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Tag: University of Copenhagen

  • AI discovers formula for anticipating giant waves.

    AI discovers formula for anticipating giant waves.

    Newswise — Long considered myth, freakishly large rogue waves are very real and can split apart ships and even damage oil rigs. Using 700 years’ worth of wave data from more than a billion waves, scientists at the University of Copenhagen and University of Victoria have used artificial intelligence to find a formula for how to predict the occurrence of these maritime monsters. The new knowledge can make shipping safer.

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    Stories about monster waves, called rogue waves, have been the lore of sailors for centuries. But when a 26-metre-high rogue wave slammed into the Norwegian oil platform Draupner in 1995, digital instruments were there to capture and measure the North Sea monster. It was the first time that a rogue had been measured and provided scientific evidence that abnormal ocean waves really do exist.

    Since then, these extreme waves have been the subject of much study. And now, researchers from the University of Copenhagen’s Niels Bohr Institute have used AI methods to discover a mathematical model that provides a recipe for how – and not least when – rogue waves can occur.

    With the help of enormous amounts of big data about ocean movements, researchers can predict the likelihood of being struck by a monster wave at sea at any given time.

    “Basically, it is just very bad luck when one of these giant waves hits. They are caused by a combination of many factors that, until now, have not been combined into a single risk estimate. In the study, we mapped the causal variables that create rogue waves and used artificial intelligence to gather them in a model which can calculate the probability of rogue wave formation,” says Dion Häfner.

    Häfner is a former PhD student at the Niels Bohr Institute and first author of the scientific study, which has just been published in the prestigious journal Proceedings of the National Academy of Sciences (PNAS). 

    Rogue waves happen every day

    In their model, the researchers combined available data on ocean movements and the sea state, as well as water depths and bathymetric information. Most importantly, wave data was collected from buoys in 158 different locations around US coasts and overseas territories that collect data 24 hours a day. When combined, this data – from more than a billion waves – contains 700 years’ worth of wave height and sea state information.

    The researchers analyzed the many types of data to find the causes of rogue waves, defined as being waves that are at least twice as high as the surrounding waves – including extreme rogue waves that can be over 20 meters high. With machine learning, they transformed it all into an algorithm that was then applied to their dataset.

    “Our analysis demonstrates that abnormal waves occur all the time. In fact, we registered 100,000 waves in our dataset that can be defined as rogue waves. This is equivalent around 1 monster wave occurring every day at any random location in the ocean. However, they aren’t all monster waves of extreme size,” explains Johannes Gemmrich, the study’s second author.

    Artificial intelligence as a scientist

    In the study, the researchers were helped by artificial intelligence. They used several AI methods, including symbolic regression which gives an equation as output, rather than just returning a single prediction as traditional AI methods do.

    By examining more than 1 billion waves, the researchers’ algorithm has analyzed its own way into finding the causes of rogue waves and condensed it into equation that describes the recipe for a rogue wave. The AI learns the causality of the problem and communicates that causality to humans in the form of an equation that researchers can analyze and incorporate into their future research.

    “Over decades, Tycho Brahe collected astronomical observations from which Kepler, with lots of trial and error, was able to extract Kepler’s Laws. Dion used machines to do with waves what Kepler did with planets. For me, it is still shocking that something like this is possible,” says Markus Jochum.

    Phenomenon known since the 1700s

    The new study also breaks with the common perception of what causes rogue waves. Until now, it was believed that the most common cause of a rogue wave was when one wave briefly combined with another and stole its energy, causing one big wave to move on.

    However, the researchers establish that the most dominant factor in the materialization of these freak waves is what is known as “linear superposition”. The phenomenon, known about since the 1700s, occurs when two wave systems cross over each other and reinforce one another for a brief period of time.

    “If two wave systems meet at sea in a way that increases the chance to generate high crests followed by deep troughs, the risk of extremely large waves arises. This is knowledge that has been around for 300 years and which we are now supporting with data,” says Dion Häfner. 

