Human ancestry has been shaped by mixing and matching alleles

Peer-Reviewed Publication

SMBE JOURNALS (MOLECULAR BIOLOGY AND EVOLUTION AND GENOME BIOLOGY AND EVOLUTION)

 

IMAGE: THE EXTENSIVE ADMIXTURE FOUND IN AFRICAN GENOMES IS SYMBOLIZED BY A MARBLED PAINT EFFECT. view more 

CREDIT: JOSEPH LACHANCE ET AL.

The course of human history has been marked by complex patterns of migration, isolation, and admixture, the latter a term that refers to gene flow between individuals from different populations. Admixture results in a blending of genetic lineages, leading to increased genetic diversity within populations. In addition to admixture among modern human populations, ancient humans reproduced with other hominin groups, such as Neanderthals and Denisovans. This resulted in fragments of DNA from these ancient lineages being passed down to modern humans in a process known as introgression. Two recent studies published in Genome Biology and Evolution examine patterns of admixture in two different regions of the world—Africa and the Americas—revealing how this process has shaped the genomes of modern humans.

Africa is the birthplace of humanity, where our species originated and diversified. Because of this, Africa contains the highest levels of genetic diversity and population structure among humans, with non-African populations largely representing a subset of the genetic variation present on the African continent. Genomes of Africans contain mixtures of multiple ancestries, each of which has experienced different evolutionary histories. In the article “Evolutionary Genetics and Admixture in African Populations,” researchers from two institutes – Georgia Institute of Technology and Mediclinic Precise Southern Africa – reviewed how multiple demographic events have shaped African genomes over time (Pfennig, et al. 2023). According to Joseph Lachance, one of the review’s authors, “What stands out is the sheer complexity of human demographic history, especially in Africa. There are many examples of population divergence followed by secondary contact, the legacy of which is written in our genomes.”

For example, ancient introgression from archaic “ghost” populations of hominins that are no longer extant contributed approximately 4–6% of the ancestry of present-day Khoe-San, Mbuti, and western African populations. More recent demographic events that have occurred over the last 10,000 years have similarly resulted in admixture among modern humans, including gene flow among different click-speaking Khoe-San populations, the spread of pastoralism from eastern to southern Africa, and migrations of Bantu speakers across the continent.

Importantly, biomedical studies often fail to capture this diversity, resulting in implications for the health and disease of those with African ancestry. A better understanding of genetic architecture can help predict disease risk in a population or even inform clinical decision-making for individual patients. Such information is critical for equitable biomedical research, leading the study’s authors to call for more ethically conducted studies of genetic variation in Africa. “A critical point right now is the relative lack of African genetic data,” says Lachance. “Most genomic studies have focused on Eurasian populations, and this limitation can exacerbate existing health inequities.”

One avenue for better understanding the genetic architecture of African genomes is the study of ancient DNA: “Going forward, analysis of ancient DNA is expected to become much more common. Future studies are also likely to focus on fine-scale population structure in Africa. However, logistical and financial obstacles persist. There is a clear need for funding mechanisms that build research capacity in Africa.”

A second article recently published in GBE, titled “The impact of modern admixture on archaic human ancestry in human populations,” focuses on admixture in the Americas (Witt, et al. 2023), which were colonized by modern humans relatively recently. The first people to enter the continent were Indigenous Americans who migrated from Siberia. Subsequent migration of Europeans and Africans due to European colonization and the Transatlantic slave trade resulted in admixed populations that combine ancestries from different continents.

In the study, researchers from Brown University, the Universidad Nacional Autónoma de México, and the University of California-Merced analyzed how the resulting gene flow between modern humans redistributed archaic ancestry in admixed genomes. They used data from the 1000 Genomes Project that were acquired from several admixed populations, including Colombians from Medellin, individuals with Mexican Ancestry from Los Angeles, Peruvians from Lima, and Puerto Ricans from Puerto Rico. These genomes were compared to the high-coverage genomes of Neanderthals and Denisovans, ancient hominins that diverged from modern humans about 500,000 years ago and mated with humans in Eurasia before going extinct about 40,000 years ago.

According to one of the study’s authors, Kelsey Witt from Brown University, these admixed populations are relatively understudied compared to more homogeneous populations. “It is common in studies like this for admixed populations to be excluded because the multiple ancestry sources can make those questions harder to answer. For this work, we wanted to focus on admixed populations to determine what we could learn from them, and whether admixed populations could provide information about all of the ancestry sources that contributed to them.”

The study found that the amount of introgression from Neanderthals and Denisovans was proportional to the amount of Indigenous American or European ancestry in each population. Although European and Indigenous American tracts in these admixed genomes have approximately equal proportions of Neanderthal variants, Denisovan variants are found primarily in Indigenous American tracts. This reflects the shared ancestry between Indigenous Americans and Asian populations, which also have higher levels of Denisovan introgression.

