Day: 06/18/2014

Gaia grapples with stray light

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The orbiting Gaia telescope will lose some performance because stray light is getting inside the observatory, the European Space Agency (Esa) says.

Gaia optical payload

But the impacts are likely to be very small, scientists believe, and the expectation is that all the mission’s chief objectives will still be met.

Most of the unwanted light appears to be creeping around the giant shield Gaia uses to shade itself from the Sun.

The “pollution” makes it harder for the observatory to see the faintest stars.

“I must say this is not a major problem,” said Esa’s Gaia project manager, Giuseppe Sarri.

“The point is the spacecraft is doing very well in terms of everything is working, and now we’re focussing on the things we want to improve.

“We were expecting to get some stray light but the fact is, it is larger than we predicted,” he told BBC News.

Gaia was sent into orbit in December to do astrometry on a billion stars – to map their precise positions, distances and motions.

Telescope tent

This huge sample should provide the first true picture of our Milky Way Galaxy’s structure.

As is normal after launch, the observatory was immediately put through a period of complex systems check-out and instrument calibration.

Engineers noticed early on that unexpected light was getting inside the big tent covering the satellite’s dual telescope mechanism.

Modelling indicates most of it is sunlight being diffracted around the observatory’s 10.5m-wide sunshield.

But further analysis suggests there is likely also some additional component – probably the general diffuse light on the sky itself.

GAIA – THE DISCOVERY MACHINE

Gaia (Esa)
  • The Gaia mission will make a very precise 3D map of our Milky Way galaxy
  • It is Europe’s successor to the Hipparcos satellite which mapped some 100,000 stars
  • The one billion to be catalogued by Gaia is still only 1% of the Milky Way’s total
  • But the quality of the new survey promises a raft of discoveries beyond just the stars themselves
  • Gaia will find new asteroids, failed stars, and allow tests of physical constants and theories
  • Its map of the sky will be a reference frame to guide the investigations of future telescopes

The effect is certainly a nuisance because it makes it more difficult for Gaia to discern the least bright objects.

It was the mission’s aim to measure the positions of all stars down to magnitude 20 (about 400,000 times fainter than can be seen with the naked eye).

The stray light means about 40% of the accuracy of those measurements at this lowest magnitude will be lost.

Backwards and forwards

On the upside, it should be possible to get some of the performance back if Esa agrees to extend the mission and additional data can be taken.

And it is true to say that most of Gaia’s science will be done at magnitude 15 (4,000 times fainter than the naked eye limit) and brighter, which is unaffected.

Where the pollution issue may be felt more keenly is in determining the motions of stars towards or away (radial velocity) from the satellite.

This information will have a number of applications but will be used to help make a 3D movie of the galaxy – to run forwards to see what happens millions of years into the future, and backwards to reveal how the galaxy was assembled in the deep past.

Gaia was hoping to get radial velocity data for about 150 million of the brightest stars.

It involves taking the light from a star and spreading it out into its component colours for analysis. For the faintest objects in the targeted sub-set of stars, this process again becomes much harder with stray light.

“Start Quote

There’s no reason to believe Gaia won’t be a triumph”

Prof Gerry Gilmore Cambridge University

The Gaia team thinks with some smart techniques it can recover some of the performance loss, but as it stands the mission may get radial velocity measurements now on only about 100 million stars.

“We say only about 100 million stars – that’s still pretty spectacular,” said Prof Gerry Gilmore, a Gaia scientist from the Institute of Astronomy at Cambridge University, UK.

“We don’t actually know how many stars there are in the sky at the magnitudes needed to do the radial velocity measurements,” he added.

“We had a guess that it was 150 million but that could be wrong by a factor of two; so it’s quite possible there are a lot more stars out there [we can still measure].

“Gaia is the first ever high spatial resolution survey and so until Gaia has scanned the sky we won’t know what’s on the sky.”

Gaia optical payload Large sections of Gaia’s telescope mechanism were constructed out of silicon carbide

Engineers are also tracking an issue with what they call the “basic angle”.

Part of Gaia’s measurement strategy requires it to look at two parts of the sky at the same time to lock a frame of reference.

This is why it carries two telescopes held rigidly at an offset angle of 106.5 degrees. Great effort was put into making sure this basic angle was absolutely stable, with many components being constructed out of stiff silicon carbide as a consequence.

Exploring our galaxy

Telescope

How do telescopes let us see so far into space?

But a vanishingly small flexure is being detected – fractionally beyond what had been anticipated.

The team believes, though, it can nullify any impacts if the behaviour can be properly characterised.

“It’s all nuisance stuff. Depending how you count it, there are about 500 critical components on Gaia and they’re all working fine,” said Prof Gilmore.

“Yes, it’s complicated; yes, there are things we don’t fully understand yet; but there’s no reason to believe Gaia won’t be a triumph.”

Mr Sarri added that after the long commissioning process, the telescope was now ready to gather data continuously.

“In the last week, we had an informal handover and it’s been working already in science mode on occasions. But now we will move into a period of 28 days of uninterrupted operation,” he told BBC News.

Researchers Focus on Recovery in Schizophrenia Medical News & Perspectives

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The outlook for people diagnosed with schizophrenia, once considered a devastating illness that only worsens over time, has improved in the past several decades. Antipsychotic medications and psychosocial treatments have allowed many with the illness to achieve some degree of recovery, manage residual symptoms, and lead productive lives. Yet additional efforts are needed to consolidate these improvements and help more patients reach these goals.

“For many years we’ve underestimated the ability of people with schizophrenia to change and improve their lives, and in fact, clinical care in many settings actually constrains patients and creates lower expectations about what they can achieve,” said Stephen Marder, MD, professor of psychiatry at the University of California, Los Angeles. Now, however, modern approaches to managing the disorder can help patients attain more normal function, he said.

