Culture

A new paper by the Dynamical Systems Biology lab at UPF shows that the response by bacteria to antibiotics may depend on other species of bacteria they live with, in such a way that some bacteria may make others more tolerant to antibiotics. The study, which was conducted by the researchers Letícia Galera-Laporta and Jordi Garcia-Ojalvo and is published today in the journal Science Advances, may affect the treatment of bacterial infections, even suggesting new strategies to combat these pathogens.

Since the discovery of penicillin almost 90 years ago, antibiotics have saved millions of lives. The required concentration of each antibiotic to eliminate a wide variety of species of bacteria is currently known in detail. These analyses are usually performed in cultures where each species of bacteria lives alone. However, infections are often comprised of more than one species of bacteria, with many species being present at the same time that can interact, sharing all types of chemical signals. In addition, our body contains a large number of beneficial bacteria (microbiota), with which pathogens can also coexist. Therefore, in this study, the researchers examined how communities of multiple species of bacteria respond jointly to antibiotics.

To address this question, Galera-Laporta and Garcia-Ojalvo studied how the bacteria Bacillus subtilis and Escherichia coli respond to the antibiotic ampicillin (penicillin family). Alone, E. coli is sensitive to this antibiotic -beyond a certain concentration it cannot grow- and B. subtilis is tolerant -it manages to grow-. Letícia-Galera Laporta explains that "counterintuitively, we observed that when the two species of bacteria coexist, their response to the antibiotic is opposite to when they are alone. The bacteria that could survive dies and vice versa". With the help of a mathematical model, they saw that what varies is the collective response, as a result of the change in the availability of the drug for each species of bacteria in the presence of the other.

Two bacteria coexist... and one of them takes advantage

Ampicillin inactivates certain proteins required for bacteria to manufacture their cell wall and thus prevents the latter from growing. Bacillus subtilis tolerates this antibiotic because it inactivates the antibiotic and reduces the free amount circulating in the environment. This benefits E. coli when the two species coexist, because it makes the amount of ampicillin not reach the threshold needed to kill it.

In contrast, E. coli is not able to inactivate the antibiotic, rather it acts like a sponge: it retains the antibiotic for a while and then returns it to the environment. This buffer role delays the suppression of the antibiotic in the environment, and therefore harms B. subtilis: it makes the antibiotic remain in the environment for a period in which B. subtilis would have eliminated had it been alone.

Most studies of this kind focus on genetic resistance to antibiotics through mutations, which is a very important aspect. "But through studies like these, we wish to show the importance of not losing sight of the fact that bacteria's survival of antibiotics can be due to other, non-genetic mechanisms", explains Jordi Garcia-Ojalvo, full professor of Systems Biology at the Department of Experimental and Health Sciences (DCEXS) at UPF.

The mechanisms shown in this study are not specific to the two species of bacteria and the antibiotics used. This finding bears out the difficulty of choosing the correct antibiotic dose in treating bacterial infections, because the available information refers to species when they are found alone. On the other hand, the study also suggests the possibility of using non-pathogenic bacteria to sensitize others that are harmful. In short, "we must consider the microbial context in which the bacteria are found, in order to improve the information that enables choosing the appropriate dose of antibiotic in each case", Garcia-Ojalvo concludes.

Similar to humans, wild animals' reaction to disturbance is accompanied by releasing hormones, such as cortisol. To understand the impact of various "stress" factors - for example, competition for food, encounters with predators, or changing environmental conditions - on wildlife, scientists first need to determine the baseline levels of relevant hormones for each species. Researchers from the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) now uncovered possible pitfalls of the commonly used hormone analysis method that overestimate concentrations of cortisol and thus lead to overstated conclusions. They investigated whether glucocortiocoid hormones deposited in animal hair can be reliable biomarkers to indicate the impact of disturbances. The source of errors in the commonly used antibody-based enzyme immunoassays (EIA) method is described in a recently published article in the scientific journal "Conservation Physiology".

Scientists led by Prof. Katarina Jewgenow, head of the Department of Reproduction Biology at Leibniz-IZW, conducted a comparative analysis on the hair samples from six mammalian species: Egyptian mongoose (Herpestes ichneumon), Iberian lynx (Lynx pardinus), cheetah (Acinonyx jubatus), spotted hyena (Crocuta crocuta), Asiatic black bear (Ursus thibetanus), and Alpine marmot (Marmota marmota). They measured the concentration of the "stress" hormone cortisol in hair extracts using the widely applied method of antibody-based enzyme immunoassays (EIA). This method is based on the ability of an antibody to recognize a three-dimensional molecule structure specific to a particular hormone. Such antibodies will also bind to closely related molecules which express similar structures. Usually such "group"-specific antibodies are very useful for wildlife species - where the relevant "stress" hormone is often unknown - but it also means that the concentration of other substances might be measured that are irrelevant to the biological process under observation, in the case of "stress" hormones such as cortisol to a stressful situation.

To be certain that the natural hormone was extracted from mammalian hair the researchers compared the EIA results to a more comprehensive and precise procedure, a mass spectrometry analysis. They discovered significant discrepancies in the indicated hormone levels. The EIA overestimated the concentration of cortisol by up to ten times. Further biochemical analysis showed that this overestimate was not connected with any substance related to cortisol, but rather to unknown hair born molecules. For that reason they strongly recommend a careful validation of each EIA before using it to the analysis of hormones from hair samples. As it is already known that age, sex and time of the year might influence baseline hair cortisol level, information about age and sex of the individual and the sampling date should also be available.

In a previous study Leibniz-IZW doctoral student Alexandre Azevedo analysed hair samples of Egyptian mongooses (Herpestes ichneumon) from seven provinces of Portugal. He and his colleagues wanted to know whether the successful reintroduction of the Iberian lynx to Portugal is a stressful influence on the mongoose population as the Iberian lynx is a direct food competitor to the mongoose, but lacked a suitable method.

Collecting hair samples is currently frequently suggested as a non-invasive way of assessing "stress" levels as they can be collected without disturbing the animal. "Taking blood samples to measure cortisol concentrations in the serum itself causes considerable stress. Cortisol metabolites can also be detected in faeces, but finding out which individual defecated is quite complicated in free-ranging animals unless the defecation was actually witnessed by the observer", says Jewgenow. "In contrast, hair samples are often obtained in a minimally invasive way using 'hair-traps' which are usually installed to collect samples for genetic analyses from wildlife population." Now such samples can also be used to determine the concentration of cortisol in hair provided the analytical method has been previously validated.

