Culture

New research, based on earlier results in mice, suggests that our brains are never at rest, even when we are not learning anything about the world around us.

Our brains are often likened to computers, with learned skills and memories stored in the activity patterns of billions of nerve cells. However, new research shows that memories of specific events and experiences may never settle down. Instead, the activity patterns that store information can continually change, even when we are not learning anything new.

Why does this not cause the brain to forget what it has learned? The study, from the University of Cambridge, Harvard Medical School and Stanford University, reveals how the brain can reliably access stored information despite drastic changes in the brain signals that represent it.

The research, led by Dr Timothy O'Leary from Cambridge's Department of Engineering, shows that different parts of our brain may need to relearn and keep track of information in other parts of the brain as it moves around. Their study, published in the open access journal eLife, provides some of the first evidence that constant changes in neural activity are compatible with long term memories of learned skills.

The researchers came to this conclusion through modelling and analysis of data taken from an experiment in which mice were trained to associate a visual cue at the start of a 4.5-metre-long virtual reality maze with turning left or right at a T-junction, before navigating to a reward. The results of the 2017 study showed that single nerve cells in the brain continually changed the information they encoded about this learned task, even though the behaviour of the mice remained stable over time.

The experimental data consisted of activity patterns from hundreds of nerve cells recorded simultaneously in a part of the brain that controls and plans movement, recorded at a resolution that is not yet possible in humans.

"Finding coherent patterns in this large assembly of cells is challenging, much like trying to determine the behaviour of a swarm of insects by watching a random sample of individuals," said O'Leary. "However, in some respects the brain itself needs to solve a similar task, because other brain areas need to extract and process information from this same population."

Nerve cells connect to hundreds or even thousands of their neighbours and extract information by weighting and pooling it. This has a direct analogy with the methods used by pollsters in the run up to an election: survey results from multiple sources are collected and 'weighted' according to their consistency. In this way a steady pattern can emerge even when individual measurements vary wildly.

The Cambridge group used this principle to construct a decoding algorithm that extracted consistent, hidden patterns within the complex activity of hundreds of cells. They found two things. First, that there was indeed a consistent hidden pattern that could accurately predict the animal's behaviour. Second, this consistent pattern itself gradually changes over time, but not so drastically that the decoding algorithm couldn't keep up. This suggests that the brain continually modifies the internal code that relays information between different internal circuits.

Science fiction explores the possibility of transferring our memories and experiences into hardware devices directly from our brains. If future technology eventually allows us to upload and download our thoughts and memories, we may find that our brain cannot interpret its own activity patterns if they are replayed many years later. The concept of an apple - its colour, flavour, taste and the memories associated with it - may remain consistent, but the patterns of activity it evokes in the brain may change completely over time.

Such conundra will likely remain speculative for the immediate future, but experimental technology that achieves a limited version of such mind reading is already a reality, as this study shows. Brain-machine interfaces are a rapidly maturing technology, and human neural interfaces that can control prosthetics and external hardware have been in clinical use for over a decade. The work from the Cambridge group highlights a major open challenge in extracting reliable information from the brain.

"Even though we can now monitor brain activity and relate it directly to memories and experiences, the activity patterns themselves continually change over a period of several days," said O'Leary, who is a Lecturer in Information Engineering and Medical Neuroscience. "Our study shows that in spite of this change, we can construct and maintain a relatively stable 'dictionary' to read out what an animal is thinking as it navigates a familiar environment.

"The work suggests that our brains are never at rest, even when we are not learning anything about the external world. This has major implications for our understanding of the brain and for brain-machine interfaces and neural prosthetics."

Educators could use the COVID-19 outbreak to help middle-schoolers better understand the world, according to new research from faculty at Binghamton University, State University of New York.

In the field of middle-grades education (grade 4-9), the COVID-19 pandemic may offer educators a perfect real-world scenario that invites students to critically examine how our global community's actions impact one another, according to Bogum Yoon, associate professor of literacy education at Binghamton University.

"The outbreak of the coronavirus has affected individuals' lives and education around the world, including the United States," said Yoon. "This phenomenon invites educators to work with students for deepening their understanding about the interconnected world as global citizens."

In her new paper, Yoon provides instructional suggestions on how educators can use the pandemic crisis as an authentic world-learning opportunity. The suggestions could naturally tie into several content areas: English language arts (e.g., reading about the virus and discussing it; critiquing news media content on the coronavirus); science (e.g., the nature of the coronavirus and its impact for individuals' health; discussing the impact of masks for their own and others' health); social studies (e.g., virus impact to different ethnic and SES groups; the restriction of individuals' rights and freedom under a ban); and mathematics (e.g., comparing U.S. death rates with other countries through graphs; reviewing the statistics on the shortage of essential goods in a given country and comparing them with other countries). Although Yoon focused on middle grade education, these instructional suggestions can be applied to any grade level.

"The topic of the novel disease provides an excellent opportunity to recognize the global issue, extend school curriculum, and examine the role of the world," said Yoon. "Through the process of learning about the world, students can better understand their own identities, ideologies and situations."

The paper, "The Global Pandemic as Learning Opportunities about the World: Extending School Curriculum," was published in Middle Grades Review.

Young gay sexual minority men - especially Black and Latino youth - have their first sexual experiences at younger ages, emphasizing a need for comprehensive and inclusive sex education, according to Rutgers researchers.

The study, published in the Journal of Sex Research, examined consensual sex behaviors to better understand same-sex sexual debut, or the age at which people first engage in sexual behaviors.

The researchers, part of the Rutgers School of Public Health's Center for Health, Identity, Behavior and Prevention Studies (CHIBPS), found that 19 percent of participants had their first sexual experience before the age of 13.

The researchers also found that same-sex sexual encounters first happen, on average, at 14.5 years, with Hispanic/Latinx and Black non-Hispanic participants reporting a younger age for their first time performing oral sex or engaging in anal sex, compared to their peers.

Earlier age of sexual debut among sexual minority men is associated with a range of sexual and health risk behaviors, including increased likelihood of condomless sex; tobacco, alcohol, and other substance use; psychological distress; suicidality; and earlier age of HIV diagnosis.

According to the researchers, health care providers, including pediatricians and behavioral health therapists, can help reduce potential harms of these behaviors by having candid conversations about sex; not assuming the sexual identities or behaviors of their young patients; actively inquiring about sexual behaviors with partners of all genders; providing appropriate counseling about all sexual behaviors and their associated risks for HIV and other STIs; and speaking with adolescent patients in private - without parents/guardians present - whenever legally and ethically possible.