    Safer shipping

    The researchers’ algorithm is good news for the shipping industry, which at any given time has roughly 50,000 cargo ships sailing around the planet. Indeed, with the help of the algorithm, it will be possible to predict when this “perfect” combination of factors is present to elevate the risk of a monster wave that could pose a danger for anyone at sea.

    “As shipping companies plan their routes well in advance, they can use our algorithm to get a risk assessment of whether there is a chance of encountering dangerous rogue waves along the way. Based on this, they can choose alternative routes,” says Dion Häfner.

    Both the algorithm and research are publicly available, as are the weather and wave data deployed by the researchers. Therefore, Dion Häfner says that interested parties, such as public authorities and weather services, can easily begin calculating the probability of rogue waves. And unlike many other models created using artificial intelligence, all of the intermediate calculations in the researchers’ algorithm are transparent.

    “AI and machine learning are typically black boxes that don’t increase human understanding. But in this study, Dion used AI methods to transform an enormous database of wave observations into a new equation for the probability of rogue waves, which can be easily understood by people and related to the laws of physics,” concludes Professor Markus Jochum, Dion’s thesis supervisor and co-author.

    Links:

    Read the scientific paper “Machine-Guided Discovery of a Real-World Rogue Wave Model” published in PNAS: https://www.pnas.org/cgi/doi/10.1073/pnas.2306275120

    Read the Wikipedia-list of registered rogue waves: https://en.wikipedia.org/wiki/List_of_rogue_waves

    Dion Häfner’s research continues at Pasteur Labs.

    University of Copenhagen, Faculty of Science

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  • New Method Simplifies Identification of Right Treatment for Tabooed Disease Affecting Thousands

    New Method Simplifies Identification of Right Treatment for Tabooed Disease Affecting Thousands

    Newswise — Most people have at some point in their life suffered an intestinal infection or food poisoning forcing them to stay close to the bathroom. It is very uncomfortable. Most of the time, though, it passes quickly.

    But around 60,000-100,000 Danes suffer from a form of chronic diarrhoea called bile acid malabsorption or bile acid diarrhoea.

    It is a chronic condition characterised by frequent and sudden diarrhoea more than 10 times a day. Even though the disease is not life-threatening, it can seriously affect the patient’s everyday life, especially their social life, and be extremely disabling.

    “You have to rush to the bathroom several times a day. Therefore, keeping a job or maintaining social relations can be difficult, and a lot of people isolate themselves. The disease controls their life,” says Professor Jesper Bøje Andersen from the Biotech Research & Innovation Centre.

    He and his research group and clinical cooperation partners at Herlev and Gentofte Hospital headed by Professor and Consultant Doctor Filip Krag Knop are responsible for a new study, which provides new ways of diagnosing bile acid diarrhoea and identifying the most effective treatment for the individual patient.

    “A lot of people with chronic diarrhoea don’t realise that they suffer from bile acid diarrhoea and what has caused it. This is a result of lack of knowledge among healthcare workers and the relatively complex and expensive – and for the patient difficult – process of diagnosing the disease,” says Filip Krag Knop.

    Jesper Bøje Andersen adds:

    “We have developed a new concept which may be used to diagnose the disease based on a simple blood sample. Today, diagnostics involves radiopharmaceuticals, which means that there is a radiation risk. The process is not necessarily dangerous, but unpleasant and arduous, and not all countries in the world support the method, including the US.”

    The new method means that doctors should be able to determine whether the patient has bile acid diarrhoea based on a simple blood sample. They focus on molecules known as metabolites in the blood.

    “A blood sample contains lots of different metabolites. Right now we are able to identify almost 1,300 different metabolites, and around a handful of these can be used to diagnose bile acid diarrhoea. The metabolites of bile acid diarrhoea patients form a particular pattern that makes them recognisable,” says Jesper Bøje Andersen.

    Which treatment?

    The researchers analysed blood samples from 50 patients and they quickly realised that the samples – and patients – could be divided into two groups.

