the kidneys have a small amount of this type of cell. PrPres was also detected in the uterus and ovary, which poses the potential of vertical transmission. Although vertical transmission of BSE has been demonstrated in animals, there has been no evidence of this occurring in humans. These are important findings and they underscore the potential for transmission of vCJD, which we already know can occur in some blood products. Unfortunately, these findings do not tell us anything about the likelihood of transmission as the presence of PrPres has not always equated infectivity. This patient also had a prolonged survival time (32 months), which may have affected the extent of non-neuronal tissue propagation of PrPres. Technorati Tags: prion,variant CJD,vCJD,neuropathology,public health,biology,medicine Notari, S., Moleres, F., Hunter, S., Belay, E., Schonberger, L., Cali, I., Parchi, P., Shieh, W., Brown, P., Zaki, S., Zou, W., & Gambetti, P. (2010). Multiorgan Detection and Characterization of Protease-Resistant Prion Protein in a Case of Variant CJD Examined in the United States PLoS ONE, 5 (1) DOI: 10.1371/journal.pone.0008765 ... Read more »

Notari, S., Moleres, F., Hunter, S., Belay, E., Schonberger, L., Cali, I., Parchi, P., Shieh, W., Brown, P., Zaki, S.... (2010) Multiorgan Detection and Characterization of Protease-Resistant Prion Protein in a Case of Variant CJD Examined in the United States. PLoS ONE, 5(1). DOI: 10.1371/journal.pone.0008765

January 28, 2010
05:30 AM
401 views

Santa's OK! Over 70 and overweight possibly a good idea.

by Yoni Freedhoff in Weighty Matters

There have been a number of studies of late that have concluded that being overweight (not obese, overweight) and elderly is in fact a good combination.Well, here's another.This study, published today in the Journal of the American Geriatric Society has Leon Flicker and his colleagues discussing the impact of weight on mortality over a 10 year period in 9,240 Australian men and women.Their findings?The minimum mortality risk was found at a BMI of 26.6 and as BMI decreased from there, risk increased, with the risk of death with a BMI at the lower end of the "normal" range being nearly double the risk of those who were "overweight". These results were sustained even when stratified into groups of initially "healthy" versus initially "unhealthy" subjects and when years one, two and three were subtracted from the study to eliminate those who might have lost weight prior to enrolment due to a chronic illness.The one variable aside from weight that had a tremendous impact was being sedentary. Men who were sedentary were found to have a 28% increased risk of mortality across all weight categories while for women the risk was double!Class I Obese participants had very similar mortality risks to normal weight individuals though as weight went up from there, so too did risk.The results aren't exactly surprising. Previous studies have shown the same results and certainly the theory that older folks carrying some excess weight will have greater metabolic reserves to draw on to weather both chronic and acute medical conditions sounds feasible.The main limitation of this paper is that BMI was used as a surrogate measure of body fat. This becomes problematic in a geriatric population due to both the natural course of aging (loss of muscle and conversion to fat) as well as the fact that BMI does not identify those with greater stores of visceral fat. A minor limitation was that height and weight were self-reported and given that we know self-reported heights and weight tend to make people taller and skinnier than they actually are (a phenomenon that one might expect to be exacerbated by age-related shrinking (there's an easy paper for someone)).Interestingly though the paper's main limitations actually supports the authors' conclusions that BMI thresholds as we currently understand them likely should not apply to the geriatric population in that either weight is in and of itself protective or that BMI cannot identify risk in the elderly though perhaps fat distribution does (another potential paper), and while the authors for some reason didn't mention it in their conclusion, this paper would certainly suggest that the most important thing a primary care physician might do when faced with an overweight or obese geriatric patient would be to constantly encourage them to be active.Leon Flicker, Kieran A. McCaul, Graeme J. Hankey, Konrad Jamrozik, Wendy J. Brown, Julie E. Byles, & Osvaldo P. Almeida (2010). Body Mass Index and Survival in Men and Women Aged 70 to 75 The Journal of the American Geriatric Society : 10.1111/j.1532-5415.2009.02677.x... Read more »

Flicker, L., McCaul, K., Hankey, G., Jamrozik, K., Brown, W., Byles, J., & Almeida, O. (2010) Body Mass Index and Survival in Men and Women Aged 70 to 75. Journal of the American Geriatrics Society, 58(2), 234-241. DOI: 10.1111/j.1532-5415.2009.02677.x

