Cannabis has same effect on adolescents and adults, and CBD doesn’t dampen effects

Peer-Reviewed Publication

UNIVERSITY COLLEGE LONDON

The short-term effects of vaporised cannabis do not differ between adolescents and adults, while cannabidiol (CBD) does not dampen the effects of the drug, finds a new study led by UCL and King’s College London researchers.

For the experimental study published in Addiction, the researchers measured how regular cannabis users of different ages responded to inhaling cannabis with differing levels of CBD.

The study participants included 24 adolescents (16-17 years old) and 24 adults (26-29 years old), all of whom were already regular users of cannabis (0.5 to three days per week, averaging 1.5 days of cannabis use per week).

In a clinical research facility (Invicro), the participants inhaled three types of vaporised cannabis under close medical supervision. On three separate weeks, participants were given either a placebo, or a strain of cannabis high in delta-9-tetrahydocannabinol (THC, the main psychoactive component, which typically predominates in both illegal and legal markets), or a high-CBD and high-THC version (consisting of the same level of THC, and also containing CBD)*. There were administered in doses comparable to typical recreational use.

The participants were asked to report how the drug was affecting them at regular intervals, and completed tests assessing their verbal memory and the psychotic-like effects of the drug (such as delusions, cognitive disorganisation or paranoia).

The researchers found all the expected effects of cannabis in the THC and THC+CBD conditions, among the participants’ responses: feeling high, feeling anxious, having mild transient psychotic-like experiences, and memory impairment.

However, crucially there was no evidence that adolescents differed from adults in their responses to cannabis, while under the influence.

Lead author, psychology lecturer Dr Will Lawn, who conducted the study at UCL before moving to King’s College London, said: “Immediately following consumption, cannabis can elicit psychotic-like effects, and impair verbal memory, and adolescents in our study who regularly smoke cannabis were just as vulnerable to this as the adults were. Adolescence is a key developmental stage of life, when people are at an increased risk of developing mental health problems.

“Regularly producing transient psychotic-like effects and memory impairments through cannabis use is likely to augment the risk of psychological distress, especially in those who are vulnerable to these harms. However, critically, our results also indicate that 16- to 17-year-old cannabis users were not more sensitive to the acute harmful effects of cannabis than adults.”

In recent years, there has been growing concern about the impact of cannabis on young people, as well as hope that CBD may protect against some cannabis harms. A recent long-term, observational study by the same authors found that adolescents are more vulnerable to cannabis addiction, compared to adult users, but they are not more vulnerable to depression and anxiety.**

Cannabis has natural variation in CBD, which is a non-intoxicating constituent of the drug, as well as the relative levels of THC, which is psychoactive and gets people high.

CBD has rapidly grown as an over-the-counter wellness supplement in recent years, and previously CBD in cannabis had been thought to mitigate against some of the unpleasant effects of THC.

For the latest study, in testing the impact of differing CBD levels, the researchers found that CBD levels did not impact the subjective feel of the drug, and it also did not affect memory impairment or psychotic-like effects.

The researchers say their study does not address high-dose CBD’s potential medical benefits when administered by itself, but the findings do cast doubt on popular suggestions that these lower doses of CBD found in cannabis may protect against THC’s acute effects on memory and psychotic-like experiences.

Dr Lawn said: “Adding a moderate dose of vaporised CBD, about 25mg, to cannabis that is already high in THC does not alter the subjective experience, nor does it protect from effects such as paranoia or memory impairment. However, we have not investigated the long-term effects of low-dose CBD nor the therapeutic effects of high-dose pharmaceutical CBD here.”

Senior author Professor Val Curran (UCL Clinical Psychopharmacology Unit, UCL Psychology & Language Sciences) commented: “Cannabis is the world’s most commonly used internationally controlled drug. It is particularly popular among adolescents, with over 15% of 15-year-olds in England and 28% of those in the US reporting usage in the last year. As cannabis laws are rapidly changing around the globe, it is vital that we understand whether the adolescent brain is more vulnerable, in order to inform regulations and accurate, evidence-based harm reduction messaging. Here, we have found that adolescents are neither more resilient nor more vulnerable to the immediate effects of cannabis.”

