terça-feira, 2 de dezembro de 2014

How to stop the spread of HIV in Africa

 

While Ebola has attracted much of the world's attention recently, a severe HIV epidemic rages on around the world and in sub-Saharan Africa in particular. Globally, more than 34 million people are infected with HIV; in sub-Saharan Africa alone, 3 million new infections occur annually.

In an attempt to stop the spread of HIV, governments in the region are considering providing antiretroviral drugs to people who do not have the virus but are at risk for becoming infected. Such drugs are known as pre-exposure prophylaxis, or PrEP.

Although the conventional strategy -- attempting to attempt to distribute the drugs to people in every city and village -- might seem logical and equitable, researchers at UCLA have devised a plan they say would be much more effective in reducing HIV transmission.

The strategy, developed using a complex mathematical model, focuses on targeting "hot zones," areas where the risk of HIV infection is much higher than the national average. In South Africa, where 17 percent of the population is infected with HIV, the model predicted that targeting hot zones would prevent 40 percent more HIV infections than using the conventional strategy -- and would therefore be 40 percent more cost-effective.

"Stopping the HIV pandemic is one of the greatest challenges facing the global community," said Sally Blower, the paper's senior author and the director of the Center for Biomedical Modeling at the UCLA Semel Institute for Neuroscience and Human Behavior.

The report appears in the current online edition of Nature Communications.

"Since results from clinical trials have shown that antiretroviral drugs are effective in protecting individuals against HIV, the big question now is how best to use them," said David Gerberry, the study's first author and a former UCLA postdoctoral fellow who now is an assistant professor in mathematics at Xavier University.

To develop the strategy, UCLA researchers designed a computer model that calculated and mapped the incidence of HIV in South Africa and identified hot zones. The model featured three important components: the geographic dispersion of the population, the geographic variation in the severity of the HIV epidemic and the geographic variation in the level of risk behavior. The model revealed that two of South Africa's nine provinces are hot zones.

The researchers then used the model to predict where, and how many, new HIV infections would occur based on using either the conventional strategy or a strategy targeting hot zones for distributing the drugs.

"Our results are quite striking," Blower said. "Both strategies would provide PrEP to the same number of people, but using the hot zones plan would prevent 40 percent more HIV infections than using the conventional plan."

Gerberry said the team's strategy could be applied to other nations as well. "The methods we developed can be used to find hot zones in any other sub-Saharan countries that have geographic variation in the severity of their HIV epidemic, such as Lesotho, Botswana, Nigeria and Uganda," he said. "Once the hot zones have been found in these countries, our spatial optimization algorithm can be used to identify the geographic targeting strategy that would be the most cost-effective."

Blower said the study holds great significance for global health policy. "The findings show that, when interventions are rolled out, governments in sub-Saharan Africa will have to choose between maximizing equity in access to the drugs and minimizing transmission of HIV."


Story Source:

The above story is based on materials provided by University of California, Los Angeles (UCLA), Health Sciences. Note: Materials may be edited for content and length.


Journal Reference:

  1. David J. Gerberry, Bradley G. Wagner, J. Gerardo Garcia-Lerma, Walid Heneine, Sally Blower. Using geospatial modelling to optimize the rollout of antiretroviral-based pre-exposure HIV interventions in Sub-Saharan Africa. Nature Communications, 2014; 5: 5454 DOI: 10.1038/ncomms6454

 

Green light from FDA for CT lung-imaging software

 

 

A comparison of different patients' lungs, imaged using the U-M/Imbio technique. The red and yellow areas show reduced ability to push out air.

A technology that started in a University of Michigan Medical School lab may soon help lung disease patients around the world breathe a little easier, by helping their doctors make a clearer diagnosis and more individualized treatment plan.

Imbio, a startup launched from the University of Michigan in 2007, has just received clearance from the U.S. Food and Drug Administration to sell its software platform based on U-M research. Called Lung Density Analysis or LDA, it analyzes images of patients' lungs with detailed precision.

The new FDA 510(K) clearance allows doctors to use Imbio's LDA system in patients with chronic obstructive pulmonary disease or COPD, which affects over 60 million people worldwide.

The software allows doctors to carefully analyze a patient's CT (computed tomography) lung scan and look at how their disease is affecting their ability to fill their lungs with air and to push it out when they exhale. The company is also developing techniques for analyzing other lung images, and images of cancerous tumors, to guide treatment using variations of the same technology.

