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2014 in review

December 31, 2014 Leave a comment

The WordPress.com stats helper monkeys prepared a 2014 annual report for this blog.

Here’s an excerpt:

The concert hall at the Sydney Opera House holds 2,700 people. This blog was viewed about 10,000 times in 2014. If it were a concert at Sydney Opera House, it would take about 4 sold-out performances for that many people to see it.

Click here to see the complete report.

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Team prevents memory problems caused by sleep deprivation

December 13, 2014 Leave a comment

The hippocampus of a mouse in the University of Pennsylvania study glows green where cells have taken up a receptor that triggers a cAMP signalling pathway. After administering the ligand to the receptor, researchers could selectively boost cAMP levels in this region and this cell type only. They found that ‘rescuing’ these cells with a shot of cAMP preventing the memory problems that sleep loss can induce. Credit: University of Pennsylvania

Sleep is a critical period for memory consolidation, and most people don’t get enough. Research has shown that even brief periods of sleep deprivation can lead to deficits in memory formation.

In a new study, published in the Journal of Neuroscience, a team led by scientists from the University of Pennsylvania found that a particular set of cells in a small region of the brain are responsible for memory problems after sleep loss. By selectively increasing levels of a signaling molecule in these cells, the researchers prevented mice from having .

Robbert Havekes was the lead author on the study. He is a research associate in the lab of Ted Abel, the study’s senior author and Brush Family Professor of Biology in Penn’s School of Arts & Sciences. Coauthors from the Abel lab included Jennifer C. Tudor and Sarah L. Ferri. They collaborated with Arnd Baumann of Forschungszentrum Jülich, Germany, and Vibeke M. Bruinenberg and Peter Meerlo of the University of Groningen, The Netherlands.

In 2009, a group from Abel’s lab published a study in Nature that identified the cyclic AMP, or cAMP, signaling pathway as playing a role in sleep-loss-associated . Whereas depriving mice of sleep impaired their spatial memory, restoring levels of cAMP in their brain prevented this effect.

“The challenge following this important study,” Abel said, “was to determine if the impact of  was mediated by particular regions of the brain and particular neural circuits. We suspected that the hippocampus, the brain region that mediates spatial navigation and contextual memory, was critical.”

In the current work, they set out to answer these questions. They targeted excitatory neurons because of their importance in transmitting signals in the brain and the fact that their functioning relies on cAMP signaling. The limitation of previous studies was that they lacked a way to increase cAMP in just one area of the brain in a cell-type specific fashion. Havekes, Abel and colleagues devised a way of doing this that they term a “pharmacogenetic” approach, blending genetic modification and drug administration.

They engineered a non-pathogenic virus to harbor the gene encoding the receptor for the protein octopamine, which triggers cAMP pathway activation in fruit flies but is not naturally found in the brains of mice. The researchers injected this virus into the hippocampus of mice so that the excitatory neurons in that region alone would express the octopamine receptor.

“It sounds weird. Why would you put a receptor there that is never going to be activated?” Havekes said. “The trick is, you follow that up by giving mice the ligand of the receptor, which is octopamine, and that will activate the receptors only where they are present.”

The team confirmed that only the excitatory hippocampal neurons expressed the receptor and that they could selectively increase cAMP levels in only these cells by giving the mice a systemic injection of octopamine.

“This way, we could manipulate the cAMP pathways that we previously saw being affected by sleep deprivation but selectively in specific neural circuits in the brain,” Havekes says.

With this pharmacogenetic tool in hand, Havekes, Abel and colleagues began the sleep deprivation tests with the mice expressing the octopamine receptor in their hippocampus. First the researchers trained mice in a spatial memory task. They put them in a box that had three different objects, each in a distinct location.

Then, because previous research had shown that cAMP signaling contributes to hippocampus-dependent  in two time windows—first directly after training and again three to four hours after training—the researchers gave mice in the experimental groups injections of octopamine in both of these windows to boost cAMP levels.

Mice receiving the cAMP boost were divided into two groups: One was left to sleep undisturbed, while the other was sleep-deprived for five hours by gently tapping their cage or rearranging their bedding.

