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Thursday, August 30, 2012

Telling Body Time

A new method could make assessing a person’s circadian rhythms easier, paving the way for increased drug effectiveness.

By Hayley Dunning |
FLICKR CREATIVE COMMONS, AARON GELLER
Circadian rhythms dictate the 24-hour shifts in gene expression, protein levels, and various cellular processes throughout the day, such as melatonin affecting our sleep-wake cycle. Such changes in cell activity—in particular, cyclical changes in metabolism— can greatly influence the effectiveness of a drug and the severity of its side effects, depending on when it is administered.
However, each individual has unique circadian timing, with “body time” being offset by as much as 6 hours between people, making it difficult—if not impossible—for doctors to consider when giving drugs. Previous attempts to assess a person’s body time have relied on intense, repeated sampling procedures impractical for clinical applications. But in a study published yesterday (August 27) in the National Academy of Sciences proceedings, researchers have demonstrated a new method that requires only two blood samples taken 12 hours apart.
“Due to a combination of genetics and environment, there is a wide diversity of clock times among humans, from morning larks to night owls,” chronobiologist Steven Brown of the University of Zurich, who was not involved in the study, said in an email. “It would be advantageous to have a simple method to accurately determine clock time before a particular treatment, particularly for a toxic one like chemotherapy of cancer.”
Determining where in the cycle a person’s body clock is at any given time typically involves measuring melatonin and/or cortisol levels. These chemicals show robust patterns over a 24-hour period. However, random sampling must be done continuously for more than a day under controlled environmental conditions to determine the patient’s baseline levels. In the new study, Hiroki Ueda and colleagues at the RIKEN Center for Developmental Biology in Kobe, Japan, measured as many oscillating metabolites as possible to create a chart of how they fluctuate in proportion.
The concept is based on 16th-century botanist Carolus Linnaeus’ flower clock. “Each flower has different timing for opening and closing,” said Ueda. Linnaeus reasoned that if he knew when a range of flowers opened and closed in a day, he could create a garden to tell the time. “Likewise,” Ueda said, “each metabolite has different timing, so I applied this concept to the human body.”
Three study participants had blood samples taken every hour for 1.5 days, under normal sleep-wake conditions and then again after their normal cycles had been disrupted by a forced 28-hour sleep-wake schedule. Such disruption of natural circadian cycles is known to occur in shift workers or people travelling between time zones, and can cause weight gain and obesity, metabolic abnormalities and diabetes, and even heart disease.
The researchers measured the levels of 58 metabolites by liquid chromatography-mass spectrometry and used radioimmunological assays to assess cortisol and melatonin levels. The metabolites, whose levels cycled in participants during their normal cycles, were tracked against patterns of melatonin and cortisol to calibrate the metabolite levels with the body clock. The researchers then drew up a table based on the proportions of metabolites across body times, and used it to estimate the body time of study participants using just two samples taken 12 hours apart. During both disrupted and normal cycles, the team estimated body times within 3 hours of real body time, as shown by the traditional cortisol/melatonin method involving sampling as often as every 20 minutes.
“In principle, the method holds great promise to replace the cumbersome melatonin assay,” said Brown. “In practice, however, the method is still in its infancy.” The method has still limited the accuracy of liquid chromatography-mass spectrometry, for example, and more work is required to verify this proof of concept result.
But Ueda hopes he can move forward and scale up the study to track the metabolites of thousands of participants and build a comprehensive metabolite timetable. Such a massive dataset could reduce body clock estimation to a single sample per patient, and may help make the practice common in clinical settings. “My small dream is that internal body time is going to be one of the ways for your health to be checked,” he said.
T. Kasukawa et al., “Human blood metabolite timetable indicates internal body time,” Proceedings of the National Academy of Sciencesdoi: 10.1073/pnas.1207768109, 2012.
Posted by
Robert Karl Stonjek

Dharmam - Tamil Short film (With English subtitles)

Confucius


Confucius

 

"விஜயனின் வருகை'' சிறப்பு தபால் தலை

ஈழத்தின் ஆதி குடிகள் தமிழர்கள் தான் என்பதற்கான ஆதாரம் 

1956-ல் "விஜயனின் வருகை'' என்ற தலைப்புடன் சிறப்பு தபால் தலை ஒன்றை இலங்கை அரசு வெளியிட்டது. குவேனி ஒரு மரத்தடியில் அமர்ந்திருப்பது போலவும், கப்பலில் வந்த விஜயன் அவளிடம் அடைக்கலம் கோருவது போலவும் இந்த தபால் தலை அமைந்திருந்தது



Non-infectious diseases hit the globe


BURNET INSTITUTE   
RTimages_-_ECG
“There is a common view that only people in wealthy nations die from NCDs but it is a new epidemic in low-to-middle income countries that needs to be addressed.”
Image: RTimages/iStockphoto
Non-communicable diseases (NCDs) such as heart disease, cancer and diabetes are no longer just a problem in wealthy nations – the rate of NCDs in low-to-middle income countries are increasing faster than in developed countries.

This major public health issue was the focus of the Director’s Seminar presented by Professor Rob Moodie from the University of Melbourne’s School of Population Health.

“Globally 14.2 million people between the ages of 30 and 69 die each year prematurely from diseases which are preventable. Risk factors for these diseases include tobacco use, unhealthy diets and physical inactivity,” Professor Moodie told a packed audience at Burnet.

“There is a common view that only people in wealthy nations die from NCDs but it is a new epidemic in low-to-middle income countries that needs to be addressed.”

Professor Moodie said it was particularly concerning to be told recently by a surgeon at a hospital in Fiji that he was amputating one leg a day from patients suffering sepsis related to diabetes.

“Seven trillion dollars of lost output in developed countries is attributable to NCDs,” he said.

