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Chilean scientists discover a potential way to diagnose Alzheimer’s through the eyes


A recent study published in the journal Scientific Reports, by Nature, reveals a technique applied with mathematical modeling that could detect the presence of neurodegenerative diseases, such as Alzheimer’s, before their most characteristic symptoms appear.

Both Alzheimer’s, as well as other neurodegenerative diseases, are very difficult to diagnose early. However, a group of Chilean researchers conducted a study that could provide an innovative way to investigate this disease through the eyes. Especially, through the electrical signals generated in the retina before different visual stimuli.

The article was recently published in the journal Nature’s Scientific Reports. There, this group of health professionals and engineers, made up of Joaquín Araya-Arriagada; Sebastian Garay; Cristobal Rojas; Claudia Duran-Aniotz, Adrian Palacios; Max Chacón and Leonel Medina, managed to demonstrate through mathematical modeling a relationship between the function of electrical activity and the early presence of this type of dementia that affects about 35 million people on the planet, according to the World Health Organization. Health.

“What we do in this study is to mathematically model a concept that exists in physiology, called “complexity”. The idea is that the complexity of a brain decreases, either with age or with disease. And, on the contrary, as long as it works well, high rates of complexity will be shown”, says Cristóbal Rojas, one of the researchers of this study and professor at the Institute of Mathematical and Computational Engineering of the Pontifical Catholic University of Chile (IMC).

According to Rojas, who is also a doctor in Mathematics and Computer Science, “complexity” is difficult to capture or measure mathematically. However, there are some signs or traces left by this complexity that can be measured. “What we do is use or adapt a tool, based on the notion of entropy, which does not precisely measure this complexity, but rather measures the level of disorder in general. There are multiple parts that come together at different scales to determine this complex behavior,” he explains.

In this context, in this particular work it was possible to measure these parameters for two groups of rats: one genetically modified to develop the disease, and the other half healthy. Both groups were shown different visual stimuli, such as lights at different intensities and a first-person video walking through a forest, in order to measure the electrical activity in the retina. “That electrical activity, over time, draws a pattern that we apply an entropy measurement to that allows us to estimate the complexity levels,” Rojas details.

This complexity, in itself, is the way in which the electrical communication between neurons is organized. Then, and as detailed by the academic, when making this visual stimulus the neuron reacts and works in a certain way, they connect and emit electrical signals with each other.

Alzheimer’s through the eyes
“What we observed is that mice, both older and those with Alzheimer’s disease, show a lower degree of complexity than young, healthy mice. So, at least we were able to find evidence that this tool could be used to distinguish these two groups and make an early diagnosis”, describes the researcher of this study. This, according to Rojas, is evidence of a potential method to diagnose the presence of this type of dementia early, before its most characteristic symptoms appear.

Cristóbal Rojas, one of the researchers of this study and professor at the Institute of Mathematical and Computational Engineering of the Catholic University (IMC).

Cristóbal Rojas, one of the researchers of this study and professor at the Institute of Mathematical and Computational Engineering of the Catholic University (IMC).
Alzheimer’s, which accounts for nearly 70% of all types of dementia, develops and worsens over time, with symptoms appearing several years after neurodegeneration began to occur. “This study detects the decrease in complexity that would appear early. A little after the retina begins to have the presence of the ‘Tau protein’, which manifests itself when Alzheimer’s begins to develop. It is not a prediction of the disease, but rather it is a much earlier diagnosis than can be analyzed through the symptoms”, adds the researcher from the Catholic University.

There are still many studies to be carried out to apply this type of procedure in humans, explains Cristóbal Rojas. To have a good projection in this research, humans would have to be in front of these visual stimuli for a certain time, in order to have a pattern of electrical activity in the retina of people. “In this way, the ranges considered as “normal” or sick, at a certain age, could be established. But for that, it is necessary to understand well the evolution of the pattern of complexity over time”, concludes the Chilean scientist.