January 27, 2010
09:30 PM
580 views

Rapidly Diagnosing Lethal Blood-Based Fungal Infections

by Michael Long in Phased

Dominique Mazier (Universite Pierre et Marie Curie-Paris, France) and coworkers have used mass spectrometry to rapidly and unambiguously diagnose a blood-based fungal infection, faster than is possible through conventional diagnostics. This news feature was written on January 27, 2010.... Read more »

Marinach-Patrice, C., Fekkar, A., Atanasova, R., Gomes, J., Djamdjian, L., Brossas, J.-Y., Meyer, I., Buffet, P., Snounou, G., Datry, A.... (2010) Rapid Species Diagnosis for Invasive Candidiasis Using Mass Spectrometry. PLoS ONE, 5(1). DOI: 10.1371/journal.pone.0008862

January 27, 2010
07:00 PM
390 views

Whose demons?

by PalMD in White Coat Underground

"...It never was our guise To slight the poor, or aught humane despise: For Jove unfold our hospitable door, 'Tis Jove that sends the stranger and the poor..."---Homer: The Odyssey, Translation by Alexander PopeA few weeks ago, Drugmonkey wrote a piece about perceptions of drug users. Specifically, the study looked at how mental health providers perceive people with substance use disorders depending on whether the patients were referred to being a "substance abuser" vs. having "a substance use disorder." These data revealed something interesting. Among the mental health professionals:...those assigned the "substance abuser" term ... were significantly more in agreement with the notion that the character was personally culpable for his condition and more likely to agree that punitive measures be taken...[...][they were more likely]...to convey internal causal attribution and personal culpability, a moral vs. medical solution, suggesting the character has volitional control and might be viewed as a "perpetrator"who is willfully engaging in the behavior and thus more deserving of punishment.... Read more »

Kelly, J., & Westerhoff, C. (2009) Does it matter how we refer to individuals with substance-related conditions? A randomized study of two commonly used terms☆. International Journal of Drug Policy. DOI: 10.1016/j.drugpo.2009.10.010

Baldacchino A, Gilchrist G, Fleming R, & Bannister J. (2009) Guilty until proven innocent: A qualitative study of the management of chronic non-cancer pain among patients with a history of substance abuse. Addictive behaviors. PMID: 19897313

Health

January 27, 2010
05:11 PM
798 views

Dysbiosis - What Have We Learned?

by Michael Ash in Nutri-Link Ltd - Clinical Education

Michael Ash BSc(Hons) DO, ND, FDipION reviews some of the last 12 months of published research.

The human body has some 10 trillion human cells—but 10 times that number of microbial cells. So what happens when such an important part of our bodies goes missing or never develops?

Plus what can we do to limit any adverse consequences linked to microbial disruption – referred to as dysbiosis?... Read more »

Sartor, R. (2008) Therapeutic correction of bacterial dysbiosis discovered by molecular techniques. Proceedings of the National Academy of Sciences, 105(43), 16413-16414. DOI: 10.1073/pnas.0809363105

Martin FP, Sprenger N, Yap IK, Wang Y, Bibiloni R, Rochat F, Rezzi S, Cherbut C, Kochhar S, Lindon JC.... (2009) Panorganismal gut microbiome-host metabolic crosstalk. Journal of proteome research, 8(4), 2090-105. PMID: 19281268

Ley RE, Lozupone CA, Hamady M, Knight R, & Gordon JI. (2008) Worlds within worlds: evolution of the vertebrate gut microbiota. Nature reviews. Microbiology, 6(10), 776-88. PMID: 18794915

January 27, 2010
10:28 AM
877 views

Cross-talk: what it is and how it impacts cancer research

by Sally Church in Pharma Strategy Blog

A Pharma friend who regularly reads this blog attended the ASCO GI meeting last weekend and phoned me to say that cancer is indeed getting much more complex. She was also highly amused at the buzzword bingo post from the...... Read more »

Pollak, M., Schernhammer, E., & Hankinson, S. (2004) Insulin-like growth factors and neoplasia. Nature Reviews Cancer, 4(7), 505-518. DOI: 10.1038/nrc1387