    “First, we did not understand why. All the blood samples had been taken before treatment, typically at the time of diagnosis,” says Jesper Bøje Andersen.

    The patients then participated in a randomised clinical study at the Center for Clinical Metabolic Research at Herlev and Gentofte Hospital. Here the doctors studied the effect of two different treatments: the conventional treatment involving bile acid sequestrant colesevelam and a new treatment involving liraglutide, which is normally used to treat type 2 diabetes and severe overweight.

    “What is interesting is that the metabolites in the patients’ blood divided them into two groups: one that responds well to colesevelam and one that responds well to liraglutide. This suggests that we should be able to say which treatment is the most effective by analysing the patient’s blood at the time of diagnosis,” says Jesper Bøje Andersen.

    The clinical study showed that colesevelam treatment eased the bile acid diarrhoea symptoms of 50 per cent of the patients, while liraglutide treatment eased the symptoms of 77 per cent of the patients.

    Jesper Bøje Andersen, Filip Krag Knop and their research groups hope the new study will benefit the 60,000-100,000 Danes who suffer from bile acid diarrhoea.

    The majority of cases of bile acid diarrhoea is diagnosed at a very late stage or never diagnosed at all.

    “Around 40 per cent of the patients suffer from this condition for up to five years before it is diagnosed. Of course, this may be because they do not realise that it is a disease and that it can be treated. But it may also be because chronic diarrhoea is a tabooed disease,” says Filip Krag Knop.

    You can read the study, “The Serum Lipidome Unravels a Diagnostic Potential in Bile Acid Diarrhea”, in Lewinska & Kårhus et al., GUT.

     

    About bile acid diarrhoea

    When we eat high-fat food, the gallbladder releases bile acid. Bile acid helps the body absorb fat and fat-soluble vitamins from the food. Around 98 per cent of the bile acid is absorbed by the small intestine and returned via the blood to the liver. If the body either produces and/or releases excessive amounts of bile acid or if the bile acid is not reabsorbed by the blood, a large amount will end up in the large intestine. Here it will result in irritated mucosa, lack of fluid in the intestines and increased intestinal movements, all of which create symptoms of bile acid diarrhoea.

    University of Copenhagen, Faculty of Health and Medical Sciences

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  • Earliest Human Kiss Recorded in Mesopotamia 4,500 Years Ago

    Earliest Human Kiss Recorded in Mesopotamia 4,500 Years Ago

    Newswise — Recent research has hypothesised that the earliest evidence of human lip kissing originated in a very specific geographical location in South Asia 3,500 years ago, from where it may have spread to other regions, simultaneously accelerating the spread of the herpes simplex virus 1.

    But according to Dr Troels Pank Arbøll and Dr Sophie Lund Rasmussen, who in a new article in the journal Science draw on a range of written sources from the earliest Mesopotamian societies, kissing was already a well-established practice 4,500 years ago in the Middle East. And probably much earlier, moving the earliest documentation for kissing back 1,000 years compared to what was previously acknowledged in the scientific community.

    “In ancient Mesopotamia, which is the name for the early human cultures that existed between the Euphrates and Tigris rivers in present-day Iraq and Syria, people wrote in cuneiform script on clay tablets. Many thousands of these clay tablets have survived to this day, and they contain clear examples that kissing was considered a part of romantic intimacy in ancient times, just as kissing could be part of friendships and family members’ relations,” says Dr Troels Pank Arbøll, an expert on the history of medicine in Mesopotamia.

    He continues:

    “Therefore, kissing should not be regarded as a custom that originated exclusively in any single region and spread from there but rather appears to have been practiced in multiple ancient cultures over several millennia.”

    Dr Sophie Lund Rasmussen adds:

    “In fact, research into bonobos and chimpanzees, the closest living relatives to humans, has shown that both species engage in kissing, which may suggest that the practice of kissing is a fundamental behaviour in humans, explaining why it can be found across cultures.”