One full day after the initial training, all of the mice were tested again. This time, there was a twist: one of the objects originally in the box had been moved to a new location.

“If the mice had learned and remembered the location of the objects during their training, then they would realize, okay, this is the object that has moved, and they’ll spend more time exploring that particular object,” Havekes explained. “If they didn’t remember well, they would explore all the objects in a random fashion.”

The researchers found that the sleep-deprived mice that received the octopamine injections spent more time exploring the object that had moved, just as mice that had not been sleep deprived did. On the other hand, sleep-deprived  that didn’t express the receptor explored all the objects at random, a sign that they had failed to remember the locations of the objects from their initial training as a result of the brief period of sleep deprivation.

“What we’ve shown is this memory loss due to sleep deprivation is really dependent on misregulation of cAMP signaling in the excitatory neurons of the hippocampus,” Havekes said.

As a next step, the group would like to explore what cAMP is doing to help consolidate memory. They would also like to investigate how other cell types in the brain, such as astrocytes, might be affected. And finally, while this study focused on the impact of a brief period of sleep deprivation, Havekes is curious to know how not getting enough sleep on a daily basis, as is more similar to human experiences, might be affecting .

“Thinking about people who do shift work or doctors who work long hours, if we can tackle the cognitive problems that result from , that would be a great thing,” Havekes said.

“At least in the mouse using these sophisticated tools, we’re able to reverse the negative impact of sleep deprivation on cognition,” Abel said.

Nanotechnology against malaria parasites

December 13, 2014 Leave a comment

After maturation, malaria parasites (yellow) are leaving an infected red blood cell and are efficiently blocked by nanomimics (blue). (Fig: Modified with permission from ACS)

Malaria parasites invade human red blood cells, they then disrupt them and infect others. Researchers at the University of Basel and the Swiss Tropical and Public Health Institute have now developed so-called nanomimics of host cell membranes that trick the parasites. This could lead to novel treatment and vaccination strategies in the fight against malaria and other infectious diseases. Their research results have been published in the scientific journal ACS Nano.

For many infectious diseases no vaccine currently exists. In addition, resistance against currently used drugs is spreading rapidly. To fight these diseases, innovative strategies using new mechanisms of action are needed. The  Plasmodium falciparum that is transmitted by the Anopheles mosquito is such an example. Malaria is still responsible for more than 600,000 deaths annually, especially affecting children in Africa (WHO, 2012).

Artificial bubbles with receptors

Malaria parasites normally invade human red  in which they hide and reproduce. They then make the host cell burst and infect new cells. Using nanomimics, this cycle can now be effectively disrupted: The egressing parasites now bind to the nanomimics instead of the red blood cells.

Researchers of groups led by Prof. Wolfgang Meier, Prof. Cornelia Palivan (both at the University of Basel) and Prof. Hans-Peter Beck (Swiss TPH) have successfully designed and tested host cell nanomimics. For this, they developed a simple procedure to produce polymer vesicles – small artificial bubbles – with host cell receptors on the surface. The preparation of such polymer vesicles with water-soluble host receptors was done by using a mixture of two different block copolymers. In aqueous solution, the nanomimics spontaneously form by self-assembly.

Blocking parasites efficiently

Usually, the malaria parasites destroy their host cells after 48 hours and then infect new . At this stage, they have to bind specific host cell receptors. Nanomimics are now able to bind the egressing parasites, thus blocking the invasion of new cells. The parasites are no longer able to invade host cells, however, they are fully accessible to the immune system.

The researchers examined the interaction of nanomimics with malaria parasites in detail by using fluorescence and electron microscopy. A large number of nanomimics were able to bind to the parasites and the reduction of infection through the nanomimics was 100-fold higher when compared to a soluble form of the host cell receptors. In other words: In order to block all , a 100 times higher concentration of soluble host  is needed, than when the receptors are presented on the surface of nanomimics.

“Our results could lead to new alternative treatment and vaccines strategies in the future”, says Adrian Najer first-author of the study. Since many other pathogens use the same  receptor for invasion, the nanomimics might also be used against other . The research project was funded by the Swiss National Science Foundation and the NCCR “Molecular Systems Engineering”.