Not only does the technology have its roots in the U-M Department of Radiology's Center for Molecular Imaging, it was also tested thoroughly by a separate team of U-M Health System lung-imaging experts.

Together, they published the results of their in-depth testing in the journal Nature Medicine in 2012.

The technology grew out of basic laboratory research at U-M by the company's co-founders, Brian Ross, Ph.D., and Alnawaz Rehemtulla, Ph.D. Both now act as scientific advisors to Imbio.

"It's incredibly gratifying to see this concept grow from an idea in our lab, to a product ready for market," says Ross. "We look forward to seeing how clinicians worldwide can use the LDA approach to benefit patients, and we're grateful to all who have helped this concept reach this exciting point through many years of research and product development." He credited the university's research and technology transfer environment for helping the concept reach the marketable stage.

Ella Kazerooni, M.D., chief of cardiothoracic imaging at UMHS, led the clinical evaluation of the technology, using images from the COPDGene trial that involved thousands of COPD patients around the country.

"This groundbreaking technique reveals functional information about the lung's performance that is not available through other means and will allow us to tailor more individualized treatment for these patients," says Kazerooni. "We are very excited to see the technique launched as a commercial product, after years of development in our image processing lab and extensive clinical research in thousands of COPD patients."

The LDA approach uses powerful computer techniques to overlay the CT scan taken during a full inhalation with an image taken during a full exhalation. The overlaid, or registered, CT images share the same geometric space, so that the lung tissue in the inflated and deflated lungs aligns. The density of healthy lung tissue will change more between the two images than the density of diseased lung, allowing researchers to create a three-dimensional "map" of the patient's lung function

The software assigns colors to each small 3-D area, called a voxel, according to the difference in signal changes within each of the areas between the two scans. Green means healthy, yellow means a reduced ability to push air out of the lung's small air sacs, and red means severely reduced ability.

Ross is the Roger A. Berg Research Professor of radiology and professor of biological chemistry at the U-M Medical School, while Rehemtulla is the Ruth Tuttle Freeman Research Professor of Radiation Oncology. Kazerooni is a professor of radiology and member of the Institute for Healthcare Policy and Innovation.

Ross and Rehemtulla have a financial interest in the company, but do not receive salary or consulting income. Kazerooni has no financial interest in the company or involvement in its operations. The University has a financial interest in the company via its licensing agreement.

Unravelling the complexity of proteins

 

 

December 1, 2014

International Union of Crystallography

Knowledge of the three-dimensional structures of proteins is essential for understanding biological processes. Structures help to explain molecular and biochemical functions, visualize details of macromolecular interactions, facilitate understanding of underlying biochemical mechanisms and define biological concepts. A new article seeks to address the fundamental question of whether the three-dimensional structures of all proteins and all functional annotations can be determined using X-ray crystallography.


Knowledge of the three-dimensional structures of proteins is essential for understanding biological processes.

Structures help to explain molecular and biochemical functions, visualize details of macromolecular interactions, facilitate understanding of underlying biochemical mechanisms and define biological concepts.

The human genome and follow-up sequencing projects have revolutionized biology and medicine; structural genomic programmes have developed and applied structure-determination pipelines to a wide range of protein targets, facilitating the visualization of macromolecular interactions and the understanding of their molecular and biochemical functions.

A paper recently published by Mizianty et al. seeks to address the fundamental question of whether the three-dimensional structures of all proteins and all functional annotations can be determined using X-ray crystallography.

The researchers set out to perform the first large scale analysis of its kind covering all known complete proteomes (the sets of proteins thought to be expressed by an organism whose genome has been completely sequenced, as defined by the UniProt Consortium in 2012) and all functional and localization annotations available in the Gene Ontology for the corresponding proteins.

The Canadian and US team show that current X-ray crystallographic knowhow combined with homology modeling can provide structures for 25% of modelling families (protein clusters for which structural models can be obtained through homology modelling), with at least one structural model produced for each Gene Ontology functional annotation. The coverage varies between super-kingdoms, with 19% for eukaryotes, 35% for bacteria and 49% for archaea, and with those of viruses following the coverage values of their hosts. It is shown that the crystallization propensities of proteomes from the taxonomic super kingdoms are distinct. The use of knowledge-based target selection is shown to substantially increase the ability to produce X-ray structures.

