New treatment may reverse celiac disease

Results of a new phase 2 clinical trial using technology developed at Northwestern Medicine show it is possible to induce immune tolerance to gluten in individuals with celiac disease. The findings may pave the way for treated celiac patients to eventually tolerate gluten in their diet.

After treatment with the technology, the patients were able to eat gluten with a substantial reduction in inflammation. The results also show a trend toward protecting patients’ small intestine from gluten exposure.

The findings will be presented as a late-breaking presentation Oct. 22 at the European Gastroenterology Week conference in Barcelona, Spain.

The technology is a biodegradable nanoparticle containing gluten that teaches the immune system the antigen (allergen) is safe. The nanoparticle acts like a Trojan horse, hiding the allergen in a friendly shell, to convince the immune system not to attack it.

Beyond celiac disease, the finding sets the stage for the technology — a nanoparticle containing the antigen triggering the allergy or autoimmune disease — to treat a host of other diseases and allergies including multiple sclerosis, type 1 diabetes, peanut allergy, asthma and more.

The technology was developed in the lab of Stephen Miller, professor of microbiology and immunology at Northwestern University Feinberg School of Medicine, who has spent decades refining the technology.

“This is the first demonstration the technology works in patients,” said Miller, the Judy Gugenheim Research Professor of Microbiology and Immunology. “We have also shown that we can encapsulate myelin into the nanoparticle to induce tolerance to that substance in multiple sclerosis models, or put a protein from pancreatic beta cells to induce tolerance to insulin in type 1 diabetes models.”

When the allergen-loaded nanoparticle is injected into the bloodstream, the immune system isn’t concerned with it, because it sees the particle as innocuous debris. Then the nanoparticle and its hidden cargo are consumed by a macrophage, essentially a vacuum-cleaner cell that clears cellular debris and pathogens from the body.

“The vacuum-cleaner cell presents the allergen or antigen to the immune system in a way that says, ‘No worries, this belongs here,'” Miller said. “The immune system then shuts down its attack on the allergen, and the immune system is reset to normal.”

In the celiac disease trial, the nanoparticle was loaded with gliadin, the major component of dietary gluten, found in cereal grains such as wheat. A week after treatment, the patients were fed gluten for 14 days. Without treatment, celiac patients eating gluten developed marked immune responses to gliadin and damage in their small intestine.

Celiac patients treated with the COUR nanoparticle, CNP-101, showed 90% less immune inflammation response than untreated patients. By stopping the inflammatory response, CNP-101 showed the capacity to protect the intestines from gluten related injury.

There currently is no treatment for celiac disease.

“Doctors can only prescribe gluten avoidance, which is not always effective and carries a heavy social and economic toll for celiac patients,” Miller said.

About 1% of the population has celiac disease, a serious autoimmune disease in which the ingestion of gluten leads to damage in the small intestine. When people with celiac disease eat gluten (a protein found in wheat), their body mounts an immune response that attacks the small intestine.

Autoimmune diseases generally can only be treated with immune suppressants that provide some relief, but undermine the immune system and lead to toxic side-effects. CNP-101 does not suppress the immune system but reverses the course of disease.

“Celiac disease is unlike many other autoimmune disorders because the offending antigen (environmental trigger) is well known — gluten in the diet,” said Dr. Ciaran Kelly, professor of medicine at Harvard Medical School and director of the Celiac Center at Beth Israel Deaconess Medical Center. “This makes celiac disease a perfect condition to address using this exciting nanoparticle induced immune tolerance approach.”

Kelly, who will be presenting the research abstract in Barcelona, has been working with Miller to apply the technology and define the therapeutic approach to treating celiac disease.

The nanotechnology was licensed to COUR Pharmaceuticals Co., a biotech based in Northbrook and co-founded by Miller. COUR developed CNP-101, which was granted Fast Track status from the U.S. Food and Drug Administration, and brought the therapy to patients in collaboration with Takeda Pharmaceuticals. Takeda will announce Tuesday they have acquired an exclusive global license to develop and commercialize this investigational medicine for celiac disease.