    Kissing as potential transmitter of disease

    In addition to its importance for social and sexual behaviour, the practice of kissing may have played an unintentional role in the transmission of microorganisms, potentially causing viruses to spread among humans.

    However, the suggestion that the kiss may be regarded as a sudden biological trigger behind the spread of particular pathogens is more doubtful. The spread of the herpes simplex virus 1, which researchers have suggested could have been accelerated by the introduction of the kiss, is a case in point:

    “There is a substantial corpus of medical texts from Mesopotamia, some of which mention a disease with symptoms reminiscent of the herpes simplex virus 1,” Dr Arbøll remarks.

    He adds that the ancient medical texts were influenced by a variety of cultural and religious concepts, and it therefore must be emphasized that they cannot be read at face value.

    “It is nevertheless interesting to note some similarities between the disease known as buʾshanu in ancient medical texts from Mesopotamia and the symptoms caused by herpes simplex infections. The bu’shanu disease was located primarily in or around the mouth and throat, and symptoms included vesicles in or around the mouth, which is one of the dominant signs of herpes infection.”

    “If the practice of kissing was widespread and well-established in a range of ancient societies, the effects of kissing in terms of pathogen transmission must likely have been more or less constant”, says Dr Rasmussen.

    Dr Arbøll and Dr Rasmussen conclude that future results emerging from research into ancient DNA, inevitably leading to discussions about complex historical developments and social interactions – such as kissing as a driver of early disease transmission – will benefit from an interdisciplinary approach.

    Read the article “The ancient history of kissing” in Science.

    University of Copenhagen

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  • Resistant bacteria are a global problem. Now researchers may have found the solution

    Resistant bacteria are a global problem. Now researchers may have found the solution

    Newswise — Staphylococcus aureus. You may have had it in connection with a wound infection. In most cases, it will pass without treatment, while severe cases may require antibiotics, which kills the bacteria. This is the case for the majority of the population. In fact, many of us – though we feel perfectly fine – carry staphylococci in the nose, a good, moist environment in which the bacteria thrive.

    However, more and more staphylococci are becoming resistant to antibiotics (also known as multi resistant staphylococcus aureus or MRSA), and these infections can be difficult to treat.

    “Antibiotics resistance is an increasing problem, especially on a global scale. And when you have this relatively simple infection which suddenly cannot be treated with antibiotics, the situation can turn serious, sometimes life-threatening,” says Professor Niels Ødum from the LEO Foundation Skin Immunology Research Center at the University of Copenhagen.

    Therefore, all over the world, a lot of resources are being invested in fighting antibiotics resistance in staphylococcus aureus infections, and a new study among skin lymphoma patients has produced positive results. A new substance called endolysins has proven capable of killing both resistant and non-resistant staphylococcus aureus – without the need for antibiotics. But we will get back to that.

    The discovery is good news to patients with a weak immune system to whom a staphylococcus aureus infection can be serious and, at worst, fatal. But it also adds to the knowledge we have of other forms of treatment.

    “To people who are severely ill with e.g. skin lymphoma, staphylococci can be a huge, sometimes insoluble problem, as many are infected with a type of staphylococcus aureus that is resistant to antibiotics,” says Niels Ødum and adds:

    “That is why we are careful not to give antibiotics to everyone, because we do not want to have to deal with more resistant bacteria. Therefore, it is important that we find new ways of treating – and not the least to prevent – these infections.”

    New substance may be the answer

    In some patients, a staphylococcus aureus will cause the cancer to worsen. And even though antibiotics appear to work in some cases, it is not without its problems.

    “We can tell that giving high doses of antibiotics to patients with serious infections causes their health, skin and cancer symptoms to improve. But once we stop giving them antibiotics, the symptoms and staphylococci quickly return. Patients experience many adverse effects, and some risk getting resistant bacteria,” says Niels Ødum.

    Therefore, treating staphylococcus aureus can be tricky. At worst, cancer patients may die of an infection which doctors are unable to treat.