These approaches are outlined in a new report, “Schizophrenia: Time to Commit to Policy Change,” drafted by Marder and others (Fleischhacker WW et al. SchizophreniaBull. 2014;40[3]:S165-S194). Their policy recommendations include providing the following:

  • Evidence-based, integrated care packages for people with schizophrenia that address their physical and mental health needs

  • Support for people with schizophrenia to help them enter and remain in their communities and to find and retain employment

  • Support and education for family members and caregivers

  • Funding for research and development of new treatments

Marder was among several experts who spoke about issues of recovery in schizophrenia at the annual American Psychiatric Association meeting held here in May.

COPING SUCCESSFULLY WITH SCHIZOPHRENIA

Some individuals with schizophrenia have learned to manage their symptoms and live productive lives, developing their own paths to “recovery” from severe mental illness, and their stories are helping to strengthen understanding of what it means to accomplish this, said Marder.

“There are far more people with schizophrenia who are working and going to school than who are living on the street homeless, and to change perceptions, we have to use those faces rather than the faces that many of us imagine,” said Marder.

Some individuals with schizophrenia have learned to manage their symptoms and live productive lives, developing their own paths to “recovery” from severe mental illness.

Several years ago, Marder and his colleagues set out to study the characteristics of people with schizophrenia who were considered occupationally high achieving and to discover the strategies these individuals used to reach their current level of functioning and to negotiate their daily lives.

The study included 10 men and 10 women with high-functioning schizophrenia who successfully coped with active psychotic symptoms, such as mild delusions or hallucinatory behavior. Their average age was 40 years. All had at least a high school diploma, several had professional jobs, others held technical or managerial jobs, and a few were pursuing graduate studies.

Through intensive interviews examining each individual’s life history, the researchers identified common compensatory mechanisms that these people used to deal with their illness. Their strategies included taking medications as prescribed, staying physically healthy and getting enough exercise, controlling the amount of stimulation in their environment, and being involved in the mental health recovery movement. The importance of meaningful work and friendship were also common themes that emerged from the interviews.

“Although these individuals are high functioning, their lives aren’t easy,” emphasized Marder. Nevertheless, they’ve learned to cope with their symptoms and have been able to live full lives, reminding clinicians that an optimistic outcome in schizophrenia is possible, he said.

THE CONCEPT OF RECOVERY

What constitutes recovery from a psychiatric condition is a matter of ongoing debate, said Lisa Halpern, MPP, director of recovery services at Vinfen, a nonprofit organization in Cambridge, Massachusetts, that provides psychiatric and other support services to adults and children with mental illness.

The concept of recovery in schizophrenia has evolved from a focus on the total cessation of symptoms to an emphasis on the potential for growth despite the presence of mental illness, said Halpern. Recovery does not mean cure, but rather a process that involves learning to live with and manage the disorder—being “in recovery.”

Halpern herself has learned to cope with schizophrenia, having been diagnosed with the disorder as a graduate student at Harvard University. She noted that medical therapy—in her case, the antipsychotic medication clozapine—helped with her positive symptoms of hallucinations and delusions, but it was not as helpful with her cognitive and negative symptoms, which included loss of the ability to read or write. For these symptoms, rehabilitative therapy—brain training beginning with preschool books and coloring books and working up to Shakespeare—was effective.

This combination of medical and rehabilitative models of care helped Halpern return to graduate school and attain her degree. Her recovery, she said, depended on both approaches used in complementary fashion: medication and clinical interventions for positive symptoms and rehabilitation for negative and cognitive symptoms.

Recovery is a profoundly social process, said Halpern. She cited integration into the community as one important component. In the 2003 final report from the President’s New Freedom Commission on Mental Health (http://bit.ly/1ujrLBU), which presented a strategy for transforming mental health care, the definition of recovery is “the process through which people are able to live, work, learn, and participate fully in their community.”

Similarly, peer support is another important factor that influences recovery, said Halpern. Support from individuals with life experience of schizophrenia can provide opportunities for coaching, mentoring, and guidance with coping and advocacy (Duckworth K and Halpern L. Curr Opin Psych. 2014;27[3]:216-221).

Support for family members is also integral to the recovery process, said Kenneth Duckworth, MD, medical director of the National Alliance on Mental Illness (NAMI) and assistant professor at Harvard University Medical School, Cambridge. NAMI’s Family-to-Family Education Program, a 12-week course for family members of adults with mental illness, has been shown in a randomized controlled trial to enhance family members’ coping skills (Dixon LB et al. Psychiatr Serv. 2011;62[6]:591-597).

Duckworth noted that while many psychosocial therapies for schizophrenia can promote recovery, reduce hospitalizations, and increase employment rates, the extent to which they are funded by health care systems varies, and as a result, many patients are unable to access such treatment. Addressing that situation is crucial, he says.

Premature mortality among people with schizophrenia—who die 15 to 20 years earlier than others—is also untenable, said Duckworth. “The literature shows that people with schizophrenia tend not to receive adequate monitoring or good care for cardiovascular risk factors,” said Duckworth. “At NAMI, we’re trying to figure out through our peer-to-peer and family-to-family work how to raise awareness about improving the health of people with this disorder by improving monitoring for premature cardiovascular disease outcomes.”

Another key component to increasing functional recovery in schizophrenia is to intervene as early in the course of illness as possible. Recent research suggests that the earlier an intervention is begun to prevent or minimize the brain changes involved in schizophrenia, the more likely it will be to limit the severity of the illness. Intervening even before a psychotic episode occurs in people who are experiencing prepsychotic symptoms such as weak hallucinations and paranoia but not full-on psychosis is an approach favored by some investigators.

A number of small, randomized controlled trials examining different interventions, such as low doses of antipsychotics, cognitive behavioral therapy (CBT), and omega-3 fatty acids, have been carried out among people at risk for developing psychosis.

Although antipsychotics have shown some benefit in preventing or slowing the rate of psychotic transition, concerns about the risks of weight gain and metabolic problems in adolescents have discouraged clinicians from using them to treat attenuated psychosis or early-onset schizophrenia (Sikich L et al. Am J Psychiatry. 2008;165[11]:1420-1431).