Moreover, by searching for archaic alleles present at high frequency in admixed American populations but low frequency in East Asian populations, the study’s authors identified several genes as candidates for adaptive introgression. These genes were related to multiple pathways including immunity, metabolism, and brain development. Such findings have potential implications for the health of individuals in these admixed populations. “We’ve seen many examples of genetic mismatch in the literature,” says Witt, “where some variants were adaptive at some point in the past, but in the present environment, they have a negative impact on health. In addition, in admixed populations, genetic variants that are unique to separate populations may now interact in unexpected (sometimes negative) ways when they are present in the same individual. Our work suggests that some archaic variants are specific to some ancestry sources and not others."

Like Lachance, Witt knows that additional research is needed to continue to untangle the effects of admixture on modern humans. “In a lot of ways, admixed populations in the Americas are straightforward to study because we have a good idea of the timing and number of gene flow events,” notes Witt. “I’d like to apply this work to other admixed populations, where we may not know when admixture occurred or which populations contributed to it, or in cases where the contributing populations are more closely related. I think that the answers in those cases may not be as clear-cut, but they may contribute to a better understanding of those recent admixture events.”

These studies show admixture has played a significant role in shaping human evolution, both in Africa and in the Americas. Admixture not only reshuffles the genetic variation within and between populations, but also introduces new sources of variation that may have adaptive potential. By comparing the genomes of admixed populations with those of their ancestral groups and with those of archaic humans, these studies reveal how the mixing and matching of alleles has shaped the evolution of our species.

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JOURNAL

Genome Biology and Evolution

DOI

10.1093/gbe/evad066 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

The Impact of Modern Admixture on Archaic Human Ancestry in Human Populations

ARTICLE PUBLICATION DATE

18-May-2023

UAF scientists to hunt for clues about Arctic Ocean glaciation

Grant and Award Announcement

UNIVERSITY OF ALASKA FAIRBANKS

Evidence indicates a thick ice sheet, not annual sea ice and icebergs, covered the Arctic Ocean at some point during the last 140,000 years. Now, University of Alaska Fairbanks scientists will be looking for more geologic proof of the ice sheet’s existence, sources, behavior and extent.

UAF Geophysical Institute scientists will focus on the Beaufort and Chukchi seas region, both offshore and onshore. 

They hope to discover the extent of glaciation and improve understanding of the timing of glacial advances and retreats. Those cycles are thought to have occurred approximately 140,000 to 70,000 years ago, a period known as the mid- to late Pleistocene Epoch.

“The story of the Arctic Ocean is much more complicated than we may have originally thought and involves processes that we haven’t really considered before,” said Louise Farquharson, a research assistant professor at the UAF Geophysical Institute and the lead investigator.

Farquharson is working with UAF geophysics professor Bernard Coakley, who specializes in the history and formation of the Arctic Ocean, and research associate professor Andy Aschwanden, who studies glacier and ice sheet responses to atmospheric and oceanographic changes.

The National Science Foundation is funding the two-year project. 

The researchers will build a geographic information system database of existing marine and terrestrial geologic evidence that could relate to a 1-kilometer thick glacier in the Beaufort-Chukchi region. Researchers will use that database to test the hypothesis that glaciation was extensive in the western Arctic Ocean at several points during the late Pleistocene.

A second component would use that database to model what type of climate would have allowed the initial glaciation and subsequent advances and retreats. That will also give scientists information about the main ice sources that contributed to the buildup.

The scientists hope to obtain additional funding for that research.

Knowledge gained through the two research efforts can improve understanding of how climate change affects today’s high-latitude ice sheets, Farquharson said. 

Earth now has only two ice sheets, both of them high-latitude: Greenland and Antarctica. The two sheets cover 3% of Earth’s surface and 11% of the planet’s land. During glacial periods, ice sheets covered up to 8% of Earth’s surface and 25% of the land.

Offshore evidence to be included in the database includes seafloor and ridge scour marks, ocean core samples, bathymetric surveys and sonar data. Onshore evidence includes large boulders known as erratics and old shoreline ridges caused when ice pressing down on the landscape caused the ocean coast to move inland.

Finding onshore evidence is a “bit more complicated,” Farquharson said.

“That’s because we’re not really sure how far on land this Arctic Ocean glacier came, if at all,” she said. “But what we do see are these huge glacial erratics, big boulders up to the size of a car, deposited across the North Slope. There isn’t really a good mechanism for them being placed there other than through glacial transport and deposition.”

One theory states that ice streams flowing from the Canadian archipelago and feeding an Arctic Ocean glacier carried the boulders, which were left behind as the glacier retreated. An ice stream is an area of an ice sheet or ice cap that flows faster than the surrounding ice.

The new project builds on research of recent decades. 

Some of that research comes from Coakley, who co-authored a 2001 paper offering evidence of glaciation rather than the then-prevailing view that only annual sea ice and icebergs covered the Arctic Ocean. That paper described glacial scouring and shaping of the seafloor and large-scale erosion of submarine ridge crests indicative of glacier movement.

That prior work has added to the Arctic Ocean glaciation hypothesis first presented by British glaciologist John Mercer in 1970. Mercer based his hypothesis on commonalities between the modern-day Arctic Ocean and the former sea of West Antarctica now occupied by an ice sheet.