More information: Adrian Najer, Dalin Wu, Andrej Bieri, Françoise Brand, Cornelia G. Palivan, Hans-Peter Beck, and Wolfgang Meier. “Nanomimics of Host Cell Membranes Block Invasion and Expose Invasive Malaria Parasites.” ACS Nano, Publication Date (Web): November 29, 2014 | DOI: 10.1021/nn5054206

Medical Tourists Flock to Thailand Spurring Post-Coup Economy

December 13, 2014 Leave a comment

Visitors throng the famed Damnoen Saduak floating market, outside of Bangkok. Tourism accounts for 10 percent of Thailand’s gross domestic product. Photographer: Cedric Arnold/Bloomberg Markets

Monica Topliss pauses while eating breakfast in her Bangkok hotel to explain why she flew 7,300 kilometers from her home in Australia to go under a Thai plastic surgeon’s knife.

“The whole thing, airfares and hotel included, cost me 15,000 Australian dollars ($13,050), when back home, it would have been twice as much,” Topliss, a 48-year-old executive chef and author of cookbooks, says of the breast enhancement procedures and cosmetic dentistry she has just undergone. “And the surgeon did such a good job. It’s like the clock has been turned back 20 years. What’s more, I’m having a wonderful two-week holiday as well. Even the hospitals are like five-star hotels.”

Come for the gold-spired temples and sun-kissed beaches; stay for the low-cost, U.S.-accredited medical services. Or vice versa. That’s the Land of Smiles today, Bloomberg Markets magazine will report in its December issue. Foreigners seeking treatment for everything from open-heart surgery to gender reassignment have made Thailand the world’s No. 1 destination for so-called medical tourism, luring as many as 1.8 million overseas visitors in 2013, according to Patients Beyond Borders, a consulting firm based in Chapel Hill, North Carolina.

That ranks Thailand, a developing nation with a per capita gross domestic product of just $5,700, ahead of the U.S. — and also Thailand’s more prosperous Southeast Asian neighbors, Singapore and Malaysia — as the preferred destination for international patients. Last year, medical tourists pumped as much as $4.7 billion into the Thai economy, according to government statistics. “While the U.S. is still first choice for the ultrarich, Thailand is unquestionably No. 1 among everyone seeking affordable care,” Patients Beyond Borders founder Josef Woodman says.

Nurses prepare a suite at Bangkok Hospital. From here, a medical tourist — of whom Thailand sees hundreds of thousands a year — can be whisked to a five-star hotel.

Investor Goodwill

Medical tourism is far from the only industry in which Thailand punches above its weight. The country is also among the world’s biggest exporters of products as diverse as computer disk drives, canned tuna, rice and rubber. It’s the region’s leading auto manufacturer and last year ranked as one of the top 10 global tourist destinations.

These strengths have earned Thailand considerable goodwill among investors, who have proved willing to stick with it even through months of political and social trauma. In the past year, the country has been shaken by deadly street protests, a military coup, three months of negative growth and a slump in tourism, which accounts for 10 percent of GDP. Even so, the benchmark SET Index jumped 22 percent this year through Nov. 18, compared with a 1.7 percent fall in the MSCI Emerging Markets Index.

Prayuth Chan-Ocha, formerly chief of the Thai army, is now the country’s prime minister and head of the Board of Investment. PORNCHAI KITTIWONGSAKUL/AFP/Getty Images

‘So Far, So Good’

All while a junta steers the economy. “It’s so far, so good,” says Mark Mobius, executive chairman of San Mateo, California–based Templeton Emerging Markets Group. Mobius, who oversees about $45 billion from his offices in Hong Kong and Singapore, is so bullish on Thailand that he has made the nation of 68 million the largest geographical component of his $13.2 billion Templeton Asian Growth Fund, ahead of China and India.

Apart from strengths in manufacturing, agriculture and tourism, Mobius is also impressed by Thailand’s resilience in the face of previous political and economic shocks. “I think they will pull through, like they have in the past,” he says.

Medical tourism is doing its part. A gauge of 15 Thai hospital stocks, boosted by medical tourism, leapt 54 percent in 2014 as of Nov. 18. Among the prime beneficiaries of these soaring valuations are three of Thailand’s billionaire dynasties.