Talking to the IUCr Mizianty commented "We believe our method has helped to advance our understanding of the coverage by X-ray structures of proteins and complete proteomes on a global scale."


Story Source:

The above story is based on materials provided by International Union of Crystallography. Note: Materials may be edited for content and length.


Journal Reference:

  1. Marcin J. Mizianty, Xiao Fan, Jing Yan, Eric Chalmers, Christopher Woloschuk, Andrzej Joachimiak, Lukasz Kurgan. Covering complete proteomes with X-ray structures: a current snapshot. Acta Crystallographica Section D Biological Crystallography, 2014; 70 (11): 2781 DOI: 10.1107/S1399004714019427

 

10 Foods That Help You Sleep Better

 

 

When too many nights spent tossing and turning cause you to dread your bedroom, instead of looking forward to slipping between the sheets, there’s no need to automatically reach for a sleeping pill. Instead, change your bedtime snack to a food known for its sleep-enhancing properties, and you’ll soon be visiting the land of Nod.

glass of milk with a straw - Steven Errico/Photographer's Choice RF/Getty Images

Steven Errico/Photographer's Choice RF/Getty Images

1. Milk

A glass of warm milk has always been a bedtime staple, and for good reason. It’s loaded with calcium, which not only helps your muscles relax; it also regulates your body’s production of melatonin. Plus, milk contains the amino acid tryptophan, which is the precursor to serotonin, a hormone that promotes relaxation and a feeling of calm.  Enjoy a glass of milk – it’s extra soothing when it’s warm – before bedtime, or drink a glass if you wake up during the night. 

cherries.jpg - RS Photography/Getty Images

RS Photography/Getty Images

2. Cherries

Cherries, especially the tart cherries used for baking pies, contain melatonin, the hormone that helps you sleep soundly. To reap the benefits, eat a helping of cherries an hour or two before bedtime, or drink a cup of tart cherry juice twice daily. 

walnut.jpg - Susie McCaffrey/Getty Images

Susie McCaffrey/Getty Images

3. Walnuts

These tasty tree nuts contain melatonin, the hormone that helps regulate your sleep cycle. In addition, they provide a helping of tryptophan, which converts to melatonin in your body. Enjoy a handful of walnuts an hour or so before bedtime, and enjoy a restful night.

almonds.jpg - Daniel Grill/Getty Images

Daniel Grill/Getty Images

4. Almonds

Almonds are an excellent source of magnesium, which helps you relax, and protein, which keeps blood sugar levels even throughout the night. Additionally, a daily handful of almonds lowers bad cholesterol levels, boosts brain activity and strengthens your bones.  

lettuce.jpg - Richard Clark/Getty Images

Richard Clark/Getty Images

5. Lettuce

While salad may not be a traditional bedtime snack, it’s a surprisingly effective one. That’s because lettuce, especially romaine lettuce, contains a phytonutrient called lactucarium, which is said to induce sleep, relieve pain and promote relaxation. If munching on a salad before bedtime isn’t appealing, you can brew lettuce tea by pouring very hot water over romaine leaves, then letting them steep for ten minutes before adding a touch of honey for sweet flavor.

cheese.jpg - Davies and Starr/Getty Images

Davies and Starr/Getty Images

6. Cheese

Like all dairy products, cheese contains calcium, which helps relieve stress and relax muscles, along with regulating your body’s production of melatonin. With so many cheeses to choose from, you can enjoy a different variety each night. Limit yourself to a few small cubes, or two or three slices of cheese on whole-wheat crackers. 

hummus.jpg - A.J.J. Estudi/Getty Images

A.J.J. Estudi/Getty Images

7. Hummus

This Mediterranean chickpea staple is not only delicious; it’s also a good source of tryptophan. Enjoy a few teaspoons of hummus on whole-wheat crackers a few hours before bedtime, and you’ll reap the benefits of steady blood sugar levels, sleep-inducing hormones and protein to soothe any acid reflux – a common cause of insomnia. 

bananas.jpg - Dave Higginson/Getty Images

Dave Higginson/Getty Images

8. Bananas

Sweet, portable, inexpensive and loved by just about everyone – what’s not to like about bananas? Even better, they pack a hefty punch of magnesium and potassium; two minerals that help relax muscles and promote sleep. Plus, bananas are a good source of tryptophan. Enjoy a small banana an hour or two before bedtime.