Providers working with young gay men of all ages should also consider beginning routine testing for HIV and other sexually transmitted diseases at earlier ages than previously indicated, particularly among youth of color.

"Our results suggest that health care providers can play an active role in mitigating sexual and health behaviors that are associated with the early onset of same-sex sexual behaviors; to date the medical profession is ill equipped to address the needs of LGBTQ+ people," said Perry N. Halkitis, dean of the Rutgers School of Public Health.

Comprehensive sexuality education, which is inclusive of sexual and gender minority populations and all types of sexual behaviors, may not only empower sexual and gender minority youth to make informed choices about their sexual health and behavior, but may also improve school climate through educating non-LGBTQ peers.

"As many schools are forced to redesign their classrooms and curricula to accommodate socially distanced or remote learning for COVID-19, this may be the perfect time to consider implementing comprehensive sex education programming to provide age-appropriate sexual health education for people of all genders and sexual orientations," said Caleb LoSchiavo, doctoral student at the Rutgers School of Public Health and co-author.

Vertical farms with their soil-free, computer-controlled environments may sound like sci-fi. But there is a growing environmental and economic case for them, according to new research laying out radical ways of putting food on our plates.

The interdisciplinary study combining biology and engineering sets down steps towards accelerating the growth of this branch of precision agriculture, including the use of aeroponics which uses nutrient-enriched aerosols in place of soil.

Carried out by the John Innes Centre, the University of Bristol and the aeroponic technology provider LettUs Grow, the study identifies future research areas needed to accelerate the sustainable growth of vertical farming using aeroponic systems.

Dr Antony Dodd, a group leader at the John Innes Centre and senior author of the study, says: "By bringing fundamental biological insights into the context of the physics of growing plants in an aerosol, we can help the vertical farming business become more productive more quickly, while producing healthier food with less environmental impact."

Jack Farmer, Chief Scientific Officer at LettUs Grow and one of the authors of the study, adds: "Climate change is only going to increase the demand for this technology. Projected changes in regional weather patterns and water availability are likely to impact agricultural productivity soon. Vertical farming offers the ability to grow high value nutritious crops in a climate resilient manner all year round, proving a reliable income stream for growers."

Vertical farming is a type of indoor agriculture where crops are cultivated in stacked systems with water, lighting and nutrient sources carefully controlled.

It is part of a rapidly growing sector supported by artificial intelligence in which machines are taught to manage day to day horticultural tasks. The industry is set to grow annually by 21% by 2025 according to one commercial forecast (Grand View Research, 2019).

Green benefits include better use of space because vertical farms can be sited in urban locations, fewer food miles, isolation from pathogens, reduction in soil degradation and nutrient and water recapturing and recycling.

Vertical farms also allow product consistency, price stabilization, and cultivation at latitudes incompatible with certain crops such as the desert or arctic.

"Vertical systems allow us to extend the latitude range on which crops can be grown on the planet, from the deserts of Dubai to the 4-hour winter days of Iceland. In fact, if you were growing crops on Mars you would need to use this kind of technology because there is no soil," says Dr Dodd.

The study, which appears in the journal New Phytologist, lays out seven steps - strategic areas of future research needed to underpin increased productivity and sustainability of aeroponic vertical farms.

These seek to understand:

Why aeroponic cultivation can be more productive than hydroponic or soil cultivation.

The relationship between aeroponic cultivation and 24-hour circadian rhythms of plants.

Root development of a range of crops in aeroponic conditions.

The relationship between aerosol droplet size and deposition and plant performance.

How we can establish frameworks for comparing vertical farming technologies for a range of crops.

How aeroponic methods affect microbial interactions with plant roots.

The nature of recycling of root exudates (fluids secreted by the roots of plants) within the nutrient solutions of closed aeroponic systems.

The report argues that a driver of technological innovation in vertical farms is minimizing operation costs whilst maximizing productivity - and that investment in fundamental biological research has a significant role.

Dr Dodd's research area covers circadian rhythms - biological clocks which align plant physiology and molecular processes to the day to day cycle of light and dark. He recently completed a year-long Royal Society Industry Fellowship with LettUs Grow.

This involved combining Dr Dodd's expertise in circadian rhythms and plant physiology with the work of LettUs Grow's team of biologists and engineers to design optimal aeroponic cultivation regimens. This is a key area of investigation as these molecular internal timers will perform differently in vertical farms.

Aeroponic platforms are often used to grow high value crops such as salads, pak choi, herbs, small brassica crops, pea shoots and bean shoots. LettUs Grow are also working on growth regimens for fruiting and rooting crops such as strawberries and carrots, as well as aeroponic propagation of trees for both fruit and forestry.

John Innes Centre researchers have bred a line of broccoli adapted to grow indoors for a major supermarket and one of the aims of research will be to test how we can genetically tune more crops to grow in the controlled space of vertical farms.

Bethany Eldridge, a researcher at the University of Bristol studying root-environment interactions and first author of the study adds: "Given that 80% of agricultural land worldwide is reported to have moderate or severe erosion, the ability to grow crops in a soilless system with minimal fertilizers and pesticides is advantageous because it provides an opportunity to grow crops in areas facing soil erosion or other environmental issues such as algal blooms in local water bodies that may have been driven by traditional, soil-based, agriculture."

Lilly Manzoni, Head of Research and Development at LettUs Grow and one the authors of the study says, "This paper is unique because it is broader than a typical plant research paper, it combines the expertise of engineers, aerosol scientists, plant biologists and horticulturalists. The wonderful thing about controlled environment agriculture and aeroponics is that it is truly interdisciplinary"

An exploding white dwarf star blasted itself out of its orbit with another star in a 'partial supernova' and is now hurtling across our galaxy, according to a new study from the University of Warwick.

It opens up the possibility of many more survivors of supernovae travelling undiscovered through the Milky Way, as well as other types of supernovae occurring in other galaxies that astronomers have never seen before.

Reported today (15 July) in Monthly Notices of the Royal Astronomical Society the research, funded by the Leverhulme Trust and Science and Technology Facilities Council (STFC), analysed a white dwarf that was previously found to have an unusual atmospheric composition. It reveals that the star was most likely a binary star that survived its supernova explosion, which sent it and its companion flying through the Milky Way in opposite directions.

White dwarfs are the remaining cores of red giants after these huge stars have died and shed their outer layers, cooling over the course of billions of years. The majority of white dwarfs have atmospheres composed almost entirely of hydrogen or helium, with occasional evidence of carbon or oxygen dredged up from the star's core.