The research formed part of the Medical Research Council-funded CannTeen study***, involved researchers at UCL, King’s College London, the University of Bath and Invicro llc, and received full ethical approval from the UCL Ethics Committee. As all participants were over 16 years old, everyone consented as a legal adult. All participants were already cannabis users and the study was completed safely without issues, with medical professionals present at all times.

The researchers say that strengths of this randomised, double-blind, placebo-controlled experiment are the tight experimental controls and that participants in the adult and adolescent groups were carefully matched on their natural cannabis use. The researchers caution that their study does not shed light on long-term impacts of cannabis.

 

* For a 75kg person, the “THC” condition had 8mg of THC, and the “THC+CBD” condition had 8mg of THC + 24mg of CBD. This dose of THC reflects approximately one quarter of a joint, and a moderate dose of CBD that was thought might influence the drug’s effects. The placebo consisted of a product using cannabis as the starting material, but with all cannabinoids (including THC and CBD) removed.

** UCL News, 2022: Adolescents more vulnerable to cannabis addiction but not other mental health risks

*** More about the CannTeen study

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JOURNAL

Addiction

DOI

10.1111/ADD.16154 

METHOD OF RESEARCH

Randomized controlled/clinical trial

SUBJECT OF RESEARCH

People

ARTICLE TITLE

The acute effects of cannabis with and without cannabidiol in adults and adolescents: a randomised, double-blind, placebo-controlled, crossover experiment

ARTICLE PUBLICATION DATE

7-Feb-2023

 Scientists develop new index based on functional morphology to understand how ancestors of modern birds used their wings

Peer-Reviewed Publication

NAGOYA UNIVERSITY

 

IMAGE: SCIENTISTS DEVELOP NEW INDEX TO UNDERSTAND HOW ANCESTORS OF MODERN BIRDS USED THEIR WINGS BASED ON THE STRENGTH OF THE CORACOID BONE (SHOWN IN RED) AND THE ANIMAL’S BODY MASS view more 

CREDIT: REIKO MATSUSHITA

Scientists at Nagoya University in Japan have developed an index to estimate how a bird uses its wings for flight or other locomotion by measuring the strength of the coracoid bone and the animal’s body mass. It should improve our understanding of how extinct animals used their wings and the different patterns of wing-propelled locomotion that emerged as birds evolved. Their findings were published in the Journal of Anatomy.

The presence of a wing alone does not tell us whether an animal can fly. For example, penguins evolved wings to propel them through water whereas feathered dinosaurs may have used their wings for other purposes, such as thermoregulation and intraspecific display. Therefore, to better understand how animals evolved the ability to fly, an index must take into account both the presence of wings and the ability to perform powerful wing-beats.

“We wanted to create a new index because people think that if an animal has wings, then it can fly”, said the study’s second author, Assistant Professor Shin-ichi Fujiwara. “But this is not always true. An animal can also use its wings for other purposes, such as thermal insulation in flightless animals. Our research team focused on how changes in skeletal morphology can lead to changes in locomotion. Subsequently, these changes can lead to major ecological transitions such as a shift in lifestyle from a terrestrial environment to an aerial, aquatic, arboreal, or subterranean environment. The origin of flight in birds has been an important topic in this field. We, therefore, needed to develop an alternative index, based on biomechanics, to determine the flapping ability of birds and which we could also use to measure skeletal remains.”

To create this index, the researchers used the avian coracoid bone. The coracoid bone acts as a strut to prevent the thoracic skeleton from deforming when an animal’s powerful flight muscles, which connect the wings to the sternum, contract. Doctoral student Takumi Akeda of the Department of Earth and Planetary Sciences, Graduate School of Environmental Studies, at Nagoya University, and Fujiwara of the Nagoya University Museum, measured the size of a cross section of the coracoid bone in relation to the body mass of 220 bird specimens. Their sample of 209 species included extinct birds such as the dodo and the great auk.

The researchers then divided the birds into four groups based on how they used their wings. These groups were those that used flapping flight (e.g., pigeons); those that used wing-propelled diving (e.g., penguins); those that were flightless with no flapping ability (e.g., ostriches); and those that used thermal and dynamic soaring (e.g., albatrosses and vultures). Based on the strength of the coracoid bone and flapping ability, the researchers could create a new index to analyze flight patterns.