rice.jpg - Foodcollection/Getty Images

Foodcollection/Getty Images

9. Jasmine Rice

Rice might not be your first thought when considering a bedtime snack, but jasmine rice is actually a good way to promote shuteye. It’s a high-glycemic food, meaning it releases glucose into your bloodstream at a slow, steady pace, rather than raising your sugar levels high and letting them crash back down. This keeps your brain fueled for the night. Jasmine rice also boosts levels of tryptophan and serotonin, both important for restful sleep. If a bowl of plain rice doesn’t appeal to you, mix in a bit of milk and honey.

honey.jpg - Lew Robinson/Getty Images

Lew Robinson/Getty Images

10. Honey

This sweet stuff is the bee’s knees when it comes to helping you get to sleep. Honey’s sugar raises insulin slightly, allowing tryptophan to more easily enter the brain where it works its magic in helping induce restful sleep. Simply eat a tablespoon of raw honey before bedtime, preferably on an otherwise empty stomach. If that’s too much sweetness to tolerate, stir the honey into a cup of chamomile tea.

Top 10 cycling innovations of 2014

 

 

top-10-cycling-innovations-2014-16

Bygen's Hank Direct Bike features a one-of-a-kind drivetrain along with a telescoping frame, and it was one of our picks for this year's list

Bicycle historians, take note – it's time once again to look back at 10 of the bike-related products that most caught our attention over the past year! As with our lists from 2012 and 2013, these aren't necessarily things that we think are destined to be big sellers. In fact, it's entirely possible that this might be the last you hear of many of them. We like 'em, though, because they're examples of what happens when people dare to try something different ... and that sort of spirit is the reason why we're not still all riding penny farthings.

Schwalbe Procore tire system

top-10-cycling-innovations-2014-2

Setting a mountain bike's tire pressure is a bit of a balancing act ... too hard, and the tires won't provide decent traction – too soft, and they're likely to get pinch flats, plus they might not stay seated on the rim. As a result, cyclists usually compromise and keep them at a "somewhere-in-between" air pressure.

The Procore system, however, allows for the best of both extremes. A high-pressure tube within the tire helps protect against flats and keeps everything in place, while an air space between that tube and the inside wall of the tire can be kept at a very low pressure, allowing for excellent traction.

Price: Approx. US$230/pair

Zackees turn-signaling gloves

top-10-cycling-innovations-2014-10

If you want to let motorists know where you're heading on the road, it definitely helps to use hand signals. Zackees are designed to make sure that those signals get noticed.

The back of each glove contains a waterproof array of high-intensity LEDs arranged to form a blinking directional arrow. The lights are activated by touching a pair of metal contacts together – one on the inside of the glove's thumb, and one on the inside of its index finger.

Price: $75

Calfee Design tandem/single convertible bikes

top-10-cycling-innovations-2014-1

Some couples like to bring a tandem bike along on their travels, so they can ride together without having to lug around two complete bikes. Should one of those people want to go out on a solo ride, however, they're stuck using that big ol' tandem. That's why Calfee Design started building tandems that can temporarily be converted to singles.

The back end of the carbon fiber frame is simply removed by hand via two couplers, the rear wheel is transferred over, and the bicycle-built-for-two becomes a single-seater. Calfee has only made a couple of the bikes so far – both custom orders for the same client – which was reflected in their cost.

Price: Approx. $25,000

Skylock solar-powered lock

top-10-cycling-innovations-2014-7

Mechanical key-activated locks are so 2013. The Skylock instead communicates with the user's smartphone via Bluetooth or Wi-Fi, unlocking either once they press an onscreen button, or even just when their phone gets within close proximity of the lock. Users can additionally grant access to friends who wish to borrow their bike, allowing their smartphones to also unlock the Skylock.

The lock's battery can be charged via USB, although the built-in solar panel reportedly requires just one hour of exposure to sunlight to deliver enough of a charge to provide one week's worth of use. As an added bonus, an integrated accelerometer detects movements associated with both crashes and theft attempts, and responds by contacting the user's phone to check that everything's OK.

Price: $159

Bygen Hank Direct Bike

top-10-cycling-innovations-2014-17

When it comes to converting pedaling power into wheel revolutions, belt drives are certainly a cleaner, smoother alternative to chains – but they're not the only other way to go. In its Hank Direct Bike, Korean manufacturer Bygen utilizes levers that run from the pedals to the rear hub via an articulated linkage. Although it's a direct-drive system, riders don't need to constantly keep pedaling like they do on a fixie, plus they can switch between three gears.