This star, designated SDSS J1240+6710 and discovered in 2015, seemed to contain neither hydrogen nor helium, composed instead of an unusual mix of oxygen, neon, magnesium and silicon. Using the Hubble Space Telescope, the scientists also identified carbon, sodium, and aluminium in the star's atmosphere, all of which are produced in the first thermonuclear reactions of a supernova.

However, there is a clear absence of what is known as the 'iron group' of elements, iron, nickel, chromium and manganese. These heavier elements are normally cooked up from the lighter ones, and make up the defining features of thermonuclear supernovae. The lack of iron group elements in SDSSJ1240+6710 suggests that the star only went through a partial supernova before the nuclear burning died out.

The scientists were able to measure the white dwarf's velocity and found that it is travelling at 900,000 kilometres per hour. It also has a particularly low mass for a white dwarf - only 40% the mass of our Sun - which would be consistent with the loss of mass from a partial supernova.

Lead author Professor Boris Gaensicke from the Department of Physics at the University of Warwick said: "This star is unique because it has all the key features of a white dwarf but it has this very high velocity and unusual abundances that make no sense when combined with its low mass.

"It has a chemical composition which is the fingerprint of nuclear burning, a low mass and a very high velocity: all of these facts imply that it must have come from some kind of close binary system and it must have undergone thermonuclear ignition. It would have been a type of supernova, but of a kind that that we haven't seen before."

The scientists theorise that the supernova disrupted the white dwarf's orbit with its partner star when it very abruptly ejected a large proportion of its mass. Both stars would have been carried off in opposite directions at their orbital velocities in a kind of slingshot manoeuvre. That would account for the star's high velocity.

Professor Gaensicke adds: "If it was a tight binary and it underwent thermonuclear ignition, ejecting quite a lot of its mass, you have the conditions to produce a low mass white dwarf and have it fly away with its orbital velocity."

The best studied thermonuclear supernovae are the "Type Ia", which led to the discovery of dark energy, and are now routinely used to map the structure of the Universe. But there is growing evidence that thermonuclear supernovae can happen under very different conditions.

SDSSJ1240+6710 may be the survivor of a type of supernova that hasn't yet been "caught in the act". Without the radioactive nickel that powers the long-lasting afterglow of the Type Ia supernovae, the explosion that sent SDSS1240+6710 hurtling across our Galaxy would have been a brief flash of light that would have been difficult to discover.

Professor Gaensicke adds: "The study of thermonuclear supernovae is a huge field and there's a vast amount of observational effort into finding supernovae in other galaxies. The difficulty is that you see the star when it explodes but it's very difficult to know the properties of the star before it exploded.

"We are now discovering that there are different types of white dwarf that survive supernovae under different conditions and using the compositions, masses and velocities that they have, we can figure out what type of supernova they have undergone. There is clearly a whole zoo out there. Studying the survivors of supernovae in our Milky Way will help us to understand the myriads of supernovae that we see going off in other galaxies."

Professor S.O. Kepler of Universidade Federal do Rio Grande do Sul, Brazil, and who originally discovered this star, said: "The fact that such a low mass white dwarf went through carbon burning is a testimony of the effects of interacting binary evolution and its effect on the chemical evolution of the Universe."

Dr Roberto Raddi of Universitat Politècnica de Catalunya, Spain, who carried out the kinematic analysis, said: "Once again, the synergy between very precise Gaia astrometry and spectroscopic analysis have helped to constrain the striking properties of a unique white dwarf, which probably formed in a thermonuclear supernova and was ejected at high velocity as consequence of the explosion."

World's population likely to shrink after mid-century, forecasting major shifts in global population and economic power - new analysis, published in The Lancet forecasts global, regional, and national populations, mortality, fertility, and migration for 195 countries worldwide.

The USA is projected to have population growth until just after mid-century (364 million in 2062), followed by a moderate decline of less than 10% to 336 million by 2100--the world's fourth most populous country.

The USA's total fertility rate--which represents the average number of children a woman delivers over her lifetime--is predicted to steadily decline from 1.8 in 2017 to 1.5 in 2100; well below the minimum birth rate (2.1) considered necessary to maintain existing population levels long-term without immigration.

In 2100, the USA is forecasted to have the fourth largest working-age population in the world (around 181 million), after India, Nigeria, and China (figure 8)--with immigration likely sustaining the US workforce, with the largest net immigration in absolute numbers (more than half a million more people are estimated to immigrate to the USA in 2100 than will emigrate out). However, the researchers warn that US liberal immigration policies have faced a political backlash in recent years, threatening the country's potential to sustain population and economic growth.

The forecasting model predicts that while the USA had the largest economy in 2017, China is set to replace it in 2035, but the USA is forecasted to once again become the largest economy in 2098--bolstered by immigration (figure 9). Among the 10 countries with the largest populations in 2017 or 2100, the USA is predicted to have the fifth highest life expectancy in 2100 (82.3 years), up from 78.4 in 2017 (appendix 2, section 3).

Please find below: 1) Media release, 2) Access to the Article + linked Comments 3) Country data 4) Infographics. For further information, please contact The Lancet press office (pressoffice@lancet.com)

By 2100, projected fertility rates in 183 of 195 countries will not be high enough to maintain current populations without liberal immigration policies.

World population forecasted to peak in 2064 at around 9.7 billion people and fall to 8.8 billion by century's end, with 23 countries seeing populations shrink by more than 50%, including Japan, Thailand, Italy, and Spain.

Dramatic declines in working age-populations are predicted in countries such as India and China, which will hamper economic growth and lead to shifts in global powers.

Liberal immigration policies could help maintain population size and economic growth even as fertility falls.

Authors warn response to population decline must not compromise progress on women's freedom and reproductive rights.

Improvements in access to modern contraception and the education of girls and women are generating widespread, sustained declines in fertility, and world population will likely peak in 2064 at around 9.7 billion, and then decline to about 8.8 billion by 2100--about 2 billion lower than some previous estimates [1], according to a new study published in The Lancet.

The modelling research uses data from the Global Burden of Disease Study 2017 to project future global, regional, and national population. Using novel methods for forecasting mortality, fertility, and migration, the researchers from the Institute for Health Metrics and Evaluation (IHME) at the University of Washington's School of Medicine estimate that by 2100, 183 of 195 countries will have total fertility rates (TFR), which represent the average number of children a woman delivers over her lifetime, below replacement level of 2.1 births per woman. This means that in these countries populations will decline unless low fertility is compensated by immigration.