Hospital Stocks

They include the family of the late Chaleo Yoovidhya, who in 1987 co-founded Red Bull GmbH, the world’s biggest energy-drink company, with Austrian billionaire Dietrich Mateschitz. The media-shy Yoovidhyas, whose 51 percent stake in Red Bull is worth about $10 billion, according to the Bloomberg Billionaires Index, own Bangkok’s Piyavate Hospital, where Topliss underwent her breast surgery.

Prasert Prasarttong-Osoth, 80, a physician-turned-entrepreneur who founded Bangkok Airways Co. (BA), Thailand’s oldest private carrier, owns 20 percent of Bangkok Dusit Medical Services Pcl (BGH), Thailand’s largest hospital operator. Bangkok Dusit stock rose 55 percent through Nov. 18. And the Sophonpanich family, whose patriarch, Chin Sophonpanich, founded Bangkok Bank Pcl, Thailand’s biggest lender by assets, owns 45 percent of Bumrungrad Hospital Pcl. (BH) Shares in Bumrungrad, which markets itself as Southeast Asia’s largest private health-care facility, have also jumped 55 percent this year.

‘Really Upbeat’

“Hospital operators are among our top picks,” says Peerapong Jirasevijinda, who helps manage $15 billion at Bangkok-based BBL Asset Management Co. “We are still really upbeat even though they have rallied so much recently.”

The Thai military, which has staged 12 coups since 1932, hasn’t always inspired such confidence in investors. After the previous putsch, in 2006, the junta briefly imposed capital controls, prompting fund managers to dump stocks. This time, investors have been betting that the current crop of generals, led by army chief–turned–Prime Minister Prayuth Chan-Ocha, will get it right. In September, foreigners were net buyers of Thai stocks for a third straight month. The $657.1 million inflow was the highest since December 2012, although that was followed by an outflow of nearly $500 million in October.

Prayuth, 60, seized power on May 22, following six months of street protests against the elected government of Yingluck Shinawatra. He has thus far kept a lid on Thailand’s seemingly unbridgeable divisions between the urban elite and rural poor.

Martial Law

Since 2006, the country has repeatedly been thrown into turmoil by demonstrators representing color-coded rival factions — the so-called Yellow Shirts largely backed by the Bangkok middle classes and royalist establishment and the Red Shirt supporters of the populist former prime ministers Yingluck and her brother Thaksin, both of whom won elections only to have their governments deposed by coups. In the worst incidents, 92 people died when Red Shirts occupying Bangkok’s city center were driven out by the military in 2010, and Yellow Shirts shut down airports for a week in 2008, stranding 400,000 travelers. Prayuth has declared martial law and has succeeded in keeping protesters off the streets.

The general has also placed himself on the front line in the battle to revive an economy that shrank 2.2 percent in the first quarter of 2014. Appointing himself head of the Board of Investment, he promptly signed off on $4 billion of foreign investment that had been awaiting approval from the government he deposed. He also pledged to press ahead with his own, modified version of a $60 billion, 10-year program to upgrade railways, roads and ports.

Infrastructure Spending

Under Prayuth, Thailand has avoided a technical recession in 2014, growing 1.1 percent in the three months ended on June 30 and another 1.1 percent in the quarter ended Sept. 30. In October, Sommai Phasee, Prayuth’s finance minister, predicted that the economy would end up growing 2 percent in 2014.

Investors are betting the government’s infrastructure spending will provide a bonanza for the nation’s construction companies. As of Nov. 18, the SET’s Thai Construction Services Index had joined health-care stocks in jumping more than 50 percent for the year. The largest company in the index, Ch. Karnchang Pcl (CK), had soared 82 percent, and the second biggest, Sino-Thai Engineering & Construction Pcl (STEC), had doubled in value.

Such investor euphoria may be premature, according to former Thai Finance Minister Korn Chatikavanij. Korn, a former Thailand chairman of JPMorgan Chase & Co., says the junta’s policies are too conservative to stimulate the economy; he predicts the stock market’s run will end soon because there is no assurance when the country will return to more-growth-focused civilian rule.