Another one of the Hank's unique features is its carbon fiber frame, the cockpit length of which can be adjusted by sliding the rear end towards the front. This design also allows the bike to be tipped back and stored vertically.

Price: $5,000

Shimano XTR Di2 electronic shifting

top-10-cycling-innovations-2014-9

This was the year that Shimano took its existing Di2 electronic shifting system for road bikes and adapted it for use in the company's XTR mountain bike group. As with the road version, this one electronically relays signals from the shifters to motors in the front and rear derailleurs. This means that shifts are consistently quick and smooth, as they aren't affected by the slackening of stretched steel cables or by contaminants within the cable housings.

Additionally, using the Shimano Synchronized Shift function, the system can shift both the front and rear derailleurs at once via a single shifter. Similar functionality is offered by IXOW's Synchrobox.

Price: TBA

patchnride flat-patching tool

top-10-cycling-innovations-2014-5

Ordinarily, fixing flat tires is quite the hassle ... you have to remove the wheel, unseat the tire, pull out the tube, find and patch the hole, and then put everything back together. With patchnride, however, the wheel and tire can be left in place. You just inject a patch onto the tube, right through the hole in the tire – the whole process reportedly takes less than one minute.

Price: $30

Fluent suspension wheel

top-10-cycling-innovations-2014-8

Although commuter bikes generally don't have suspension forks or frames, it's still nice if they're able to smooth out the ride a little. Tel Aviv-based manufacturer SoftWheel wants to help them do so, via their wheels. The company's Fluent wheel features three cylindrical shock absorbers that radiate out from the hub to the rim, taking the place of spokes. They remain rigid when going over smooth surfaces, but compress when the wheel takes particularly big hits.

Price: Approx. $2,000/pair

Imprint moldable grips

top-10-cycling-innovations-2014-N

Handlebar grips probably aren't something that you give a lot of thought to. They're just tubes of rubber that make it easier to hold onto the bar – how much room for improvement could there be? Well, more than you might think.

TMR Designs' Imprint Grips are custom-molded to the shape of the user's hands, ensuring an even contact area with a minimum of uncomfortable pressure points.

We tried them out for ourselves, and can definitely attest to the fact that they do make a difference.

Price: Approx. $40 and up

Nuseti sealed-drivetrain mountain bike

top-10-cycling-innovations-2014-H

As we mentioned earlier, there's no denying that belt drives are quieter and less grimy than chains. According to Polish mountain biking medalist Gregory Zielinski, however, chains are still a sturdier, more efficient way to go. In order to address their shortcomings, he created the Nuseti – it has a chain, but it's sealed within an oil bath that keeps it continuously lubricated and protected from contaminants.

Additionally, due to the inclusion of a 16-speed planetary gearbox, the chain never has to move sideways between chainrings or cassette sprockets. This greatly lessens the chances of it breaking, as it minimizes the amount of mechanical stress to which the chain is subjected.

Zielinski was raising production funds for the Nuseti on Kickstarter, and unfortunately was unable to meet his project goal. It's still an intriguing concept, however, and one that we may yet see reach the market in one form or another.

Honorable mentions

top-10-cycling-innovations-2014-P

This was a Top 10 list, but what if it had been a Top 15? Well, we probably would have included things like ...

  • IDSG Engineering and Trading's MC2 bike, that can be set into eight different frame configurations
  • Cycliq's Fly6 tail light, which also continuously shoots and records video that can be used as evidence against hostile drivers
  • Vanhawk's sensor-laden carbon fiber Valour "smart" bike, the navigation system of which guides riders via LED indicators on the handlebars
  • The linear-drive MaynoothBike, that replaces the crankset with pedals that slide up and down the sides of the fork, powering the front wheel
  • Inspired Cycle Engineering's Full Fat trike, modeled after the fat-trike that British adventurer Maria Leijerstam used to cycle to the South Pole

Three Tips for Better Sleep: Overcome your Insomnia - republishing -

 

 
Sleep techniques, how to sleep well, sleep therapy, CBT-I

Published on October 15, 2013 by Jonathan Fader, Ph.D. in The New You

“When I woke up this morning my girlfriend asked me, “Did you sleep good? I said “No, I made a few mistakes.” - Steven Wright

First, you are not alone. A shocking 50-70 million people living in the USA have sleep difficulties of some kind. But not to worry, there are some very practical strategies that you can use if you would like to try change your behaviors to improve your sleep. As Steven Wright joked, we all make mistakes in our sleep related behaviors. This post will review some of the tools used in Cognitive Behavioral Therapy for Insomnia (CBT-I) to get started towards a more restful night tonight!