The new population forecasts contrast to projections of 'continuing global growth' by the United Nations Population Division [1], and highlight the huge challenges to economic growth of a shrinking workforce, the high burden on health and social support systems of an ageing population, and the impact on global power linked to shifts in world population.

The new study also predicts huge shifts in the global age structure, with an estimated 2.37 billion individuals over 65 years globally in 2100, compared with 1.7 billion under 20 years, underscoring the need for liberal immigration policies in countries with significantly declining working age populations.

"Continued global population growth through the century is no longer the most likely trajectory for the world's population", says IHME Director Dr. Christopher Murray, who led the research. "This study provides governments of all countries an opportunity to start rethinking their policies on migration, workforces and economic development to address the challenges presented by demographic change." [2]

IHME Professor Stein Emil Vollset, first author of the paper, continues, "The societal, economic, and geopolitical power implications of our predictions are substantial. In particular, our findings suggest that the decline in the numbers of working-age adults alone will reduce GDP growth rates that could result in major shifts in global economic power by the century's end. Responding to population decline is likely to become an overriding policy concern in many nations, but must not compromise efforts to enhance women's reproductive health or progress on women's rights." [2]

Dr Richard Horton, Editor-in-Chief, The Lancet, adds: "This important research charts a future we need to be planning for urgently. It offers a vision for radical shifts in geopolitical power, challenges myths about immigration, and underlines the importance of protecting and strengthening the sexual and reproductive rights of women. The 21st century will see a revolution in the story of our human civilisation. Africa and the Arab World will shape our future, while Europe and Asia will recede in their influence. By the end of the century, the world will be multipolar, with India, Nigeria, China, and the US the dominant powers. This will truly be a new world, one we should be preparing for today." [2]

Accelerating decline in fertility worldwide

The global TFR is predicted to steadily decline, from 2.37 in 2017 to 1.66 in 2100--well below the minimum rate (2.1) considered necessary to maintain population numbers (replacement level)-- with rates falling to around 1.2 in Italy and Spain, and as low as 1.17 in Poland.

Even slight changes in TFR translate into large differences in population size in countries below the replacement level--increasing TFR by as little as 0.1 births per woman is equivalent to around 500 million more individuals on the planet in 2100.

Much of the anticipated fertility decline is predicted in high-fertility countries, particularly those in sub-Saharan Africa where rates are expected to fall below the replacement level for the first time--from an average 4.6 births per woman in 2017 to just 1.7 by 2100. In Niger, where the fertility rate was the highest in the world in 2017--with women giving birth to an average of seven children--the rate is projected to decline to around 1.8 by 2100.

Nevertheless, the population of sub-Saharan Africa is forecast to triple over the course of the century, from an estimated 1.03 billion in 2017 to 3.07 billion in 2100--as death rates decline and an increasing number of women enter reproductive age. North Africa and the Middle East is the only other region predicted to have a larger population in 2100 (978 million) than in 2017 (600 million).

Many of the fastest-shrinking populations will be in Asia and central and eastern Europe. Populations are expected to more than halve in 23 countries and territories, including Japan (from around 128 million people in 2017 to 60 million in 2100), Thailand (71 to 35 million), Spain (46 to 23 million), Italy (61 to 31 million), Portugal (11 to 5 million), and South Korea (53 to 27 million). An additional 34 countries are expected to have population declines of 25 to 50%, including China (1.4 billion in 2017 to 732 million in 2100; see table).

Huge shifts in global age structure - with over 80s outnumbering under 5s two to one

As fertility falls and life expectancy increases worldwide, the number of children under 5 years old is forecasted to decline by 41% from 681 million in 2017 to 401 million in 2100, whilst the number of individuals older than 80 years is projected to increase six fold, from 141 million to 866 million. Similarly, the global ratio of adults over 80 years to each person aged 15 years or younger is projected to rise from 0.16 in 2017 to 1.50 in 2100, in countries with a population decline of more than 25%.

Furthermore, the global ratio of non-working adults to workers was around 0.8 in 2017, but is projected to increase to 1.16 in 2100 if labour force participation by age and sex does not change.

"While population decline is potentially good news for reducing carbon emissions and stress on food systems, with more old people and fewer young people, economic challenges will arise as societies struggle to grow with fewer workers and taxpayers, and countries' abilities to generate the wealth needed to fund social support and health care for the elderly are reduced", says Vollset. [2]

Declining working-age populations could see major shifts in size of economies

The study also examined the economic impact of fewer working-age adults for all countries in 2017. While China is set to replace the USA in 2035 with the largest total gross domestic product (GDP) globally, rapid population decline from 2050 onward will curtail economic growth. As a result, the USA is expected to reclaim the top spot by 2098, if immigration continues to sustain the US workforce (figure 9).

Although numbers of working-age adults in India are projected to fall from 762 million in 2017 to around 578 million in 2100, it is expected to be one of the few – if only – major power in Asia to protect its working-age population over the century. It is expected to surpass China’s workforce population in the mid-2020s (where numbers of workers are estimated to decline from 950 million in 2017 to 357 million in 2100)—rising up the GDP rankings from 7th to 3rd (figure 8).

Sub-Saharan Africa is likely to become an increasingly powerful continent on the geopolitical stage as its population rises. Nigeria is projected to be the only country among the world’s 10 most populated nations to see its working-age population grow over the course of the century (from 86 million in 2017 to 458 million in 2100), supporting rapid economic growth and its rise in GDP rankings from 23rd place in 2017 to 9th place in 2100 (figure 8).

While the UK, Germany, and France are expected to remain in the top 10 for largest GDP worldwide at the turn of the century, Italy (from rank 9th in 2017 to 25th in 2100) and Spain (from 13th to 28th) are projected to fall down the rankings, reflecting much greater population decline (figure 9).

Liberal immigration could help sustain population size and economic growth

The study also suggests that population decline could be offset by immigration, with countries that promote liberal immigration better able to maintain their population size and support economic growth, even in the face of declining fertility rates.

The model predicts that some countries with fertility lower than replacement level, such as the USA, Australia, and Canada, will probably maintain their working-age populations through net immigration (see appendix 2 section 4). Although the authors note that there is considerable uncertainty about these future trends.

"For high-income countries with below-replacement fertility rates, the best solutions for sustaining current population levels, economic growth, and geopolitical security are open immigration policies and social policies supportive of families having their desired number of children", Murray says. "However, a very real danger exists that, in the face of declining population, some countries might consider policies that restrict access to reproductive health services, with potentially devastating consequences. It is imperative that women's freedom and rights are at the top of every government's development agenda." [2]

The authors note some important limitations, including that while the study uses the best available data, predictions are constrained by the quantity and quality of past data. They also note that past trends are not always predictive of what will happen in the future, and that some factors not included in the model could change the pace of fertility, mortality, or migration. For example, the COVID-19 pandemic has affected local and national health systems throughout the world, and caused over half a million deaths. However, the authors believe the excess deaths caused by the pandemic are unlikely to significantly alter longer term forecasting trends of global population.