They found that the strength of the coracoid in relation to body mass may reflect the force exerted by the flight muscles, which counteract the lifting force on the wings. This helps to estimate how a bird uses propulsion. Soaring birds had increased coracoid strength, probably to enable them to withstand the greater bending forces caused by the contraction of the flapping muscles. In contrast, non-flapping birds had lower coracoid strength. These findings show that coracoid strength in relation to body mass reflects the lifting force on the wings, therefore, it is a useful tool for reconstructing the type of propulsion used by the animal.

Akeda and Fujiwara’s index should allow future researchers to assess the flight styles and flapping abilities of not only extinct birds but also other flying animals, including the Pteranodon and Quetzalcoatlus of “Jurassic World” fame. The index could also allow them to estimate the origin of flight in winged theropods, the ancestors of birds.

“The use of coracoid strength is a powerful theoretical framework for reconstructing the origins of pre-flight flapping ability and powered flight,” said Fujiwara. “It seems appropriate to first apply our new index to the extinct taxa in the theropod bird lineage, which includes feathered dinosaurs such as Archaeopteryx and Confuciusornis. We also believe that coracoid bones of Pteranodon and Quetzalcoatlus functioned as struts against the contraction of the flapping muscles. Therefore, our index can potentially reconstruct their flight ability and help answer controversial questions such as whether Quetzalcoatlus could flap its wings to fly.”

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JOURNAL

Journal of Anatomy

DOI

10.1111/joa.13788 

ARTICLE TITLE

Coracoid strength as an indicator of wing-beat propulsion in birds

Can I come, too? How tourism can include people whose health conditions usually keep them at home

Around 20 per cent of the world’s population suffer from chronic diseases such as diabetes, heart disease, cancer, or mental disorders — a group of people the travel industry needs to accommodate

Peer-Reviewed Publication

EDITH COWAN UNIVERSITY

Following the disruption of COVID-19, the global tourism industry has largely opened up again; however, travelling remains a serious challenge for a large group of people.

 

The World Health Organization estimates 20 per cent of the world’s population suffer from non-communicable chronic diseases such as diabetes, heart disease, cancer, or mental disorders.

 

These conditions can make travelling difficult, while some people may even avoid taking holidays altogether.  

 

A cross-disciplinary research project from Edith Cowan University has highlighted the impacts this decision can have on people with these health challenges, and outlined the future repercussions for the industry as a whole.

 

Through collaboration between ECU’s School of Business and Law and its Centre for Precision Health, the project has put forth the concept of ‘travel therapy’, which sees tourism as a means of improving mental health and wellbeing.

 

Researcher Dr Jun Wen said it is vital the tourism industry catered more to vulnerable people with physical or psychological disorders, a market he described as important but too often overlooked.

 

“Most are able to travel but remain vulnerable during trips and need intensive services,” he said.

 

“The world has an ageing population, so there will be more and more people dealing with the challenges that brings, like dementia, physical limitations and so on.

 

“There are also more people being diagnosed with mental health issues, such as depression and anxiety.

 

“Tourism needs to be able to accommodate vulnerable travellers such as these for the industry’s survival — but also because health is important and as our previous work has shown, tourism can help support health.”

 

What the industry can do

 

Dr Wen said there are numerous initiatives which could make destinations more accessible for vulnerable people.

 

Strategies could be implemented throughout the tourism industry chain (food, accommodation, transportation, travel, shopping, and entertainment) and could include considerations or allowances for caregivers who may need to accompany travellers.

 

Dr Wen said education was critical.

 

“Staff and stakeholders need training to be made aware of vulnerable travellers’ needs and demands,” he said.

 

“This can include developing manuals to standardise services for vulnerable travellers, enhancing accessible infrastructure and equipping professional emergency and care facilities appropriately, such as with first-aid tools.

 

“The industry can also customise services for different traveller segments, such as people with dementia, depression or anxiety.”

 

Dr Wen said technological advances could also play a great role in bringing the benefits of tourism to more people.

 

“Not everyone can take physical trips,” he said.

“The tourism industry should develop virtual products that enable all travellers to be present in a destination and to enjoy fun and health-related benefits.”

 

‘Travel medicine in hospitality: An interdisciplinary perspective’ was published in the International Journal of Contemporary Hospitality Management.