Other treatments such as CBT have fewer adverse effects and are better tolerated than medications. In a study of 201 people at risk, the number of transitions to psychosis were reduced by about 50% with a CBT intervention targeting cognitive biases; that is, for developing psychosis, CBT reduced the number of transitions to psychosis by 50% (van der Gaag M et al. Schizophr Bull. 2012;38[6]:1180-1188). And a study with omega-3 fatty acids also has shown evidence of reducing the risk of progression to psychotic disorder in individuals at high risk for psychosis (Amminger GP et al. Arch Gen Psychiatry. 2010;67[2]:146-154).

Another alternative to antipsychotic medication is to target the cognitive dysfunction that seems to underlie poor information processing with computerized cognitive training—an intensive, adaptive training approach that exploits intact mechanisms of repetitive practice in the schizophrenic brain, said Rachel Loewy, PhD, assistant professor at the University of California, San Francisco. She and her colleagues have been working to develop computer-based early interventions to prevent or reverse the cognitive damage of schizophrenia.

Cognitive symptoms of schizophrenia present early in the course of the disorder, and some of them worsen as psychosis develops, said Loewy. Trouble with processing incoming information impairs the ability to take in information and also undermines the accuracy of that information, she explained. “It’s like a noisy radio that isn’t quite tuned,” she said. “The information comes in as static.”

Several years ago, Loewy’s group demonstrated that patients with chronic schizophrenia who received computerized auditory training had significant gains in global cognition, verbal working memory, and verbal and learning memory, compared with the control group (Fisher M et al. Am J Psychiatry. 2009;166[7]:805-811). Six months later, many of the cognitive gains induced by the training were retained (Fisher M et al. Schizophr Bull. 2010;36[4]:869-879).

More recently, Loewy’s group has been conducting trials in 2 groups of young people, those with recent-onset schizophrenia and those at high risk for schizophrenia. In the first trial, Loewy’s group found that those who performed 40 hours of cognitive training showed improvement in global cognition, verbal memory, and problem-solving compared with control subjects who performed 40 hours of commercial computer games (Fisher M et al. Schizophr Bull. doi:10.1093/schbul/sbt232 [published online January 20, 2014]). “Not only do we see these changes, but they appear even stronger in the recent-onset patients compared to the chronic patients,” said Loewy.

The study in young people at high risk for psychosis is about halfway completed, said Loewy. Preliminary data indicate that improvements in cognitive performance similar to those seen in the other groups are occurring, but whether these effects are significant, whether they persist long after training ends, or if they actually prevent transitions to full-blown psychosis remain to be seen, she said.

Schizophrenia remains a challenging diagnosis, but research and development into new therapies and improving access to current treatments hold promise for helping more patients achieve recovery.

“There are modern approaches to the management of schizophrenia that can aim patients toward recovery and more normal function,” said Marder

How To Evaluate Cardiovascular Risk in a Patient With Erectile Dysfunction.

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Introduction

Cardiovascular disease is a leading cause of death and disability in men. Erectile dysfunction, a common problem in men as they age, may also help drive them to seek medical attention in the absence of other cardiovascular symptoms. The link between erectile dysfunction and cardiovascular disease, while now well established, has been previously characterized primarily by shared risk factors.1-4 A number of risk factors are shared by erectile dysfunction and cardiovascular disease, including age,5 sedentary lifestyle, obesity, smoking, hypercholesterolemia, metabolic syndrome,6 insulin resistance,7 hypertension,8,9 and diabetes.8 The common pathophysiologic bases for erectile dysfunction and cardiovascular disease are believed to include endothelial dysfunction,10 inflammation,11 and low testosterone.10,12 The most common organic (medical) etiology of erectile dysfunction is vasculogenic. Numerous studies in men with clinically evident cardiovascular disease have established erectile dysfunction as an independent risk marker for cardiovascular disease4,13 and shown that erectile dysfunction frequently precedes coronary artery disease,14-17 peripheral arterial disease,18 and stroke.15 Erectile dysfunction symptoms appear approximately two to five years before the onset of cardiovascular symptoms,14,19-21 and more severe erectile dysfunction has been correlated with greater atherosclerotic burden;17 extent of coronary artery disease;14,22 and risk of coronary artery disease,15,16 peripheral artery disease,18 and major cardiovascular events.23

An emerging paradigm indicates that erectile dysfunction is in fact an independent marker of cardiovascular disease risk.4 Thus, the presence of erectile dysfunction may provide the opportunity for cardiovascular disease risk mitigation in men with otherwise unrecognized cardiovascular disease. The importance of evaluating cardiovascular risk in men with erectile dysfunction is now a critical factor for overall early stage management of cardiovascular disease, especially in younger men (aged 30 – 60 years). This brief article focuses on the evaluation of cardiovascular risk in men with erectile dysfunction but no known cardiovascular disease.

Recommendations for Evaluation of CV Risk in Men With Erectile Dysfunction but No Known CVD

