Latest news with #UniversityofSãoPaulo
Daily Record
21-07-2025
- Health
- Daily Record
Five-year alert to anyone who owns a pair of sunglasses
Sunglasses aren't just a style statement, and forgetting to maintain them could lead to serious health issues People are just learning that sunglasses can, in fact, 'go off', leaving eyes at risk of permanent eye damage. There are a few warning signs that your sunglasses need replacing or repairing - and they can help you dodge these avoidable health problems. Unlike food, sunglasses don't expire on a set date. Instead, people have a window of a few years with their glasses on average before the UV protection starts to degrade to a point where their eyes aren't as protected against the harsh ultraviolet (UV) rays as much. Eyewear manufacturer Beautaste claims that the passage of time itself isn't to blame. Unavoidable things that lead to daily wear and tear, such as scratches, poor storage, and prolonged exposure to UV rays, all combine to make sunglasses less protective over time. Experts claim that a good pair of resistant sunglasses can, on average, last "anywhere from two to five years, sometimes longer." But just how long your favourite sunglasses last depends on how you use, store, and care for them. A 2016 study from the University of São Paulo suggested replacing sunglasses with UV protection every two years. However, this was under the specific condition of constant, direct sunlight exposure (minimum of two hours a day, every day, for 730 straight days) and most people don't wear sunglasses under such extreme conditions - but the guidance proves the damage the sun's rays can do. To get the most life from your lenses, experts suggest using a hard case when not in use. Stay on top of cleaning the lenses with a microfibre cloth and keep them away from heat and direct sunlight when stored. People should also avoid placing them lens-first on hard surfaces to reduce the risk of damage. Sunglasses primarily work by reducing the amount of visible light and harmful UV rays that reach your eyes. They achieve this through a combination of tinting, which absorbs light, and special coatings, like UV filters, that block ultraviolet radiation. Polarised lenses, specifically, reduce glare from reflective surfaces like water or roads, enhancing visibility in bright conditions. This allows wearers to see more clearly in bright conditions, especially in situations where glare is a major issue (such as driving). According to the National Eye Institute, exposure to UV radiation from the sun can lead to damage that can range from short-term conditions like photokeratitis (sunburned eyes) to long-term issues such as cataracts and age-related macular degeneration. When should I consider replacing sunglasses? If you notice scratches, cracks, or other visible damage to the lenses, it's a good time to consider replacement. If you notice your eyes feeling strained or more sensitive to light while wearing your sunglasses, it could be a sign that they are no longer providing adequate UV protection as well. If you're in love with the style of your sunglasses, replacing the lenses themselve can be an option. The safest and most effective way to replace your lenses is by visiting an optician who can select the right lenses for your sunglasses and fit them professionally, ensuring that the lenses are installed correctly and continue to protect your eyes. Some sunglasses come with removable lenses, making it easier to replace them at home. However, not all models allow for this, and some may require special tools. If your sunglasses have this feature, follow the manufacturer's instructions carefully. For people taking this as an opportunity to refresh the style of their sunglasses, experts warn that expensive and designer sunglasses aren't always best for their health. Specsavers claimed that shoppers need to be mindful of "certified UV protection" to keep their eyes safe from damage - and shared this guide of what to look for when picking your next set of shades.