Writing in a linked Comment, Professor Ibrahim Abubakar, University College London (UCL), UK, and Chair of Lancet Migration (who was not involved in the study) [3], says:"Migration can be a potential solution to the predicted shortage of working-age populations. While demographers continue to debate the long-term implications of migration as a remedy for declining TFR, for it to be successful, we need a fundamental rethink of global politics. Greater multilateralism and a new global leadership should enable both migrant sending and migrant-receiving countries to benefit, while protecting the rights of individuals. Nations would need to cooperate at levels that have eluded us to date to strategically support and fund the development of excess skilled human capital in countries that are a source of migrants. An equitable change in global migration policy will need the voice of rich and poor countries. The projected changes in the sizes of national economies and the consequent change in military power might force these discussions."

He adds: "Ultimately, if Murray and colleagues' predictions are even half accurate, migration will become a necessity for all nations and not an option. The positive impacts of migration on health and economies are known globally. The choice that we face is whether we improve health and wealth by allowing planned population movement or if we end up with an underclass of imported labour and unstable societies. The Anthropocene has created many challenges such as climate change and greater global migration. The distribution of working-age populations will be crucial to whether humanity prospers or withers."

WASHINGTON (July 14, 2020)--Silver strands and graying hair is a sign of aging in humans, but things aren't so simple for our closest ape relatives--the chimpanzee. A new study published today in the journal PLOS ONE by researchers at the George Washington University found graying hair is not indicative of a chimpanzee's age.

This research calls into question the significance of the graying phenotype in wild non-human species. While graying is among the most salient traits a chimpanzee has--the world's most famous chimpanzee was named David Greybeard--there is significant pigmentation variation among individuals. Graying occurs until a chimpanzee reaches midlife and then plateaus as they continue to age, according to Elizabeth Tapanes, a Ph.D. candidate in the GW Department of Anthropology and lead author of the study.

"With humans, the pattern is pretty linear, and it's progressive. You gray more as you age. With chimps that's really not the pattern we found at all," Tapanes said. "Chimps reach this point where they're just a little salt and peppery, but they're never fully gray so you can't use it as a marker to age them."

The researchers gathered photos of two subspecies of wild and captive chimpanzees from their collaborators in the field to test this observation. They visually examined photos of the primates, evaluated how much visible gray hair they had and rated them accordingly. The researchers then analyzed that data, comparing it to the age of the individual chimpanzees at the time the photos were taken.

The researchers hypothesize there could be several reasons why chimpanzees did not evolve graying hair patterns similar to humans. Their signature dark pigmentation might be critical for thermoregulation or helping individuals identify one another.

Dr. Brenda Bradley, an associate professor of anthropology, is the senior author on the paper. This research dates back to an observation Dr. Bradley made while visiting a field site in Uganda five years ago. As she was learning the names of various wild chimpanzees, she found herself making assumptions about how old they were based on their pigmentation. On-site researchers told her that chimps did not go gray the same way humans do. Dr. Bradley was curious to learn if that observation could be quantified.

There has been little previous research on pigmentation loss in chimpanzees or any wild mammals, Dr. Bradley said. Most existing research on human graying is oriented around the cosmetic industry and clinical dermatology.

"There's a lot of work done on trying to understand physiology and maybe how to override it," Dr. Bradley said. "But very little work done on an evolutionary framework for why is this something that seems to be so prevalent in humans."

The researchers plan to build on their findings by looking at the pattern of gene expression in individual chimpanzee hairs. This will help determine whether changes are taking place at the genetic level that match changes the eye can see.

This study comes ahead of World Chimpanzee Day on July 14. GW's faculty and student researchers make contributions to our global understanding of chimpanzees and primates as part of the GW Center for the Advanced Study of Human Paleobiology. Through various labs, investigators study the evolution of social behavior in the chimpanzees and bonobos, the evolution of primate brain structure, and lead on-the-ground projects at the Gombe Stream Research Center in Tanzania. Dr. Bradley's lab is also currently working on research about color vision and hair variation in lemurs.

UTICA, NY-- Nearly 20% of all COVID-19-associated deaths are from cardiac complications, yet the mechanisms from which these complications arise have remained a topic of debate in the cardiology community. One hypothesis centers on the infection of the heart itself, but the understanding of which cells may be infected is unclear. To address this, MMRI Assistant Professor Dr. Nathan Tucker, in collaboration with the Broad Institute, the University of Pennsylvania, and Bayer US, report the distribution of the SARS-CoV-2 receptor in a manuscript titled, "Myocyte upregulation of ACE2 in cardiovascular disease" published in the journal, Circulation.

COVID-19 (SARS-CoV-2) infects cells through a particular cellular molecule, termed ACE2. To assess levels of this molecule in different patient populations and in response to common hypertension medications (ACE inhibitors), the group applied state-of-the-art single nucleus sequencing technologies in human heart samples. From these studies, they were able to conclude that the amount of the viral receptor is increased in patients with pre-existing cardiac conditions, but only in the beating cells of the heart, termed cardiomyocytes. Additionally, they found that the effect of anti-hypertension medications, termed ACE inhibitors, do not appreciably affect the levels of ACE2 in a way that would support any changes in clinical use of these medications.

"This is but an early step in our understanding of cardiac pathology in people who contract COVID-19," said Tucker, the first author of the manuscript. "There's much more work to do. As an example, we are already working to establish direct evidence of cardiac infection, while also examining receptor distributions in other populations and through other approaches. We hope to provide more information as soon as we are able."

While just a piece in a very complex puzzle, this study offers a potential explanation as to why patients with pre-existing heart disease are more likely to suffer severe cardiac symptoms from COVID-19 infection. Importantly, it also provides data on the effects of anti-hypertensive medications, supporting the previous statements urging continued use of ACE inhibitors from the American Heart Association, American College of Cardiology, and European Society of Cardiology with additional human-derived data.

Volume 11, Issue 28 of Oncotarget features "Lipid and protein tumor markers for head and neck squamous cell carcinoma identified by imaging mass spectrometry" by Schmidt et, al. which reported that the authors used MALDI imaging mass spectrometry and immunohistochemistry to seek tumor-specific expression of proteins and lipids in HNSCC samples.