Erectile dysfunction is now a well-established, independent marker for cardiovascular disease risk,4 and all men should be questioned about their sexual history and functioning as part of the initial assessment of cardiovascular disease risk. Initial inquiry for erectile dysfunction can be done by asking a simple question such as “Have you noticed any change over the past month in your ability to get or maintain a rigid erection suitable for satisfactory intercourse?” Another option is to use a short scored validated questionnaire such as the Brief International Index of Erectile Function (IIEF-5) to assess for erectile dysfunction severity.24 For all men with erectile dysfunction, particularly those with vasculogenic erectile dysfunction, initial risk stratification should be based on some type of cardiovascular risk score to estimate the 10-year risk for myocardial infarction or coronary death. In the past, the Framingham Risk Score25,26 or SCORE was recommended but future studies will likely utilize the 2013 Prevention Guidelines ASCVD Risk Estimator. The following may be used to identify men whose cardiovascular risk may exceed that estimated by a risk score calculator: a thorough history; physical examination (including measures of visceral adiposity); assessment of erectile dysfunction severity and duration; evaluation of fasting plasma glucose; resting electrocardiogram; serum creatinine (estimated glomerular filtration rate) and albumin:creatinine ratio; plasma lipid levels (total, low density lipoprotein, and HDJ cholesterol and triglyceride values) and presence or absence of the metabolic syndrome.26 The British Society of Sexual Medicine,27 Third International Consultation on Sexual Medicine,28 and Princeton III Consensus,26 all recommend that total testosterone levels be measured as a potential cause of erectile dysfunction, particularly in those for whom phosphodiesterase type 5 inhibitors have failed. Although there are no generally accepted lower limits of normal total testosterone, there is general agreement that total testosterone >350 ng/dL (12 nmol/L) does not usually require substitution and, based on data from young hypogonadal men, those with total testosterone <230 ng/dL (8 nmol/L) could be considered as candidates for testosterone treatment if they are symptomatic and appropriately monitored.29 Given the evidence that treatment of obstructive sleep apnea can improve erectile function,30,31 along with observational studies suggesting treatment of obstructive sleep apnea may improve cardiovascular outcomes,32,33 healthcare providers should also consider evaluating patients with erectile dysfunction for sleep apnea. Based on results of the above-mentioned clinical assessments, the provider may encourage lifestyle changes (e.g., diet, exercise, smoking cessation), which are likely to reduce cardiovascular risk and improve erectile function.34,35 Interventions to control specific cardiovascular risk factors (e.g., hypertension, diabetes, hyperlipidemia, obstructive sleep apnea) may also be appropriate. Men who appear to be at high risk for cardiovascular events should be referred to a cardiologist. Men who appear to be at intermediate-risk men with vasculogenic erectile dysfunction and no overt cardiovascular disease undergo further noninvasive evaluation of cardiovascular risk using exercise stress testing, carotid intima-media thickness or coronary artery calcium scoring. Recently, in a comparison of the ability of six risk markers (coronary artery calcium scoring, carotid intima-media thickness, ankle-brachial index, brachial flow–mediated dilation, high-sensitivity C-reactive protein, and family history of coronary heart disease) to improve prediction of incident coronary heart disease/cardiovascular disease in patients at intermediate risk (Framingham 10-year risk, >5%–<20%) enrolled in the Multi-Ethnic Study of Atherosclerosis, coronary artery calcium scoring provided superior improvements in risk estimation versus the other risk markers.36 Neither the most appropriate order of testing nor the prognostic superiority of one test over another has been established but both topics are the focus of ongoing research to determine the best approach to evaluate men with erectile dysfunction for subclinical vascular disease as part of the overall risk assessment. At this time, these tests should be selected based on clinical judgment, availability, and cost.

Conclusion

Vasculogenic erectile dysfunction should be regarded as a harbinger of silent or future cardiovascular disease. Thus, strategies that aid in the identification and characterization of erectile dysfunction may also be clinically useful for assessing and managing cardiovascular risk. In men with organic erectile dysfunction believed to be vasculogenic in etiology, cardiovascular risk should be further evaluated through assessment of traditional risk factors and noninvasive methods to detect subclinical cardiovascular disease. Cardiovascular risk stratification is now an essential component of clinical management in all men with vasculogenic erectile dysfunction.