(Jena, Germany) A world without robots is now almost inconceivable. Not only do they take on important tasks in production processes, they are also increasingly being used in the service sector. For example, machines created to resemble humans - known as androids - are helping to care for elderly people. However, this development conflicts with the preconception that senior citizens are rather hostile to technology and would be sceptical about a robot. A study by psychologists of Friedrich Schiller University Jena, Germany suggests, however, that older people are far less anxious and hostile regarding such 'human robots' than previously thought.

Robots need to look human

During their series of experiments, the results of which have now been published in the specialist journal 'Computers in Human Behaviour', the Jena researchers showed videos of various robots to 30 participants aged around 70 and 30 others aged around 20. The participants were asked to evaluate whether they found the robot friendly or threatening and whether they could imagine it as a daily companion.

"In the tests, the older participants made a clearly positive assessment of the machines - and were even more open-minded towards them than the younger comparison group," says Prof. Stefan Schweinberger of the University of Jena. "In the older participants, we were unable to confirm a scepticism towards robots that is frequently assumed in science." Although it was a relatively small series of tests, two further, yet unpublished, studies carried out in Jena arrived at the same result. The decisive factor had been how human the machines looked, for example whether they had facial expressions, arms and legs, and how human-like these appeared to be. The new findings could perhaps help in designing service robots.

People with autism are more in tune with machines

In their experiments, Schweinberger and his team also analysed to what extent the participants exhibited autistic personality traits. "Although none of the participants in the study had a diagnosis of autism, the autism spectrum is now seen as a continuum that includes all people, to a greater or lesser extent. More pronounced autistic personality traits on an appropriate scale may give us further clues as to how open people are to machines", explains Schweinberger.

This is because previous studies have shown that people with more pronounced autistic traits are more open to robots. Contact between them is even used as a therapeutic approach. "People with autism often have handicaps in the area of social communication; for example, they cannot interpret facial expressions correctly. It is important for them that their environment is predictable," says Schweinberger. "With its automated communication - more predictable when compared with a human partner - a robot could help with this."

Due to its small number of participants, the Jena study did not produce any conclusive figures. However, slight tendencies suggest that people with a greater predisposition to autism are more in tune with machines. Such personality traits are stronger in older people in particular, which might favour their openness towards robots. Further studies should be carried out in this field, so that we can better understand the increasingly relevant relationship between human and machine.

First trial of its kind finds that treatment with triple artemisinin-based combination therapies (TACTs) is effective.

TACTs were safe and well tolerated, but showed slightly higher rates of vomiting and some minor changes in the electrical activity of the heart compared to existing treatment that uses two drugs.

Drug resistance is a major threat to malaria control and elimination. The authors say that triple therapies are potentially an immediately available new treatment option that could improve outcomes in countries with multidrug resistant malaria.

The first clinical trial of two triple artemisinin-based combination therapies for malaria finds that the combinations are highly efficacious with no safety concerns.

Published in The Lancet, the study of 1,100 people with uncomplicated falciparum malaria from eight countries compared people receiving the current national first-line treatment combining two drugs, with two forms of triple therapy (dihydroartemisinin-piperaquine plus mefloquine and artemether-lumefantrine plus amodiaquine).

The triple therapies (known as triple artemisinin-based combination therapies - TACTs), combine existing treatment consisting of two drugs (artemisinin-based combination therapies - ACTs) with a second partner drug that remains present in the blood to target the malaria parasites for longer. TACTs add additional antimalarial activity and provide mutual protection for the partner drugs, and researchers believe that it might provide effective treatment and could potentially delay the emergence of antimalarial drug resistance.

ACTs have contributed substantially to the reduction in the global burden of malaria. However, progress is now threatened by the emergence and spread of artemisinin and artemisinin partner-drug resistance in southeast Asia. Emerging multidrug resistance in the malaria parasite has led to a series of treatment policy changes, but this means fewer treatments are available and new compounds are not becoming available quickly enough in countries facing drug resistant malaria.

With the risk of the spread of multidrug resistant malaria to India and sub-Saharan Africa, it is important to find new treatments to treat drug-resistant infections and help prevent the emergence of multidrug resistance.

"With the increasing failure of conventional ACTs, the use of TACTs might soon become essential for treatment of malaria in the Greater Mekong subregion in southeast Asia. This region is aiming for accelerated malaria elimination before the growing drug resistance renders Plasmodium falciparum malaria close to untreatable. The TACTs we studied here could prevent a resurgence of malaria that often accompanies spreading antimalarial drug resistance." says senior author Professor Arjen Dondorp, Mahidol-Oxford Research Unit, Bangkok, Thailand. [1]

Co-author, Dr Chanaki Amaratunga, Mahidol-Oxford Research Unit, Bangkok, Thailand, says: "Because two well-matched partner drugs provide mutual protection against resistance, deployment of TACTs is expected to extend the useful life of the few effective available and affordable antimalarial drugs. Fortunately, to date, artemisinin resistance has not worsened in southeast Asia and has not spread to sub-Saharan Africa, so these drugs still provide useful antimalarial treatment when used in combination. To ensure we reduce resistance as much as possible, it is important that we avoid waiting for resistance to emerge and spread before changing malaria therapies." [1]

The new study was an open-label randomised controlled trial including 1,100 patients aged 2-65 years from 18 hospitals in eight countries (Thailand, Cambodia, Vietnam, Myanmar, Laos, Bangladesh, India and the Democratic Republic of the Congo). Participants were included if they had acute, uncomplicated P falciparum malaria alone or mixed with non-falciparum species, and a temperature of 37.5°C or higher, or a history of fever in the past 24 hours. People who had been treated with artemisinins in the past week, and people with a history of problems with the electrical activity of their heart were not included in the study.

The ACTs and TACTs assigned in the trial depended on the first-line ACTs used in the country where the participant was being treated. In some cases, where a country's first-line treatment changed during the trial (due to that treatment beginning to fail due to resistance), the comparison treatment in the trial was also changed. Doses varied by drug combination and location, and all drugs were administered orally.