 

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JOURNAL

International Journal of Contemporary Hospitality Management

DOI

10.1108/IJCHM-05-2022-0574 

METHOD OF RESEARCH

Commentary/editorial

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Travel medicine in hospitality: an interdisciplinary perspective

Hand hygiene is focus of updated advice to prevent healthcare-associated infections

Only 7% of healthcare personnel fully clean their hands

Reports and Proceedings

SOCIETY FOR HEALTHCARE EPIDEMIOLOGY OF AMERICA

Five medical organizations are recommending updated best practices for hand hygiene to protect patients and staff in healthcare settings. The recommendations emphasize the importance of healthy skin and nails and easy access to alcohol-based hand sanitizers.

Strategies to Prevent Healthcare-Associated Infections through Hand Hygiene: 2022 Update, one in a series of expert guidance documents known collectively as the Compendium, was published today in the journal Infection Control & Hospital Epidemiology.

“Hand hygiene is a basic function of healthcare safety,” said lead author Janet Glowicz, PhD, RN, CIC, with the Centers for Disease Control and Prevention. “By engaging healthcare personnel and establishing reliable processes described in the Compendium, we can achieve effective, consistent hand hygiene. Commitment by healthcare leadership is also necessary to establishing a culture of safety.”

The document addresses how facilities can train healthcare personnel in proper technique, monitor their compliance, engage them in the selection of products to keep their skin healthy, and properly use gloves. It also discusses where facilities should place and how they should maintain alcohol-based sanitizer dispensers and sinks.

The guidance reviews the evidence around nail polish, gel, and shellac, which shows that short, natural nails with standard polish or no polish are easiest to clean. The authors found no new evidence specific to chipped nail polish and artificial nails but note previous findings that they can harbor germs. The guidance leaves specific policies about nail polish, gels, shellac, and artificial nail extenders to the discretion of infection prevention programs at each facility, with the exception of policies for those who scrub for surgery or work in high-risk areas. These personnel should maintain short, natural fingernails free of polish and nail extenders.

Citing research that shows only 7% of healthcare personnel effectively clean the entire surface of their hands, the guidance recommends ongoing training in handwashing and proper use of sanitizer. Thumbs and fingertips were most frequently missed.

The authors recommend that healthcare personnel not be provided with individual, pocket-sized hand sanitizers in lieu of wall-mounted sanitizer dispensers and emphasize that hand sanitizer dispensers always be widely available and never prohibited, even in situations when washing with soap and water are indicated. When healthcare personnel suspect organisms that are difficult to remove, such as C. difficile and noroviruses, healthcare personnel should wear gloves and follow structured techniques for hand washing and hand sanitizing.  In addition, facilities should not top-off sanitizer dispensers meant for single use or provide antimicrobial soaps that contain Triclosan. Facilities also should discourage the use of double gloves, except in certain circumstances.

To encourage compliance and to support healthy skin and nails, facilities should include healthcare personnel in the selection of hand sanitizers and moisturizers, while ensuring the products are compatible with antiseptics and gloves used on site. Maintaining healthy skin is a crucial element of hand hygiene.

Surgical settings require special care, but waterless hand hygiene with surgical hand rubs is acceptable, especially as it improves compliance. Brushes should be avoided in surgery prep due to their negative impact on skin health.

This document updates the 2014 Strategies to Prevent Healthcare-Associated Infections through Hand Hygiene. The Compendium, first published in 2008, is sponsored by the Society for Healthcare Epidemiology (SHEA). It is the product of a collaborative effort led by SHEA, with the Infectious Diseases Society of America, the Association for Professionals in Infection Control and Epidemiology, the American Hospital Association, and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise. The Compendium is a multiyear, highly collaborative guidance-writing effort by over 100 experts from around the world.

Upcoming Compendium updates will include strategies to prevent catheter-associated urinary tract infections, Clostridium difficile infections, methicillin-resistant Staphylococcus aureus infections, and surgical site infections. Strategies for preventing central line-associated bloodstream infections and pneumonia were updated earlier in 2022. Each Compendium article contains infection prevention strategies, performance measures, and example implementation approaches. Compendium recommendations are derived from a synthesis of systematic literature review and evaluation of the evidence, practical and implementation-based considerations, and expert consensus.