References

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  3. Bacon CG, Mittleman MA, Kawachi I, et al. Sexual function in men older than 50 years of age: results from the health professionals follow-up study. Ann Intern Med 2003;139:161-168.
  4. Fung MM, Bettencourt R, Barrett-Connor E. Heart disease risk factors predict erectile dysfunction 25 years later: the Rancho Bernardo Study. J Am Coll Cardiol 2004;43:1405-1411.
  5. Miner M, Nehra A, Jackson G, et al. All Men with Vasculogenic Erectile Dysfunction Require a Cardiovascular Workup. Am J Med 2014;127:174-82.
  6. Feldman HA, Goldstein I, Hatzichristou DG, Krane RJ, McKinlay JB. Impotence and its medical and psychosocial correlates: results of the Massachusetts Male Aging Study. J Urol 1994;151:54-61.
  7. Hatzimouratidis K, Amar E, Eardley I, et al. Guidelines on male sexual dysfunction: erectile dysfunction and premature ejaculation. Eur Urol 2010;57:804-814.
  8. Guay A, Jacobson J. The relationship between testosterone levels, the metabolic syndrome (by two criteria), and insulin resistance in a population of men with organic erectile dysfunction. J Sex Med 2007;4(4 Pt 1):1046-1055.
  9. Seftel AD, Sun P, Swindle R. The prevalence of hypertension, hyperlipidemia, diabetes mellitus and depression in men with erectile dysfunction. J Urol 2004;171(6 Pt 1):2341-2345.
  10. Sun P, Swindle R. Are men with erectile dysfunction more likely to have hypertension than men without erectile dysfunction? A naturalistic national cohort study. J Urol 2005;174:244-248.
  11. Guay AT. ED2: erectile dysfunction = endothelial dysfunction. Endocrinol Metab Clin North Am 2007;36:453-463.
  12. Vlachopoulos C, Aznaouridis K, Ioakeimidis N, et al. Unfavourable endothelial and inflammatory state in erectile dysfunction patients with or without coronary artery disease. Eur Heart J 2006;27:2640-2648.
  13. Yassin AA, Akhras F, El-Sakka AI, Saad F. Cardiovascular diseases and erectile dysfunction: the two faces of the coin of androgen deficiency. Andrologia 2011;43:1-8.
  14. Bohm M, Baumhakel M, Teo K, et al. Erectile dysfunction predicts cardiovascular events in high-risk patients receiving telmisartan, ramipril, or both: The ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial/Telmisartan Randomized AssessmeNt Study in ACE iNtolerant subjects with cardiovascular Disease (ONTARGET/TRANSCEND) Trials. Circulation 2010;121:1439-1446.
  15. Montorsi P, Ravagnani PM, Galli S, et al. Association between erectile dysfunction and coronary artery disease. Role of coronary clinical presentation and extent of coronary vessels involvement: the COBRA trial. Eur Heart J 2006;27:2632-2639.
  16. Ponholzer A, Temml C, Obermayr R, Wehrberger C, Madersbacher S. Is erectile dysfunction an indicator for increased risk of coronary heart disease and stroke? Eur Urol 2005;48:512-518; discussion 517-518.
  17. Salem S, Abdi S, Mehrsai A, et al. Erectile dysfunction severity as a risk predictor for coronary artery disease. J Sex Med 2009;6:3425-3432.
  18. Solomon H, Man JW, Wierzbicki AS, Jackson G. Relation of erectile dysfunction to angiographic coronary artery disease. Am J Cardiol 2003;91:230-231.
  19. Polonsky TS, Taillon LA, Sheth H, et al. The association between erectile dysfunction and peripheral arterial disease as determined by screening ankle-brachial index testing. Atherosclerosis 2009;207:440-444.
  20. Montorsi F, Briganti A, Salonia A, et al. Erectile dysfunction prevalence, time of onset and association with risk factors in 300 consecutive patients with acute chest pain and angiographically documented coronary artery disease. Eur Urol 2003;44:360-364; discussion 364-365.
  21. Baumhakel M, Bohm M. Erectile dysfunction correlates with left ventricular function and precedes cardiovascular events in cardiovascular high-risk patients. Int J Clin Pract 2007;61:361-366.
  22. Hodges LD, Kirby M, Solanki J, O’Donnell J, Brodie DA. The temporal relationship between erectile dysfunction and cardiovascular disease. Int J Clin Pract 2007;61:2019-2025.
  23. Greenstein A, Chen J, Miller H, et al. Does severity of ischemic coronary disease correlate with erectile function? Int J Impot Res. 1997;9(3):123-126.
  24. Hall SA, Shackelton R, Rosen RC, Araujo AB. Sexual activity, erectile dysfunction, and incident cardiovascular events. Am J Cardiol 2010;105:192-197.
  25. Rosen RC, Cappelleri JC, Smith MD, et al. Development and evaluation of an abridged, 5-item version of the International Index of Erectile Function (IIEF-5) as a diagnostic tool for erectile dysfunction. Int J Impot Res 1999;11:319-26.
  26. Greenland P, Alpert JS, Beller GA, et al. 2010 ACCF/AHA guideline for assessment of cardiovascular risk in asymptomatic adults: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation 2010;122:e584-636.
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  29. Buvat J, Maggi M, Gooren L, et al. Endocrine aspects of male sexual dysfunctions. J Sex Med 2010;7(4 Pt 2):1627-1656.
  30. Corona G, Monami M, Boddi V, et al. Low testosterone is associated with an increased risk of MACE lethality in subjects with erectile dysfunction. J Sex Med 2010;7(4 Pt 1):1557-1564.
  31. Shin HW, Park JH, Park JW, et al. Effects of Surgical vs. Nonsurgical Therapy on Erectile Dysfunction and Quality of Life in Obstructive Sleep Apnea Syndrome: A Pilot Study. J Sex Med 2013;10:2053-9
  32. Khafagy AH, Khafagy AH. Treatment of obstructive sleep apnoea as a therapeutic modality for associated erectile dysfunction. Int J Clin Pract 2012;66:1204-1208.
  33. Doherty LS, Kiely JL, Swan V, McNicholas WT. Long-term effects of nasal continuous positive airway pressure therapy on cardiovascular outcomes in sleep apnea syndrome. Chest 2005;127:2076-2084.
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  35. Gupta BP, Murad MH, Clifton MM, et al. The effect of lifestyle modification and cardiovascular risk factor reduction on erectile dysfunction: a systematic review and meta-analysis. Arch Intern Med 2011;171:1797-1803.
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How you bet is affected by your genes .

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by Ashley Yeager
12:09pm, June 17, 2014

Genes that control the brain chemical dopamine have been associated with the bets we make, whether at the poker table or in other areas of life.

When people play a simple betting game, their decisions are influenced by variations in a set of genes that control the brain chemical dopamine, researchers report June 16 in the Proceedings of the National Academy of Sciences.

The finding supports the idea that genetic variation forms an important source of variation in how people make strategic decisions and in other complex behaviors, the scientists say.

New Synthetic Diamonds Are Hardest Gems Ever Created

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Diamonds are the hardest naturally occurring minerals known to man. Even so, scientists are working to make them even tougher, in order to use the sparkling gems as tools for cutting.

Now, a team of researchers, led by Yongjun Tian and Quan Huang at Yanshan University in China, has created synthetic diamonds that are harder, meaning they are less prone to deformation and breaking, than both natural and other man-made diamonds.

Diamonds are the hardest naturally occurring minerals known to man. Even so, scientists are working to make them even tougher, in order to use the sparkling gems as tools for cutting.

Now, a team of researchers, led by Yongjun Tian and Quan Huang at Yanshan University in China, has created synthetic diamonds that are harder, meaning they are less prone to deformation and breaking, than both natural and other man-made diamonds.

To create these tougher-than-steel diamonds, the researchers used tiny particles of carbon, layered like onions, and subjected them to high temperatures and pressures. The resulting diamonds had a unique structure that makes them more resistant to pressure and allows them to tolerate more heat before they oxidize and turn to either gas (carbon dioxide and monoxide) or ordinary carbon, losing many of their unique diamond properties. [In Photos: 13 Mysterious & Cursed Gemstones]

First, a bit about diamonds: Gem-quality diamonds are single crystals, and they are quite hard. But artificial diamonds used on tools are harder still. That’s because they are polycrystalline diamonds, or aggregates of diamond grains called domains, that measure a few micrometers or nanometers across. The grains help to prevent the diamond from breaking, as the boundaries act like small walls that keep chunks of diamond in place. The smaller the domains are, the stronger the diamond.

Tian’s team used the onionlike carbon nanoparticles to make diamonds with domains that are a few nanometers in size and are mirror images of each other. Such “nanotwinned” crystals are much harder than ordinary diamonds, by a factor of two.

The team tested the artificial diamond’s hardness by pressing a pyramid-shaped piece of diamond into the nanotwinned diamond. Tian’s group made a small indentation in their artificial diamond, applying pressures equivalent to nearly 200 gigapascals (GPa) — about 1.9 million atmospheres. An ordinary natural diamond would crush under just half that pressure.