Among low molecular weight proteins visualized, S100A8 and S100A9 were found to be expressed in the regions of tumor tissue but not in the surrounding healthy stroma of a post-operative microdissected tissue.

Furthermore, the marker potential of lysophospholipids was supported by elevated expression levels of the lysophospholipid degrading enzyme lysophospholipase A1 in the tumor regions of paraffin-embedded HNSCC samples.

Finally, experimental evidence of 3D cell spheroid tests showed that LPC facilitates HNSCC invasion, implying that HNSCC progression in vivo may be dependent on lysophospholipid supply.

Altogether, a series of novel proteins and lipid species were identified by IMS and IHC screening, which may serve as potential molecular markers for tumor diagnosis, prognosis, and may pave the way to better understand HNSCC pathophysiology.

Dr. Zsolt Balogi and Dr. László Márk from The University of Pécs said, "Head and neck squamous cell carcinoma (HNSCC) includes a family of tumors arising from multiple locations (mouth, throat, larynx, sinuses and salivary glands) and is currently the sixth most common cancer worldwide."

Improving treatment success rates would require earlier and more precise diagnosis as well as clinically applicable specific molecular markers of the tumor with prognostic value.

To date, molecular marker candidates of HNSCC include HPV, EGFR mutations, chemokine receptors, methylation markers, interleukins, which are mostly related to a subgroup of cases and also fail to provide a basis for specific and sensitive tumor identification.

Therefore, seeking molecular markers for early and precise diagnosis, reliable prediction of treatment results, and recurrence rate remain a major goal in fighting HNSCC. Receptor mutations or changes in protein expression levels and localization have long been in the focus of tumor marker discovery, and recently lipidomic and metabolomic patterns have been outlining a molecular signature that may be of diagnostic and prognostic value.

Screening for tumor-associated LMW protein and lipid changes in HNSCC tissue, here the authors identify S100A8, S100A9 and specific phospholipids to accumulate and lysophosphatidylcholine to be depleted in the tumor.

The Balogi/Márk Research Team concluded in their Oncotarget Research Paper that elevated expression of S100A8 and S100A9, upregulation of LYPLA1, and concomitant depletion of specific lysophospholipids, paralleled with an accumulation of specific phospholipids were identified as potential tumor markers via imaging mass spectrometry and immunohistochemistry-based screening of HNSCC specimens.

Given that S100A8/9 supports CD36-mediated fatty acid uptake we propose that a set of molecular changes identified in this study may represent a fingerprint of fatty acid and lipid dependence of HNSCC pathophysiology.

"Given that S100A8/9 supports CD36-mediated fatty acid uptake we propose that a set of molecular changes identified in this study may represent a fingerprint of fatty acid and lipid dependence of HNSCC pathophysiology."

Together with serum and blood sample information, this molecular signature of HNSCC tumors might be used as future possible pre- or post-operative diagnostic and prognostic tools.

A research team led by Cardiff University scientists say they are closer to understanding how a supermassive black hole (SMBH) is born thanks to a new technique that has enabled them to zoom in on one of these enigmatic cosmic objects in unprecedented detail.

Scientists are unsure as to whether SMBHs were formed in the extreme conditions shortly after the big bang, in a process dubbed a 'direct collapse', or were grown much later from 'seed' black holes resulting from the death of massive stars.

If the former method were true, SMBHs would be born with extremely large masses - hundreds of thousands to millions of times more massive than our Sun - and would have a fixed minimum size.

If the latter were true then SMBHs would start out relatively small, around 100 times the mass of our Sun, and start to grow larger over time by feeding on the stars and gas clouds that live around them.

Astronomers have long been striving to find the lowest mass SMBHs, which are the missing links needed to decipher this problem.

In a study published today, the Cardiff-led team has pushed the boundaries, revealing one of the lowest-mass SMBHs ever observed at the centre of a nearby galaxy, weighing less than one million times the mass of our sun.

The SMBH lives in a galaxy that is familiarly known as "Mirach's Ghost", due to its close proximity to a very bright star called Mirach, giving it a ghostly shadow.

The findings were made using a new technique with the Atacama Large Millimeter/submillimeter Array (ALMA), a state-of-the-art telescope situated high on the Chajnantor plateau in the Chilean Andes that is used to study light from some of the coldest objects in the Universe.

"The SMBH in Mirach's Ghost appears to have a mass within the range predicted by 'direct collapse' models," said Dr Tim Davis from Cardiff University's School of Physics and Astronomy.

"We know it is currently active and swallowing gas, so some of the more extreme 'direct collapse' models that only make very massive SMBHs cannot be true.

"This on its own is not enough to definitively tell the difference between the 'seed' picture and 'direct collapse' - we need to understand the statistics for that - but this is a massive step in the right direction."

Black holes are objects that have collapsed under the weight of gravity, leaving behind small but incredibly dense regions of space from which nothing can escape, not even light.

An SMBH is the largest type of black hole that can be hundreds of thousands, if not billions, of times the mass of the Sun.

It is believed that nearly all large galaxies, such as our own Milky Way, contain an SMBH located at its centre.

"SMBHs have also been found in very distant galaxies as they appeared just a few hundred million years after the big bang", said Dr Marc Sarzi, a member of Dr. Davis' team from the Armagh Observatory & Planetarium.

"This suggest that at least some SMBHs could have grown very massive in a very short time, which is hard to explain according to models for the formation and evolution of galaxies."

"All black holes grow as they swallow gas clouds and disrupt stars that venture too close to them, but some have more active lives than others."

"Looking for the smallest SMBHs in nearby galaxies could therefore help us reveal how SMBHs start off," continued Dr. Sarzi.

In their study, the international team used brand new techniques to zoom further into the heart of a small nearby galaxy, called NGC404, than ever before, allowing them to observe the swirling gas clouds that surrounded the SMBH at its centre.

The ALMA telescope enabled the team to resolve the gas clouds in the heart of the galaxy, revealing details only 1.5 light years across, making this one of the highest resolution maps of gas ever made of another galaxy.

Being able to observe this galaxy with such high resolution enabled the team to overcome a decade's worth of conflicting results and reveal the true nature of the SMBH at the galaxy's centre.

"Our study demonstrates that with this new technique we can really begin to explore both the properties and origins of these mysterious objects," continued Dr Davis.

"If there is a minimum mass for a supermassive black hole, we haven't found it yet."