###

About ICHE
Published through a partnership between the Society for Healthcare Epidemiology of America and Cambridge University Press, Infection Control & Hospital Epidemiology provides original, peer-reviewed scientific articles for anyone involved with an infection control or epidemiology program in a hospital or healthcare facility. ICHE is ranked 24th out of 94 Infectious Disease Journals in the latest Web of Knowledge Journal Citation Reports from Thomson Reuters.

The Society for Healthcare Epidemiology of America (SHEA) is a professional society representing more than 2,000 physicians and other healthcare professionals around the world who possess expertise and passion for healthcare epidemiology, infection prevention, and antimicrobial stewardship. The society’s work improves public health by establishing infection-prevention measures and supporting antibiotic stewardship among healthcare providers, hospitals, and health systems. This is accomplished by leading research studies, translating research into clinical practice, developing evidence-based policies, optimizing antibiotic stewardship, and advancing the field of healthcare epidemiology. SHEA and its members strive to improve patient outcomes and create a safer, healthier future for all. Visit SHEA online at shea-online.org, facebook.com/SHEApreventingHAIs and twitter.com/SHEA_Epi.

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JOURNAL

Infection Control and Hospital Epidemiology

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Strategies to Prevent Healthcare-Associated Infections through Hand Hygiene: 2022 Update

ARTICLE PUBLICATION DATE

8-Feb-2023

The geometry of conflict

Peer-Reviewed Publication

UNIVERSITY OF ST. ANDREWS

The divergent goals of two opponents—whether they are individual people or entire nations—can be thought of as two points in a multi-dimensional space of possibilities, and the ensuing battle of wills can be described in terms of a ball bouncing around in this same space. When one party gains temporary control of the ball, they move it closer to where they want to to be, but their opponent is then liable to seize control and move the ball in the opposite direction.
The focus of this paper is on conflicts that are of interest to evolutionary biologists—including those occurring between genes, between individuals, between the sexes, and between the generations. The geometric approach reveals that not only are these conflicts liable to continue indefinitely through evolutionary time, but that they are also able to spill out from the initial battleground and cause extensive collateral damage in areas where there is no actual disagreement. The damage is particularly devastating to complex organisms and social structures, and so conflict places an important barrier to the evolution of complexity.
The geometric analysis finds that such collateral damage is greatly reduced if organisms and their societies embody the principle of modular design, which constrains the bouncing ball to move only in certain directions at any given time. This suggests that modularity is a crucial—and previously unappreciated—enabler of complex adaptation and transformative changes in social organisation, from the evolution of multicellular life to the emergence of superorganismal insect societies.

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JOURNAL

Proceedings of the Royal Society B Biological Sciences

DOI

10.1098/rspb.2022.2423 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Cells

ARTICLE TITLE

The Geometry of Evolutionary Conflict

ARTICLE PUBLICATION DATE

8-Feb-2023

Healthcare based on evidence improves patient outcomes and return on investment for hospitals

Peer-Reviewed Publication

WILEY

A recent study examined patients’ outcomes after receiving care based on scientific and clinical evidence. The work, which is published in Worldviews on Evidence-Based Nursing, also reviewed the extent and type of evidence-based practices (EBPs) performed across clinical settings. 

A total of 636 published articles addressing EBP and patient outcomes met investigators’ inclusion criteria. There were many differences in approaches, designs, and outcomes measured among the articles included in the review. 

Most articles (63.3%) were published in the United States, and 90% took place in the acute care setting. Various EBPs were implemented, with just over a third including some aspect of infection prevention, and most (91.2%) linked to reimbursement. The two most reported outcomes were length of stay (15%), followed by mortality (12%). 

“Although our study revealed that EBP improves patient outcomes and reduces costs for healthcare systems, there is much opportunity to improve healthcare quality and safety with EBP as healthcare executives still do not invest enough in their budgets to ensure that all clinicians take this approach to care and that all care is evidence-based, not steeped in tradition, or outdated policies or procedures,” said corresponding author Linda Connor, PhD, RN, CPN, of The Ohio State University. 

URL upon publication: https://onlinelibrary.wiley.com/doi/10.1111/wvn.12621

Additional Information
NOTE: The information contained in this release is protected by copyright. Please include journal attribution in all coverage. For more information or to obtain a PDF of any study, please contact: Sara Henning-Stout, newsroom@wiley.com.