Participants in Thailand, Cambodia, Vietnam, and two sites in Myanmar were assigned to either dihydroartemisinin-piperaquine or dihydroartemisinin-piperaquine plus mefloquine. Due to changes in Cambodia's first-line treatment, at three sites participants were later assigned to either artesunate-mefloquine or dihydroartemisinin-piperaquine plus mefloquine. In Laos, one site in Myanmar, Bangladesh, India, and the Democratic Republic of the Congo, participants were assigned to either artemether-lumefantrine or artemether-lumefantrine plus amodiaquine.

The researchers assessed the efficacy of the treatment based on the complete cure of the infection assessed after 42 days of follow-up (comprised of absence of malaria parasites as well as clinical symptoms). They also recorded any adverse events associated with the treatments.

Overall, 17% of participants were given dihydroartemisinin-piperaquine (183/1,100 people), a quarter were given dihydroartemisinin-piperaquine plus mefloquine (269 people), 7% were given artesunate-mefloquine (73), 26% were given artemether-lumefantrine (289), and 26% were given artemether-lumefantrine plus amodiaquine (286).

In 15 sites, the study was stopped before target recruitment was reached because of a sharp decrease in malaria cases in those study sites, but their data still contributed to the analysis. In addition, 113 patients were excluded from the more strict "per protocol" analysis.

Six patients discontinued the study drug and started standard antimalarial treatment due to abnormal baseline laboratory results or extension of the QTc-interval. Their results were included in the trial.

In Cambodia, Thailand, and Vietnam, efficacy of the TACT dihydroartemisinin-piperaquine plus mefloquine was greater than for the ACT dihydroartemisinin-piperaquine (98% [successful treatment in 149 of 152 people] vs 48% efficacy [67/141 people], respectively). While in Myanmar, which used the same treatments, the efficacy of the ACT was similar to the efficacy of the TACT (91% [42 of 46 people] vs 100% [42 of 42 people], respectively).

In the three Cambodian sites where the drugs tested were changed during the trial, the efficacy of the TACT dihydroartemisinin-piperaquine plus mefloquine and the ACT artesunate-mefloquine were comparable (95% [69/73] vs 96% [68/71], respectively).

Comparing the TACT artemether-lumefantrine plus amodiaquine and the ACT artemether-lumefantrine in five countries, the authors found that their efficacies were similar (98% [281/286] vs 97% [279/289], respectively).

Both TACTs were well-tolerated and safe, although vomiting within an hour of treatment was more common after dihydroartemisinin-piperaquine plus mefloquine than after dihydroartemisinin-piperaquine (3.8% [30/794 people] vs 1.5% [8/543 people]), and adding amodiaquine to artemether-lumefantrine led to some changes in the electrical activity of the heart (ie, extended the electrocardiogram corrected QT interval - mean increase at 52 hours was 8.8 milliseconds for the triple therapy vs 0.9 milliseconds for the double therapy), which does not have clinical importance.

The incidence of serious adverse events was similar after treatment with ACTs or TACTs. Overall, 24 serious adverse events were reported in 1,100 patients, of which 11 were judged to be possibly (n=10) or probably (n=1) drug related.

"The TACTs used in this study combine existing antimalarial drugs and could be made available in the near future and might buy important time before new antimalarial compounds become available. In areas not yet affected by antimalarial resistance, TACTs might have the potential to delay the emergence and spread of antimalarial resistance and could help prevent importation of drug resistance from the Greater Mekong subregion, but we will need more research to confirm this." Concludes Dr Rob van der Pluijm, lead author of the paper, from the Mahidol-Oxford Research Unit, Bangkok, Thailand. [1]

The authors note some limitations in their study, including that it did not include many children - who are the main group affected by malaria. Since the study was open-label (ie, patients knew which drug they were receiving), this may have affected reporting of symptoms and adverse effects but the authors say it is unlikely to have affected efficacy.

Writing in a linked Comment, Professor Philip Rosenthal (who was not involved in the study), University of California, San Francisco, USA, says: "These new results suggest that TACTs might replace ACTs. The addition of mefloquine to dihydroartemisinin-piperaquine rescued the regimen from unacceptably poor efficacy, and mefloquine might additionally restrict selection of resistance to piperaquine. If safety and tolerability remain acceptable in follow-up studies, use of optimally dosed and formulated TACTs to treat P falciparum malaria might soon be appropriate in regions with artemisinin resistance. However, most cases of P falciparum malaria occur in regions without established artemisinin resistance... Thus, this study offers promise for TACTs in regions with artemisinin resistance, but whether we should implement TACTs in other areas is uncertain. In any event, TACTs should be seen as a stopgap; novel combination therapies to treat malaria are greatly needed."

In one of the first studies to explicitly account for fragmentation in tropical forests, researchers report that smaller fragments of old-growth forests and protected areas experienced greater losses than larger fragments, between 2001 and 2018. The results suggest tropical forests are likely to continue shrinking if large-scale efforts to protect blocks of natural forest are not swiftly implemented. Matthew Hansen et al. emphasize that distinct conservation strategies are needed to combat deforestation in large forest blocks as compared to in smaller, more fragmented regions. In the latter case, efforts should focus on connecting small forest fragments, the authors say, to reestablish wide-ranging tree cover. This would be important in Central America, West Africa, and Southeast Asia, where contiguous natural forest blocks are absent. By contrast, an approach aimed at conserving large existing forests is required for the Amazon Basin, Congo Basin, Indonesian Borneo, and the island of New Guinea, say Hansen and colleagues. While many previous studies have documented tropical forest fragmentation, none have incorporated measures of fragmentation with data explicitly documenting the spatial extent of forest loss, since changes in tree cover are not typically included in monitoring protocol. To better understand how fragmentation affects forest cover loss, Hansen and colleagues first analyzed maps of tropical tree cover for the year 2000, identifying fragments at least 10 square kilometers large. The researchers then calculated forest loss per fragment over the following 18 years, calculating the loss as a percentage of fragment size. Smaller chunks of forest experienced proportionally higher losses, with the 36,282 smallest fragments (under 675 square kilometers) losing 11.5% of their tree cover each year, while the 22 largest stretches (greater than 75,000 square kilometers) lost 2% each year. Hansen and colleagues note that forested areas largely managed for economic purposes did not experience declines related to fragment size, since resources were invested to protect the lands.

They are among the most recognisable dinosaurs ... now palaeontologists have discovered that stegosaurs left a lasting impression on a Scottish island.

Around 50 newly identified footprints on the Isle of Skye have helped scientists confirm that stegosaurs - with their distinctive diamond-shaped back plates - roamed there around 170 million year ago.