The team also tested how hot the nanotwinned diamond could get before oxidizing. In two different tests, they found that the ordinary diamond began to oxidize at about 1,418 and 1,481 degrees Fahrenheit (770 and 805 degrees Celsius), depending on the testing method. The nanotwinned diamonds didn’t oxidize until they reached 1,796 or 1,932 F (980 or 1,056C).

But not everyone is convinced by these results. Natalia Dubrovinskaia, a professor of material physics at the University of Bayreuth in Germany, said she doesn’t trust the pressure tests. If what Tian’s group is reporting is true, the indenter should have broken, because the material of the indenting tool is not as hard as the nanotwinned diamond, she told Live Science in an email.

Tian disagreed with Dubrovinskaia’s assessment of the indenter. He said that it is possible to measure pressure on the nanotwinned diamond because the indenter was pushed from a vertical position and the amount of shearing force on it wasn’t enough to damage it.

Tian and Dubrovinskaia have “sparred” before; last year, the Yanshan lab said it demonstrated a similar phenomenon, making a form of ultrahard cubic boron nitride. At the time, Dubrovinskaia voiced similar concerns.

Tian, meanwhile, stands by his work. “Indentation hardness of any material can be measured reliably using [a] diamond indenter when the indenter axis is exactly perpendicular to the smooth surface of [the] tested sample,” he said.

Another scientist, Ho-Kwang Mao, of Argonne National Laboratory in Illinois, thinks Tian’s work is valid; he noted that an indenter could reliably measure the hardness of materials much harder than itself.

In addition, the novel part of the work is that such a hard material has been created in a way that can be readily reproduced. “They created a bulk material,” Mao said. “They succeeded in making this and making it harder than diamond — that’s novel.”

To create these tougher-than-steel diamonds, the researchers used tiny particles of carbon, layered like onions, and subjected them to high temperatures and pressures. The resulting diamonds had a unique structure that makes them more resistant to pressure and allows them to tolerate more heat before they oxidize and turn to either gas (carbon dioxide and monoxide) or ordinary carbon, losing many of their unique diamond properties. [In Photos: 13 Mysterious & Cursed Gemstones]

First, a bit about diamonds: Gem-quality diamonds are single crystals, and they are quite hard. But artificial diamonds used on tools are harder still. That’s because they are polycrystalline diamonds, or aggregates of diamond grains called domains, that measure a few micrometers or nanometers across. The grains help to prevent the diamond from breaking, as the boundaries act like small walls that keep chunks of diamond in place. The smaller the domains are, the stronger the diamond.

Tian’s team used the onionlike carbon nanoparticles to make diamonds with domains that are a few nanometers in size and are mirror images of each other. Such “nanotwinned” crystals are much harder than ordinary diamonds, by a factor of two.

The team tested the artificial diamond’s hardness by pressing a pyramid-shaped piece of diamond into the nanotwinned diamond. Tian’s group made a small indentation in their artificial diamond, applying pressures equivalent to nearly 200 gigapascals (GPa) — about 1.9 million atmospheres. An ordinary natural diamond would crush under just half that pressure.

The team also tested how hot the nanotwinned diamond could get before oxidizing. In two different tests, they found that the ordinary diamond began to oxidize at about 1,418 and 1,481 degrees Fahrenheit (770 and 805 degrees Celsius), depending on the testing method. The nanotwinned diamonds didn’t oxidize until they reached 1,796 or 1,932 F (980 or 1,056C).

But not everyone is convinced by these results. Natalia Dubrovinskaia, a professor of material physics at the University of Bayreuth in Germany, said she doesn’t trust the pressure tests. If what Tian’s group is reporting is true, the indenter should have broken, because the material of the indenting tool is not as hard as the nanotwinned diamond, she told Live Science in an email.

Tian disagreed with Dubrovinskaia’s assessment of the indenter. He said that it is possible to measure pressure on the nanotwinned diamond because the indenter was pushed from a vertical position and the amount of shearing force on it wasn’t enough to damage it.

Tian and Dubrovinskaia have “sparred” before; last year, the Yanshan lab said it demonstrated a similar phenomenon, making a form of ultrahard cubic boron nitride. At the time, Dubrovinskaia voiced similar concerns.

Tian, meanwhile, stands by his work. “Indentation hardness of any material can be measured reliably using [a] diamond indenter when the indenter axis is exactly perpendicular to the smooth surface of [the] tested sample,” he said.

Another scientist, Ho-Kwang Mao, of Argonne National Laboratory in Illinois, thinks Tian’s work is valid; he noted that an indenter could reliably measure the hardness of materials much harder than itself.

In addition, the novel part of the work is that such a hard material has been created in a way that can be readily reproduced. “They created a bulk material,” Mao said. “They succeeded in making this and making it harder than diamond — that’s novel.”

What Will We Eat In 2050?

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I remember my first “American-style” fast food. Burger King opened a location in Liverpool and I went out with some friends to check it out. I remember little details like queuing at right angles to the counter rather than snaking along the wall as was typical at the local fish and chip shop. I remember being excited to try the thin and crispy French fries – so unlike the soft British chips. Sadly they had none left by the time I got the front of the queue.

I remember the first time I tried a kiwi fruit. My uncle found them at a local greengrocer and we all sat around wondering what to do with them.

I remember moving to America and discovering supermarket OJ was so much better due to wider implementation of aseptic technologies.

I don’t remember the first time I ate GM food, but now I’ve been eating it half my life.

I remember the first time I went to the IFT food expo seeing just a couple of tiny booths with Chinese companies selling citric acid.  That has changed.

I remember being surprised to see organic produce at a supermarket.

I am 45 years old and the food I eat today is vastly different from the food I ate as a child.  While (or perhaps because) the food itself is cheaper, tastier and more diverse, the burdens of diet-related disease is much worse. Food will continue to change as the world changes. The world I leave to my children will be more crowded, hotter, richer and more connected than the one I was born into. Developing countries have developed and the centers of world power have shifted accordingly.