January 27, 2010
09:40 AM
1,006 views

Mozart Effect: The effect of music on premature babies

by Nestor Lopez-Duran PhD in Child-Psych

Do you remember the Mozart Effect? In the 1990s a small yet very influential study showed that listening to classical music, and in particular Mozart, improved test performance in college students -thus Mozart must make you smarter! The public reacted and an entire industry was born. Parents rushed to the stores to purchase Mozart CDs so [...]... Read more »

Lubetzky, R., Mimouni, F., Dollberg, S., Reifen, R., Ashbel, G., & Mandel, D. (2009) Effect of Music by Mozart on Energy Expenditure in Growing Preterm Infants. PEDIATRICS, 125(1). DOI: 10.1542/peds.2009-0990

January 27, 2010
02:49 AM
1,665 views

Attachment Theory and Poorly Performing Doctors

by Dr Shock in Dr Shock MD PhD

The attachment theory from the sixties of the previous century is still used e.g. in psychotherapy but also in research such as shown in a recent post on:How do social relationships function online. Is attachment theory also useful in medical education, does it explain the poor performance by some doctors? After all doctors are required [...]

Related posts:Twitter, Doctors, Hospitals and Medical Education Beginning March 2009 the number of hospitals on using...
Is 360-degree feedback for doctors usefull or not? During residency new doctors are faced with several assessments....
Twitter during Lectures Lectures have become out of favor with medical students...

Related posts brought to you by Yet Another Related Posts Plugin.... Read more »

Adshead, G. (2010) Becoming a caregiver: attachment theory and poorly performing doctors. Medical Education, 44(2), 125-131. DOI: 10.1111/j.1365-2923.2009.03556.x

January 26, 2010
05:13 PM
489 views

Be religious and live forever!

by Tom Rees in Epiphenom

OK, so the headline's a touch optimistic. Sadly we are all going to die some day, believers and non-believers alike. But, if you have the right kind of beliefs about god, you might at least be able to persuade yourself that you're not going to die.And those beliefs are? Fatalistic ones. In a survey of some 300 elderly Philadelphians, Laraine Winter and colleagues found that a high level of deference to God's will were linked to preferences for heroic medical interventions in hopeless cases.So, for example, people who believe that God is their guide and mentor were more likely to say they would like medical intervention if they had a stroke or were in a coma with no chance of recovery, or were suffering from painful liver cancer.Now, there was some similar research last year, but what this new study adds is the confirmation that it's deference to God's will that is the important factor. These people believe that their God will save them from death by some miracle.And as was pointed out last year, this can cause some problems - one of which is a lack of planning for your death. I've dug up some more interesting research which sheds some more light on what is going on here.This research (from Amy Al and colleagues at Washington University) found that people who report experiencing "religious reverence" are, as you might expect given the above, less likely to make plans for settling their affairs after they die.However, people who had experienced reverence in a naturalistic setting (feeling reverent in the presence of nature, or enjoying music or art) were more likely to plan for their deaths.In other words, seeing beauty in the here and now allows you to be more acceptant of your inevitable death. Seeing beauty in god obstructs that.Winter L, Dennis MP, & Parker B (2009). Preferences for life-prolonging medical treatments and deference to the will of god. Journal of religion and health, 48 (4), 418-30 PMID: 19890718Ai AL, Park CL, & Shearer M (2008). Spiritual and religious involvement relate to end-of-life decision-making in patients undergoing coronary bypass graft surgery. International journal of psychiatry in medicine, 38 (1), 113-32 PMID: 18624023 This article by Tom Rees was first published on Epiphenom. It is licensed under Creative Commons.

... Read more »

Winter L, Dennis MP, & Parker B. (2009) Preferences for life-prolonging medical treatments and deference to the will of god. Journal of religion and health, 48(4), 418-30. PMID: 19890718

Ai AL, Park CL, & Shearer M. (2008) Spiritual and religious involvement relate to end-of-life decision-making in patients undergoing coronary bypass graft surgery. International journal of psychiatry in medicine, 38(1), 113-32. PMID: 18624023

January 26, 2010
03:00 PM
404 views

The Mozart Effect Revisited

by Allison in Dormivigilia

Preterm infants who listened to Mozart or other Western classical music had improved weight gain. ... Read more »