Science discovers the impact of quarantine on aging


Scientists from the Moscow State Psychological and Pedagogical University (MSUPE) studied the impact of quarantine on the biopsychological age of the disabled.

It was established that the majority of those who went to work after confinement feel subjectively younger than a year ago, but the biological rhythm of aging increased. The results of the research were published in the journal Modern Foreign Psychology.

MSUPE scientists have long studied the biopsychological age of adults:
the general characteristic of the state of an individual,
your somatic and psychological health,
the correspondence of personal and physiological characteristics to age norms.

The concept of biopsychological age can be described with the use of two scales: biological age and psychological age.
According to experts, the first study was conducted in 2019; the second in 2020 (after about six months of quarantine). The factors that cause stress were established: the illness itself, post-traumatic stress and the factors of quarantine (social isolation, changes in diet, a reduction in physical activity and anxiety). The research included workers over 35 years of age, retirees who work and who do not work with chronic diseases.

To analyze psychological age, the scientists used the “method of independent determination of psychological age”: the participants in the trial determined their age using a 100-point scale; and the “relative psychological aging index” to compare the psychological and actual age of the trial participants. Negative figures show that an individual feels that his age is younger than the real one.
“The research highlighted that, after about six months of the quarantine, the majority of the respondents who work subjectively felt that they are younger than in reality and younger than a year ago, before the quarantine,” says the professor Head of the Department of Scientific Foundations of Extreme Psychology of the Faculty of Extreme Psychology of the MSUPE, Tatiana Beriózina.
According to her, women began to feel younger by an average of 3.3 years (adults) and 7.2 years (retired), and men, by 6.8 years (adults) and 4.7 years ( retired).

The indicator of relative biological aging (the comparison of biological age and proper biological age) made it possible to assess the extent to which an individual is older than he should be, according to established norms. To measure biological age, the researchers used the indicators of various body systems: blood pressure, stopping of breathing, after inspiration, maintenance of static balance in the left foot with eyes closed, weight, subjective assessment of The diseases.
“It is curious that the biological age of retirees with chronic diseases has not changed, while the biological age of people who work increased more than a year, as would happen in the normal aging process”, highlights Tatiana Beriózina.

According to the scientists, the impact of confinement on the somatic health indicators of individuals was diverse. The weight of women did not change during the quarantine. The assessment of their health status by men and women of all groups remained at the same level as well. Several health indicators even improved during the quarantine: pulse pressure indicators were normalized in adult women who work and retired women with chronic diseases; systolic blood pressure normalized in men.
“Quarantine had a strong negative impact on people’s physical development. They reduced their physical activity or stopped exercising and, in general, began to move less, so the characteristics of the body’s physical preparation worsened drastically. In all of them the groups decreased the time of maintaining static equilibrium, the ability of an individual to stand on one foot with their eyes closed, “says Beriózina.

Researchers noted that balance maintenance time for adult women was reduced by 26% and for retired women with chronic illnesses, by 13%. These indicators were also reduced in the groups of men: 37% in the group of adults who work and the respective trend was noted in the group of retired people who work. In addition, in the group of men, the time to stop breathing after inspiration was reduced: 4% in the group of retired people who do not work with chronic diseases, and the respective trend was noted in the other groups.
The research was carried out with financial support from the Russian Scientific Foundation, project No. 19-18-00058.

Scientists identify the key to extending our human life dramatically



THE IDEA THAT WE CAN EXTEND OUR LIVES far beyond a century conjures up images of humans stored in cryogenic chambers and decapitated heads preserved in jars, kept alive by humming machines – in other words, science fiction.

But if a new study published Tuesday in the journal Nature Communications is anything to go through, such a dramatically prolonged life is not a fantasy at all. The study, which combines data from blood tests and information on physical exercise to identify a new measure of “biological age.” The findings suggest that there is an aspect of human longevity that may be crucial if we are ever to reach our full potential. Contrary to intuition, it has nothing to do with illness or a lifestyle choice.