How will the food we eat change as the world changes and how will the food we eat change the world? FutureFood2050 was put together by the Institute of Food Technologists, where I am a board member, as a way to look for science-based answers to those questions.  The group is interviewing 75 scientists and thought-leaders from across the globe about their work and visions for the future. 

In the most recent series, Pam Ronald, a plant geneticist from UC Davis, argues “the organic vs. genetic engineering debate is a false fight. They both have the same goal, which is ecologically based agriculture.” 

Perhaps with a similar goal, Isha Datar talks about her work growing meat in a culture tube: “…meat production is so wildly inefficient. We feed a cow 7 kilograms of food to get 1 kilogram of beef, not to mention deforestation and that cows are some of the biggest greenhouse gas emitters”.

In other interviews, Caroline Smith DeWaal, describes her work on food safety at CSPI, Michelle Perchonok explains the challenges NASA faces in developing food for future mission to Mars and Marie Wright describes how flavors can be extracted from natural sources and combined to make processed foods tastier.

These women’s ideas and energy seek to transform the way we eat. Whether they succeed or not depends on how consumers and politicians respond. I encourage you to read and think about the future you want to eat.

Google Glass hits surgery arena.

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Surgeons and other clinicians are turning to wearable technologies to improve treatment and patient outcomes.

Much has been made of Google Glass, a lightweight, powerful computer designed to be worn over the eye, as a novel consumer product, but clinical applications are being tested at hospitals nationwide.

At the University of California, San Francisco, lung surgeon Pierre Theodore, MD, wears Google Glass during surgery to access X-rays and other critical data while keeping his eyes on his work.

 Often one will remove a tumor that may be deeply hidden inside an organ — the liver, the lung — for example,” Theodore said in a university press release. “To be able to have those X-rays directly in your field without having to leave the operating room or to log on to another system elsewhere, or to turn yourself away from the patient in order to divert your attention, is very helpful in terms of maintaining your attention where it should be, which is on the patient 100% of the time.”

The Glass eyepiece sits above the wearer’s right eye, without obstructing the entire field of vision. Users can access information using voice commands and taps.

“If my vision is a tic-tac-toe board, it would take one of those upper corners,” Theodore said. “It feels like looking in the rearview mirror of your car. That rear view is always there when I need it, but it’s not there when I don’t.”

Technology innovation firm MedTech Boston recently held a Google Glass challenge among physicians and health care professionals. Video from keynote speakers sharing ways their respective hospitals are implementing the use of the technology recently has been made available.

Rafael J. Grossmann, MD, FACS, a general surgeon from Bangor, Maine, was the first surgeon to use Google Glass in live surgery, with video taken from his Google Glass device broadcast to a nearby iPad. “Google Glass lets you do anything you can do with a smartphone, but with your eyes,” Grossmann said in the video. “Google Glass is really a device that for me, represents the natural evolution of the computing device.”

Grossmann said 440,000 deaths happen annually from medical errors in the US alone, and this type of technology could help prevent those deaths.

“Forty times a week in the US, we have people who have wrong-side surgery, and I really think a device like this has the potential to really shape and improve the way we give health care and the way we teach health care.”

He said vital patient information such as known allergies, blood pressure and other pertinent data in patient records can be accessed with Glass while performing surgery.

Grossmann also said Glass will help more patients to be treated remotely, or by telemedicine. He said in the U.S., about 1 billion doctor visits occur annually. “About 80% of these visits don’t require a physical touch, so having a remote connection really has a reason. That’s why GG has so much potential.”

Theodore shared a similar perspective. “Poor decision-making is a chief source of poor outcomes among patients,” Theodore said. “So I think that’s one way the Google Glass can truly help, by providing data when we need the data.”

NASA Dark-Energy Mission Could Spot 3,000 New Alien Planets

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A mission NASA is designing to probe the nature of mysterious dark energy could discover thousands of alien planets as well.

NASA’s proposed Wide-field Infrared Survey Telescope (WFIRST) mission aims to help researchers better understand dark energy, the puzzling stuff that makes up about three-quarters of the universe and drives its accelerating expansion.

But WFIRST — which is tentatively scheduled to launch in the early to mid-2020s — should also prove to be an adept planet hunter, complementing the activities of the space agency’s prolific Kepler space telescope, researchers say.

“We predict WFIRST will have 3,000 individual planet detections, the same order of magnitude as Kepler,” Scott Gaudi, of Ohio State University, said in April during the Space Telescope Science Institute’s Habitable Worlds Across Time and Space Symposium in Baltimore.

Gravitational microlensing

Scientists detect planets around other stars using several different methods. Kepler notes the tiny, telltale dimming of light that occurs when a planet crosses, or transits, the face of its host star from the spacecraft’s perspective. But WFIRST would rely on gravitational microlensing.

In this technique, astronomers watch what happens when a big object passes between Earth and a background star. The foreground object’s gravity bends and amplifies the light from the background star, acting like a magnifying glass.

If the foreground object is a star, and it has planets, the planets can affect the magnified light, creating a signal that astronomers can detect. The process behind this strategy was laid out in 1936 by Albert Einstein, based on his general theory of relativity.

Earth-based telescopes have already detected more than 20 exoplanets using microlensing. WFIRST will be a space-based telescope, which opens up greater detection abilities, researchers said.

“If you go to space, you can do a lot of great things,” Gaudi said.

Because microlensing requires the correct lineup of foreground and background stars, the ability to follow up on WFIRST’s finds will be limited. However, the process will expand the population of known alien planets, aiding scientists aiming to determine how rare Earth-size planets might be.

“This will dramatically improve our yield of planets,” Gaudi said.

 

A census of worlds

WFIRST should provide a wealth of information about what types of planets exist, allowing stronger statistical conclusions to be drawn, researchers said. Such work would be a nice follow on from Kepler, which has discovered thousands of candidate exoplanets, many of them in solar systems very different than our own.

“If every solar system looked like ours, Kepler would have found very few or no planets,” Gaudi said. “The solar systems we’re learning about with Kepler are very different from our own.”