Major Challenges

Prayuth has said elections won’t be held until at least late 2015 and then only after his junta approves a new constitution and enacts unspecified measures to “reform” Thai politics and society. “The market will do well over the long term but disappoint before that,” Korn says.

The country’s rulers are facing major economic challenges, according to Siam Commercial Bank Pcl (SCB), Thailand’s biggest lender by market value. While the government has predicted the economy will grow 4.5 percent in 2015, Sutapa Amornvivat, SCB’s chief economist, said at a conference in October that she believed growth will average only 3.5 percent in the medium term. Sutapa said Thailand would struggle to overcome high levels of household debt, an aging workforce, a slowing Chinese economy and increased competition from faster-growing Southeast Asian neighbors. The World Bank is also downbeat, predicting Thailand will grow 1.5 percent this year and 3.5 percent in 2015 — slower than any other major Asian economy.

Royal Succession

On Oct. 6, Thais were reminded of another risk — an inevitable royal succession — when King Bhumibol Adulyadej, the world’s longest-reigning monarch, underwent surgery to remove his gall bladder. Since ascending to the throne in 1946, the revered Bhumibol, 86, has been an enduring presence through coups and revolving-door civilian regimes. His heir is Crown Prince Maha Vajiralongkorn, 62. Though palace officials pronounced the king’s surgery a success, Thai stocks fell 1.7 percent that day.

Amid such challenges, medical tourism is one industry in which Thailand can compete — on services, prices and style. Patients flying into Bangkok’s Suvarnabhumi Airport are greeted at special arrival desks before being whisked to hospitals where, in grand hotel-type lobbies, English-speaking concierges, as well as interpreters skilled in some 30 other languages, shepherd them to private rooms.

Five-Star Hotels

Once discharged, patients can recuperate in five-star hotels that charge as little as $100 a night. Medi Makeovers, a Sydney-based medical travel agency, is now the biggest corporate customer of Bangkok’s 500-room Grande Centre Point Hotel Terminal 21, according to Somchai Meesri, the hotel’s general manager.

“They take 10 percent of our rooms, ahead of Japanese clients such as Toyota and Honda,” says Somchai, whose hotel is owned by Land & Houses Pcl (LH), Thailand’s biggest residential property developer. Medical tourists also stay longer, resting up after their procedures. “The average stay for other guests is three nights,” Somchai says. “For medical tourists, it is 10.”

Though Thailand has long aspired to medical excellence — the present king’s father graduated as an M.D. from Harvard University in 1927 — it wasn’t until 1997 that it began to tap a global market. That year, Bumrungrad opened the 500-bed Bumrungrad International Hospital with money borrowed in U.S. dollars. Six months later, Thailand was at the epicenter of the Asian financial crisis. The Thai baht collapsed along with the domestic market for premium private hospital care. “Our U.S.- dollar debt doubled on a local-currency basis,” says Chai Sophonpanich, Bumrungrad’s chairman.

Wooing Foreigners

In desperation, the hospital began to woo wealthy foreigners and expatriates living in nearby Asian countries, where medical services were less developed. Then, after the Sept. 11, 2001, attacks in the U.S., a new market in the Middle East opened up. “Patient flow increased as a result of more-stringent immigration policies by the USA and European countries for Middle East travelers,” Chai says. Within a decade, the number of Bumrungrad’s Middle Eastern patients leapt to 130,000 a year from 20,000. In 2002, Bumrungrad became the first hospital in Asia to win accreditation from the Joint Commission International, the global arm of the main standards-setting body for U.S. hospitals. Since then, 29 more Thai hospitals have also received that accreditation, including Bumrungrad’s main rival, Bangkok Hospital, the flagship of Bangkok Dusit.

‘Fantastic Treatment’

Last year, Bumrungrad attracted 250,000 medical tourists, including 20,000 Americans and 8,000 Australians. Three weeks after paying $7,500 to have her nose reshaped and breasts enhanced in Bangkok, Australian Calli Graham sips coffee beside Sydney’s Bondi Beach and declares herself content. “It’s the best money I ever spent,” Graham, 30, says. “I got fantastic treatment and the satisfaction of knowing I am helping the economy of a developing country. It’s a win-win.”

The above story is reprinted from materials provided by Bloomberg.