The site on the island's north-east coast - which was at the time a mudflat on the edge of a shallow lagoon on a long-lost island in the Atlantic - contains a mixture of footprints, and reveals that dinosaurs on Skye were more diverse than previously thought.

A team of palaeontologists from the University of Edinburgh discovered a short sequence of distinctive, oval footprints and handprints belonging to a stegosaur, left by a young animal or a small-bodied member of the stegosaur family as it ambled across the mudflat.

The discovery means that the site at Brothers' Point - called Rubha nam Brathairean in Gaelic - is now recognised as one of the oldest-known fossil records of this major dinosaur group found anywhere in the world. Large stegosaurs could grow to almost 30 feet long and weigh more than six tonnes.

Skye is one of the few places in the world were fossils from the Middle Jurassic period can be found. Discoveries on the island have provided scientists with vital clues about the early evolution of major dinosaur groups, including huge, long-necked sauropods and fierce, meat-eating cousins of Tyrannosaurus rex.

The study, published in the journal PLOS ONE, was supported by a grant from the National Geographic Society. It also involved scientists from National Museums Scotland, University of Glasgow, Federal University of Rio de Janeiro, and the Staffin Museum on the Isle of Skye.

Paige dePolo, a PhD student at the University of Edinburgh's School of GeoSciences, who led the study, said: "These new tracksites help us get a better sense of the variety of dinosaurs that lived near the coast of Skye during the Middle Jurassic than what we can glean from the island's body fossil record. In particular, Deltapodus tracks give good evidence that stegosaurs lived on Skye at this time."

Dr Steve Brusatte, also of the School of GeoSciences, who was involved in the study and led the field team, said: "Our findings give us a much clearer picture of the dinosaurs that lived in Scotland 170 million years ago. We knew there were giant long-necked sauropods and jeep-sized carnivores, but we can now add plate-backed stegosaurs to that roster, and maybe even primitive cousins of the duck-billed dinosaurs too. These discoveries are making Skye one of the best places in the world for understanding dinosaur evolution in the Middle Jurassic."

A study led by the Universitat Autònoma de Barcelona (UAB) reconstructs the entire trophic chain of a prehistoric site in Western Europe with samples from this Bronze Age settlement located in the southeast of the Iberian Peninsula.

The economy of La Bastida would have been more productive than other Argaric sites due to their fields being fertilised regularly by the grazing of livestock, which would have favoured a prominent development within the Argaric communities.

The study, published in PLOS ONE, for the first time dates the age of weaning of infants from the Bronze age, placing it before the age of 2, and establishes differences in the diet of the elite, richer in meat.

The research questions the reconstruction of the prehistoric human diet from stable isotopes if only human remains are analyzed.

A team from the Research Group in Mediterranean Social Archaeology (ASOME) at the Universitat Autònoma de Barcelona (UAB) has led an international study to reconstruct the diet of the El Argar society (2220-1550 BCE) and distinguish the subsistence strategies of the different populations of this archaeological complex located in the southeast of the Iberian Peninsula. Published in PLOS ONE, the study was conducted with biological material extracted from the excavation site of La Bastida in Totana, Murcia, one of the oldest cities in Europe, and from another smaller site known as Gatas, located in Turre, Almeria.

This is the first project that analyses all levels of the food chain of a prehistoric society in the Western Mediterranean - plants, herbivores, carnivores and omnivores. The combined analysis of stable nitrogen and carbon isotopes, found among the different types of plants and both terrestrial and marine animals, has allowed scientists to reconstruct the whole food chain and interpret results based on a highly reliable set of comparative data.

In addition to the members of the ASOME group at the UAB Department of Prehistory, participating in this study were researchers from the Curt-Engelhorn-Centre of Archaeometry gGmbH in Mannheim (Deutschland), the Danube Private University-Centre of Natural and Cultural Human History, Krems (Austria), as well as the CTFC - AGROTECNIO Mixed Unit and the University of Lleida (Spain).

Similar Diets, Different Management of Livestock

The study indicates that both settlements had a similar diet, mainly based on the consumption of barley and to a lesser extent wheat, with some meat and dairy products. However, they applied different subsistence strategies.

The inhabitants of La Bastida worked the fertile Guadalentín valley, far from the mountain slopes and non-arable lands surrounding the city. Their animals grazed on these lands and fed on stubbles, possibly in enclosures built after harvesting the fields. This complementary management of livestock made animal dung a valuable manure for these lands, increasing its fertility and crop productivity. At Gatas, in contrast, the population took on a more extensive management strategy, with a large amount of forage originating from the natural resources found near the settlement.

"La Bastida practised more intensive land management, combining agriculture and animal husbandry, and this allowed them to increase their farming economy and feed a considerably numerous population - one thousand people at that time", explains Cristina Rihuete, researcher at the UAB Department of Prehistory. "Although they grew crops in fileds that were more degraded due to intensive usage, this system meant that they had a better productive economy when compared to other smaller populations in their vicinity. Here lies one of the until now unsuspected differential economic successes of La Bastida's land management, which undoubtedly worked in favour of their political and regional dominance".

The data points to the decline of La Bastida beginning around the year 1750 BCE. "Diets poorer in protein and more intensive farming are evidence of a subsistence crisis that, according to our hypothesis, brought the El Argar society to an abrupt end. However, we must continue our research to confirm this", states Roberto Risch, also researcher at the UAB Department of Prehistory.

Weaning Before the Age of Two

The study also served to establish, for the first time, the age of infant weaning during the Bronze Age in the Iberian Peninsula. Analysis of infant remains indicates that between 18 and 24 months, all infants had culminated the process of substituting breastfeeding with a diet mainly based on cereal pap.

Males and females ate the same things at La Bastida, but the fact that the three individuals found in the two wealthiest tombs (two women and one man) yielded a larger proportion of meat and dairy products in the analyses points to a differentiation in social classes.

Call to Review Prehistoric Diet Studies

These results and the comparison with isotopic studies of other settlements in which only human remains had been studied sheds doubt on the reconstructions previously made of a prehistoric diet. According to researchers, it is advisable to review this information.

"If we had analysed only human bones, we would have come to the conclusion that the inhabitants of La Bastida and Gatas had different diets" specifies Corina Knipper, researcher at the Curt-Engelhorn-Centre of Archaeometry in Mannheim and lead author of the paper.