Mercer’s hypothesis has gained traction in the past decade as more Arctic Ocean data has been able to be collected due to advances in technology and the reduced presence of sea ice. Research in the mid- to late 1990s and early 2000s by others found evidence of glacial ice grounding and erosion.

A 2016 paper by Swedish marine geologist Martin Jakobsson provided new evidence of ice-shelf groundings in the central Arctic Ocean. Jakobsson concluded that new data seems to suggest that ice sheet centers existed on the Chukchi or outer East Siberian shelf or both and that the northern East Siberian Islands contained evidence of glacial impacts.

Farquharson and Coakley also hope to test the hypothesis that Arctic Ocean glaciation occurred even as glaciers at lower latitudes receded. Scientists believe, based on geologic records, that the contrasting trends arose from differences in the moisture available for snow and ice formation.

Farquharson led research that produced that finding in 2018. UAF colleagues Daniel Mann of the Department of Geosciences, Pamela Groves of the Institute of Arctic Biology and Ben Jones of the Institute of Northern Engineering, along with scientists from Utah State University and in Germany, are co-authors on that research.

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CONTACTS:

• Louise Farquharson, University of Alaska Fairbanks Geophysical Institute, 907-474-5623, lmfarquharson@alaska.edu

• Rod Boyce, University of Alaska Fairbanks Geophysical Institute, 907-474-7185, rcboyce@alaska.edu

A recent investigation led by the CSIC successfully maps the shallow seabed of the Mediterranean coast using satellite images

The Institute of Marine Sciences of Andalusia (ICMAN-CSIC) conducted a study in Cala Millor (Mallorca, Spain). This research highlights the potential of the methodology in the presence of Posidonia oceanica

Peer-Reviewed Publication

SPANISH NATIONAL RESEARCH COUNCIL (CSIC)

 

IMAGE: SATELLITE-DERIVED BATHYMETRY (SDB) FROM SENTINEL-2 IMAGES (2020) IN SON SERVERA BAY. THE MAIN STUDY AREA, CALA MILLOR BEACH, IS LOCATED IN THE SOUTHERN PART OF THE IMAGE. view more 

CREDIT: SATELLITE-DERIVED BATHYMETRY (SDB) FROM SENTINEL-2 IMAGES (2020) IN SON SERVERA BAY. THE MAIN STUDY AREA, CALA MILLOR BEACH, IS LOCATED IN THE SOUTHERN PART OF THE IMAGE / SANDRA PAOLA VIAÑA-ICMAN

Satellite-derived bathymetry continues to advance and improve rapidly. A recent scientific study has confirmed the effectiveness of a methodology developed to obtain bathymetric data from satellite images in the Western Mediterranean. The results of this research, published in the prestigious International Journal of Applied Earth Observation and Geoinformation, reaffirm the value of this tool for monitoring coastal areas with varying turbidity levels and diverse seafloor characteristics.

The study was conducted in Cala Millor (Mallorca, Spain), an ecosystem of great significance due to its marine biodiversity but also its potential vulnerability to the effects of global change. The researchers successfully and accurately mapped its coastal seabed using satellite images from the Sentinel-2 twin satellites. This study represents the first attempt to test this methodology in an area with the presence of Posidonia oceanica, an endemic Mediterranean aquatic plant with significant ecological value.

This work has been carried out through a collaboration between researchers from the Institute of Marine Sciences of Andalusia (ICMAN-CSIC), the Coastal Observation System of the Balearic Islands (ICTS-SOCIB), and the National Oceanic and Atmospheric Administration (NOAA) of the United States.

"These tools are a valuable support for coastal management, as they provide up-to-date and continuous information on the morphodynamic changes occurring along the coasts. They are relevant in assisting decision-makers and defining effective adaptation measures against the impacts of global change, ultimately contributing to a more resilient coast," explains Sandra Viaña-Borja, a researcher at the ICMAN-CSIC.

Bathymetry, decisive for Marine Strategies                                       

Satellite-Derived Bathymetry (SDB) is moving a step closer towards consolidating itself as an alternative to traditional bathymetric techniques carried out by aircraft or ships. The main advantage that satellites offer is their open-access data and higher spatial coverage, eliminating the need for physical presence in the area or costly deployments. Nevertheless, despite the substantial advancements achieved in recent years, researchers are confronted with the primary challenge of substantiating the global and operational efficacy and precision of replicating these models in regions characterized by distinct features.

This methodology has already been employed with consistent results in other regions of the planet, such as the East Coast of the United States and the Caribbean. Now, it has been evaluated in a different ecosystem, the Mediterranean, where Cala Millor beach is one of the most monitored by the Comprehensive Beach Monitoring System of the ICTS-SOCIB, which has been operating since 2011. Moreover, due to its significance, the European Commission has recently approved a grant for the LIFE AdaptCalaMillor project, aiming to promote the adaptation of this beach to climate change and enhance the resilience of its infrastructure, ecosystems, and services.