    And this is where endolysins enter the scene, as this new substance may be part of the solution to antibiotics resistance like MRSA.

    “This particular endolysin is a brand new, artificially produced enzyme that has been improved several times and designed as a new drug,” explains Postdoc Emil Pallesen, who is first author of the study. He adds:

    “The great thing about this enzyme is that it has been designed to penetrate the wall of staphylococcus aureus. This enables it to target and kill the harmful staphylococcus and leave harmless skin bacteria unharmed.”

    And that is what made the researchers decide to test the new substance; they expected it to be able to kill both resistant and non-resistant staphylococcus bacteria.

    “We have been testing the substance on skin samples from patients, and it does appear to kill staphylococcus aureus from patients. Endolysins do not care whether the bacterium is resistant to antibiotics or not, because it does not work in the same way as antibiotics,” says Niels Ødum and adds:

    “The really good news is that our lab tests have showed that endolysins do not just eradicate staphylococcus aureus; they also inhibit their ability to promote cancer growth.”

    The study, “Endolysin inhibits skin colonization by patient-derived Staphylococcus aureus and malignant T cell activation in cutaneous T cell lymphoma”, is published in the Journal of Investigative Dermatology.

    University of Copenhagen, Faculty of Health and Medical Sciences

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  • Going for an immediate transition to a green economy pays off, even if such transition is very unlikely to happen, a study finds

    Going for an immediate transition to a green economy pays off, even if such transition is very unlikely to happen, a study finds

    Newswise — Nicola Botta of PIK Potsdam, Germany, and colleagues have developed a new method for assessing how much decisions matter in situations in which the consequences of such decisions are highly uncertain. Applying the method to a stylized greenhouse-gas emission problem reveals that opting for an early transition to a decarbonized society is rational even when the probability of actually realizing such a transition is very low. The work “Responsibility under uncertainty: which climate decisions matter most?”, published in Environmental Modeling & Assessment is part of the European TiPES project on tipping points in the Earth’s system.

    ”We have discovered that it is almost always the case that best decisions are still best, even when the probability that they are actually implemented becomes very, very small,” says Nicola Botta.

    In the study, the group applied a verified theory of policy advice which makes it possible to compute “best” policies for problems in which decisions have to be taken step-by-step and under uncertainty.

    These policies are then compared, at a given decision step, with the remaining options to evaluate how important it is to avoid a mistake when taking a decision at that step.

    The method was then applied to a stylized greenhouse-gas emission problem in which the goal of decision making is twofold: 1) avoid unmanageable impacts from climate change and 2) avoid hurting the economy. The program now evaluated the consequences of two options: immediately start a transition to a green economy or postpone such a transition to avoid economical damage.

    The analysis indicates that best decisions pay off even when the probability that such decisions are actually implemented becomes very low, for example, because of political uncertainty or because of the inertia of legislation.

    ”At the first glance this seems surprising, as the common wisdom is that it’s not worth betting on something that is not likely to happen”, says Nicola Botta.

    ”But, if you think twice, the result makes sense. It also provides a guideline to the discussion on whether it is worth to pursue climatetargets (like the 1.5°C target) that are unlikely to actually be met: the answer is yes.”

    ”More generally, the paper is a methodological contribution towards understanding which decisions under uncertainty matter most. Realizing that certain decisions are less important than others (or less important than expected) can be very helpful, for example in climate negotiations” explains Nicola Botta.

     

    The TiPES project is an EU Horizon 2020 interdisciplinary climate science project on tipping points in the Earth system. 18 partner institutions work together in more than 10 countries. TiPES is coordinated and led by The Niels Bohr Institute at the University of Copenhagen, Denmark and the Potsdam Institute for Climate Impact Research, Germany. The TiPES project has received funding from the European Horizon 2020 research and innovation program, grant agreement number 820970.