The study points out that the variation in nitrogen led to deduce that the former had a diet based mainly on meat and dairy products. However, that was not so due to the amount of milling equipment and grain storage facilities found at La Bastida.

"The analysis of the isotope composition of the grain has allowed us to pinpoint the reason for this difference. The high values of nitrogen-15 in individuals from La Bastida are the result of a greater presence of this natural isotope in livestock manure and its transfer to the cereal grains which were their staple food", states Jordi Voltas, researcher at the CTFC - AGROTECNIO Mixed Unit and the University of Lleida.

To conduct the study, researchers analysed the human remains of 75 individuals (52 from La Bastida and 23 from Gatas), the bone collagen of 29 animals and 105 charred cereal grains (76 barley grains and 29 wheat grains).

Preventing the death of neurons during brain growth means these 'zombie' cells can develop into functioning neurons, according to research in fruit flies from the Crick, the University of Lausanne (UNIL) and the Max Planck Institute for Chemical Ecology.

During brain development, a large number of neurons destroy themselves as part of an essential regulatory mechanism that removes excess cells. In certain areas of the human brain, this cellular "suicide", which is called apoptosis, affects about 50% of neurons.

This research, published in Science Advances and conducted in fruit flies (Drosophila melanogaster), found that by stopping the death of these cells they later developed new networks of neurons, with roles and properties that are not identical to those of existing neurons.

The researchers genetically inhibited the last stage of apoptosis in neurons of the fly olfactory system. They found that the rescued 'zombie' cells, which would have otherwise been destroyed, developed into functioning olfactory neurons that were able to detect smells. However, the 'zombie' neurons expressed different olfactory receptors than their standard counterparts. For example, some of the 'zombie' neurons found in an olfactory organ called the maxillary palp, had receptors to detect carbon dioxide, a cue used by insects to sense the presence of animals and humans, as these exhale carbon dioxide when breathing. These extra neurons gave the flies similar characteristics to mosquitos (Anopheles gambiae), which, unlike flies, also have carbon dioxide-sensing olfactory neurons in their maxillary palps. The two species have a common ancestor that lived around 250 million years ago.

"When the neurons that normally die were protected from apoptosis they developed into 'zombie' neurons that have similar characteristics as certain neurons in mosquitos. Apoptosis therefore is one factor responsible for how mosquitos and fruit flies have adapted over time to their different environments," says Lucia Prieto-Godino, co-first author and group leader of the Crick's Neural Circuits and Evolution Laboratory.

"From an evolutionary point of view, our results suggest that changes in patterns of cell death in the nervous system could allow a species to adapt to new pressures from its environment, by enabling the evolution of new populations of neurons with novel structural and functional properties," said Richard Benton, senior author and group leader at the Center for Integrative Genomics at UNIL.

While the researchers did not study in detail the behaviour of flies with more olfactory neurons, this increase theoretically allows them to perceive odours with higher sensitivity. This could play a role in helping them to detect a partner, food or danger and thus represent an advantage compared to other individuals.

The popular painkiller ibuprofen may have more significant effects on the liver than previously thought, according to new research from the University of California, Davis. The study in laboratory mice also shows marked differences between males and females.

The work is published Feb. 25 in Scientific Reports.

Ibuprofen belongs to a group of drugs called nonsteroidal anti-inflammatory drugs, or NSAIDs, widely used over the counter to treat pain and fever. It's well-established that ibuprofen can cause heart problems and increase stroke risk, but the effects on the liver were less well understood, said Professor Aldrin Gomes, Department of Neurobiology, Physiology and Behavior in the UC Davis College of Biological Sciences.

Gomes, postdoctoral researcher Shuchita Tiwari and colleagues dosed mice with a moderate amount of ibuprofen for a week -- equivalent to an adult human taking about 400 mg of the drug daily. Then they used advanced mass spectrometry at UC Davis' Proteomics Core Facility to capture information on all the metabolic pathways in liver cells.

"We found that ibuprofen caused many more protein expression changes in the liver than we expected," Gomes said.

At least 34 different metabolic pathways were altered in male mice treated with ibuprofen. They included pathways involved in metabolism of amino acids, hormones and vitamins as well as production of reactive oxygen and hydrogen peroxide inside cells. Hydrogen peroxide damages proteins and stresses liver cells.

Different effects in male and female mice

The researchers found that ibuprofen had different, and in some cases opposite, effects in the livers of male and female mice. For example, the proteasome -- a waste-disposal system that removes unwanted proteins -- responded differently in males and females. Ibuprofen elevated activity of cytochrome P450, which breaks down drugs, in females but decreased it in males.

"The elevation in cytochrome P450 could mean that other drugs taken with ibuprofen could stay in the body for a longer duration in males and this has never been shown before. No drug is perfect, as all drugs have side effects. However, many commonly used drugs such as ibuprofen are being overused and should not be used for certain conditions such as mild pain," Gomes said.

In the long term, it is important for the scientific community to start addressing differences between males and females with respect to drug metabolism and effects, he said.

CLEMSON, South Carolina - Just as there is a mysterious dark matter that accounts for 85 percent of our universe, there is a "dark" portion of the human genome that has perplexed scientists for decades. A study published March 9, 2020, in Genome Research identifies new portions of the fruit fly genome that, until now, have been hidden in these dark, silent areas.

The collaborative paper titled "Gene Expression Networks in the Drosophila Genetic Reference Panel" is the culmination of years of research by Clemson University geneticists Trudy Mackay and Robert Anholt. Their groundbreaking findings could significantly advance science's understanding of a number of genetic disorders.

The "dark" portion refers to the approximate 98 percent of the genome that doesn't appear to have any obvious function. Only 2 percent of the human genome codes for proteins, the building blocks of our bodies and the catalysts of the chemical reactions that allow us to thrive. Scientists have been puzzled by this notion since the 1970s when gene sequencing technologies were first developed, revealing the proportion of coding to noncoding regions of the genome.

Genes are traditionally thought to be transcribed into RNAs, which are subsequently translated into proteins, as dictated by the central dogma of molecular biology. However, the entire assemblage of RNA transcripts in the genome, called the transcriptome, contains RNA species that appear to have some other function, apart from coding for proteins. Some have proposed that noncoding regions might contain regulatory regions that control gene expression and the structure of chromosomes, yet these hypotheses were difficult to study in past years as diagnostic technology was developing.