“Given the license by Takeda, COUR will focus on clinical programs in peanut allergy and multiple sclerosis in the near term, and broaden even further over time,” said John J. Puisis, president and chief executive officer of COUR.

Miller, who is on the COUR scientific advisory board, is a stock grantee and a paid consultant for the company. Northwestern University has a financial interest in COUR.

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Health24.com | Child support grant: ‘We sometimes go to bed on an empty stomach’

“It’s really hard but I try to make ends meet from my grandson’s grant,” says Nonosisi Maseko (58) from Vosloorus informal settlements in the East Rand. “He is [in] Grade one. I pay school transport R250 per month, and then we buy food from that money. We don’t have any other income in this house.”

According to Maseko, she can afford 5kg maize meal, a 2-litre cooking oil, 10kg of potatoes and a sunlight green bar soap which they use for bathing and laundry. She buys food so that they can eat and doesn’t consider the nutritional value. “What matters is going to bed with a full stomach.” 

Just a block away from Maseko’s house is Ntombizanele Mbuweni. She is a single parent and supports a family of five from one child support grant. “We sometimes go to bed on an empty stomach,” she says. “Especially towards the end of the month.” She points to a container of macaroni. “This is what I buy to sustain ourselves for the month.” 

Are people getting nutritious food?

According to the September 2019 Pietermaritzburg Economic Justice and Dignity Household Affordability Index, the child support grant is set 25% below the food poverty line and 26% below the cost to secure a basic nutritious diet for a small child aged between 10 and 13 years.

The grant is a fixed value and doesn’t increase as a child grows older. The latest food poverty line – released in April 2019 – calculated by Statistics South Africa (Stats SA) is R561 per capita per month. “This refers to the amount of money that an individual will need to afford the minimum required daily energy intake,” says the organisation. 

Yet the Household Affordability Index shows that in September 2019 it cost R569.86 per month to feed a small child aged between 10 and 13 years a basic nutritious diet. Dr Stephen Devereux, co-director of the Centre for Social Protection Institute of Development Studies explains how the cost of living can lead to malnutrition.

“It costs about R600 per month to buy a nutritious balanced diet for a child, so the child support grant is only enough for two-thirds of a healthy diet for the child, if all the grant money is spent only on food for the child,” Devereux explains.

“But in reality, the grant is collected by an adult in the family, usually the child’s mother, and it is spent on many needs – not only food, and on other family members, not only the child,” he says. Devereux says that families that survive on social grants have to ration their consumption of basic needs, including food.

He further explains: “So they often go hungry, especially at the end of the month before the grants are paid. Indicators of malnutrition, such as stunting are higher in poor households than richer households.” 

South Africa’s latest Demographics and Health Survey, which examined more than 11 000 households across the country, found more than a quarter of children under the age of five are stunted – their development and growth is impaired – mostly because of poor nutrition. The survey also found children from poorer families are more likely to be stunted than those from wealthier families. 

Expanding the grant to pregnant women 

Grow Great and other like-minded organisations are advocating strongly for South Africa’s Department of Social Development to introduce a maternity support grant. The provision of a cash grant to poor and at-risk women during pregnancy would be aligned with the aspirations of South Africa’s National Development Plan (NDP).

According Dr Kopano Mabaso, executive director of Grow Great, much of the vulnerability to stunting begins during pregnancy and in the first few years of life, when most of the brain development is happening and when pregnant women and young children need access to nutritious food filled with the micronutrients necessary to build healthy brains.

“South Africa currently does not make provision for any form of income support for poor women in pregnancy, a time of increased financial vulnerability for the majority of South Africa’s women,” Mabaso says. Expanding the child support grant into pregnancy would go a long way in reducing the risk of stunting by enabling women to access the increased nutrition demands pregnancy places on expectant mothers, she argues. 