Scientific American
15-07-2025
- Health
- Scientific American
Aging Rates Vary by Country. Politics Might Be Why
Social inequality and weak democratic institutions are linked to faster ageing, as are other environmental features such as high levels of air pollution, finds a study spanning four continents. Education was one of the top factors that protected against faster ageing. The study also showed that ageing is accelerated by less-surprising factors such as high blood pressure and heart disease. But the link to social and political influences could help to explain why rates of ageing vary from country to country, the authors say. 'It's a very important study', says Claudia Kimie Suemoto, a geriatrician at the University of São Paulo in Brazil who was not involved in the work. 'It gives us the global perspective of how these dependent factors shape ageing in different regions of the world.' On supporting science journalism If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. Political polarization and uncertainty mean that 'we are living in a world of despair', and that ages people, says lead author Agustín Ibañez, who directs the Latin American Brain Health Institute in Santiago. 'We don't think about the health impacts that this is going to have in the long run.' The study was published today in Nature Medicine. Age gaps The study included 161,981 participants from 40 countries: 7 in Latin America, 27 in Europe, 4 in Asia and 2 in Africa. Just the process of harmonizing these data sets — such as checking that variables were measured in similar ways in different countries — took about 3 years, says Ibañez. The researchers examined previous research to identify possible factors that hasten or slow ageing and that could be compared across countries. They fed data of these factors into a machine-learning model that predicts a person's chronological age. That allowed them to calculate each person's 'biobehavioural age gap': the difference between their true chronological age and their age as predicted by the model. For example, if you are 50 years old but the model predicts that you are 60 years old, you have a biobehavioural age gap of 10 years. Schooling protects The top medical risk factors for faster ageing were high blood pressure, hearing impairment and heart disease. Other risk factors included unhealthy weight, alcohol consumption, sleep problems, diabetes and impaired vision. The factors that provide the best protection against speedy ageing were education, ability to perform activities of daily living and sound cognitive abilities. Other protective factors included physical activity, good memory and the ability to walk well. Egypt and South Africa had the fastest ageing, whereas European countries showed the slowest ageing, and nations in Asia and Latin America were in the middle. Accelerated ageing was strongly linked to markers of eroding democracy — such as restricted voting rights, unfair elections and restrictions on the freedom of political parties. 'We never expected that,' says Ibañez. Faster ageing was also linked to lower national income levels, exposure to air pollution, social inequality and gender inequality. The researchers had data points up to 4 years apart for 21,631 participants, allowing for comparison over time. In these data sets, a bigger biobehavioural age gap predicted greater declines in both cognition and the ability to perform daily tasks. Toll of stress How physical ageing is linked to a person's socio-economic and political environment is unclear, but Ibañez hypothesizes that the mechanism might be stress's physical effects on the body and brain. 'Inflammation is a huge potential pathway,' he says. One of the limitations of working with data from so many countries, Ibañez says, is that the researchers had to omit many variables, such as smoking, that are known to strongly affect ageing, but were measured in very different ways across countries. Another limitation, Suemoto says, is that 4 years of follow-up data 'is very limited for the ageing process'. She would like to see data points 10 or 20 years apart. Both Suemoto and Ibañez are excited about the possibility that public policy could be tailored to the factors that contribute most to ageing in a specific nation. Intriguingly, the model predicted that some people were biologically younger than their chronological age. Perhaps studying the factors that these people have in common could point to interventions to protect others from premature ageing, Ibañez says.
Yahoo
27-06-2025
- Health
- Yahoo
Heavy Drinkers Face Higher Risk of Brain Lesions And Alzheimer's Markers