"Only in recent years, with the sequencing of the entire transcriptome complete, have we realized how many RNA species are actually present. So, that raises the whole new question: if they aren't making the proteins - the work horses of the cell - then what are they doing?" said Mackay, director of Clemson University's Center for Human Genetics (CHG), which is part of the College of Science.

For Mackay and Anholt, also of the CHG, these human genetics questions can be probed by studying the common fruit fly, Drosophila melanogaster. Because many genes are conserved between humans and fruit flies, findings revealed by analyzing the Drosophila genome can be extrapolated to human health and disease.

Mackay and Anholt's former postdoctoral researchers, Logan Everett and Wen Huang, led the charge on this latest research, which identified more than 4,500 new transcripts in Drosophila that have never been uncovered before. Referred to by the researchers as "novel transcribed regions," these 4,500 transcripts consist primarily of noncoding RNAs that appear to be involved in regulating networks of genes and that could contribute to genetic disorders.

"Most disease-causing mutations are known to occur in the protein-coding portion of the genome, known as the exome, but when you're only sequencing the exome, you miss other disease-related factors in other parts of the genome, such as these long noncoding RNAs," said Anholt, Provost's Distinguished Professor of Genetics and Biochemistry at Clemson University. "Now that the cost of whole genome sequencing has gone down considerably, and we have the capability of sequencing whole genomes rapidly, we can look at elements of the genome that have traditionally been considered unimportant, and we can identify among them potential disease-causing elements that have never been seen before."

By probing several hundred inbred Drosophila fly lines, each containing individuals that are virtually genetically identical, the researchers discovered that many of the novel long noncoding RNAs regulate genes in heterochromatin, a tightly packed form of DNA in the genome that is usually considered "silent." Because heterochromatin is so condensed, it was thought to be inaccessible to the molecular machinery that transcribes DNA into RNA. Thus, any genes contained within heterochromatin are kept off, silent and unexpressed - or are they?

"What we think is that the repression of gene expression in heterochromatin is somewhat leaky, and that there is variation in how those genes are repressed," Mackay said. "The network of RNAs we've discovered may have to do with actually regulating chromatin state."

"These noncoding RNAs may play an important role in opening up such regions of the genome for expression of genes in a way that varies among different individuals depending on their genetic background," Anholt added.

Another outcome of the study is the expression of "jumping genes," known as transposons, that are pieces of DNA able to move around the genome. As transposons cut and paste into other genes, they may cause genome instability that leads to cancer, neurodegenerative disorders and other diseases.

These transposons were also located in heterochromatin, but the identification of transcripts of these transposons shows that they are actually being expressed, despite residing in a usually silent portion of the genome. Identifying regulators of transposable elements, as the researchers found among these 4,500 "novel transcribed regions," could prove useful in treating disorders that stem from transposon interference.

Overall, the study lends toward a greater understanding of gene regulatory networks that contribute to human health and disease.

"These observations open up an entirely new area of biology that hasn't been explored and has unlimited potential for future follow-up," Anholt said.

The team's own follow-up studies are using CRISPR gene editing technology to uncover what happens when genes revealed by this study are altered or deleted from the Drosophila genome. If the expression of other genes is altered by knocking one out, important conclusions can be drawn about the role that deleted gene plays in development or progression of disease.

ITHACA, N.Y. - A new two-step technique to repair herniated discs uses hyaluronic acid gel to re-inflate the disc and collagen gel to seal the hole, essentially repairing ruptured discs like you'd repair a flat tire.

After a rupture, a jelly-like material leaks out of a herniated disc, causing inflammation and pain. The injury is usually treated one of two ways: a surgeon sews up the hole, leaving the disc deflated; or the disc is refilled with a replacement material, which doesn't prevent repeat leakages. Each approach on its own isn't always effective.

A collaboration led by Cornell University professor Lawrence Bonassar combined these two methods into a new two-step technique that results in a "patched" disc that maintains mechanical function and won't collapse or deteriorate.

"This is really a new avenue and a whole new approach to treating people who have herniated discs," Bonassar said.

"We now have potentially a new option for them, other than walking around with a big hole in their intervertebral disc and hoping that it doesn't re-herniate or continue to degenerate. And we can fully restore the mechanical competence of the disc."

Bonassar's research group seeks engineering-based solutions for degenerative disc disease. Over the last decade, the group has developed a collagen gel that incorporates riboflavin, a photoactive vitamin B derivative. Instead of sewing up a ruptured disc, the researchers can patch it by applying their gel and shining light on it to activate the riboflavin.

The resulting chemical reaction causes fibers in the collagen to bond together and the thick gel stiffens into a solid. Most importantly, the gel provides a more fertile ground for cells to grow new tissue, sealing the defect better than any suture could.

The technique only takes five or 10 minutes and can be applied in conjunction with a discectomy, the hourlong procedure by which the leaked nucleus pulposus is removed from the nerve root. The technique could be used to address other types of disc degeneration, or integrated into other spinal procedures and therapies.

In a new peer-reviewed publication, University of Illinois at Chicago researchers describe how the body's response to inflammation, which helps to fight many kinds of infections, also can counterproductively suppress much-needed cell repair and regeneration in blood vessels.

In the study, which is published in Immunity, the researchers describe an enzyme that blocks the ability of blood vessel cells to self-heal. By studying mice with sepsis -- a condition caused when the body's inflammatory response to a bloodstream bacterial infection spirals out of control -- they found that removal of the enzyme allows cells to fully regenerate.

"When cells are faced with an injury or an infection, it seems that they make a 'fight' or 'fix' choice," said UIC's Asrar Malik, senior author of the study and the Schweppe Family Distinguished Professor and head of pharmacology at the College of Medicine. "Inflammation is the 'fight' response, and the cells appear to delay regeneration while amplifying the inflammatory response."

"We think that over time cells have evolved to favor fighting an infection over repairing damaged cells, but in some cases, this preference to fight puts the body at further risk," said Dr. Jalees Rehman, co-senior author and UIC professor of medicine, pharmacology and bioengineering at the College of Medicine. "Especially when the immune response of the body to an infection is so excessive that it damages vital organs such as the lungs, it is absolutely vital that we learn how to help cells restore their ability to regenerate and resolve the inflammation."

Rehman said that the enzyme -- named cGAS -- acts as a DNA sensor that is being activated by the DNA released by damaged mitochondria of the blood vessel cells.