Lubetzky, R., Mimouni, F., Dollberg, S., Reifen, R., Ashbel, G., & Mandel, D. (2009) Effect of Music by Mozart on Energy Expenditure in Growing Preterm Infants. PEDIATRICS, 125(1). DOI: 10.1542/peds.2009-0990

January 26, 2010
01:40 PM
1,000 views

Cancer biology is becoming very complex #AACR

by Sally Church in Pharma Strategy Blog

As we learn more about the biology of cancer, I'm finding that rather becoming simpler, it actually seems much more complex and sophisticated than we may have first realised. Sometimes, we don't know what we don't know. Take for example,...... Read more »

Pàez-Ribes, M., Allen, E., Hudock, J., Takeda, T., Okuyama, H., Viñals, F., Inoue, M., Bergers, G., Hanahan, D., & Casanovas, O. (2009) Antiangiogenic Therapy Elicits Malignant Progression of Tumors to Increased Local Invasion and Distant Metastasis. Cancer Cell, 15(3), 220-231. DOI: 10.1016/j.ccr.2009.01.027

Ebos, J., Lee, C., Cruz-Munoz, W., Bjarnason, G., Christensen, J., & Kerbel, R. (2009) Accelerated Metastasis after Short-Term Treatment with a Potent Inhibitor of Tumor Angiogenesis. Cancer Cell, 15(3), 232-239. DOI: 10.1016/j.ccr.2009.01.021

Loges, S., Mazzone, M., Hohensinner, P., & Carmeliet, P. (2009) Silencing or Fueling Metastasis with VEGF Inhibitors: Antiangiogenesis Revisited. Cancer Cell, 15(3), 167-170. DOI: 10.1016/j.ccr.2009.02.007

Ebos, J., Lee, C., Christensen, J., Mutsaers, A., & Kerbel, R. (2007) Multiple circulating proangiogenic factors induced by sunitinib malate are tumor-independent and correlate with antitumor efficacy. Proceedings of the National Academy of Sciences, 104(43), 17069-17074. DOI: 10.1073/pnas.0708148104

Burstein, H., Elias, A., Rugo, H., Cobleigh, M., Wolff, A., Eisenberg, P., Lehman, M., Adams, B., Bello, C., DePrimo, S.... (2008) Phase II Study of Sunitinib Malate, an Oral Multitargeted Tyrosine Kinase Inhibitor, in Patients With Metastatic Breast Cancer Previously Treated With an Anthracycline and a Taxane. Journal of Clinical Oncology, 26(11), 1810-1816. DOI: 10.1200/JCO.2007.14.5375

Ebos JM, Lee CR, Cruz-Munoz W, Bjarnason GA, Christensen JG, & Kerbel RS. (2009) Accelerated metastasis after short-term treatment with a potent inhibitor of tumor angiogenesis. Cancer cell, 15(3), 232-9. PMID: 19249681