Generating detailed maps of underwater topography is crucial to support a wide range of activities near the coast, such as dredging, environmental management, planning communication cable and pipeline routes, infrastructure maintenance, hydrographic applications, navigation, aquaculture and fisheries, research, tourism, and recreational sports. Moreover, bathymetry is one of the key features for the formulation of Marine Strategies, as outlined by the directives of the European Commission. This instrumental component establishes the overarching regulatory framework that guides and governs diverse sectoral policies and administrative measures pertaining to the marine environment.

"Currently, we are implementing these tools in other regions such as Galicia (NE Atlantic), South Korea, and Alaska, where we have obtained promising results. It is important to highlight that, according to the International Hydrographic Organization, more than half of the shallow seafloors in our oceans remain unmapped or are outdated. Satellite-derived bathymetry is a free and easily accessible technology. Undoubtedly, it is the future of coastal monitoring," emphasizes Isabel Caballero de Frutos, a researcher at ICMAN-CSIC.

Funding

This research was supported by the grant OAPN (Observatory TIAMAT, 2715/2021), IJC2019-039382-I and project RTI2018- 098784-J-I00 both funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”; grant PTA2020-018491-I funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”; and by the European Union-NextGenerationEU Agreement between MITECO, CSIC, AZTI, SOCIB, and the universities of Vigo and Cadiz, to promote research and generate scientific knowledge in the field of marine sustainability. The research was also supported by the National Oceanic and Atmospheric Administration (NOAA). This work represents a contribution to CSIC’s Thematic Interdisciplinary Platforms PTI TELEDETECT and PTI OCEANS+.

 

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JOURNAL

International Journal of Applied Earth Observation and Geoinformation

DOI

10.1016/j.jag.2023.103328 

Oldest architectural plans detail mysterious desert mega structures

Peer-Reviewed Publication

UNIVERSITY OF FREIBURG

 

IMAGE: THE DIMENSIONS OF DESERT DRAGONS ONLY BECOME APPARENT FROM THE AIR: AT JEBEL AZ-ZILLIYAT IN SAUDI ARABIA, THE TRUE-TO-SCALE ENGRAVING DEPICTS NEARBY DESERT DRAGONS. view more 

CREDIT: OLIVER BARGE, CNRS

Although human constructions have modified natural spaces for millennia, few plans or maps predate the period of the literate civilizations of Mesopotamia and Ancient Egypt. Researchers from the French research organisation "Centre national de la recherche scientifique" (CNRS), together with Prof. Dr. Frank Preusser from the University of Freiburg, have now been able to identify engravings in Jordan and Saudi Arabia as the oldest known true-to-scale construction plans in human history. The 8,000 to 9,000-year-old engravings depict so-called desert dragons – kilometre long prehistoric megastructures used to trap animals. "Conclusions can be drawn from the findings about the people of the time. The ability to transfer a large space to a small, two-dimensional plan represents a milestone in intelligent behaviour," explains Preusser. The results, which were published in mid-May in the scientific journal PLOS ONE, should help to understand how desert dragons were conceived and built.

Scale plans of desert dragons discovered in Jordan and Saudi Arabia

Both finds are representations of nearby desert dragons engraved with stone tools. First sighted from aircrafts in the 1920s, desert dragons, up to five kilometres long, consist of stone walls that converge in a complex bounded by pits. As archaeologists have been able to determine in recent years, they were used for large-scale trapping of wild animals. In Jordan, there are eight desert dragons in the area of Jibal al-Khasabiyeh. There, the researchers found a depiction engraved in stone that measures 80 by 32 cm, its age is about 9,000 years. At Jebel az-Zilliyat in Saudi Arabia, two visible pairs of dragons are found three and a half kilometres apart. Here, too, a scaled engraving dating back about 8,000 years was discovered with a total length of 382 cm and a width of 235 cm.

Plans of large structures have so far only been attested by rough representations, in stark contrast to the precision of the engravings of al-Khashabiyeh and az-Zilliyat. The question of their exact use and how they were implemented, especially due to the difficulty of grasping the entire complex from the ground, remains for the time being the secret of the people by whom they were created.

The oldest known scale building plan in human history: the depiction of a nearby desert dragon in Jordan is dated to around 9,000 years ago.

CREDIT

Oliver Barge, CNRS

 

Overview of facts:

• Crassard R., Abu-Azizeh W., Barge O., Brochier J.É., Preusser F., Seba H., Kiouche A.E., Régagnon E., Sánchez Priego J.A., Almalki T., Tarawneh M., 2023. The oldest plans to scale of humanmade mega-structures. PLOS ONE 18(5): e0277927. https://doi.org/10.1371/journal.pone.0277927
• Frank Preusser is Professor for Sedimentology at the Institute for Earth and Environmental Sciences, Faculty of Environment and Natural Resources, at the University of Freiburg. His research emphasis is on the response of terrestrial sedimentary systems to climate change and human impact during the Quaternary. In particular, he is investigating the erosion and depositional history of the Alps and environmental developments on the Arabian Peninsula. A special interest is on geochronology, specifically luminescence dating.
• The South-Eastern Badia Archaeological Project (SEBAP; research at Jibal al-Khashabiyeh) is funded by grants from the French Ministry of Foreign Affairs, Al-Hussein Bin Talal University (project No. 164/2016) and the CNRS National Institute for Humanities and Social Sciences. The GLOBALKITES project (research at Jebel az-Zilliyat) was funded by a French National Research Agency grant ANR-12-JSH3-0004-01 (RC). The Dumat al-Jandal archaeological project (research at Jebel az-Zilliyat) was funded by grants from the Saudi Heritage Commission, the French and Italian Ministries of Foreign Affairs, CNRS UMR-8167 Orient & Méditerranée, the University L’Orientale of Naples (Guillaume Charloux and Romolo Loreto).

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JOURNAL

PLoS ONE

DOI

10.1371/journal.pone.0277927 

Ancient climate change solves mystery of vanished South African lakes

Arid regions of South Africa were once home to lakes, a University of Leicester-led study has confirmed

Peer-Reviewed Publication

UNIVERSITY OF LEICESTER

 

IMAGE: ANDREW CARR COLLECTING SEDIMENT SAMPLES DATING TO THE LAST GLACIAL MAXIMUM FROM THE DRY LAKEBED AT SWARTKOLKVLOER. view more 

CREDIT: BRIAN CHASE

New evidence for the presence of ancient lakes in some of the most arid regions of South Africa suggests that Stone Age humans may have been more widespread across the continent than previously thought.

Research jointly led by the University of Leicester argues that more archaeological work in the interior regions of South Africa – a country renowned for its globally-significant archaeological record – may reveal more about our ancient ancestors and their movements. The researchers’ conclusions have been published in the journal PNAS.

South Africa’s Stone Age archaeological record, particularly for the last 150,000 years has been the subject of a great deal of investigation, not least due to the presence of several remarkable coastal caves and rock shelter records. However, the presence of humans, and the resources available to them in the vast interior regions of the country have thus far remained much more enigmatic.

New research by an international team of researchers from South Africa, the United Kingdom, the United States, and France suggests several large bodies of water were sustained in the now arid South African interior during the last Ice Age, particularly 50,000-40,000 years ago, and again 31,000 years ago. Importantly, the group were able to model how much water was required to fill these palaeo-lakes, allowing the climatic changes necessary to create lakes, and the resulting impacts on the region’s hydrology, flora and fauna, to be reconstructed.

Their findings paint a picture of a diverse and fertile region that would have been capable of supporting hunter-gatherer communities of the time.

Team member Dr Andrew Carr from the University of Leicester School of Geography, Geology and the Environment said: “This is currently the best evidence for when these lakes existed. This region has been something of a gap on the map, climatically and archaeologically. We know humans were present at times during the last ice age, as archaeological materials are scattered across the landscape surface. This new work hints at when and why humans used this landscape.

“These areas look inhospitable today, but were seemingly much less so at times in the past, and this has implications for when and how groups of people used the landscape and potentially how they were connected and exchanged ideas.

“It also tells us something about the sensitivity of ecosystems and environments to global climatic change. You can see how these desert landscapes can respond in quite significant ways to global climate changes, and understand how the human species responded and how adaptable it would have been.”

The scientists studied three lakes from the arid western interior of South Africa to as far east as Kimberley. As well as dating shorelines using radiocarbon and luminescence dating methods, they estimated the lake sizes and capacities. Computer models of regional hydrology showed that the conditions necessary to create the studied lakes would have led to widespread changes in the region’s many (presently ephemeral) rivers and lakes as the water table rose.

Dr Carr added: “The next step is to start to look for sites where we can do more direct dating of the occurrence of stone tools in this region. The work shows that at times the region offered a range of resources, and the archaeological ‘gap on the map’ is much more likely to reflect the lack of sites preserving deep archaeological deposits.

“The region is quite challenging for archaeology as most materials lie in the open on the desert surface with no stratigraphic context - hence it's very difficult to know how long it's been there.”

• This research received funding from the National Geographic Society and the University of the Free State.

Andrew Carr collecting sediment samples from a section of exposed Pleistocene lake sediments at Swartkolkvloer.

Brian Stewart surveying the extensive scatters of stone artefacts observed along the margin of a now-dry lakebed near Swartkolkvloer.

View across a now-dry lakebed near Swartkolkvloer. During the last glacial period this and adjacent basin supported what are believed to have been perennial lakes, some up to 60 feet in depth.

View across a now-dry lakebed near Swartkolkvloer. During the last glacial period this and adjacent basin supported what are believed to have been perennial lakes, some up to 60 feet in depth.

CREDIT

Brian Chase

JOURNAL

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2221082120 

ARTICLE TITLE

Paleolakes and socioecological implications of last glacial "greening" of the South African interior

ARTICLE PUBLICATION DATE

15-May-2023

Investing in safe surgery could cut costs and save lives in LMICs

Peer-Reviewed Publication

UNIVERSITY OF BIRMINGHAM

Investing in developing systems of safe surgery to reduce Surgical Site Infection (SSI) will help to reduce the financial burden on health services in Low- and Middle-Income Countries (LMIC), a new study reveals.