By studying fifty COVID-19 patients, researchers in France identified a unique signature - a combination of deficiency in a response of a particular interferon, as well as exacerbated inflammation - in the most critically ill. They propose this signature, which may be a hallmark of severe COVID-19, provides a rationale for therapeutic approaches that combine interferon supplementation with neutralization of inflammatory signaling. COVID-19 is characterized by distinct patterns of disease progression depending on the patient, which implies patients exhibit different immune responses to the SARS-Cov-2 virus. So far, studies suggest some 5-10% of patients progress to severe or critical disease. However, little is known about the immunological features involved in COVID-19 severity. To help to fill this gap, Jérome Hadjadj and colleagues analyzed immune cells of COVID-19 patients with symptoms ranging from mild to critical. The critical patients exhibited a distinctive dual signature involving a deficiency in responses of type I interferons, proteins that help fight viral infections, as well as exacerbated proinflammatory signaling. While recent work to investigate the role of interferon signaling in COVID-19 patients has shown that local interferon signaling may be important to mitigate disease progression, the results of Hadjadj et al. suggest broader production of interferons may in fact be beneficial. The work of these studies collectively reinforces a growing hypothesis that the location, timing, and duration of interferon exposure are critical parameters underlying the success of therapeutics for SARS-CoV-2 infections. Hadjadj et al. also suggest severely ill COVID-19 patients could be treated with a combined approach focused on interferon administration and adapted anti-inflammatory therapies, "a hypothesis worth cautious testing," they say.

LA JOLLA, CA--A team led by scientists at Scripps Research has discovered a common molecular feature found in many of the human antibodies that neutralize SARS-CoV-2, the coronavirus that causes COVID-19.

The scientists, whose study appears July 13 in Science, reviewed data on nearly 300 anti-SARS-CoV-2 antibodies that their labs and others have found in convalescent COVID-19 patients over the past few months. They noted that a subset of these antibodies is particularly powerful at neutralizing the virus--and these potent antibodies are all encoded, in part, by the same antibody gene, IGHV3-53.

The scientists used a powerful tool known as X-ray crystallography to image two of these antibodies attached to their target site on SARS-CoV-2. The resulting atomic-structure details of this interaction should be useful to vaccine designers, as well as to scientists hoping to develop antiviral drugs targeting the same site on SARS-CoV-2.

Prior research suggests that antibodies encoded by IGHV3-53 are generally present, at least in small numbers, in healthy people's blood. The results therefore offer hope that using a vaccine to boost levels of these ever-present antibodies will protect adequately against the virus.

"This type of antibody has been isolated frequently in studies of COVID-19 patients, and we can now understand the structural basis for its interaction with SARS-CoV-2," says the study's senior author Ian Wilson, DPhil, Hansen Professor of Structural Biology and Chair of the Department of Integrative Structural and Computational Biology at Scripps Research.

"This study provides important inspiration for effective COVID-19 vaccine design," says co-author Dennis Burton, PhD, professor and co-chair of the Department of Immunology and Microbiology at Scripps Research.

The research was a collaboration chiefly involving the Wilson and Burton labs, and the Scripps Research-based Neutralizing Antibody Center of IAVI, a prominent non-profit vaccine research organization.

SARS-CoV-2 so far has infected more than 12 million people around the world and killed more than 500,000, in addition to causing widespread socioeconomic disruption and damage. Developing an effective vaccine to stop the pandemic is currently the world's top public health priority.

Although several potential vaccines are already in clinical trials, scientists don't yet have a full understanding of the molecular features that would define a protective antibody response. In the new study, the scientists took a big step toward that goal.

The team started by analyzing 294 different SARS-CoV-2-neutralizing antibodies isolated from COVID-19 patients' blood over the past few months. Antibodies are Y-shaped proteins made in immune cells called B-cells. Each B-cell makes a specific antibody type, or clone, which is encoded by a unique combination of antibody genes in the cell. The scientists found that an antibody gene called IGHV3-53 was the most common of the genes for the 294 antibodies, encoding about 10 percent of them.

The scientists also noted that the IGHV3-53-encoded antibodies in their study contain an unusually short variant of the CDR H3 loop, normally a key target-binding element. These antibodies are nevertheless very potent against SARS-CoV-2 when compared to other antibodies not encoded by IGHV3-53.

A powerful response right off the bat

The IGHV3-53 antibodies had yet another property suggesting that boosting their numbers would be a good and achievable aim for a SARS-CoV-2 vaccine: They appeared to have mutated only minimally from the original versions that would be circulating, initially in small numbers, in the blood of healthy people.

Normally, when activated by an encounter with a virus to which they fit, B-cells will start proliferating and also mutating parts of their antibody genes, in order to generate new B-cells whose antibodies fit the viral target even better. The more mutations needed for this "affinity maturation" process to generate virus-neutralizing antibodies, the harder it can be to induce this same process with a vaccine.

Fortunately, the IGHV3-53 antibodies found in the study seemed to have undergone little or no affinity maturation and yet were already very potent at neutralizing the virus--which hints that a vaccine may be able to induce a protective response from these potent neutralizers relatively easily.

"Coronaviruses have been around for hundreds to thousands of years, and one can imagine that our immune system has evolved in such a way that we carry antibodies like these that can make a powerful response right off the bat, so to speak" Wilson says.

Map for vaccine-makers, gauge for clinical trials

Wilson's team used high-resolution X-ray crystallography to image two different IGHV3-53 antibodies bound to their target on SARS-CoV-2. This target, known as the receptor binding site, is a crucial structure on the viral "spike" protein that normally connects to a receptor on human cells to begin the process of cell infection. Many of the antibodies that neutralize SARS-CoV-2 appear to do so by blocking this virus-receptor connection.

"We were able to reveal unique structural features of these IGHV3-53-encoded antibodies--features that facilitate their high binding affinity and their specificity for the SARS-CoV-2 receptor binding site," says co-first author Meng Yuan, PhD, a postdoctoral research associate in the Wilson lab.

The detailed atomic-scale structural data should be of interest to vaccine designers and drug developers. Moreover, the researchers say, the identification of IGHV3-53-encoded antibodies as key elements of the immune response to COVID-19 suggests that levels of these antibodies might be useful as an indirect marker of success in ongoing and future vaccine trials.