January 26, 2010
12:32 PM
966 views

Cool paper, & winner of "worst new omics word award": Predatosome

by Jonathan Eisen in The Tree of Life

And the bad new omics words keep streaming in. Today's winner of the "Worst New Omics Word Award" is going to Carey Lambert, Chien-Yi Chang, Michael J. Capeness and R. Elizabeth Sockett from Nottingham for their use/ invention of "Predatosome". They use this term in the title of their new PLoS One paper: The First Bite— Profiling the Predatosome in the Bacterial Pathogen Bdellovibrio. Here is the very long sentence where the define it:The gene products required for the initial invasive predatory processes have not been extensively studied but the genome sequencing of B. bacteriovorus HD100 [1] revealed a genome of 3.85Mb, including a core genome similar to that of non-predatory bacteria and some 40% of the genome comprising a potential predicted “predatosome” of genes, encoding both hydrolytic products that may be employed in prey degradation, and genes that may be required specifically for host predation and thus are not conserved across the Proteobacteria.The paper is actually quite interesting. They use genomic approaches to characterize a fascinating organism - the bacterial species Bdellovibrio bacteriovorus. This bug is a predatory organism - eating other bacteria. Since it eats them from the inside out, some, including these authors, refer to this organism as a pathogen of other bacteria and their is some discussion here and elsewhere for its potential to serve as a "living antibiotic" in much the same way people are trying to use bacterial viruses (a.k.a. phage).The paper overall is quite nice on first read. They used microarray studies to characterize gene expression patterns in different phases of the life cycle (see Figure above for the life cycle outline). They backed up this work by quantitative PCR studies and regular RT PCR. And based upon their analysis they found some genes that are "Up-Regulated in Predatory, but Not HI" phase (HI stands for host-independent). And here is where they really tell us what they mean by predatosome:This category of 240 genes are very interesting as they potentially exclude those genes simply involved with release from attack-phase into growth, namely they should be part of the “predatosome” of predatorily specific genes.It seems to me this terminology is completely unnecessary. All they need to do is say they are studying the genes related to the predatory phase. To assign these genes to the "predatosome" is a bit much. They continue in the paper to report some really interesting stuff. For example, they also examine another predatory bacterial species, and look at whether there are genes conserved in the process between species. They made some really nice figures by the way about the different phases of hte life cycle in this organism and which genes are expressed:Anyway - the science in the paper is nice. However, the invention of yet another omics word is a bit much. And thus Lambert et al. are winners of the highly coveted "Worst New Omics Word Award" for their invention of "predatosome". Details on the paper are below - and that is where the figures come from too. (Hat tip to Bora for letting me know about the paper, and the word).Lambert, C., Chang, C., Capeness, M., & Sockett, R. (2010). The First Bite— Profiling the Predatosome in the Bacterial Pathogen Bdellovibrio PLoS ONE, 5 (1) DOI: 10.1371/journal.pone.0008599Friendfeed comments below:
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This is from the "Tree of Life Blog"
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Lambert, C., Chang, C., Capeness, M., & Sockett, R. (2010) The First Bite— Profiling the Predatosome in the Bacterial Pathogen Bdellovibrio. PLoS ONE, 5(1). DOI: 10.1371/journal.pone.0008599

January 25, 2010
08:32 AM
819 views

How we discovered that an attention drug successfully treats a fruit fly memory mutant