“What we’re saying here is that the strategy of reducing frailty, so reducing the burden of disease, has only an incremental ability to improve your life expectancy,” Peter Fedichev tells Inverse. Fedichev is the lead author of the study and a researcher at the Moscow Institute of Physics and Technology. He is also a co-founder of the longevity startup Gero.

According to Fedichev and his team, humanity can do better than simply treat disease. In fact, if these results are validated, our species could begin to live for decades even longer than the maximum lifespan they determined: 150 years.

HERE’S THE VIEW – The study identifies patterns of aging and morbidity to extract the maximum possible “biological age” from humans. To do this, the researchers collected blood sample analysis data from 544,398 participants and combined it with Fitbit data from a separate, smaller subset of people. They then used the data to predict the onset of various diseases and to determine patterns in how people’s “biological age” seemed to change over time.

The “biological age” is essentially the age of the cells in your body, rather than their chronological age. To increase life expectancy, it is necessary to reduce biological age compared to chronological age. Various lifestyle choices can make a difference. If you start smoking, start a new exercise regimen, or even move to a more rural area, your biological age can decrease and increase over time. It does not remain constant.

As age and a more dynamic factor called “DOSI” increases, our ability to bounce back from disturbances deteriorates. Gero PTE. LTD.

As age increases and a more dynamic factor called “DOSI” increases, our ability to recover from disturbances deteriorates. Gero PTE. LIMITED.
In the new study, the researchers found that one factor appeared to drive individual fluctuations in biological age, a value the researchers call the “dynamic quantitative indicator of the body’s state.” To understand this measure, the researchers explain it like this: As you age, your rate of recovery from different stresses – be it illness, lack of sleep, or even hard exercise – slows down. In other words, it takes longer and longer to return to its baseline level of resilience. Therefore, people’s resistance to stress is the key to determining their longevity.

“If you don’t focus on loss of resilience, any medical intervention will fail,” the researchers write in the study.

WHY IT MATTERS: If medicine advances to the point where the diseases of aging can be cured, then researchers estimate that humans can age even longer than the maximum life expectancy they determined without addressing resilience: 120-150 years . Beyond that, our resilience deteriorates beyond the point of no return. Even the healthiest people who live longer and resist the onset of chronic diseases cannot expect to live beyond this age, they say, because their ability to recover would have been completely exhausted.

Now, 120 years of life is nothing to sniff out. But the researchers argue that if we find a way to address resilience rather than just the other issues that come with age that, to use Fedichev’s word, “disintegrate” us as organisms, then we could theoretically halt the aging process.

Fedichev tells Inverse a story he heard from another longevity researcher, Nil Brazilei, about a woman who was 105 years old and had smoked her entire life.

“All the other doctors would go to see her and ask, ‘Don’t you know that smoking is bad? Didn’t the doctors tell you? ‘”, He relates. She apparently replied, “Some of them have, and they’re all dead now.”

In other words, on an individual level, lifestyle factors may not always explain why we or do not live to old age. But resilience could.

WHAT’S NEXT: Fedichev and his co-authors don’t want to settle for the incremental increases in average life expectancy that can come from improvements in health. We already know, Fedichev says, that on average, people live longer if they have a good diet, exercise regularly, can avoid illness, and have high socioeconomic status (an important factor that is often overlooked). But people who live to extraordinary ages can also carry certain genes that predispose them to longevity.

And maybe, Fedichev says, those genes affect resilience.

If we can increase resilience, then we could extend life beyond the maximum that Fedichev and his colleagues identify here.

As part of their work at Gero, Fedichev and a team led by engineer Tim Pyrkov created an application, called GeroSense, that can calculate biological age using data provided by users. They hope to use the information they collect to measure resilience and ultimately find a solution to stop aging.