“[It will also] enable them to attend the eight prescribed antenatal care visits that are critical to ensuring that the pregnant mother and unborn child receive the required clinical care, medication and support during pregnancy.” 

She tells Health-e News that reducing food insecurity in pregnancy would contribute to reduced maternal depression, which research estimates affects a third of pregnant women. It has also been shown to have adverse effects on infant growth, brain development and maternal-infant bonding and attachment.

“The child support grant is successful at reaching large numbers of children and reducing the effects of poverty, but it’s not designed to support maternal nutrition needs nor is it sufficient to support the basic needs of children,” Mabaso says.

South Africa identified expanding social protection into pregnancy as a policy aspiration in the NDP is commendable, she adds, but it’s now time to move from aspiration to action. “We must ensure we protect all children’s right to enjoy a future free from the injustice of nutritional stunting by expanding the child support grant into pregnancy.” 

Is government doing enough?

According to Professor Ebenezer Durojaye, head of the socio-economic rights project at the Dullah Omar Institute at the University of the Western Cape, the levels of malnutrition in South Africa, is an indication that the government is not doing enough.

About 2.5 million young children in the country live below the food poverty line. This means that these children, Durojaye says, live in households where there is insufficient money to cover their basic nutritional needs, putting them at risk of stunting.“

On paper it would seem the government is doing well. But in reality, this is far from the truth, because all these programmes and policies have not translated into a positive impact on the lives of the people,” Durojaye explains.“ Due to poor or ineffective implementation, the right to food remains unrealisable for many South Africans.

It is clear that beyond these [feeding] programmes, government needs to redouble its efforts in ensuring their proper implementation on the ground.” Durojaye says that because there are various government departments handling issues relating to food, there is fragmentation in activities and policies.

Currently, the departments of social development, education, health, rural development and others are involved in implementing the food programmes, which he believes is the reason coordination is sometimes difficult. According to Durojaye, South Africa needs a specific law that deals with the right to food and good nutrition.  This will ensure that families like the Masekos and Mbuwenis are not stranded for food as month-end approaches which leads them into desperate circumstances. 

Mbuweni says she sometimes goes to the nearby grocery store to get expired rolls to feed her children. She steps outside her home and points to a giant nylon sack full of boxes. “I also sell boxes to the nearby scrap yard where I only make not about R70. It depends on how many kilograms it is.

– Health-e News

Image credit: iStock

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Health24.com | When is the best time to exercise?

We all have our favourite times of day to work out. Some prefer to do it as early as possible and get it out of the way. Others prefer to save their exercise for after work to get a clear head and rid themselves of the frustrations of the day.

But experts believe that you can reap extra health benefits if you work out before breakfast.

According to a new study, published in the Journal of Clinical Endocrinology and Metabolism, scientists at the universities of Bath and Birmingham found that you can control your blood sugar levels more effectively when working out before breakfast.

What the research entailed

The study ran for six weeks and involved thirty male participants who were either obese or overweight. According to the news report on the study, results from two intervention groups (who ate breakfast before or after exercise) and one control group (where no lifestyle changes were made) showed that those who exercised before breakfast burned double the amount of fat compared to those who exercised after breakfast.

The reason? The difference is mainly because of lower insulin levels of those who were still in a fasting state before breakfast, meaning that more fuel is utilised from tissue and muscle instead of food.

There were no weight changes in the participants over the six weeks, but researchers maintain that the study results could have a profound effect on health – bodies are better able to respond to insulin and keep blood sugar under control in those who exercise before breakfast. This means that there is less risk for heart disease and diabetes in the future.

Dr Javier Gonzalez of the Department for Health at the University of Bath explained: “Our results suggest that changing the timing of when you eat in relation to when you exercise can bring about profound and positive changes to your overall health.