by Björn Brembs in bjoern.brembs.blog

Blogging about one's own research always feels good: the amount of your work has accumulated enough to at least provide sufficient material for a story and some figures. It has passed the first hurdle of scientific scrutiny, peer review. On the other hand, now an exciting time begins: what will the colleagues say? Will people find the one major flaw that neither you, your co-authors, the people who proof-read the drafts before submission nor the reviewers caught? Will the results lead to new, exciting collaborations, will it be cited or will it just be met with utter apathy and complete indifference? After all, with about 1.5 million scholarly publications in approx. 24.000 journals, it's not at all unlikely that your paper just simply never is found by anyone who might be interested in it.All this of course applies to our latest paper as well. However, for those who do read it, I'm sure it will be a fascinating read. It is, without exaggeration, the craziest scientific story I've ever been involved in, an example of serendipity in science if ever there was one. Here's how it all happened. Shortly after we published our mathematical analysis of spontaneous turning behavior in stationary flying Drosophila, Bruno van Swinderen contacted me about a collaboration. I knew Bruno from before (see here and here), but we had never worked together on a project. So I was very excited to hear that he wanted me to test some of his flies in the Drosophila flight simulator, using the exact same techniques we just had published. The initial idea was to use these mathematical analyses to test his mutant flies for any abnormalities in their spontaneous behavior. However, it turned out that the mutant flies that he had sent me, radish, didn't really fly all that well, at least not well enough to generate enough data to run our mathematics on them. Neither did Bruno tell me about his results, we wanted that I should be blind as to the deficits he had found in radish. I knew radish was a memory mutant for olfactory conditioning, but that it could learn visual patterns just fine. Beyond that, nobody knew what other behavioral phenotypes this strain would exhibit.So I went on to test a whole bunch of other things for which I had the experimental setups readily available. Of all these experiments, I picked the simplest one and sent Bruno the raw data back. I just measured the flies' spontaneous turning attempts without any visual stimulation for as long as I could get the flies to fly continuously, which was six minutes. As a control experiment, the flies' behavior was measured in a flight simulator-like situation, where they could control their flight direction with respect to four visual landmarks (but still tethered, of course). I sent Bruno the data in blind, which means he didn't know which group was the wildtype control and which was the mutant group. He immediately wrote back accurately identifying the mutant group. I had no idea how he could have figured out which group was which so quickly and the experiments were basically concluded, so he started to show me his data. Bruno does something very few people on this planet are doing: he can put tiny little electrodes in the flies' brains and record their brain waves. Now with this particular mutant strain, he found that they had a peak in the power spectrum of their brain waves at around 1.6 Hz. Stunningly, when he computed the power spectrum of their turning behavior (i.e., my data), he also found a peak at about 1.6 Hz, but only when the flies were flying with the four visual landmarks. The peak was much less pronounced when there were no explicit stimuli in their environment. It was by this peak that he had recognized the mutants so quickly. But what could this peak mean? One thing it could mean is that the mutant flies become fidgety, if there's something in the environment they need to pay attention to. About one and a half times per second, the flies are initiating some turning maneuver, which can be seen as a peak in the power spectrum. In other words, the flies are hyperactive or fidgety, in this very well-defined, oscillatory kind of way. He then went on to tell me that they also were more easily distractable than the wildtype controls, both in behavior and by inferring from their brain waves when presenting them with various competing visual stimuli.I thought this was really quite amazing. Flies which are known for their memory loss are both hyperactive and have an attention deficit. I immediately thought of people with attention deficit / hyperactivity disorder (ADHD). They also have learning problems. As a joke, I suggested we put the flies on Ritalin, the drug used to treat patients with ADHD. Bruno replied that these data were actually intended for a different publication, but they indeed would fit very well with this one, too. I was flabbergasted! He had already done the experiments with methylphenidate (Ritalin is just the trade name). To my utter astonishment, the flies on methylphenidate performed like their wildtype counterparts in almost all of the tests we subjected them to. This is even more amazing when you consider that the mutated gene, radish, is required during brain development (late during pupation) and not during the behavioral test. In other words, methylphenidate rescues a deficit in adulthood that even a healthy copy of the originally mutated gene cannot rescue any more. I find it absolutely crazy to find a fly model for a human psychiatric disorder. On top of that, Ritalin, the drug used to treat ADHD in humans actually also successfully treated the flies. It's even more crazy to find all that by accident, without even looking for it! All we wanted was to study some interesting fly mutants to learn more about some basic brain function. How can it be possible to find something like this just by serendipity? My favorite hypothesis is that there are some fundamental principles about how all brains work and we have stumbled across one of them. We still don't know what it is or how it works, only that it has to do with how brain allocate attention to different processing streams. It is tempting to speculate that this process has to do with switching of activity between separate networks, but there currently is no data to tell either way.I do have plenty of other interesting results from this mutant, both in flight and in walking. However, I cannot make much sense of them, yet, so a lot of further research is required before part two of this story can be presented.Of course, as usual, I have a copy of the paper, together with all the supplementary material, on the download page.van Swinderen, B., & Brembs, B. (2010). Attention-Like Deficit and Hyperactivity in a Drosophila Memory Mutant Journal of Neuroscience, 30 (3), 1003-1014 DOI: 10.1523/JNEUROSCI.4516-09.2010... Read more »

van Swinderen, B., & Brembs, B. (2010) Attention-Like Deficit and Hyperactivity in a Drosophila Memory Mutant. Journal of Neuroscience, 30(3), 1003-1014. DOI: 10.1523/JNEUROSCI.4516-09.2010

January 24, 2010
04:48 PM
398 views

Cavemen, Clinique, and Chanel No. 5

by Allison in Dormivigilia

Scientists uncovered perforated Pecten shells containing red-to-black pigments suggesting that Neanderthals were equally as materialistic... Read more »

Zilhao, J., Angelucci, D., Badal-Garcia, E., d'Errico, F., Daniel, F., Dayet, L., Douka, K., Higham, T., Martinez-Sanchez, M., Montes-Bernardez, R.... (2010) Symbolic use of marine shells and mineral pigments by Iberian Neandertals. Proceedings of the National Academy of Sciences, 107(3), 1023-1028. DOI: 10.1073/pnas.0914088107