Analysing inpatient resource use in India, Ghana, Nigeria and Mexico, researchers discovered that additional investigations and hospital length of stay for a patient with an SSI compared to patient without an SSI were generally higher in clean-contaminated surgical cases compared to contaminated-dirty surgical cases.

Supported by National Institute for Health and Care Research (NIHR) funding, they found that SSI occurred in 7% of clean-contaminated cases, where wounds have no signs of infection at the time of surgery, whilst 27% of contaminated-dirty cases – where the wound encounters bodily fluids – exhibited SSI.

Overall, SSI was associated with an increase in postoperative healthcare costs by 75.3% (€412) after clean-contaminated surgery and 66.6% (€331) after contaminated-dirty surgery.

Publishing their findings in Journal of Hospital Infection, the international group of researchers, led by the University of Birmingham, reveal that the highest and lowest cost increases were in India for clean-contaminated cases (€517) and contaminated-dirty cases (€223). Overall, inpatient costs accounted for 96.4% of total healthcare costs after clean-contaminated surgery and 92.5% after contaminated-dirty surgery.

Study lead Mr Mark Monahan, from the University of Birmingham’s Institute of Applied Health Research, commented: “Surgical site infection is the world’s most common postoperative complication. This is the first multi-continental surgical cost study of its kind and reveals substantial additional postoperative costs associated with SSI across a range of settings.

“Investing in health technologies to reduce SSI could reduce this major financial burden to patients and low-resource health systems – helping to improve the overall quality of healthcare and ultimately saving lives.”

Researchers found that patients with an SSI had higher costs in both postoperative inpatient costs and post-discharge costs compared to patients without an SSI. They discovered that SSI was a statistically significant variable in determining postoperative healthcare costs.

Postoperative inpatient costs made up most of the total healthcare costs in both clean-contaminated and contaminated-dirty cases. An exploratory investigation in Ghana showed that the costs of unresolved SSI persist beyond 30 days.

The experts note that this is an important finding because 37.5% of prospective patients with an SSI were unresolved at 30 days post-surgery, potentially underestimating the true postoperative costs.

The study was part of the wider FALCON trial led by the NIHR Global Health Research Unit on Global Surgery – an initiative led by the University of Birmingham. Carried out in Benin, Ghana, India, Mexico, Nigeria, Rwanda and South Africa, FALCON evaluated measures to reduce SSI rates in patients undergoing surgery with an abdominal incision.

Patients who develop SSI experience pain, disability, poor healing with risk of wound breakdown, prolonged recovery times and psychological challenges. Those patients in LMICs are disproportionately affected by higher rates of SSI compared to those in high-income countries - increasing the risk of catastrophic expenditure, impoverishment, and wider negative community impact.

ENDS

Notes to Editors

• The University of Birmingham is ranked amongst the world’s top 100 institutions, its work brings people from across the world to Birmingham, including researchers and teachers and more than 8,000 international students from over 150 countries.
• ‘The costs of surgical site infection after abdominal surgery in middle income countries: Key resource use In Wound Infection (KIWI)’ - Mark Monahan, James Glasbey, Tracy Roberts, Sue Jowett, Tom Pinkney, Aneel Bhangu, Dion G. Morton, Antonio Ramos de la Medina, Dhruva N. Ghosh, Adesoji O. Ademuyiwa, Faustin Ntirenganya, Stephen Tabiri, on behalf of the NIHR Global Research Health Unit on Global Surgery is published by Journal of Hospital Infection.
• Participating institutions include University of Birmingham; Global Surgery Research Centre, Hospital Español de Veracruz, México; India Hub NIHR Global Health Research Unit on Global Surgery, Ludhiana, India; Christian Medical College, Ludhiana, India; College of Medicine and Lagos University Teaching Hospital, Lagos, Nigeria; University of Rwanda, Kigali, Rwanda; and University for Development Studies and Tamale Teaching Hospital, Tamale, Ghana.

About the National Institute for Health and Care Research

The mission of the National Institute for Health and Care Research (NIHR) is to improve the health and wealth of the nation through research. We do this by:

•         Funding high quality, timely research that benefits the NHS, public health and social care;

•         Investing in world-class expertise, facilities and a skilled delivery workforce to translate discoveries into improved treatments and services;

•         Partnering with patients, service users, carers and communities, improving the relevance, quality and impact of our research;

•         Attracting, training and supporting the best researchers to tackle complex health and social care challenges;

•         Collaborating with other public funders, charities and industry to help shape a cohesive and globally competitive research system;

•         Funding applied global health research and training to meet the needs of the poorest people in low- and middle-income countries.

NIHR is funded by the Department of Health and Social Care. Its work in low- and middle-income countries is principally funded through UK Aid from the UK government.