    University of Copenhagen, Faculty of Science

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  • Study uncovers widespread unethical practice for assigning authorships

    Study uncovers widespread unethical practice for assigning authorships

    Newswise — A recently published survey study of PhD students reveals that an ethically questionable culture for assigning authorships to research papers is widespread within the medical and natural sciences across Europe.

    Under the hashtag #pleasedontstealmywork, dozens of Danish PhD students shared their experiences last spring concerning powerful researchers who use their position to gain co-authorships on papers to which they have not made a significant contribution.

    Under the hashtag #pleasedontstealmywork, dozens of Danish PhD students shared their experiences last spring concerning powerful researchers who use their position to gain co-authorships on papers to which they have not made a significant contribution.

    A new international study led by researchers from the Department of Food and Resource Economics (IFRO) and the Department of Science Education (IND) at the University of Copenhagen now shows that these stories were only the tip of the iceberg.

    ”There are major differences across faculties, but our study shows that around a third of all PhD students working in five different European countries have granted a co-authorship to a more powerful researcher, even though the person had not made a significant contribution to the study” says Mads Paludan Goddiksen, postdoc at IFRO, and first author of the study.

    The Danish minister of higher education and research, Christine Egelund (M), tells Videnskab.dk that she finds the results worrying, and that the ministry will initiate further investigations.

    The study, published in PloS One, was conducted by an international team of researchers led from the University of Copenhagen. In the survey, 1336 PhD students from a wide range of research fields in five European countries were asked if they had granted at least one co-authorship to a person in power even though the person had not made a significant contribution to the study. 34% said yes.

    “Guest authorships like these make it difficult to see who has actually contributed to the study and skews the competition among researchers for positions and funding,” says Mads Goddiksen.

    Guest authorships are a means to maintain good relations

    The problem with guest authorships is biggest within the medical sciences, where 49% of the Ph.D. students had granted a guest authorship to a person in power. In the natural and technical sciences (STEM) it was 42%. In the other faculties, it was much less.

    Goddiksen and colleagues also asked the PhD students who had granted a guest authorship to a person in power, why they had done it. To this, 49% responded that at least a partial reason was that they had been told to do so by the person in power – 14% gave this as the only reason.

    ”In addition, it seems that some PhD students accept that more powerful researchers become guest authors on their papers to avoid conflicts,” says Mads Goddiksen. “We see that half of those who have granted guest authorship to a person in power indicate that they did it, at least partly, to maintain a good relationship to the person in power”. 

    The results are backed by another recent study  where 287 recently graduated PhD candidates from medical faculties in Scandinavia were asked if they had granted a guest authorship. Around a third said yes.

    Both studies give only the perspective of the PhD students, while the perspective of supervisors and other powerful researchers has not been included, Mads Goddiksen emphasises. Nor do the studies take into account that researchers from the natural and medical sciences generally publish a lot more papers than researchers from the humanities and social sciences, which could which could increase the likelihood of being asked to grant a guest authorship.

    A change in culture is required

    One of the researchers behind the study, Peter Sandøe, who is Head of Section at IFRO, as well as professor at the Faculty of Health and Medical Sciences and vice chair of the University’s practice committee, says that the results show an ethically questionable culture that goes against good scientific practice.

    ”It is the result of a problematic culture of authorship attribution that is deeply engrained. This may also mean that the problem is hard to get rid of. When I have raised this with influential researchers, the responses are either that the PhD students don’t know how much the senior researchers are contributing, or that our courses in responsible conduct of research for PhD students, postdocs and supervisors will solve the problem over time. Some even argue that it will affect their ability to compete with peers if they grant fewer guest authorships than is done at other universities,” says Peter Sandøe.