Among the factors they want to take a closer look at:

Lifestyle choices
Subsistence allowance
Genetic markers
“What are the most nutritional and medical interventions and, finally, what are the genetic makeup variables that may or may not influence resilience?” Fedichev asks. “Because that would be the Holy Grail of aging.”

This, he says, could come very soon. “We should be able to use a drug that works against the same pathway … or do clinical trials or maybe develop something that is completely new and slow down human aging,” he says.

“I think it’s very reasonable to believe that [we will find it], in five years or more, with this resilience modifier.”

Summary: We investigated the dynamic properties of body state fluctuations along individual aging trajectories in a large longitudinal database of CBC measurements from a consumer diagnostic laboratory. To simplify the analysis, we use a linear logarithmic mortality estimate from the CBC variables as a single quantitative measure of the aging process, hereinafter referred to as the dynamic organism state indicator (DOSI). We observed that the widening of the DOSI distribution of the age-dependent population could be explained by a progressive loss of physiological resilience measured by the time of DOSI autocorrelation. Extrapolation of this trend suggested that DOSI recovery time and variance would diverge simultaneously at a critical point of 120 to 150 years of age, corresponding to a complete loss of resilience. The observation was immediately confirmed by independent analysis of the correlation properties of fluctuations in intraday physical activity levels collected by wearable devices. We conclude that criticality resulting in the end of life is an intrinsic biological property of an organism that is independent of stressors and signifies a fundamental or absolute limit of human life expectancy.

Blind man has partially restored sight after 40 years

A blind man has had his vision partially restored thanks to optogenetic therapy and protective glasses, the first successful case of such therapy in humans.

The researchers treated a 58-year-old man who for 40 years suffered from retinitis pigmentosa, a neurodegenerative eye disease in which the loss of photoreceptors can lead to complete blindness.

Retinitis pigmentosa changes the way the retina responds to light, making vision difficult, and people with the condition slowly lose their vision over time, according to the American Academy of Ophthalmology.

The scientists used a form of gene therapy to reprogram cells in the retina of the eye, injecting them with a viral vector and making them sensitive to light. “In optogenetic therapy … we create an artificial photosensitive layer on this blind retina,” explained researcher Botond Roska, a professor at the faculty of science at the University of Basel, at a news conference.

Months after the injection, the researchers fitted the patient with glasses designed that detect changes in light intensity and project corresponding light pulses onto the retina of the eye to activate the treated cells.

Although the patient was unable to recognize faces or read after treatment, he was able to perceive, locate, count and touch objects using only his treated eye while wearing the glasses, the researchers said in a study published Monday in the journal Nature Medicine.

Before treatment, the patient could not see anything with the glasses. But months after the injection, the man was able to see the white stripes in a crosswalk, detect objects such as a plate, cup or telephone, and identify furniture in a room or a door in a hallway when wearing the glasses.

“Initially the patient couldn’t see anything with the system, obviously this must have been quite frustrating. And then spontaneously he started to get very excited, reporting that he could see the white stripes across the street, ”José-Alain Sahel, professor of ophthalmology at the University of Pittsburgh School of Medicine and the Vision Institute in Paris. instructions.

The scientists also found that visual behavior corresponded to man’s brain activity. The man was the first patient in the first cohort of the study to receive adequate training before the coronavirus pandemic interrupted the investigation.

“An important milestone”
“Retinitis pigmentosa is one of the most common causes of blindness in young people and is the result of the loss of light-sensitive photoreceptor cells in the retina at the back of the eye,” Robert MacLaren, professor of ophthalmology at the Oxford University. he told the Science Media Center in London.

“In this trial, the researchers used gene therapy to reprogram other cells in the retina to make them sensitive to light and thus restore some degree of vision. This is an important milestone and new refinements will undoubtedly make optogenetic therapy a viable option for many patients in the future, ”added MacLaren, who was not associated with the study.

James Bainbridge, professor of retinal studies at University College London, said the technology “could help people whose eyesight is severely impaired.”