“We need to start looking at these new epidemics as they are major global problems that should have our attention.”

Professor Moodie founded Burnet’s Centre for International Health in 1995.

Current head of the Centre, Professor Mike Toole said it was Professor Moodie’s unique vision that laid the foundation for the continued success and impact of the Centre’s work.
Editor's Note: Original news release can be found here.

Maa Paapalu Tolaginchu song - Sri Shiridi Saibaba Mahatyam Video Song Wi...

கடல் கடந்து கொடி கட்டி ஆண்ட இனம் நம் தமிழினம்

மேலைநாட்டவர் வெறும் வாணிபத்துக்காகவே கீழைநாடுகளை நாடிக்கொண்டிருந்த நாட்களில், கடல் கடந்து கொடி கட்டி ஆண்ட இனம் நம் தமிழினம். காம்போஜம்(கம்போடியா), ஸ்ரீவிஜயம்(சுமாத்திரா), சாவகம்(ஜாவா), சீயம்-மாபப்பாளம்(தாய்லாந்து), கடாரம்(மலேசியா), நக்காவரம்(நிக்கோபார் தீவுகள்), முந்நீர்ப்பழந்தீவு(மாலைதீவு) போன்ற தூரதேச நாடுகளிலெல்லாம், தமிழ் மூவேந்தரில் ஒருவரான சோழரின் புலிக்கொடி பறந்து அந்நாட்டவரெல்லாம் தமிழருக்கு திறை செலுத்தி பணிந்துநின்ற ஒரு பொற்காலம் சரித்திரத்தில் இடம்பிடித்திருக்கிறது. அவ்வாறு சிறந்திருந்த சோழப்பேரரசு தொடர்ந்து நீடிக்காததன் காரணம், போருக்கும் ஆக்கிரமிப்புக்கும் தொடர்ந்து ஆதரவளித்ததும் ஏனைய தமிழரசரான சேரர்-பாண்டியருடன் ஒற்றுமையின்றி இணங்கி நடக்காமையுமே என்பது அதே சரித்திரம் நமக்கு தரும் பாடம்.

வரலாறு சுட்டிக்காட்டிய அதே தவற்றை, மீண்டும் மீண்டும் இன்று வரை தொடர்ந்து நாம் செய்துகொண்டிருப்பதுதான் மீண்டெழ முடியாத ஆழத்தில் நாம் வீழ்ந்துகிடப்பதன் காரணம்.

ஒற்றுமையின்மை…..!!!

Wednesday, August 29, 2012

PHD POSITIONS IN OPTIMISATION at NICTA VRL, VICTORIAN UNIVERSITIES, AUSTRALIA


PHD POSITIONS IN OPTIMISATION at NICTA VRL, VICTORIAN UNIVERSITIES, AUSTRALIA==============================================================================================================================

National ICT Australia (NICTA) is Australia's Information and Communications Technology Research Centre of Excellence. NICTA is offering scholarships for exceptional PhD students working in the priority area of Optimisation at a number of Victorian universities. NICTA offers both full and top-up scholarships on top of base scholarships at Victorian Universities.
Optimisation
The optimisation research group at NICTA VRL, led by Professor Pascal Van Hentenryck, at the University of Melbourne, is recognised as a world-class team with pioneering contributions in fields such as constraint programming, hybrid optimisation, and planning. The group currently offers attractive PhD scholarships for high-calibre students interested in contributing to their research effort. The group focuses on grand challenges in disaster management, future energy systems, and multi-modal supply chains. Fundamental and applied research is conducted in continuous and discrete optimisation, decision making under uncertainty, simulation and 3D-visualisation, and algorithmic decision theory. Optimisation and decision-support platforms are being developed that will bring unprecedented support for decision making in complex environments.

NICTA Optimisation Research Group homepage:http://www.nicta.com.au/research/optimisation


For further information please contact Pascal Van Hentenryck, Optimisation Research Group Leader: pvh@nicta.com.au<mailto:pvh@nicta.com.au>

Application procedure:

Please follow the instructions at http://www.nicta.com.au/education/scholarships/victoria_research_lab


Applications and questions should be directed to vrlschols@lists.nicta.com.au<mailto:vrlschols@lists.nicta.com.au>

Elisabeth Wejsflog Paintings

 Artist Elisabeth Wejsflog


.

A devoted artist for more than 30 years. Polish born Elisabeth currently lives in Sweden since 1976… Beneath follows a brief description of her background and work.


"The studio is located in the street level of a more than hundred years old house near the Saint Pauli Church in the park avenue Kungsgatan in Malmoe, Sweden. She works with prints as well as oil and acrylic on canvas and watercolours. 'I wanted to be a musician once', Elisabeth says.
It is airy and has to be caught in the flight. Elisabeth uses watercolour crayons as a compliment to the colours to be able to work fast and light-handed.

The art critic Stig Åke Stålnacke gives the following words about Elisabeth Wejsflog in a catalogue:

'Emotion is the only thing that counts to this woman, who is mighty of creating such dramatic paintings. Everything else has been cleaned out, and what remains is a woman travelling through life with Passion as her only luggage.'"



Chopin is her favourite composer. She and the composer have this in common, that both left their home country Poland in their youth. If Chopin painted with music, then Elisabeth paints music. She has been well known through her visits with paper and watercolours at the rehearsals of the Malmoe Symphonics. A large number of her works has been created right there. The paintings contain both figurative and abstract elements. What the eye can see can be transformed into hints of the environment. What the ear hears and the heart feels are turned into forms, movements, colours, a kind of conclusion of the tone impressions. 'I do not paint the musicians', she says, 'It is the Music'. It is not possible to grip it, keep it, and then paint it



Scope