    Peter Sandøe therefore believes that a culture change is required. One way of doing this is by changing the how researchers are assessed. He has, for instance, been involved in assessing applications to the Swedish foundation Riksbankens Jubilæumsfond. This foundation has introduced the rule that applicants are not allowed to give their H-index, full publication lists or other quantitative measures of their research in the application. They may only provide their project application, and their five most relevant publications. Peter Sandøe hopes that such incentives to focus on quality rather than quantity will become more widespread,

    ”In this way, we focus on assessing researchers on their best publications, not the number of publications. This can hopefully create a culture without the incentives that push researchers into always needing more citations and publications. As it is now, these incentives create imbalances and undesirable side effects in the system. Researchers who have many guest authorships will appear to have produced more than they really have. This also means that in the current system, people who behave in an ethically problematic way get a head start in the competition. This needs to change,” says Peter Sandøe.

    University of Copenhagen, Faculty of Science

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  • More than two billion are infected with this disease; Vitamin D can help

    More than two billion are infected with this disease; Vitamin D can help

    Newswise — Sarcomas are cancer tumours found in e.g. the bones, muscles or fatty tissue. It is a rare type of cancer seen in only one per cent of cancer patients. It is complex and difficult to treat.

    However, a new study may have found a new treatment that can help the sickest sarcoma patients.

    “We have learned that sarcoma patients whose cancer cells have a high expression of the cep135 protein are worse off. But inhibiting a gene called plk1 also inhibits growth of the sarcoma cells, and this suggests that we can target the treatment of the sickest sarcoma patients,” says Associate Professor Morten Scheibye-Knudsen from the Center for Healthy Aging at the Department of Cellular and Molecular Medicine, who is responsible for the new study.

    Methods for identifying sarcoma patients’ prognoses are already available, as are different forms of treatment. But the new study has identified a new method.

    “This is a new way of stratifying and possibly a new and better way of treating sarcoma. And the introduction of yet another method is always good news to patients. Because no two cancers are alike. Ideally, treatment should always be tailored to the individual patient,” Morten Scheibye-Knudsen stresses.

    He hopes other researchers with access to the necessary test facilities will study his results in more detail and eventually design a new treatment. If the method turns out to work, he believes a new treatment may be available to patients in five to 10 years.

    Grey hair, wrinkles and loss of fatty tissue at an early age

    Morten Scheibye-Knudsen and his colleagues started out by studying patients suffering from the rare neurological disorders Werner’s syndrome, Nijmegen breakage syndrome and Ataxia-telangiectasia syndrome.

    These patients experience symptoms of early ageing such as grey hair, wrinkles and loss of fatty tissue – and they have a high risk of developing cancer at an early age.

    “Age-associated diseases such as cancer is one of my main areas of interest as a researcher at the Center for Healthy Aging. As we grow older, a lot of things happen to the body, and determining causality can be difficult. But in people suffering from e.g. Werner’s syndrome it is easier to see which genes are responsible for which processes. This gives us a molecular handle, so to speak,” says Morten Scheibye-Knudsen.

    In order to establish why these patients develop cancer at an early age, the researchers compared gene expressions across the three disorders. Here they worked together with the company Insilico Medicine, whose large Pandaomics platform made it possible to identify gene mutations in thousands of different disorders. It turned out that cep135 is a common denominator for the cancer genes of the three disorders.

    “This made us study the gene expressions of various cancers, and we learned that cep135 is associated with high mortality in i.a. sarcoma, but also in bladder cancer. Sarcoma was particularly interesting, as many Werner’s syndrome patients develop sarcoma,” explains Morten Scheibye-Knudsen.

    Finally, the researchers sought to find ways to inhibit the sarcoma. Cep135 is not a useful target, as it is a so-called structural protein, which are difficult to target. Instead, the researchers learned that by inhibiting the plk1 gene they were able to target the sarcoma.

    “The study indicates that we can use genetic diseases that exhibit accelerated aging to identify new treatment targets. In this study, we investigated cancer, but the method can in principle be used for all age-related diseases such as dementia, cardiovascular diseases and others,” says Morten Scheibye-Knudsen.

    Read the entire study, ”High-confidence cancer patient stratification through multiomics investigation of DNA repair disorders”, in CDDpress.

    What are sarcomas?