Muscles more responsive to insulin

“We found that the men in the study who exercised before breakfast burned double the amount of fat compared to the group who exercised after. Importantly, whilst this didn’t have any effect on weight loss, it did dramatically improve their overall health.

“The group who exercised before breakfast increased their ability to respond to insulin, which is all the more remarkable given that both exercise groups lost a similar amount of weight and both gained a similar amount of fitness. The only difference was the timing of the food intake.”

The scientists also found that the muscles of those who exercised before breakfast were more responsive to insulin and showed a greater increase in key protein.

Image credit: iStock

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Matchers and Mismatchers

Sometime during the 90s, I listened to an audio program that explained the differences between matchers and mismatchers.

Matchers are “yes, and” people who see the upsides of an idea more prominently than the downsides. If you share a new idea with them, they’ll see how the idea could work and may offer suggestions for what else you could do to make it even better.

Mismatchers are “wait, but” people who see the downsides of an idea more prominently than the upsides. If you share a new idea with them, they see what could go wrong and may point out the risks and drawbacks.

I’m a matcher. I find it easy to feel optimistic and enthusiastic about a new idea, often thinking about what could go right before I think about what could go wrong.

I’d say that my Mom is a mismatcher. When I’d share my youthful ideas with her, she’d often express skepticism and might point to some of the risks. I think that’s because she herself was raised by parents who lived through the Great Depression and learned the dangers of excessive optimism.

Incubating Ideas

Another lesson I learned from that same audio program was that it’s wise to involve matchers in the early phases of developing an idea. A group of matchers working together will raise the level of excitement and enthusiasm. They’ll help to develop the overall vision. They’ll see the best possible outcomes.

If, however, you bring one or more mismatchers into the early development phase, it’s like throwing a wet blanket on the whole affair. They’ll suck all of the joy and fun out of the process that matchers love, and they’ll think they’re doing everyone a favor by voicing risks and concerns early. Many otherwise viable ideas die early deaths this way. If you have one mismatcher in a room full of matchers, the mismatcher will be the one that everyone else wants to strangle. The matchers will likely regard the mismatcher as obstructing progress and unnecessarily slowing things down.

Mismatchers do have an important role to play, but it’s generally best to bring them in a bit later, after the vision has grown more solid and real to the matchers – when the idea is starting to take on a life of its own and isn’t so vulnerable to collapse. That’s when it’s good to invite someone to poke holes in the idea and to consider what could go wrong. Mismatchers will often notice flaws and risks that matchers overlook.

As a matcher I can confirm that it’s immensely frustrating to involve a mismatcher too early in a creative project. They’re usually well intentioned but don’t see just how much their cautious nature kills momentum and drains enthusiasm. An idea in the incubation stage can be very delicate. Like a newborn baby, it needs to be nurtured first. If you criticize it for its inadequacies right out of the womb, that isn’t going to help. You have to see its potential first.

Becoming More Balanced

Early in business I was overly optimistic about certain deals. I didn’t adequately consider the risks and got burned more than once. If I’d pay more attention to the mismatcher advice at the time, I might have avoided those problem situations. But looking back I don’t feel that it’s so terrible that I went through those bad deals because I learned a lot from them. They helped me to develop more balance. I grew wiser and made smarter decisions afterwards that led to better results.

Over time I began to realize that being a matcher or mismatcher isn’t a permanent condition. These are default ways of thinking, but we don’t have to remain internally stuck in one mode or another. We’re capable of developing both aspects.

When I do creative projects today, I start with matcher mode. I work through the purpose and vision. I get enthusiastic about the results that will be generated. I think about the positive ripples. I get aligned with doing the project. If I share the idea, I prefer to share it with matchers, so they can help me better understand the idea’s potential.

When the idea is a bit more developed, I turn to the practical side. I identify the risks and list them out one by one. I look at the potential downsides. I consider problems that may arise and how to address them.

Matcher mode is faster. Mismatcher mode is slower. When I want to speed up and go faster, I shift into matcher mode. When I feel uncertain about the risks, I downshift into mismatcher mode and work through more details in advance.

