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Friday, 14 May 2010

Low Testosterone linked to Poor Sleep; Beneficial Effects of Testosterone for Frailty


Poor Sleep in Aging Men Linked to Lower Testosterone

When men reach age 30, testosterone levels begin to drop by 1 to 2 percent annually, researchers say. Coincidentally, many men begin to complainat around age 40 about the quality of their sleep. Are the two linked?

Yes, one new study concludes.

The research revealed a link between testosterone levels in men over 50 and the amount of deep sleep they report.
"Deep sleep is when the recuperation of body and mind is optimal,"said study leader Zoran Sekerovic, a graduate student from theUniversity of Montreal Department of Psychology.

In young men, deep sleep represents 10 to 20 percent of total sleep, Sekerovic explained in a statement. By age 50, it decreases to as little as 5 percent. For menover 60, it can disappear altogether, the study found.

The study didn't find any correlation with other parts of the sleep cycle: falling asleep, light sleep, or paradoxical sleep, when most dreams occur. Men in their 20s don't have such a correlation, because their neuronal circuits are intact, the thinking goes.

"With age, there is neuronal loss and the synchronization ofcerebral activity isn't as good, which is why there is a loss of deep sleep," Sekerovic explained. "Low levels of testosterone intensify the lack of synchronization and can explain 20 percent of men's inability to experience deep sleep."

Sekerovic suggests dwindling testosterone levels are what impact sleep,not vice-versa, as other studies have suggested. He adds previous investigations measured daily fluctuations in testosterone levels,which are higher in the morning.

If his findings are true, there could be treatment options.

"The loss of deep sleep is a serious problem that could be treated with testosterone. That would be tremendous progress," he said. "But hormone therapy can have secondary effects.Therefore, it will be essential to better understand the mechanisms leading to the loss of deep sleep."

Other scientists have suggested, however, that older people need less sleep.

This study, announced Friday, was supervised by Julie Carrier, aprofessor of psychology at the University of Montreal. The findingswere presented at the annual conference of the Association francophone pour le savoir (ACFAS).

By LiveScience Staff
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Beneficial Effects of Testosterone for Frailty in Older Men Are Short-Lived, Study Finds

ScienceDaily (Nov. 4, 2010) — The beneficial effects of six months of testosterone treatment on muscle mass, strength and quality of life in frail elderly men are not maintained at six months post-treatment, according to a study accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology & Metabolism (JCEM).

Frailty is an age-related state of physical limitation caused by the loss of muscle mass and function and can lead to adverse clinical outcomes such as dependency, institutionalization and death. Testosterone levels naturally decline with aging and testosterone replacement is a common therapy. Short-term testosterone treatment in frail elderly men has been shown to improve muscle mass and strength, but until now it has been unclear whether these effects could be maintained post-treatment.

"Since the use of testosterone in elderly men raises concerns regarding adverse effects on the prostate and cardiovascular system, it's important to determine if short-term treatment can lead to prolonged benefits beyond the duration of testosterone exposure," said Frederick Wu, MD, of the University of Manchester in the United Kingdom and lead author of the study. "Our findings suggest it may not be possible to break or interrupt the cycle of decline in physical function in frailty by short-term anabolic pharmacological intervention using testosterone supplementation for six months."

In this study, researchers evaluated 274 intermediate-frail and frail elderly men aged 65-90 years with low testosterone levels. Study participants received either a testosterone gel or placebo for six months. 
Assessments were carried out at baseline, the end of treatment and six months after treatment cessation. Researchers found that the increased lean body mass, muscle strength and quality of life after six months of testosterone treatment were not maintained six months after treatment.

"At present, the optimal duration of anabolic hormonal intervention to produce sustained benefits in treating frailty in older men is unknown," said Wu. "To best interrupt the downward spiral into frailty a greater emphasis should be placed on a multi-disciplinary interventional approach including resistance exercise, diet and other lifestyle options, in conjunction with pharmacological agents."

Other researchers working on the study include: Matthew O'Connell, Steven Roberts, Upendram Srinivas-Shankar, Abdelouahid Tajar, Judith Adams and Jackie Oldham of the University of Manchester in the United Kingdom; and Martin Connolly of the University of Auckland in New Zealand.

The article, "Do the Effects of Testosterone on Muscle Strength, Physical Function, Body Composition and Quality of Life Persist Six Months Post-treatment in Intermediate-Frail and Frail Elderly Men," will appear in the February 2011 issue of JCEM.

Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.