An analysis of nearly 300 recently identified human SARS-CoV-2 antibodies uncovered a gene frequently used in antibodies that most effectively target the virus. The results contribute to growing structural insight that will be needed for successful vaccine development against SARS-CoV-2. As the global COVID-19 pandemic continues, multiple vaccine candidates have entered clinical trials. Yet, the molecular features that contribute to the most effective antibody response remain unclear. The spike protein of SARS-CoV-2 uses its receptor binding domain (RBD) to infect the host receptor, ACE2, on human cells. Antibodies that could target RBD and block binding to ACE2 are highly sought, and a number have been discovered. Here, Yuan Meng and colleagues compiled a list of 294 such RBD-targeting antibodies. By analyzing them, they found that a gene in the IGHV gene family, known as IGHV3-53, is the most frequently used IGHV gene for targeting the RBD of the virus spike protein. IGHV3-53 antibodies, the authors say, not only have lower mutation rates but are also more potent. By studying the crystal structures of two IGHV3-53 antibodies bound to the RBD, the researchers identified the features that lead them to be so effective at binding and so highly potent, features that make them promising for vaccine design. This detailed insight into IGHV-53 neutralizing antibodies should facilitate design of vaccine antigens that elicit this type of neutralizing antibody response, the authors say. "As IGHV3-53 is found at a reasonable frequency in healthy individuals, this particular antibody response could be commonly elicited during vaccination," they write.

Antibodies derived from llamas have been shown to neutralise the SARS-CoV-2 virus in lab tests, UK researchers announced today.

The team involves researchers from the Rosalind Franklin Institute, Oxford University, Diamond Light Source and Public Health England. They hope the antibodies - known as nanobodies due to their small size - could eventually be developed as a treatment for patients with severe COVID-19. The peer reviewed findings are published in Nature Structural & Molecular Biology.

Llamas, camels and alpacas naturally produce quantities of small antibodies with a simpler structure, that can be turned into nanobodies. The team engineered their new nanobodies using a collection of antibodies taken from llama blood cells. They have shown that the nanobodies bind tightly to the spike protein of the SARS-CoV-2 virus, blocking it from entering human cells and stopping infection.

Using advanced imaging with X-rays and electrons at Diamond Light Source and Oxford University, the team also identified that the nanobodies bind to the spike protein in a new and different way to other antibodies already discovered.

There is currently no cure or vaccine for COVID-19. However, transfusion of critically ill patients with serum from convalesced individuals, which contain human antibodies against the virus, has been shown to greatly improve clinical outcome. This process, known as passive immunisation, has been used for over 100 years, but it is not straightforward to identify the right individuals with the right antibodies and to give such a blood product safely. A lab-based product which can be made on demand would have considerable advantages and could be used earlier in the disease where it is likely to be more effective.

Professor James Naismith, Director of The Rosalind Franklin Institute and Professor of Structural Biology at Oxford University said: "These nanobodies have the potential to be used in a similar way to convalescent serum, effectively stopping progression of the virus in patients who are ill. We were able to combine one of the nanobodies with a human antibody and show the combination was even more powerful than either alone. Combinations are particularly useful since the virus has to change multiple things at the same time to escape; this is very hard for the virus to do. The nanobodies also have potential as a powerful diagnostic."

Professor Ray Owens from Oxford University, who leads the nanobody program at the Franklin, said: "This research is a great example of team work in science, as we have created, analysed and tested the nanobodies in 12 weeks. This has seen the team carry out experiments in just a few days, that would typically take months to complete. We are hopeful that we can push this breakthrough on into pre-clinical trials."

Professor David Stuart, from Diamond Light Source and Oxford University said: "The electron microscopy structures showed us that the three nanobodies can bind to the virus spike, essentially covering up the portions that the virus uses to enter human cells."

The team started from a lab-based library of llama antibodies. They are now screening antibodies from Fifi, one of the 'Franklin llamas' based at the University of Reading, taken after she was immunised with harmless purified virus proteins.

The team are investigating preliminary results which show that Fifi's immune system has produced different antibodies from those already identified, which will enable cocktails of nanobodies to be tested against the virus.

The Rosalind Franklin Institute is a new research institute funded through UK Research and Innovation's Engineering and Physical Sciences Research Council. The Franklin is leading the UK's work in the innovative field of nanobodies, whose tiny size and specificity make them perfect tools for scientific research, usually used to stabilise proteins for imaging.
The Institute is named for the researcher Rosalind Franklin, who was born 100 years ago this year. Although famous for her contribution to the discovery of DNA, Franklin's later career turned to imaging virus structures, including polio.

Professor Naismith said: "2020 marks the centenary of Franklin's birth. As an institute named for a pioneer of biological imaging, we are proud to follow in her footsteps and continue her work in viruses, applied here to an unprecedented global pandemic. Franklin's work transformed biology, and our projects aspire to that same transformational effect."

New research confirms the high impact of PSMA PET/CT in the detection and management of recurrent disease in prostate cancer patients. In initial results from a multicenter trial assessing the impact of 18F-DCFPyL prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT), a PET-directed change in management was observed in two-thirds of patients. The research was presented at the Society of Nuclear Medicine and Molecular Imaging's 2020 Virtual Annual Meeting.

Prostate cancer is the second most common cancer in men in the United States. According to the American Cancer Society, an estimated one in nine men will receive a prostate cancer diagnosis in his lifetime, and more than 191,000 men will be diagnosed with prostate cancer this year. Approximately 30 to 40 percent of men experience a biochemical recurrence of prostate cancer in which their prostate-specific antigen (PSA) levels rise after initial treatment.

DCFPyL (PSMA) PET/CT has been shown to be effective in diagnosing patients with prostate cancer. To assess its impact on the management of patients with suspected limited recurrent prostate cancer after primary therapy, researchers conducted a prospective, large-scale multicenter trial. The study included 410 men who had biochemical failure after primary therapy, had either no or limited disease on conventional imaging (CT and bone scintigraphy), and had undergone one of several prostate cancer treatments.

PSMA PET/CT identified disease in more than half of the men in whom CT and bone scan scintigraphy was negative. Additional sites of disease were observed in nearly two-thirds of patients in whom limited metastases were detected prior to PET. PSMA PET-directed management changes were recorded in 66 percent of the patients. The most common changes were conversion from observation or systemic therapy to surgery or radiation, or the addition of nodal-directed therapy to salvage surgery or radiation.

"The identification of extent of recurrence and specific sites of recurrence is crucial in determining the most appropriate mode of therapy for these men," noted Ur Metser, MD, professor of radiology at the University of Toronto in Ontario, Canada. "Findings from this study add to the body of evidence on the utility of PSMA PET in the management of prostate cancer patients."

He continued, "At this time, PSMA PET remains investigational in North American jurisdictions. Evidence generated from this study will help in seeking regulatory approvals to make molecular imaging with 18F-DCFPyL widely available and will pave the way for clinical studies that incorporate PSMA PET as a treatment planning tool to assess ultimate impact on patient outcomes."