1. Retrain your mind and body for sleep.

If you can’t sleep, then get up and do something instead of lying there worrying. It’s the worry that gets you, not the lack of sleep. - Dale Carnegie

When we lie sleeplessly in bed our brain begins to associate bed with sleeplessness. Stimulus control therapy works to retrain your brain how to sleep. There are some guidelines you can follow on your own that can really help in this area. First, avoid using your bed for anything (ok almost anything!) except sleep. Secondly, if you are in bed awake for more than 20 minutes, get up and sit in a chair outside of the sleeping area and participate in a non-activating activity in low light. For example reading, crafting, or implementing a relaxation exercises. Try not to use anything with a screen.

Sleep Hygiene can also contribute to training your body to sleep. One healthy step towards this is to develop a nighttime ritual. Having a cup of tea (decaffeinated), taking a warm shower, stretching, changing into specific pajamas before bed can all help send messages to your brain that it is time to go to sleep.

2. Manage your stress and worry.

Man should forget his anger before he lies down to sleep. - Mahatma Gandhi

Stress and anxiety can create substantial barriers to sleep. Some tools that you can use during your day and near bedtime to reduce worry and stress are breathing exercises and muscle relaxation exercises. Both of these tools can help to reduce stress and induce relaxation which will help you prepare your body and mind to rest.

Worry time: Pick a scheduled time to worry and write your worries down. If you think of something during the rest of the day, tell yourself you will worry about that during your “worry time.” If you must, take a minute to write down your worry at that time.

Lastly, don’t look at the clock while sleeping! This can lead to increased pressure and worry about sleeping. I have had clients that go so far as to put the clock in another part of the room or put tape over the screen to avoid temptation.

3. Daily Activities and next steps

A well spent day brings happy sleep - Leonardo da Vinci

What you do during the day does affect the quality of your sleep. There is plenty of evidence that supports the fact that exercising during the day can help you sleep better. Also, napping during the day can negatively affect your nighttime sleep.

One of the main ideas of Cognitive Behavioral Therapy for Insomnia is the idea of “sleep efficiency” which basically means the proportion of time that you are actually asleep while in bed. In CBT-I you work with a therapist to help you create a “sleep debt” (a need to fall asleep) by allowing yourself less time (opportunity) to be in bed. This results in being tired while in bed and thus, eventually sleeping more.

Hopefully some of these tips will be helpful for you. Certainly a consultation with a clinician who has expertise in CBT-I can help you guide yourself to a night of restful sleep.

Sweet Dreams!

New hope for MS sufferers: Drug shown to alleviate symptoms in mice

 

 

Seema Tiwari-Woodruff, associate professor of biomedical sciences at the UC Riverside Scho...

Seema Tiwari-Woodruff, associate professor of biomedical sciences at the UC Riverside School of Medicine (Photo: I. Pittalwala, UC Riverside)

 

Researchers are zeroing in on what looks like an effective treatment for the symptoms of Multiple Sclerosis. Teams from UC Riverside and New York's Rockefeller University have both used the same compound, indazole chloride, to successfully reverse the progression of MS in mice. The drug appears to be able to stimulate the regeneration of the myelin sheath – the nerve pathway coating that is progressively destroyed as MS attacks the nervous system.

MS affects around 400,000 people in the United States alone, and some 2.5 million around the world, according to Healthline. It's a debilitating disease in which the body's immune system begins to attack its own nervous system, gradually breaking down the protective cover called the myelin sheath, which coats the axons of nerve fibers in the brain and spinal cord.

As this demyelination progresses, patients begin to slowly experience the breakdown of their nervous system – sensation, vision and motor control begin to slowly degenerate, and permanent paralysis can be the end result. It's a horrible sentence.

One well known quirk of the disease is that female sufferers seem to have a reversal of their MS symptoms during the third trimester of pregnancy. This reversal has them feeling great for a couple of months, but then the symptoms reappear with a vengeance after childbirth.