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JOURNAL

Journal of Hospital Infection

METHOD OF RESEARCH

Randomized controlled/clinical trial

SUBJECT OF RESEARCH

People

ARTICLE TITLE

• ‘The costs of surgical site infection after abdominal surgery in middle income countries: Key resource use In Wound Infection (KIWI)’

UC San Diego researchers present new wireless system for greater 5G access

Reports and Proceedings

UNIVERSITY OF CALIFORNIA - SAN DIEGO

A new paper on wireless connectivity from the lab of Dinesh Bharadia, an affiliate of the UC San Diego Qualcomm Institute (QI) and faculty member with the Jacobs School of Engineering’s Department of Electrical and Computer Engineering, introduces a new technique for increasing access to the 5G-and-beyond millimeter wave (mmWave) network. 

“Energy grids and mmWave/sub-THz networks share a remarkable similarity; both face fundamental challenges in efficient distribution,” said Bharadia. “Just as energy grids generate substantial amounts of energy but encounter significant hurdles in efficiently delivering it to homes, the utilization of mmWave/sub-THz networks for seamless data connectivity presents a similar predicament. Despite abundantly available bandwidth in these spectra, the efficient distribution of data with these spectra to user devices remains a formidable challenge.”

The paper, “mmFlexible: Flexible Directional Frequency Multiplexing for Multi-user mmWave Networks,” was presented by Ph.D. student and lead author Ish Kumar Jain at the IEEE International Conference on Computer Communications in New York on Wednesday, May 17. 

Sharing Access

With the introduction of more automation and greater speeds and processing power behind wireless networks, the infrastructure that connects people to these resources has fallen behind.

Jain was drawn to the challenge of creating a device that could bridge this gap and give people greater access to the 5G mmWave network. 

5G mmWave systems use radio frequencies to connect everything from “smart” cars to handheld devices and virtual reality sets to wireless networks. The advancement from 4G to 5G allows for higher speeds and bandwidth overall.

Part of the problem, Jain says, is that the jump from 4G to 5G opened up far more resources and processing power than existing infrastructure could handle. mmWave systems depend on a “pencil beam” distribution model in which a base station sends out a single beam of coverage, like shining a light in the dark. Everyone within that beam has access to all resources that the 5G mmWave network has to offer, regardless of whether their devices can process them.

This can lead to a waste of bandwidth that might otherwise have been leveraged by users in other regions. Even shifting this beam, like a lighthouse rotating slowly at timed intervals, creates lag for those who fall beyond its range.

To address the combined issues of wasted bandwidth and lag, Jain, Rohith Reddy Vennam and Raghav Subbaraman, also Ph.D. students in Bharadia’s Wireless Communication, Sensing and Networking Group (WCSNG), set out to determine whether they could create an antenna array that served users in multiple directions without sacrificing distance and power. 

The team designed a prototype device that works in concert with a novel array of antennas to divide a single frequency band into multiple usable beams. Called a delay phased array, this antenna arrangement leverages 5G mmWave’s sheer amount of bandwidth to connect multiple regions to the network and can be tailored to deliver greater connection to those who need it.

This new, programmable array can also be built using existing technologies and scaled up with a very high number of antennas to support all future devices. 

Through experiments run in QI’s Atkinson Hall on the UC San Diego campus, the team found mmFlexible decreased lag by 60-150%.

“It’s very exciting to see new generations of applications coming up,” said Jain. “But I feel, in the future, the number of [wireless] devices will grow and so will their demand for wireless spectrum. These are the key things that motivate me to further explore these innovative techniques.”

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ARTICLE TITLE

mmFlexible: Flexible Directional Frequency Multiplexing for Multi-user mmWave Networks

Tonsillectomy both clinically and cost effective for adults

Peer-Reviewed Publication

NEWCASTLE UNIVERSITY

 

IMAGE: DR JAMES O’HARA, CLINICAL SENIOR LECTURER AT NEWCASTLE UNIVERSITY AND CONSULTANT EAR, NOSE AND THROAT SURGEON AT NEWCASTLE UPON TYNE HOSPITALS NHS FOUNDATION TRUST. view more 

CREDIT: STEVEN BARBER/DR JAMES O’HARA

Scientists say tonsil removal is both clinically and cost effective for adults who get recurrent severe sore throats.

The biggest study of its kind, carried out by Newcastle University, revealed that patients who had a tonsillectomy had 50% less sore throats over two years, compared to patients who did not undergo tonsillectomy. Publishing today (17 May) in The Lancet, the study was funded by the National Institute for Health and Care Research (NIHR).

Experts also found that a tonsillectomy for those aged 16 years and over was cost effective in comparison to treatment with painkillers and ad hoc antibiotics.

Tonsillectomy assurance

A tonsillectomy, cutting out the two lumps of lymphoid tissue found at either side of the back of the throat, is an operation that has been widely used to improve the quality of life for patients.  

However, in recent years, less adult tonsillectomies have been reportedly carried out on NHS patients.