January 24, 2010
03:28 PM
662 views

A "Severe" Warning for Psychiatry

by Neuroskeptic in Neuroskeptic

Imagine there was a nasty disease that affected 1 in 100 people. And imagine that someone invented a drug which treated it reasonably well. Good work, surely.Now imagine that, for some reason, people decided that 10% of the population need to be taking this drug, instead of 1%. So sales of the drug sky-rocket. Eventually some clever person comes along and asks "This is one of the biggest selling drugs in the world - but does it work?" They look into it, and find that it doesn't work very well at all. For about 9 out of 10 people, it's completely useless! What a crap drug.*Back to reality. According to accepted DSM-IV diagnostic criteria, close to 50% of people suffer from a mental illness at some point; a large fraction of this being depression. 10% of Americans took antidepressants last year according to the best estimates.Guess what? Clever people have started asking "Antidepressants are amongst the biggest selling drugs in the world - but do they work?" And the answer is - not very well. The latest such claim came from Fournier et al and appeared in JAMA a couple of weeks ago: Antidepressant Drug Effects and Depression Severity.These researchers re-analysed the data from six clinical trials testing antidepressants against placebo pills. The drugs were the tricyclic imipramine and the newer SSRI paroxetine. The total sample size was a respectable 718, and most trials lasted 8 weeks, which is longer than average for this kind of study. Here's what they found -Grey circles are people on antidepressants, white circles people on placebo. What this shows is that the more severe the patient's depression, the more they get better - when they're given either drugs or placebos. However, because the improvement on antidepressants rises more steeply, the benefit of antidepressants versus placebos correlates with severity. The thin blue line marks the minimum severity for which the average effect of the drugs over placebo was "clinically significant" according to NICE criteria.*So, this study says that antidepressants work better in more severe depression. This is not a new claim - Kirsch et al (2008) famously found the same thing, and long before that so did Khan et al (2002). However this new analysis has some advantages over previous ones. First, Fournier et al looked at what happened to each patient individually, whereas the previous studies found that in trials where the patients were more severely depressed, on average, antidepressants worked better.Second, the patients in this analysis spanned a wide range of severity scores, from 10 points on the Hamilton Scale to nearly 40. In Kirsch et al almost all the trials had average severities in the narrow range of 22 to 29. Finally, none of the trials in the new paper used a placebo washout period. These are meant to exclude people from the trial if they improve "too well" during an initial week or so of placebo pills. In theory, they bias trials against finding large placebo effects; it's not clear they actually work, but either way, it's good to know it wasn't a factor.*Overall, the evidence all seems to point to the idea that people with more serious clinical depression respond better to antidepressants vs. placebos in clinical trials. The exact details are debatable, there's the issue of whether antidepressant clinical trials are realistic, and the question of how clinically effective antidepressants are is also controversial, but I'm not aware of any studies which have contradicted this central claim.But when you start to think about, this is a very odd result. Fournier et al say thatThe general pattern of results reported in this work is not surprising. As early as the 1950s, researchers conducting controlled investigations of treatments for a wide variety of medical and psychiatric conditions described a phenomenon whereby patients with higher levels of severity showed greater differential (i.e., specific) benefit from the active treatments.and refer to a couple of papers from the 1960s. But I must admit that I do find this very surprising. We don't wait until someone's nearly dead from a bacterial infection before we give them antibiotics, we give them early, when the disease is still mild. Doctors unfortunately don't tell people "Good news! You've got advanced-stage cancer - just the kind where drugs work best." Why is depression so different?Look a little closer, and a possible answer emerges. Severity, in all of these studies, was measured using the Hamilton Rating Scale for Depression (HAMD). The HAMD has 17 items, and each asks whether you're suffering from certain symptoms; the more symptoms you have, and the more pronounced they are, the higher your total score. You get 1 point if you have "occasional difficulty falling asleep", 2 points for "nightly difficulty falling asleep", 4 points for "Hand wringing, nail biting, hair-pulling, biting of lips". Here's the whole thing.The HAMD was designed in 1960 by a psychiatrist, Max Hamilton, and it was originally intended for use by staff at psychiatric hospitals for use on depressed inpatients. So it's not a measure of severity per se: it's a measure of how well your symptoms match those considered to be characteristic of severe depression in 1960.Western psychiatry's concept of depression has changed greatly since then; for one thing, this was 20 years before the DSM-III criteria of depression were published, which form the basis for today's DSM-IV criteria. A quick comparison of the DSM-IV alongside the HAMD reveals a lot of differences. It's quite possible to meet DSM-IV criteria for "Major Depressive Disorder" yet score low on the HAMD.Which brings us back to the imaginary scenario at the start of this post. My personal interpretation of results like those of Fournier et al is this: antidepressants treat classical clinical depression, of the kind that psychiatrists in 1960 would have recognized. This is the kind of depression that they were originally used for, after all, because the first antidepressants arrived in 1953.Yet in recent years "clinical depression" has become a much broader term. Many people attribute this to marketing on the part of pharmaceutical companies. Whatever the cause, it's almost certain that many people are now being prescribed antidepressants for emotional and personal issues which wouldn't have been considered medical illnesses until quite recently. Antidepressants also ha... Read more »