This led researchers to investigate pregnancy hormones. They found that estriol, a form of estrogen, had a significant effect reducing the MS symptoms of lab mice.

But estrogen is a highly compromised treatment. It's been strongly linked to breast and uterine cancers, and has a feminizing effect which makes it particularly unattractive to male sufferers. Which led researchers from UC Riverside and Rockefeller University to start investigating compounds that might produce a similar effect on MS symptoms without the hormonal side effects.

Both teams have zeroed in on indazole chloride, a ligand that stimulates the ERβ estrogen receptors in the body without requiring raised levels of estrogen. And both teams have reported impressive results reversing the progression of MS symptoms in mice. The drug appears to be effective long after the onset of the disease, and seems to be able to stimulate the rebuilding of the myelin sheath, not only in MS cases, but in cases of traumatic brain and spinal cord injury. In simple terms, if the nerves haven't already been totally destroyed, indazole chloride helps rebuild them.

"Our work on mice suggests that its effect is permanent," said Associate Professor Seema K. Tiwari-Woodruff of UC Riverside. "But perhaps more significant, Ind-Cl remyelinates, that is, it makes new sheaths around those axons that have not been lost for good. This means Ind-Cl not only inhibits inflammation but is capable of reducing axon degeneration and restoring neuronal function… Ind-Cl works in two ways: through the immune system in terms of reducing brain and spinal cord inflammation, and directly by remyelinating the axons. This makes it an extremely promising drug."

Seema Tiwari-Woodruff (left) with lab staff members Leonardo Martinez-Torres (center) and ...

We've written before about promising potential MS cures, particularly Dr. Zamboni's CCSVI work, but that proved to be completely ineffective under rigorous scientific testing.

In contrast, the Riverside team expects to go to clinical trial soon. The teams believe the drug can be tweaked to be even more effective, and eventually administered orally.

So, it's promising news for MS sufferers and their families, but there's still an agonizing wait ahead.

Source: UC Riverside and Rockefeller University (PNAS)

 

New method to determine surface properties at the nanoscale

 

 Known properties of a material can radically change at the nanoscale – a tiny scale about 1/1000 of the diameter of a human hair at which scientists have begun building machines that do work.

Engineering researchers at Texas Tech University have developed a method for characterizing the surface properties of materials at different temperatures at the nanoscale.

Knowing properties of materials at different temperatures is important in engineering, said Gregory McKenna, a professor of chemical engineering and the John R. Bradford Endowed Chair in Engineering. For example, the rubber O-ring that failed during the 1986 space shuttle disaster serves at a tragic case study of what can go wrong when decision-makers don't take this into account.

The problem, he said, is known properties of a material can radically change at the nanoscale -- a tiny scale about 1/1000 of the diameter of a human hair at which scientists have begun building machines that do work. McKenna and graduate student Meiyu Zhai looked at several polymers and explosive materials to see how surface properties varied at the nanoscale and how the surface impacts the nanoscale properties.

Their first results on the "multi-curve method" appeared in the peer-reviewed journal, Journal of Polymer Science Part B: Polymer Physics and was highlighted in Advances in Engineering.

"The nanoscale is a funny range of sizes where materials have properties that are not what we expect, even at a step up at the microscale," he said. "We are developing methods to characterize surface properties and relate them to nanoscale behavior using a nanoindenter and other nano-mechanical measurement methods."

In nanoindentation, researchers can investigate both the elastic properties (how materials spring back when pushed) or the viscous properties (how the material flows). The group has found several surprising results: For example, in other work, the team found extremely thin polycarbonate films become liquid-like at the nanoscale, while they are glassy at the macroscopic size scale. Nanoindentation can be used to relate surface properties to this observation.

As machines get smaller and smaller, McKenna said, knowing this information can be invaluable to future engineers.

The nanoindentation project was funded by The Office of Naval Research. The researchers also are funded by the National Science Foundation and the American Chemical Society-Petroleum Research Fund.


Story Source:

The above story is based on materials provided by Texas Tech University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Meiyu Zhai, Gregory B. McKenna. Viscoelastic modeling of nanoindentation experiments: A multicurve method. Journal of Polymer Science Part B: Polymer Physics, 2014; 52 (9): 633 DOI: 10.1002/polb.23470