Dr James O’Hara, Clinical Senior Lecturer at Newcastle University and Consultant Ear, Nose and Throat surgeon at Newcastle Upon Tyne Hospitals NHS Foundation Trust, said: “Tonsillectomy has been branded as an ‘intervention of limited clinical value’ due to a lack of studies to support the operation.

“Over the last 20 years, the number of tonsillectomies being performed in the UK has halved whilst hospital admissions for complicated tonsillitis have more than doubled.

“There has been variation across the UK in referrals from primary care for tonsillitis, with some patients having to experience three times the recommended number of episodes before being referred for a tonsillectomy.

“Our research should level the threshold for referral for this problem, and clinicians can now be assured that tonsillectomy is effective for those who suffer with recurrent tonsillitis.”

In the study, commissioned by the NIHR, almost 500 patients were randomised to either early tonsillectomy or given treatment such as painkillers and antibiotics.

Participants were only recruited if they met the current national guidance for offering tonsillectomy - seven episodes of tonsillitis in a year, five per year for two years, or three episodes for three years.

Those in the clinical trial who underwent the operation suffered half the number of days with sore throats over the following two years, including the two weeks of sore throats following the procedure.

Cost effective procedure

The Newcastle-led research also showed that it is more cost effective for the NHS to offer tonsillectomy to eligible patients than to treat them by other conventional methods.

Dr O’Hara said: “Whilst we now know that tonsillectomy is effective, patients still need to weigh up the potential benefits in reducing longer-term sore throats with 14 days of pain following the operation.

“There is also a risk of one in five patients bleeding following the operation, with some having to return to hospital. Further research is needed to improve the tonsillectomy operation to make it less painful and reduce the risk of bleeding.”

Professor Andrew Farmer, Director of NIHR’s Health Technology Assessment Programme, said: “These new results provide important findings suggesting that tonsillectomy benefits this group of patients compared to repeated courses of antibiotics and painkillers.

“Once again, high quality independently funded research is providing evidence which could improve health and social care practice and treatments."

Newcastle University and Newcastle Hospitals are both part of Newcastle Health Innovation Partners (NHIP). NHIP is one of eight prestigious Academic Health Science Centres (AHSCs) across the UK, bringing together partners to deliver excellence in research, health education and patient care.

 

Reference:

Conservative management versus tonsillectomy in adults with recurrent acute tonsillitis in the UK (NATTINA): a multicentre, open-label, randomised controlled trial. Janet Wilson et al. The Lancet. 

 

Patient case study

Secondary school teacher, Elinor Barwick, was the first patient recruited to the Newcastle-led trial as her recurrent acute tonsillitis was impacting her life.

Elinor had suffered terrible sore throats for many years, however, things got significantly worse when she became a teacher as she needed to speak all the time, leaving her in a lot of pain and discomfort.

Elinor’s tonsillitis often meant it was hard to swallow both liquids and food. In addition, her tonsillitis would leave her unable to speak as her throat would become extremely tight and swollen, and she would develop flu-like symptoms – all of which would impact her job and quality of life.

Elinor, of Gosforth, Newcastle, was recruited to trial and was one of the participants given the tonsillectomy procedure.

The mother-of-one said: “Recurrent tonsillitis would impact my life as it would leave me in a lot of pain and, at times, made day-to-day life very difficult.

“When I was asked to be part of the trial I didn’t hesitate to say ‘yes’ because it was being led by Newcastle University and would benefit patients like myself.

“Since I have had my tonsils removed, I’ve not had a day off work due to tonsillitis and my quality of life has very much improved as I no longer suffer from severe sore throats.

“It is great that research into the importance of tonsillectomies in adults with recurrent acute tonsillitis has taken place in Newcastle to help patients like myself in the future.”

 

Ends

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JOURNAL

The Lancet

METHOD OF RESEARCH

Randomized controlled/clinical trial

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Conservative management versus tonsillectomy in adults with recurrent acute tonsillitis in the UK (NATTINA): a multicentre, open-label, randomised controlled trial.

ARTICLE PUBLICATION DATE

17-May-2023

Examining mental health, education, employment, and pain in sickle cell disease

JAMA Network Open

Peer-Reviewed Publication

JAMA NETWORK

About The Study: The findings of this cross-sectional analysis of 2,200 individuals with sickle cell disease (SCD) suggest that employment status, sex, age, and depression are associated with pain frequency. Depression screening for these patients is warranted, especially among those experiencing higher pain frequency and severity. Comprehensive treatment and pain reduction must consider the full experiences of patients with SCD, including impacts on mental health. 

Authors: Kelly M. Harris, Ph.D., C.C.C.-S.L.P., of the Washington University in St. Louis School of Medicine, is the corresponding author. 

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

(doi:10.1001/jamanetworkopen.2023.14070)

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

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About JAMA Network Open: JAMA Network Open is an online-only open access general medical journal from the JAMA Network. On weekdays, the journal publishes peer-reviewed clinical research and commentary in more than 40 medical and health subject areas. Every article is free online from the day of publication.

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JOURNAL

JAMA Network Open