Alcohol is notoriously bad for health, and a recent study might add "long-term effects on brain health" to the growing list of ways drinking can cause harm. The research, led by scientists at the University of São Paulo in Brazil, investigated the impact of regular drinking by examining brain autopsy data from 1,781 individuals, correlating findings with their reported drinking habits. After adjusting for sociodemographic and clinical variables, like smoking and physical activity, the team found that the heaviest drinkers had a 133 percent higher risk of developing vascular brain lesions compared to non-drinkers. Those who had been heavy drinkers but since given it up had an 89 percent higher risk, while moderate drinkers had a 60 percent higher risk. Related: Heavy and former heavy drinkers also seemed to have higher odds of other neurological damage than non-drinkers. Heavy drinkers were found to have a 41 percent higher risk of tau protein tangles – a biomarker of Alzheimer's disease – while former heavy drinkers still had a 31 percent higher risk. Heavy drinkers also seemed to die 13 years earlier, on average, than non-drinkers. It's important to note, however, that the study only shows an association – it doesn't confirm that heavy drinking directly causes the kind of brain damage seen. The data was collected as part of Brazil's Biobank for Aging Studies project, which examines the brains of people post-mortem. In this case, the researchers searched for signs of brain tissue injury, including lesions from hyaline arteriolosclerosis and tau tangles from Alzheimer's disease. To determine the participants' drinking habits, their next of kin filled out a detailed questionnaire about what their alcohol consumption was like three months before their death. The researchers divided the cohort into four groups based on how many drinks they consumed per week, with one drink equaling 14 grams of alcohol. They classified 965 people as never-drinkers, 319 as moderate drinkers (seven or fewer drinks per week), 129 as heavy drinkers (eight or more per week), and 368 as former heavy drinkers. "We found heavy drinking is directly linked to signs of injury in the brain, and this can cause long-term effects on brain health, which may impact memory and thinking abilities," says pathophysiologist Alberto Fernando Oliveira Justo from the University of São Paulo. "Understanding these effects is crucial for public health awareness and continuing to implement preventive measures to reduce heavy drinking." Along with the increased risks of brain lesions and tau tangles, the team found that former heavy drinkers were more likely to have a lower brain mass-to-body height ratio, and impaired cognitive abilities as judged by their next of kin during an interview. Strangely though, these links weren't found for moderate or heavy drinkers. The researchers acknowledge the limitations of the study: being a cross-sectional analysis, it can't establish direct causality. They also weren't able to follow patients before death to get more details on their alcohol consumption and other lifestyle factors over time – the duration and changes in their drinking habits couldn't be accounted for. Still, the association adds another concern to the long list of potential health troubles that alcohol consumption could trigger, even in moderation. The stuff is already linked to higher risks of heart troubles, several types of cancer, and slower healing. The research was published in the journal Neurology. Promising New Drug For Weight Loss Works With Just One Monthly Dose Is There Thimerosal in Vaccines, And Is It Safe? Here's What The Science Says Amazonian Scorpion Venom Can Kill Breast Cancer Cells, Scientists Say
The Guardian
26-06-2025
- Science
- The Guardian
‘We are perilously close to the point of no return': climate scientist on Amazon rainforest's future
For more than three decades, Brazilian climate scientist Carlos Nobre has warned that deforestation of the Amazon could push this globally important ecosystem past the point of no return. Working first at Brazil's National Institute for Space Research and more recently at the University of São Paulo, he is a global authority on tropical forests and how they could be restored. In this interview, he explains the triple threat posed by the climate crisis, agribusiness and organised crime. What is the importance of the Amazon? As well as being incredibly beautiful, the world's biggest tropical rainforest is one of the pillars of the global climate system, home to more terrestrial biodiversity than anywhere else on the planet, a major influence on regional monsoon patterns and essential for agricultural production across much of South America. You were the first scientist to warn that it could hit a tipping point. What does that mean? It is a threshold beyond which the rainforest will undergo an irreversible transformation into a degraded savannah with sparse shrubby plant cover and low biodiversity. This change would have dire consequences for local people, regional weather patterns and the global climate. At what level will the Amazon hit a tipping point? We estimate that a tipping point could be reached if deforestation reaches 20-25% or global heating rises to 2.0-2.5C [above preindustrial levels]. What is the situation today? It is very, very serious. Today, 18% of the Amazon has been cleared and the world has warmed by 1.5C and is on course to reach 2.0-2.5C by 2050. How is this being felt now? The rainforest suffered record droughts in 2023 and 2024, when many of the world's biggest rivers were below the lowest point on record. That was the fourth severe drought in two decades, four times more than would have been expected in