    Sarcomas are cancer tumours found in i.a. the bones, muscles or fatty tissue. There are two main types: bone sarcoma and soft tissue sarcoma (muscles, fatty tissue, connective tissue, blood vessels and neurilemma).

    Sarcoma affects one per cent of cancer patients. In Denmark, around 45 people are diagnosed with bone sarcoma each year and 220 with soft tissue sarcoma. Adults diagnosed with bone sarcoma have a 60-per cent five-year survival rate, while adults diagnosed with bone sarcoma have a 50-70-per cent five-year survival rate.

    University of Copenhagen, Faculty of Health and Medical Sciences

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  • 20 new gurgling and creaking frog species from Madagascar named

    20 new gurgling and creaking frog species from Madagascar named

    Newswise — Taxonomists are working against the clock to discover and catalogue new species before they disappear, to make it possible to protect our planet’s remaining biodiversity. Major strides are needed to move towards completing the biological inventory on Earth. Now, a large international team has made a huge stride forward on the taxonomy of Madagascar’s frogs, naming 20 new species at once. The article was published under open access in the journal Megataxa.

    The frogs belong to the genus Mantidactylus subgenus Brygoomantis, which contained just 14 species until now. These small, brown frogs are ubiquitous along streams in Madagascar’s humid forests, but are inconspicuous to the eye. The males emit very subtle advertisement calls to attract females. ‘The calls typically sound like a creaking door, or a gurgling stomach’ says lead author, Dr Mark D. Scherz, Curator of Herpetology at the Natural History Museum of Denmark, ‘Finding, recording, and catching calling individuals of these frogs is a real challenge, but has proven critically important for the discovery and description of these many new species. That means a lot of time on hands and knees in the mud.’

    The team has been building to this for a long time. ‘This is the culmination of intensive fieldwork across Madagascar over more than 30 years’ says Dr Frank Glaw, Curator of Herpetology at the Zoologische Staatssammlung München, in Munich, Germany, ‘Our dataset contains genetic data from over 1300 frogs, and measurements of several hundred specimens.’

    One key tool in the authors’ arsenal was the use of cutting-edge ‘museomics’, where DNA is sequenced from old museum material. This is often difficult, because DNA degrades over time and due to various chemicals that are used to preserve animal specimens. But using an approach called ‘DNA Barcode Fishing’, the team were able to get useable DNA sequences from most of the relevant museum material. ‘Museomics gave definitive identifications of sometimes very ambiguous-looking specimens,’ says senior author, Professor Miguel Vences of the Technische Universität Braunschweig, ‘This gives us a level of confidence in our species descriptions that was not previously possible based on morphology alone.’

    Even this huge stride forward doesn’t seem to be the last word on the subgenus Brygoomantis. ‘There are still several Brygoomantis lineages that are probably separate species, but that we didn’t have enough data or material for,’ says Dr Andolalao Rakotoarison, co-chair of the Amphibian Specialist Group for Madagascar, ‘Even for those species for which we have names, we know almost nothing about their biology or ecology. We need a lot more field research on these frogs, and more specimens in museum collections, to really gain a good understanding of them.’

    Citation: Scherz, M.D., Crottini, A., Hutter, C.R., Hildenbrand, A., Andreone, F., Fulgence, T.R., Köhler, G., Ndraintsoa, S.H., Ohler, A., Preick, M., Rakotoarison, A., Rancilhac, L., Raselimanana, A.P., Riemann, J.C., Rödel, M.-O., Rosa, G.M., Streicher, J.W., Vieites, D.R., Köhler, J., Hofreiter, M., Glaw, F. & Vences, M. (2022) An inordinate fondness for inconspicuous brown frogs: integration of phylogenomics, archival DNA analysis, morphology, and bioacoustics yields 24 new taxa in the subgenus Brygoomantis (genus Mantidactylus) from Madagascar. Megataxa. https://doi.org/10.11646/megataxa.7.2.1

    University of Copenhagen

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