Opportunities Include Problems

Consider that if a problem does arise, it’s rarely fatal. Problems almost always lead to learning experiences that make us smarter and more resilient in the long run. The Great Depression may have been a big setback, but most people got through it okay.

While you might get an “I told you so” from a mismatcher who predicted your problems in advance, a good response might be: “Yeah, and look at these other results I got too. It was still worth doing.”

Many problems don’t actually need to be solved. Some problems may simply be regarded as side effects to be accepted. An example would be if we do a program with live call times. Of course some people won’t be able to make the times we choose. We can partially address this by providing recordings. And we can also accept that it’s just the nature of live calls that some people will have scheduling conflicts, and that’s okay.

When you pursue interesting opportunities, problems will arise. Many mismatchers tend to overplay the presence of problems, presuming that each one must be solved before a project can proceed. That may be a wise precaution if you’re building a spacecraft, but for many projects that approach would be overly cautious. In some cases speed of execution is a lot more important than solving every problem that comes up.

When iOS 13 launched about a month ago, people complained that it was buggy. I noticed some bugs too, but on balance I appreciated the new update way more than the bugs annoyed me. I also knew from experience that Apple would eventually push out bug fix updates, and of course that’s been happening. Apple could have waited until a higher standard was met, but for most people iOS 13 was probably good enough to ship, even knowing that there would be problems.

What problems don’t really matter much even if they happen? What problems could you fix later if they happened? What problems would be relatively easy to pre-solve or prevent if just think them through?

Also think about the opportunity side: What opportunities are you delaying or at risk of missing because you’re fussing over potential problems? How will you feel if someone else beats you to the punch because you moved to slowly? Are you really being cautious… or merely sluggish?

Problem or Excuse?

It’s common to see people pointing to problems as roadblocks. How many times have we heard people mention these or similar problems as reasons they can’t move forward in some area?

  • I can’t afford it.
  • I don’t have the time.
  • My family won’t let me.
  • I live with my parents.
  • I don’t have the skills.

If you lean too heavily on mismatcher mode, problems tend to become excuses for inaction. The existence of a problem is all you need to put the brakes on.

If you can lean towards matcher mode though, then problems can be seen as hidden opportunities, including all of the problems listed above. True matchers are advancing in all of these situations.

Finding Your Balance

If you lean too heavily on matcher mode, you may take a lot of action that blows up in your face. Or perhaps you start out overly optimistic, and then you run into unforeseen difficulties and get bogged down. The mismatchers in your life will declare “I told you so” again and again.

If you lean too heavily on mismatcher mode, you’ll talk yourself out of many decent opportunities. Your excessive skepticism will kill ideas before they’ve been nurtured into viable projects. You’ll probably repel most of the matchers in your life, so your social circle will likely be rich in fellow skeptics. You may even consider yourself one of the more balanced ones, wondering why your friends are such downers.

To move interesting goals and projects forward, it helps to develop a balanced approach, either within ourselves or on our teams. A strong matcher or mismatcher can be a valuable asset in the right team position. But I think we can also learn to balance these modes of thinking as individuals, which also helps us to develop more respect for whichever mode of thinking isn’t our dominant one.

A well-balanced matcher can provide drive and energy to maintain the momentum of a project while also staying attuned to potential risks – but without getting bogged down in minor problems.

An unbalanced matcher can be overly impulsive and reckless, thereby adding more problems to a project which only increases the workload. They tend to assume that injecting lots of wild, passionate, yet chaotic energy into the mix is helpful, but of course it often isn’t.

A well-balanced mismatcher can identify problems and help develop solutions and contingency plans, contributing to the advancement and refinement of the project.

An unbalanced mismatcher tends to be overly skeptical or cynical and merely adds a critical voice without offering solutions or intelligent risk assessment. They tend to assume that pointing out problems and voicing concerns will be valued by others, but of course it often isn’t.