an undisrupted climate. Every year, the dry season is becoming longer and more arid. Forty-five years ago, the annual dry season in the southern Amazon used to last three to four months and even then there would be some rain. But today, it is four to five weeks longer and there is 20% less rain. If this trend continues, we will reach a point of no return in two or three decades. Once the dry season extends to six months, there is no way to avoid self-degradation. We are perilously close to a point of no return. In some areas, it may have already been passed. In southern Pará and northern Mato Grosso, the minimum rainfall is already less than 40mm per month during the dry season. Aren't those the areas where the most forest has been cleared for cattle ranching and soy plantations? Yes. Livestock grazing is a form of ecological pollution. The areas that have been most degraded by pastures are at, or very close to, a tipping point. That is all of the southern Amazon – more than 2m sq km – from the Atlantic all the way to Bolivia, Colombia and Peru. Scientific studies show degraded pastures recycle only one-third or one-fourth as much water vapour as a forest during the dry season. There is so much water in the Amazonian soil. Trees with deep roots bring it up and release it into the air, mostly through transpiration by the leaves. In this way, forests recycle 4-4.5 litres of water per square metre per day during the dry season. But degraded land, like pastures, recycles only 1-1.5 litres. That helps to explain why the dry seasons are growing one week longer every decade. Why isn't an Amazonian savannah a good idea? It would be less humid and more vulnerable to fire. The tropical forest generally has 20-30% more annual rainfall than tropical savannahs in Venezuela, Colombia, Bolivia and Brazil. The Amazon also has fewer lightning strikes because the clouds are lower than in the savannah. But the most important difference is the fact that a rainforest has a closed canopy so only 4% of solar radiation reaches the forest floor. This means there is always very little radiated energy for the evaporation of the water so the forest floor vegetation and soil are very wet. Historically, this means that lightning strikes only start very small fires that kill only one or two trees but do not spread. In evolutionary terms, this is one reason why there is so much biodiversity in the rainforest; it is resilient to fire. But once it starts to dry and degrade, it is easier to burn. How would an Amazon tipping point affect the global climate? The forest in the south-eastern Amazon has already become a carbon source. This is not just because of emissions from forest fires or deforestation. It is because tree mortality is increasing tremendously. If the Amazon hits a tipping point, our calculations show we are going to lose 50-70% of the forest. That would release between 200 and 250bn tonnes of carbon dioxide between 2050 and 2100, making it completely impossible to limit global warming to 1.5C. Brazil is one of the world's biggest agricultural exporters. How would a tipping point affect global food security? Almost 50% of the water vapour that comes into the region from the Atlantic through trade winds is exported back out of the Amazon on what we call 'flying rivers'. I was the first to calculate the huge volume of these flows: 200,000 cubic metres of water vapour per second. My former PhD student, Prof Marina Hirota, calculated that tropical forests and Indigenous territories account for more than 50% of the rainfall in the Paraná River basin in the far south of Brazil, which is a major food-growing area. These flying rivers also provide water for crops in the Cerrado, Mato Grosso, Mato Grosso do Sul, Goiás, Paraná, Santa Catarina, Rio Grande do Sul, Paraguay, Uruguay, and all that northern Argentina agricultural area. So if we lose the Amazon, we are going to reduce the rainfall there by more than 40%. Then you can forget agricultural production at today's levels. And that would also contribute to converting portions of the tropical savannah south of the Amazon into semi-arid vegetation. What would be the consequences for nature and human health? The devastation of the most biodiverse biome in the world would also affect hundreds of thousands of species and raise the risks of zoonotic diseases crossing the species barrier. For the first time since the Europeans came to the Americas, we are experiencing two epidemics: Oropouche fever, and Mayaro fever. In the future, the degradation of the Amazon forest will lead to more epidemics and even pandemics. How can an Amazonian tipping point be prevented? In 2019, [the American ecologist] Tom Lovejoy and I recommended nature-based solutions, such as large-scale forestry restoration, zero deforestation, the elimination of monocultures, and a new bioeconomy based on social biodiversity. We argued that it is possible to build back a margin of safety through immediate and ambitious reforestation particularly in areas degraded by largely abandoned cattle ranches and croplands. This prompted a lot of research and new thinking. Is the Brazilian government adopting these ideas? Progress