Kepler has had a great deal of success spotting planets that orbit relatively close to their stars (because they transit frequently). WFIRST, on the other hand, will be more sensitive to larger bodies farther from their suns, researchers said.

In addition, WFIRST should be able to detect smaller distant planets, as well as free-floating “rogue planets” that have been ejected from their systems. Together, Kepler and WFIRST will cover virtually the entire plausible spectrum of planets in mass and orbits.

WFIRST will be able to capture information about Earth-size planets that lie farther from their suns than Earth does, as well as unbound planets the size of Mars. According to Gaudi, in favorable cases, the instrument should be able to detect a terrestrial moon orbiting a distant Earth, or a gas-giant satellite as large as Ganymede (Jupiter’s largest moon), though both observations would be challenging. Unbound moons, like unbound planets, would also be detectable.

Of the 3,000 new planets expected to be found by WFIRST, scientists think about 300 will be Earth-size worlds and 1,000 will be “super-Earths,” possibly rocky planets up to 10 times the mass of our own.  Such predictions are based on present-day understanding of the distribution of types of planets, knowledge that may be either strengthened or challenged by the wealth of data that WFIRST will bring.

With WFIRST, Gaudi said, “we’ll measure the galactic distribution of the planets.”

At present, the observatory is in the pre-formulation stage, where it will remain until 2016. In addition to creating a statistical catalog of exoplanets, WFIRST will also directly image previously confirmed planets, study black holes, and hunt for clues about dark energy.

Metabolic map of human body created

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Weill Cornell Medical College in Qatar (WCMC-Q) scientists have drafted a metabolic map of the human body that shows how human metabolism works as a system, and how it can potentially be modified to treat disease. The map, published in Nature Genetics shows different pathways between genes, enzymes and metabolites, demonstrating that a drug used to target one gene may have several different effects—and consequences—on other pathways.

A single genetic difference in the way that an enzyme behaves may produce positive or . It may make someone prone to certain diseases, or protect them from some illnesses.

“This is an atlas of how everybody is metabolically different. We can now really understand the genetic part of as a whole,” said Dr. Karsten Suhre, a professor of physiology and biophysics at WCMC-Q, who worked with partners at European institutions to create the map.

“To treat a disease, such as diabetes or cancer, if you want to change the levels of a certain metabolite, the map would tell you which to target, but it would also tell you which other metabolites and enzymes surrounding the target would be affected, so that you can select the right combination of drugs in order to reach a desired effect,” he said.

Some 7,824 people participated in the study, helping scientists to determine 2.1 million genetic variants in each participant. Through statistical analysis, scientists found that there are 145 genes that significantly affect the body’s metabolic capacities.

“Many of the 145 genes we identified are enzymes. Enzymes are there to produce the different metabolites—sugars, fats and amino acids are the building blocks the body needs,” Dr. Suhre said. “Genetically, everyone has these enzymes but no one is identical in what concerns their genetic makeup, so we’re looking for differences in what an individual’s enzymes can do by generating a comprehensive picture of over 400 metabolites for every blood sample we measure.”

Stroke Prevention for Women: Start Early .

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Stroke typically affects women in their later years, but doctors are now beginning to focus on helping them cut their risk earlier in life.

This increased attention to risk factors in early adult years was recommended by new guidelines that were released earlier this year by the American Heart Association and the American Stroke Association.

Those guidelines are now being phased into practice by primary care doctors, experts say. For women, that translates to more screening for risk factors during office visits and more interventions to ensure a healthy lifestyle to reduce stroke risk, said Dr. Louise McCullough, director of the Stroke Center at the University of Connecticut in Farmington.

McCullough is the co-author of a summary of the guidelines that was published June 16 in the Annals of Internal Medicine.

Stroke is a serious interruption or reduction of blood flow to the brain, and McCullough said women have “unique risk factors.”

Among them are the use of birth control pills and hormone replacement therapy after menopause, which both increase stroke risk. Pregnancy-associated disorders also may have long-lasting effects on a woman’s health and her stroke risk, she added.

Here’s why all that is important: An estimated 6.8 million persons in the United States have had a stroke, 3.8 million of whom are women, according to the summary. Women have poorer recovery and worse quality of life than men after a stroke, the summary says.

And here’s what women can expect if their primary care doctor adheres to the new guidelines.

Your doctor will screen for high blood pressure. It is the most changeable risk factor, and it’s more common in women than in men.

Depending on your age, your doctor may screen for atrial fibrillation, an abnormal heart rhythm, by measuring pulse rate and doing an electrocardiogram.

Your doctor may ask you about any history of headaches. Migraine headache with aura can increase stroke risk, and McCullough said reducing the frequency of migraine should be the goal as a possible way to reduce stroke risk.

Certain pregnancy-related conditions affect risk, McCullough said. “If you have pregnancy-induced high blood pressure, you are fourfold more likely to develop high blood pressure in adulthood and two times more likely to have a stroke,” she said. Keeping blood pressure under control is crucial.

Stroke during pregnancy is not common, but experts have found the risk is highest in the 12 weeks after giving birth. So women who have a new headache, blurred vision or other unusual symptoms should be checked out.

Depression and emotional stress also boost stroke risk, McCullough said, so your doctor should ask about that, too.

The guidelines also recommend focusing on a healthy lifestyle that helps prevent stroke. These measures include keeping weight at a healthy level, eating a healthy diet, not smoking, getting regular physical activity and keeping alcohol intake moderate, if women drink.

“This article is going to be very helpful in getting the message out to the primary care physicians,” said Dr. Ravi Dave, director of interventional cardiology at the University of California Los Angeles Medical Center in Santa Monica.

He noted that some of the risk factors for stroke may be news to women, such as the link between depression and stroke. “I would encourage these patients with depression to get treated for it,” he said.

In recent years, Dave said, researchers have been pinpointing differences in heart attack symptoms between men and women. Now, the same thing is happening with risk factors for strokes, teasing out the gender differences. For women, the message is clear, he said: Alert your doctor if you have any of these stroke risk factors, or suspect you do.