"We showed that when the sensor is removed, blood vessel endothelial cells shift their balance towards restoration and regeneration," Rehman said.

In an experimental model of bacterial sepsis, mice lacking this DNA sensor had much higher rates of survival and showed rapid regeneration of the blood vessels in the lung.

"It's possible that the degree to which this DNA injury sensor gets activated contributes to why some individuals survive a severe condition like sepsis," he said. "Suppression of regeneration is especially concerning in the elderly. Our study suggests that further study of this DNA sensor might provide provocative new areas for research to improve endogenous regeneration."

EVANSTON, Ill. -- Every year, 15 million babies are born too early, with 1 million never making it to their next birthday. And in low-resource settings, the outlook is even more dire. Half of babies born at 32 weeks or earlier will die; whereas in high-resource settings, almost all of these babies survive.

To help bridge this gap, an interdisciplinary team of Northwestern University researchers has developed a new wireless, battery-charged, affordable monitoring system for newborn babies that can easily be implemented to provide clinical-grade care in nearly any setting.

The new devices also exceed the capabilities of existing, wired monitoring technologies to provide information beyond traditional vital signs, including crying, movement, body orientation and heart sounds. These soft, flexible sensors also are far gentler on newborns' fragile skin, and their wireless capabilities allow for more skin-to-skin contact with parents.

Not only can this technology lower risks by monitoring premature babies, it can also is monitor pregnant women during labor to ensure a healthy and safe delivery and reduce risks of maternal mortality. By closely monitoring the most vulnerable patients, physicians can be alerted to intervene before the infant or mother become seriously ill.

Details about the technology will be published March 11 in the journal Nature Medicine, with extensive tests on newborns at Ann & Robert H. Lurie Children's Hospital of Chicago and Prentice Women's Hospital in Chicago. The sensors described in the paper also are now being tested on newborns at Aga Khan University Hospital Nairobi, Kenya and on pregnant mothers in the University Teaching Hospital in Lusaka, Zambia.

'From the hospital to the home to the field'

Led by Northwestern's John A. Rogers, a pioneer in the emerging field of bio-integrated electronics, the research team developed the sensors last year and tested them on babies in the United States. Now, with support from the Bill & Melinda Gates Foundation and Save the Children, his team is deploying the devices internationally, starting with hospitals in Ghana, India, Kenya and Zambia.

"We designed our technology to offer affordable, clinical-grade monitoring capabilities for use anywhere in the world -- from the hospital to the home to the field," Rogers said. "Using advanced concepts in soft electronics, we achieved devices that are safe, easy to use and patient-centric. We included in our research a focus on features to allow application in low-resource settings in the developing world, where this type of technology has the greatest potential to improve and possibly save lives."

"The new technology represents a monumental advance in neonatal and pediatric care," said Dr. Debra Weese-Mayer, a pediatrician in autonomic medicine at Northwestern University Feinberg School of Medicine, who co-led the study with Rogers. "This is not strictly about making critical care systems 'wireless', this is about thinking expansively about what non-traditional variables we need to incorporate to more fully study health and ensure stability."

Rogers is the Louis Simpson and Kimberley Querrey Professor of Materials Science and Engineering and Biomedical Engineering in Northwestern's McCormick School of Engineering and professor of neurological surgery in Feinberg. He also is executive director of the Querrey Simpson Institute for Bio-electronics at Northwestern. Weese-Mayer is the Beatrice Cummings Mayer Professor of Pediatric Autonomic Medicine at Feinberg and chief of pediatric autonomic medicine at Lurie Children's Hospital.

Reliable in areas without stable power

The new study builds on previous research conducted in the Rogers lab. Last February, Rogers and his collaborators published results from a study conducted at Lurie Children's Hospital and Prentice Women's Hospital in Chicago. Here, researchers tested a pair of wireless, battery-free, flexible sensors on premature babies. The sensors proved to be as precise and accurate as traditional wire-based monitoring devices that interfere with parent-baby cuddling and physical bonding.

To move these platforms from Chicago into the developing world, Rogers' team added a small, thin, rechargeable battery to give the device stable, reliable power for operation in rural settings and to improve the wireless operating range. The team also added extra sensing capabilities to monitor crying, movement and heart sounds.

"We couldn't just drop our existing technology into other countries and different settings without taking their specific needs into account," Rogers said. "We wanted to understand the broader landscape and to develop a technology that is easy-to-use, helpful and practical. We knew that we needed to build the foundations for highly robust, reusable devices, applicable in regions with limited facilities and resources."

"Some areas experience rolling blackouts every day and uneven internet coverage," said Dr. Shuai (Steve) Xu, a Northwestern Medicine dermatologist and co-first author of the study who leads deployment of the system on the ground. "People in these areas need a practical device that works and is cheaper to manufacture."

Sensors send data to mobile devices

The sensors use radio frequencies to wirelessly transmit data from the baby to nurses' station displays. They also can send data directly to a smartphone or tablet.

"The beauty of the technology is that it can operate with a wide range of mobile devices without sacrificing accuracy, relative to the most sophisticated systems used in hospitals today," Xu said. "You don't need expensive equipment that requires a specialized bioengineer and I.T. department to install. You pull out your mobile device, connect to our sensors, and you're taking care of patients."

Implementing technology abroad

Xu, the medical director of the Querrey Simpson Institute for Bio-electronics, assistant professor of dermatology and pediatrics at Feinberg and assistant professor of biomedical engineering at McCormick, has spent the past six months leading a team of engineers in setting up the technology in hospitals in Kenya and Zambia, working with nurses and physicians. The program will involve testing the sensors on 15,000 pregnant women and 500 newborn babies by mid-2021.

"This is a collaborative team effort," Xu said. "We've spent a lot of time working with and listening to physicians, nurses and health care workers in each location. We want to make sure that our technology is useful and helps solve problems they face every day. It's been incredibly motivating."

So far, 42 babies in Kenya have worn the wireless sensors alongside gold-standard, traditional monitoring systems so researchers could do a side-by-side, quantitative comparison. After validating the device at Aga Khan University Hospital, the team plans to move the technology to low-resource hospitals in rural Africa, where the need is greatest.

"The urgency of need in Nairobi is significant, but nothing compared to that in the rural areas," Rogers said. "There's room for improvement everywhere, but the added value of making affordable health care monitoring systems is so much higher in these settings."