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    Thursday, 13 May 2010

    Breakthrough in tissue engineering: 'Bio-Legos'

    MIT-Harvard Division of Health Sciences and Technology researchers produced tube-shaped tissue by grouping cells into polymer 'bricks' that hardened when illuminated.
    (Credit: Javier Gomez-Fernandez/MIT)
     
    Researchers have been working on the problem of tissue engineering for years because the payoff would be so great. The ability to construct new organs would mean that patients won't necessarily have to wait for transplants.

    But growing cells in lab dishes that are three-dimensional instead of flat has proved to be incredibly tricky. One group, however, claims to have made a major breakthrough.

    The solution, according to a team at the MIT-Harvard Division of Health Sciences and Technology (HST), could be as simple (but incredibly elegant) as building the equivalent of biological Legos, whose structures far more closely resemble real, complex tissue.

    The new technique, which they're calling "micromasonry," is showcased this May in the journal Advanced Materials.

    Javier Gomez-Fernandez
    (Credit: MIT)
     
    According to former HST postdoctoral associate Javier Gomez-Fernandez, obtaining single cells to engineer tissue requires breaking tissue apart via enzymes that digest the material that holds cells together. Once those cells are free they don't easily (or quickly) reassemble into structures that mimic natural tissue architecture.

    So the HST team built what it's dubbing "biological Legos," coating the freed cells with a liquid version of polyethylene glycol (PEG), which acts as a glue and also hardens when illuminated. Once coated, they could be arranged into cubes and exposed to light to hold that shape.

    The team then coated those cubes with the PEG polymer again to glue the cubes together and squeeze them onto a scaffold surface, and illuminated the cubes a second time so that they would harden into this tube-like shape, a three-dimensional structure that could function as capillaries and transport blood to organs.

    The breakthrough is not only that they are creating 3D structures, but that they can place cells in any position they want to make specific shapes. "So it's not just that it's a scaffold, it's that you can arrange them into very specific shapes through specific distributions of cells," Gomez-Fernandez says.

    This isn't the first time complex tissue architecture has been created in a lab; other researchers have developed a technique called organ printing to accomplish this, but it requires new (read: expensive) equipment. Micromasonry, on the other hand, does not. "You can reproduce this in any lab," Gomez-Fernandez says in the MIT news release. "It's very simple."

    To make micromasonry clinically useful, the team is investigating different cellular structures as well as different polymers that might provide more control over cell placement than PEG currently allows.

     
    Elizabeth Armstrong Moore is a freelance journalist based in Portland, Ore. She has contributed to Wired magazine, The Christian Science Monitor, and public radio. Her semi-obscure hobbies include unicycling, slacklining, hula-hooping, scuba diving, billiards, Sudoku, Magic the Gathering, and classical piano. She is a member of the CNET Blog Network and is not an employee of CNET. 
     
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    Schoolgirl Jessica Watson due home after solo round-the-world sail

    Celebrations and just a hint of controversy await 16-year-old Australian as she sails into Sydney after seven months at sea

    The Pink Lady, in which Australian schoolgirl Jessica Watson  sailed around the world

    Jessica Watson's yacht, the Pink Lady, rounds the southern tip of Tasmania in the closing stages of her solo round-the-world trip. Photograph: Rex Features

    A crowd of thousands will line the quayside while hundreds of boats will form a "nautical red carpet". The celebrations in Sydney on Saturday promise to rival those of its spectacular new year displays as Australia welcomes home Jessica Watson, at 16 the youngest sailor ever to circumnavigate the globe single-handed.

    Or is she? As the Queensland teenager's yacht, Ella's Pink Lady, sails into Sydney harbour after an epic seven-month voyage, the TV helicopters hovering above will not be the only thing clouding blue skies. Controversy hangs in the air.

    Experienced old salts have queried whether Watson, who arrives back three days shy of her 17th birthday, has sailed far enough, claiming her route falls some 2000 nautical miles short of a true circumnavigation according to the rules set by the global authority, the World Sailing Speed Record Council. She didn't travel far enough north of the equator, they have calculated.

    So she has failed, they declare, in her stated aim to beat the 1999 record of fellow Aussie Jesse Martin, which he set over 328 days at the age of 18.

    It's a moot point. Following the furore over allowing ever younger sailors to undertake such a risky endeavour, sparked when the Dutch courts intervened last year to prevent Laura Dekker, 13, from setting sail solo, the WSSRC no longer recognises the category of "the youngest".

    So Watson will claim no record. But at stake are the millions she could, potentially, earn as a result of her highly-publicised venture. One of Rupert Murdoch's Australian papers has bought her exclusive story for a reported A$700,000 (£430,000), and a TV station has exclusive live rights. Watson, who has been sailing since she was eight, will step off her yacht and into a whirlwind nationwide "Meet Jessica" tour. A book is due out in July.