fluctuates depending on who is in power. In August 2003-July 2004, we had about 27,000 sq km of deforestation – a huge number. But the first Lula government, with Marina Silva as environment minister, brought the figure down and it reached 4,600 sq km by 2012. Later, during Bolsonaro's government, it went up to 14,000 sq km. And now, with Lula and Marina back, it is fortunately going down again and there are several beautiful new reforestation projects. This is progress, but not enough. Now I'm saying to Marina Silva, 'Let's get to Cop30 with the lowest deforestation in the Amazon ever, less than 4,000 sq km.' Who knows? But anyway, Brazil is working hard. You have warned that criminal activity is a major new risk. Why? Last year, we had a record-breaking number of forest fires in all biomes in tropical South America – from January to November 2024, the Amazon had more than 150,000. Studies by INPE (The Brazilian Space Agency) show something very, very serious is happening. More than 98% of the forest fires were man-made. They were not lightning strikes. This is very worrying. Because even when we are reducing deforestation, organised crime is making it worse. In my opinion, more than 50% of forest fires were arson. All Amazonian countries are trying to reduce deforestation. That is wonderful, but then what to do to combat organised crime? They control a $280bn business – drug trafficking, wildlife trafficking, people trafficking, illegal logging, illegal gold mining, illegal land grabbing. It is all connected. And these gangs are at war with the governments. That's one of the main reasons I'm becoming concerned because I know reducing deforestation is doable, so is forestry restoration. But how to combat organised crime? How have your feelings about this problem changed? I am worried that we are not acting with sufficient urgency. Thirty-five years ago, I thought we had plenty of time to get to zero deforestation and to combat the climate problem. Back then, deforestation was 7% and global warming was a little bit above 0.5C. I was not pessimistic because I felt we could find solutions. At the Rio Earth Summit in 1992, many people were saying that the world should aim for zero emissions by the year 2000. Unfortunately, nobody moved. Emissions continued to rise and they hit another record high last year. We now face a climate emergency. I am very, very concerned. Tipping points – in the Amazon, Antarctic, coral reefs and more – could cause fundamental parts of the Earth system to change dramatically, irreversibly and with devastating effects. In this series, we ask the experts about the latest science – and how it makes them feel. Tomorrow, Louise Sime talks about Antarctic tipping points Read more
Yahoo
26-06-2025
- Health
- Yahoo
Amazonian Scorpion Venom Can Kill Breast Cancer Cells, Scientists Say
Preliminary results presented at the FAPESP Week France health conference suggest the venom from an Amazon rainforest scorpion (Brotheas amazonicus) might be able to help treat breast cancer. An aging global population, as well as greater exposure to pollutants and stressed-out ecosystems, means we are seeing increasing rates of cancer, dementia, and other diseases. So, in the endless search for more treatment options, some researchers are looking in unlikely places – like a scorpion's tail. To speed things up, a group of researchers from Brazil have been inserting potential genes of interest into a 'factory' organism's DNA to create the gene's product. They can then test the resulting proteins, like those in scorpion venom, for various medical uses. "We were able to identify a molecule in the species of this Amazonian scorpion that is similar to that found in the venoms of other scorpions and that acts against breast cancer cells," explains University of São Paulo pharmacologist Eliane Candiani Arantes. Related: Like chemotherapy drugs, the molecule, BamazScplp1, triggers necrosis – the process of cell death – in the breast cancer cells, causing the cells to rupture. It is still very early in investigating this treatment, but using this heterologous expression 'factory' method of creating molecules from genes, the researchers reported that they have also found a molecule that promotes the growth of blood vessels made from snake venom and a blood component from cattle. "This growth factor favors the formation of new vessels… with the possibility of expanding the industrial scale, since it can be obtained through heterologous expression," says Arantes. Heterologous expression can help researchers understand bioactive molecules, explore their functions, and experiment with different mutations by producing large quantities of them inside another organism. In this case, Arantes and colleagues used a species of yeast (Komagataella pastoris) as factories for their proteins of interest. Using techniques like these could help us track down more of nature's hidden treatments, as long as we don't destroy them first. An Early Warning Signal of a 'Silent Killer' Cancer May Hide in Your Poop Your Blood Type Affects Your Risk of an Early Stroke, Study Finds Has Dementia Risk Declined Over Generations? Here's The Science.