When you realize you’re out of balance, just as I did, it takes some effort to practice a different mode of thinking, but it can be done. Getting burned enough times or missing enough opportunities can be good motivation to make changes. But another thing that helps is just gaining experience.

I find that thinking about these modes consciously really helps me to achieve more balance, so I hope that becoming more aware of these modes is useful for you as well. Sometimes I’ll switch back and forth multiple times at different phases of a project. There are matcher and mismatcher modes for development, for launching, for marketing, for serving customers, and so on.

And remember these final rules of thumb:

  • Shift into matcher mode when you want to go faster (or if you sense that progress has been too slow or nonexistent).
  • Shift into mismatcher mode when you want to be more cautious (or if you sense that progress has been too chaotic, unstable, or stressful).

The key is to apply these modes of thinking at different times, so they don’t interfere with each other.

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Health24.com | ‘I felt a pea-sized lump next to my right nipple – but I ignored it’

Male breast cancer survivor, Robert Were (63) says he never thought he would be diagnosed with breast cancer because it has been branded as a cancer affecting only women.

According to Breast Health Foundation, “In North America there seems to be an increasing incidence especially amongst black males, with about a thousand cases being diagnosed per year. We don’t know how common it is in South Africa, but we think between 1–3% of all breast cancers happen in men.”

Due to lack of awareness, most men don’t know that they can be diagnosed and ignore the early warning signs.

The first reaction is to ignore

Despite having a lump on his chest, Were chose to ignore it hoping it will go away. “Whilst bathing one evening in 2006, I felt a pea-sized lump next to my right nipple. I called my wife and asked her to look at it; she agreed that something was not right and said I should see a doctor but my male stubbornness kicked in immediately. You know what I mean; we men think we know much better than any doctor and I informed my wife that it was nothing and that I was fine,” says Were.

In males, breast cancer is usually detected as a hard-lump underneath the nipple and areola. Men also have a higher mortality rate than women because they are less likely to believe that a lump can be a sign of cancer so they take their time to seek treatment. Men tend to delay going to the doctor until they have more severe symptoms, such as bleeding from the nipple and changes to the skin covering the breast such as dimpling, puckering, redness and scaling.

Such was the case with Were. It took him almost two years to get a diagnosis, despite having been aware of the lump on his chest.

“By the end of 2008, the lump had not only grown but was also oozing slightly. On December 28, 2008 I went for an appointment to see a doctor. She insisted on seeing the lump. One look at it and the doctor said, ‘That’s cancer’. She didn’t touch it or even look closely, so I was angry with her. Who gave her the right to say I had cancer?” says Were.

Male breast cancer can happen to anyone but the chance are increased in men between the ages 60 and 70.

Despite having been officially diagnosed by a medical doctor, and experiencing symptoms, Were says that he continued to live in denial. “The fact that I had an inverted nipple and the orange peel symptoms meant nothing. Again, I tried a feeble ‘it’s nothing’ – only this time no one was listening to me. The doctor gave me a referral to the surgeon, and made the appointment for me to go. There seemed no way out of this for me. Here is this lady doctor telling me, a man, that I have breast cancer. How ridiculous is that, I don’t even have ‘breasts’,” he says.

Acceptance and creating awareness

After he went for an operation to remove the lump, he had accepted that he had cancer. “When I came around after the operation, I felt the drain and then I felt a second drain. I knew then that it had been cancer and an absolute calm came over me. I had no pain and tried to feel if they had in fact done a mastectomy. I was told that the cancer was at stage three,” he says. He believes that one of the main reasons why most men don’t want to go for check-ups of any disease is that they fear being sick.

“There is nothing worse than a sick male, believe me. Fourteen days after my first round of chemo, I woke up and saw my pillow full of hair, and took out fistfuls of hair as I washed it. I then decided to cut off the hair that was left. Seeing myself with no hair was, to say the least, frightening. Who was this ugly dude in the mirror, coupled with this dent in my chest and this scar line through its centre was horrid to look at. I had been stripped of my dignity in just a few short weeks,” he says.