“It is a high quality study. It is carried out and carefully controlled. The findings are based on laboratory tests on a single person. More work will be needed to find out if the technology can be expected to provide useful insight, ”Bainbridge, who was not involved in the research, told the Science Media Center.

500 million people have diabetes. But most don’t know


Nearly 500 million people have diabetes, but most are not receiving proper treatment, and more than half have yet to be formally diagnosed with the disease, according to new global research.

Many people simply do not know that they have a condition that is relatively easy and inexpensive to treat, and that, if left untreated, it will shorten their lives, destroy their hearts, blow off an artery in their brain, destroy their nerves, and blind them. . or have their legs cut off.

The big picture is that diabetes worldwide has more than quadrupled since 1980, a growth rate that appears to have left doctors and patients with their feet on the ground.

The study findings have been provided to the World Health Organization, “which is developing efforts to expand the provision of evidence-based diabetes care globally as part of an initiative known as the Global Diabetes Compact.”

What is the breakdown of the study?
The study was led by physicians from the University of Michigan and Brigham and Women’s Hospital.

It is based on standardized household survey data, “to allow apple-to-apple comparisons across countries and regions.”

The authors analyzed data from surveys, examinations and tests of more than 680,000 people between the ages of 25 and 64 conducted around the world in recent years.

More than 37,000 had diabetes; More than half of them had yet to be formally diagnosed, but they did have a key biomarker of elevated blood sugar levels.

Most were not receiving “the comprehensive package of care” (low-cost medications to lower blood sugar, blood pressure and cholesterol, and advice on diet, exercise and weight) that could make their lives healthier, longer and more productive.

Only one in 10 people with diabetes in the low- and middle-income countries studied received this comprehensive care.

Nations in the Pacific Oceania region had the highest prevalence of diabetes, both diagnosed and undiagnosed, but the lowest rates of diabetes-related care.

But bad care was not strictly a poor country problem.

The Latin America and the Caribbean region ranked second after Oceania in the prevalence of diabetes, but had much higher levels of care.

The authors note that high-income countries like the United States do not consistently provide evidence-based care to people with diabetes.

Australians take away food
Being overweight or obese is the predominant gateway to developing type 2 diabetes, especially once you are over 45 years old.

About two-thirds of adults (and one-quarter of children) are already classified as obese or overweight.

According to Diabetes Australia, 280 Australians develop diabetes every day. That’s one person every five minutes.

About 1.8 million Australians have diabetes. This includes all types of diagnosed diabetes (1.3 million known and recorded), as well as silent and undiagnosed type 2 diabetes (up to an estimated 500,000).

Both types of diabetes have some of the same telltale warning signs.

Many people with type 2 diabetes have no symptoms. Because type 2 diabetes is commonly (but not always) diagnosed at a later age, the signs are sometimes dismissed as part of “aging.”

In some cases, when type 2 diabetes is diagnosed, complications from diabetes may already be present.

Symptoms include …
Being excessively thirsty
Passing more urine
Sudden weight loss
Feeling tired and lethargic
Always feeling hungry
Having cuts that heal slowly
Itching, skin infections
Blurry vision
Feeling dizzy
Leg cramps
Tingling in the feet and fingers, also known as peripheral neuropathy.

Treatment is more than just taking a pill
Most people are initially prescribed metformin in pill form to control blood sugar levels and regulate the liver.

It is a very good drug, but its effectiveness may start to wane after five years.

Many people just take this pill and think that everything will be fine.

When first diagnosed, it can take several weeks for the condition to stabilize, at which point you will be referred to a nurse or diabetes counselor who is usually assigned to a pharmacist one or two days a week.

This is the person who will show you what you can eat and how much, and will serve as a cheerleader for you to change your habits.

Losing weight, improving your blood pressure, bringing your cholesterol to a healthy level, exercising regularly, drinking more water – all the boring things you always hear about.

You also need to have your eyes checked once a year and your feet checked for healthy blood flow.