Collaborating with nurses abroad

Rogers and Xu said the early feedback from hospital nurses has been invaluable. The sensors work in pairs -- one on the chest and one wrapped around a foot. In an earlier version of the technology, nurses worried that the chest sensor might be too large for small, fragile newborns. Rogers and his team immediately responded to this feedback to make a smaller, thinner chest device.

"The nurses have been enthusiastic about the new iteration," Rogers said. "These latest platforms also are giving us great data. When we put the sensor on the baby, it starts working immediately, in nearly any setting or location."

Nurses also have struggled with perfecting the foot sensor's alignment. If the sensor is not correctly wrapped around the foot, then the data are not as accurate.

"It takes some practice to quickly align the foot sensor," Rogers said. "So we designed a system that lights up as red, yellow or green -- incorrect, close or in the right place -- depending on the accuracy of the alignment, to provide feedback to the caregiver."

'Mothers love our sensors'

The team also has received encouraging feedback from parents, who benefit from more physical bonding or "kangaroo care." Dennis Ryu, a Ph.D. student in the Rogers lab, spent six weeks on the ground at Aga Khan University Hospital in Nairobi, Kenya and University Teaching Hospital in Lusaka, Zambia with plans to return this spring.

"Mothers love our sensors because they can have more skin-to-skin contact with their babies," Ryu said. "Kangaroo care has profound benefits for the mother and baby, including bonding, better sleep and less stress."

"Suggestions come directly from speaking to people on the ground and directly observing how our sensors are used," Xu added. "It really is a bi-directional information flow."

What's next?

With an exclusive license to the technology from Northwestern, Rogers and Xu launched Sibel Health to scale the technology and to earn FDA approval later this year, with a focus on maternal, fetal, neonatal and pediatric health. More recently, Sibel announced a strategic partnership with Dräger, a leading international safety and medical technology company that focuses on products that protect, support and save lives.

Next, Rogers and Xu plan to incorporate artificial intelligence into the sensors to extract insights from the data and provide health care professionals with recommendations for care.

"These systems are generating half a gigabyte of data for one patient a day. That's a lot of physiological information," Xu said. "We'd like to use clinically validated algorithms that could, for example, tell us if a baby is likely to develop sepsis within the next 24 hours based on their vital signals. Then we could have ventilators and antibiotics ready to escalate care almost proactively. For pregnant women, we're working with Dr. Jeffrey Stringer -- the director of the division of Global Women's Health at University of North Carolina at Chapel Hill -- with funding from the Bill & Melinda Gates Foundation to more quickly identify danger signals in low-resource settings."

Rogers estimates these new wireless sensors could appear in U.S. hospitals within the next year. His team also expects to send sensors to more hospitals in countries around the world as part of an ongoing international effort to improve affordable health care monitoring.

"We believe that our technology could significantly enhance the quality of neonatal care around the world," Rogers said. "We think in terms of a 'NICU of the future,' available anywhere."

"The vision is bold," Xu said. "We want to see these sensors in every country, monitoring the first heartbeat to the last in our most vulnerable patients."

What The Study Did: Researchers used French electronic health data to investigate how risk of colorectal cancer compared among obese adults who had weight-loss surgery and who didn't.

Authors: Laurent Bailly, M.D., Ph.D., Universite Cote d'Azur, Nice, France, and coauthors.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamasurg.2020.0089)

Editor's Note: Please see the articles for additional information, including other authors, author contributions and affiliations, conflicts of interest and financial disclosures, and funding and support.

The ability of crocodiles to survive mass extinctions could be in part due to their more hands-on approach to parenting, say scientists at the University of Bath's Milner Centre for Evolution.

Crocodiles are one of the oldest surviving lineages on Earth, having survived two extinctions - the mass extinction in the late Cretaceous period that killed the dinosaurs 66 million years ago, and another smaller extinction event in the Eocene period 33.9 million years ago that wiped out huge numbers of marine and other aquatic life.

The reasons for their remarkable resilience to extinctions are poorly understood. Previous studies have suggested that diet, their aquatic nature, and behaviours that help them cope with harsh environmental conditions all factor in their ability to survive.

A new study published in the Biological Journal of the Linnean Society suggests that crocodiles' unique reproductive biology may also play a part.

Similar to their turtle relatives, crocodylians have no sex chromosomes; instead the sex of hatchlings is determined by the temperature at which they are incubated. Each of these species has a threshold temperature at which the ratio of males to females is roughly equal.

For crocodylians, the higher the temperature, the more males are produced. For turtles, the reverse is true. Climate change is already causing some turtle populations to become over 80% female, which in the future could lead to devastating consequences for their populations. The researchers wanted to determine whether there was a similar effect on crocodylian species.

The scientists analysed data from 20 different species of crocodiles from across the world to see the relationship between their latitude and a variety of characteristics including body size and reproductive data including egg mass, clutch size and incubation temperature.

They found (with some notable exceptions) that smaller species tend to live at latitudes close to the equator, with larger species generally living in temperate climes in the higher latitudes. More surprisingly, they found that, in contrast to turtles, the threshold incubation temperatures don't correlate with the latitude.

Whilst turtles are critically endangered by the increase in temperatures due to climate change, this study suggests crocodiles may be slightly more resilient because of the ways they look after their young.

Turtles always return to the same beach to nest and lay eggs regardless of the local environmental conditions, leaving their young to hatch alone and fend for themselves.

The authors suggest that the geographical location doesn't affect the incubation temperatures as much as in turtles because crocodiles select their nesting sites carefully and bury their nests in rotting vegetation or earth which insulates them against temperature fluctuations.

However, crocodiles are still threatened by other human activities and some species will likely succumb to the current mass extinction faced by the planet.

Rebecca Lakin, first author of the study and PhD student at the Milner Centre for Evolution at the University of Bath, said: "Crocodylians are keystone species in their ecosystems. They are the last surviving archosaurs, a group that once inhabited every continent and has persisted for at least 230 million years.

"They show a remarkable resilience to cataclysmic climate change and habitat loss, however half of all living crocodile species are threatened with extinction and the rate of vertebrate species loss will soon equal or even exceed that of the mass extinction that killed the dinosaurs.

"Whilst their parenting skills and other adaptations brace them for climate change, they aren't immune. They are still vulnerable to other human-induced threats such as pollution, the damming of rivers, nest flooding and poaching for meat or skin.

"Climate change could encourage these great survivors to relocate to other areas that are close to densely human populated areas, putting them at even greater threat."