Almost 10 years later, Were says he always encourages other men to go for regular check-ups for various cancers. “Despite all this, I believe that my journey with cancer has been one of the greatest blessings in my life. I have since completed all my treatments and I am in my tenth year of being cancer free. This is only down to the grace of the Almighty God. We need to remember that we are all individuals and the way we respond to treatment is different in each person. We all need to form our own mechanisms to fight; for me it was to keep my brain busy and to trust in my Heavenly Father,” he says.

Global numbers

According to World Health Organization (WHO) International Agency for Research on Cancer, one in five men and one in six women worldwide develop cancer during their lifetime, and one in eight men and one in 11 women die from it. Worldwide, the total number of people who are alive within five years of a cancer diagnosis, called the prevalence, is estimated to be 43.8 million. The increasing cancer burden is due to several factors including population growth, ageing, as well as the changing prevalence of certain causes of cancer linked to social and economic development.

– Health-e News

Image credit: iStock

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Gimme six! Researchers discover aye-aye’s extra finger

The world’s weirdest little primate has gotten even weirder, thanks to the discovery of a tiny extra digit. A study led by researchers from North Carolina State University has found that aye-ayes possess small “pseudothumbs” — complete with their own fingerprints — that may help them grip objects and branches as they move through trees. This is the first accessory digit ever found in a primate.

Aye-ayes are unusual animals from the get-go: these extremely rare lemurs are known for their constantly growing incisors, large ears, and strange hands — particularly for the slender, elongated middle fingers that they use for locating and spearing grubs inside trees.

“The aye-aye has the craziest hand of any primate,” says Adam Hartstone-Rose, associate professor of biological sciences at NC State and lead author of a paper describing the work. “Their fingers have evolved to be extremely specialized — so specialized, in fact, that they aren’t much help when it comes to moving through trees. When you watch them move, it looks like a strange lemur walking on spiders.”

Hartstone-Rose and NC State post-doctoral researcher Edwin Dickinson were studying the tendons that lead to the aye-aye’s unusual hands when they noticed that one of the tendons branched off toward a small structure on the wrist. Using traditional dissection digital imaging techniques on six aye-ayes, the researchers found that the structure in question is composed of both bone and cartilage, and has musculature that allows it to move in three directions — much the same way that human thumbs move.

“Using these digital techniques allows us to visualize these structures in three dimensions, and to understand the organization of the muscles which provide movement to the digit,” says Dickinson, who built the digital model of the anatomy and is co-first author of the paper.

“The pseudothumb is definitely more than just a nub,” Hartstone-Rose says. “It has both a bone and cartilaginous extension and three distinct muscles that move it. The pseudothumb can wriggle in space and exert an amount of force equivalent to almost half the aye-aye’s body weight. So it would be quite useful for gripping.”

The team examined aye-aye specimens from both sexes, ranging in age from juvenile to adult, and found the same structure in both the left and right hands of each one.

According to Hartstone-Rose and Dickinson, the aye-aye may have developed the pseudothumb to compensate for its other, overspecialized fingers.

“Other species, like the panda bear, have developed the same extra digit to aid in gripping because the standard bear paw is too generalized to allow the dexterity necessary for grasping,” Hartstone-Rose says. “And moles and some extinct swimming reptiles have added extra digits to widen the hand for more efficient digging or swimming. In this case, the aye-aye’s hand is so specialized for foraging an extra digit for mobility became necessary.

“Some other primate species have reduced digits to aid in locomotion. The aye-aye is the first primate to dial digits up in the hand rather than dial them down. And it’s amazing that it’s been there the whole time, in this strangest of all primates, but no one has noticed it until now.”

Story Source:

Materials provided by North Carolina State University. Note: Content may be edited for style and length.

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