    Meanwhile her website is doing brisk trade in baseball hats, wall charts and other sailing paraphernalia. It boasts 14 major sponsors, and the apple growers Pink Lady Australian hope she will become the company's poster girl.

    According to navigation experts at the respected Sail-world.com magazine, Watson will have travelled 18,265 nautical miles, but a valid circumnavigation requires 21,600.

    That is not to detract from her otherwise remarkable achievement and raw guts, the magazine said.

    But it added that, though her log may show she has travelled 23,000 nautical miles, as claimed by her PR team, this includes "tacking and gybing", and not the straight line distances required.

    Their claims have led to ill-tempered exchanges with Watson's PR manager Andrew Fraser, and criticism from the many Watson supporters gripped by her journey.

    "We are not really interested in the technical concerns of a minority," wrote Fraser in an email to Sail-world.com. "The rising tide of her supporters is a millions multiple of the minority." As the council wouldn't be recognising her record anyway, her team argue, she does not need to adhere to their rules. And by their calculation, she has met all the requirements. Watson has brushed off the controversy. "Call me immature but I've actually been having a bit of a giggle over the whole thing," she wrote on her blog. "If I haven't been sailing around the world, then it beats me what I've been doing out here all this time."

    Critics say they do not blame Watson but rather her PR team for the ambiguity over the world record status. Sail-world.com points out that Watson's website had originally stated she had "set her sights on beating Jesse's record", but have now replaced the world "record" with "achievement".

    Unofficial polls meantime show that 75% of Australians believe she is a record breaker – whatever the rules.
    Watson sailed out under a cloud. She collided with a coal freighter during a test sail, leading to claims she was inexperienced. Critics say her feat could set a bad example and encourage even younger children, and her parents were decried for encouraging her.

    But waiting for her on the quayside will be her British friend and fellow sailor Mike Perham, who last year became the youngest to sail around the world, aged 17. Jesse Martin will also be there – with his record still, seemingly, intact.

    Extracts from Jessica Watson's blog

    24 April 2010 Despite the fact that today started with a knockdown, a wet bunk, a headache and some pretty huge seas, I've had a great day.
    8 April 2010 Some bad news today … the handle has fallen off my only kettle.
    22 Nov 2009 I've finally got a fish … I can't say there would be many fishermen who would be proud of the mess I made of filleting it.
    17 Nov 2009 Let me introduce you to "Silly". He's a little brown seabird. Silly earned his nickname because of his fascination with the wind generator and his amusing attempts to land on the bendy windvane blade.
    12 Nov 2009 I was told this was the most watched blog in Australia and stage fright has left me a bit speechless.
    2 Nov 2009 After completing the first English assignment I sent it off to discover I'd opened the wrong bag and have been working on next year's assignments, oops!

    Australia hails Jessica Watson, 16, for sailing record

    Crowds cheer Jessica as she arrives in Sydney
    Australians have gathered around Sydney harbour to welcome back teenager Jessica Watson from her record round-the-world sailing adventure.

    The 16-year-old is said to be the youngest person to sail non-stop, solo and unassisted around the world.
    But her record has been questioned with claims that she has not sailed far enough.

    She will also not be recognised by the World Speed Sailing Record Council, as it has ended its under-18 category.

    Wearing pink

    Ms Watson sailed into Sydney harbour on Saturday, seven months after leaving on an arduous voyage some critics said was too dangerous for someone so young.

    If I haven't been sailing around, then it beats me what I've been doing out here all this time!
    Jessica Watson's blog
    Thousands of well-wishers lined the harbour and watched from boats as Ms Watson sailed her pink, 10m (34ft) yacht Ella's Pink Lady over the finishing line.

    Family, friends and Australian Prime Minister Kevin Rudd have gathered to greet her. Many of the onlookers wore pink to match the boat.
    Many more Australians are watching the event broadcast live on television.

    "It's like the day before Christmas," she wrote in her blog before she arrived.

    "Except I don't ever remember getting this excited about Christmas."

    She left Sydney on 18 October, defying critics who said she was being irresponsible for taking on such a difficult voyage at such a young age.

    Also meeting her in Sydney is Briton Mike Perham, who last year at the age of 17 completed his own solo around the world voyage in nine months.

    Ms Watson's support team says she has sailed nearly 23,000 nautical miles but the influential Sail-World website said she had not gone far enough north of the equator to claim a true circumnavigation of the globe, according to the rules of the World Speed Sailing Record Council.

    The council only recognises feats achieved by people over 18.

    On her blog, Ms Watson said: "If I haven't been sailing around, then it beats me what I've been doing out here all this time!"

    Ms Watson has reportedly sold her story to Rupert Murdoch's News Limited for A$700,000 ($625,000).

    Map showing sailors Mike Perham's and Jessica Watson's routes  around the world
     

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