Fournier, J., DeRubeis, R., Hollon, S., Dimidjian, S., Amsterdam, J., Shelton, R., & Fawcett, J. (2010) Antidepressant Drug Effects and Depression Severity: A Patient-Level Meta-analysis. JAMA: The Journal of the American Medical Association, 303(1), 47-53. DOI: 10.1001/jama.2009.1943

January 24, 2010
01:16 PM
710 views

HIIT (on bikes) - why it results in both more fat reduction, and Spot Fat Reduction at That, too than Hearty Steady State

by mc in begin to dig (b2d)

HIIT means high intensity interval protocol. But what is the best HIIT to do if you're tuning it for fat lost first, and anything else second? And does it make a difference if you're dealing with elite athletes or people who are just well enough conditioned so their hearts won't explode if you ask them to go "really hard" for a bit? Is it 60 secs on? 30 off? 60:60? The infamous tabatta on for 20 off for 10 - and remember that was not primarily a fat burning study but an anaerobic/aerobic capacity study.... Read more »

Trapp, E., Chisholm, D., Freund, J., & Boutcher, S. (2008) The effects of high-intensity intermittent exercise training on fat loss and fasting insulin levels of young women. International Journal of Obesity, 32(4), 684-691. DOI: 10.1038/sj.ijo.0803781

GORMLEY, S., SWAIN, D., HIGH, R., SPINA, R., DOWLING, E., KOTIPALLI, U., & GANDRAKOTA, R. (2008) Effect of Intensity of Aerobic Training on V??O2max. Medicine , 40(7), 1336-1343. DOI: 10.1249/MSS.0b013e31816c4839

Trapp, E., Chisholm, D., & Boutcher, S. (2007) Metabolic response of trained and untrained women during high-intensity intermittent cycle exercise. AJP: Regulatory, Integrative and Comparative Physiology, 293(6). DOI: 10.1152/ajpregu.00780.2006

January 24, 2010
05:00 AM
124 views

What Love and Attraction Smells Of

by Linda in Oz Blog No. 159

I'd read (somewhere) that bouquets of chemicals you release when you meet 'that someone' become a concoction for hell that loving feeling. (Somewhat reminds me of that wacky Sandra Bullock film Love Potion No. 9). For the first 6 months-year you release endorphins, adrenaline, oxytocin. Subsequently, you might get 'butterflies', the sweats, sleepless nights, loss of appetite etc. etc. What causes that initial attraction anyways? i find it so random. If it was just personality, then in theory I should be attracted to many of my male friends (aieeeee). ... Read more »

Wedekind C, Seebeck T, Bettens F, & Paepke AJ. (1995) MHC-dependent mate preferences in humans. Proceedings. Biological sciences / The Royal Society, 260(1359), 245-9. PMID: 7630893

Bernatchez L, & Landry C. (2003) MHC studies in nonmodel vertebrates: what have we learned about natural selection in 15 years?. Journal of evolutionary biology, 16(3), 363-77. PMID: 14635837

SANDROCARVALHOSANTOS, P., AUGUSTOSCHINEMANN, J., GABARDO, J., & DAGRACABICALHO, M. (2005) New evidence that the MHC influences odor perception in humans: a study with 58 Southern Brazilian students. Hormones and Behavior, 47(4), 384-388. DOI: 10.1016/j.yhbeh.2004.11.005

Lie, H., Simmons, L., & Rhodes, G. (2010) Genetic dissimilarity, genetic diversity, and mate preferences in humans. Evolution and Human Behavior, 31(1), 48-58. DOI: 10.1016/j.evolhumbehav.2009.07.001

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