About the Journal
Worldviews on Evidence-Based Nursing is a peer-reviewed journal and top information resource from The Honor Society of Nursing, Sigma Theta Tau International, that uniquely bridges knowledge and application, taking a global approach in its presentation of research, policy and practice, education and management, and its link to action in real world settings.  

About Wiley
Wiley is one of the world’s largest publishers and a global leader in scientific research and career-connected education. Founded in 1807, Wiley enables discovery, powers education, and shapes workforces. Through its industry-leading content, digital platforms, and knowledge networks, the company delivers on its timeless mission to unlock human potential. Visit us at Wiley.com. Follow us on Facebook, Twitter, LinkedIn and Instagram.

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JOURNAL

Worldviews on Evidence-Based Nursing

DOI

10.1111/wvn.12621 

ARTICLE TITLE

Evidence-based Practice Improves Patient Outcomes and Healthcare System Return on Investment: Findings from a Scoping Review

ARTICLE PUBLICATION DATE

8-Feb-2023

Biosensors change the way water contamination is detected

Social scientist and synthetic biologist collaborate to tackle a global challenge

Peer-Reviewed Publication

NORTHWESTERN UNIVERSITY

 

IMAGE: A FAMILY IN RURAL KENYA FIELD TEST THE POINT-OF-USE FLUORIDE BIOSENSORS. view more 

CREDIT: CREDIT: JANET BARSOLAI

EVANSTON, Ill. --- Scientists from Northwestern University have collaborated on the implementation of an accurate, low-cost and easy-to-use test for detecting toxic levels of fluoride in water.

The new biosensor device developed at Northwestern has been field tested in rural Kenya, providing evidence that water testing for fluoride can be easily used outside of a lab and accurately interpreted by nonexperts.

Worldwide, it is estimated that tens of millions of people live in areas where the water supply is contaminated with toxic levels of naturally occurring fluoride, a colorless, odorless and tasteless substance. The scale of the issue has been difficult to measure because of the high cost or complexity of available testing options.

A major step toward addressing global health concerns over access to safe drinking water, the new proven testing method is the result of a rare collaboration between researchers in the fields of anthropology and synthetic biology.

Study findings will be published by NPJ Clean Water on Feb. 8, 2023, at 10 a.m. GMT/4 a.m. CST. After publishing the paper can be accessed here.

The study was co-led by Northwestern anthropologist Sera Young and synthetic biologist Julius Lucks. Young is an associate professor of anthropology and global health studies at Weinberg College of Arts and Sciences and a faculty fellow at the Institute for Policy Research (IPR). Lucks is professor and associate chair of chemical and biological engineering at McCormick School of Engineering. Lucks is also co-director of the Northwestern Center for Synthetic Biology, where Young is also a faculty member.

Young and Lucks say it is the first time they have collected field data together, and it shows what’s possible when social scientists and synthetic biologists put their heads together to address global challenges.

The project builds upon and finds a unique intersection for prior research conducted by both Lucks and Young, who are married.

In 2017, Young and colleagues developed the Water Insecurity Experiences Scales to provide a measurement of global water insecurity that takes human experiences into account. Young partnered with the Gallup World Poll to publish estimates for half of the globe using the WISE scale in 2022 in Lancet Planetary Health.

Prompted by Young’s research, Lucks and his lab began to investigate naturally occurring biosensors — molecules used by microbes to sense for the presence of contaminants. In 2020, they published work on repurposing biosensors in a cell-free synthetic biology system, allowing the detection of harmful water contaminants such as fluoride in the field, naming the technology platform ROSALIND.

To further Young’s research on improving global water security, the latest iteration of the Lucks Lab’s ROSALIND technology improved the speed and usability of the device to allow for easy transport to locations where harmful levels of fluoride are a safety concern.

The research team collected 57 water samples from 36 households in rural Kenya to evaluate the accuracy of the fluoride concentration measurement when compared with the gold-standard method of fluoride photometer. They also designed their studies to examine whether test results would be easily interpreted by non-expert users, a key indicator that the technology can have meaningful impact in addressing the global water crisis.

Results were excellent, showing that the point-of-use had an 84% chance of correctly predicting fluoride levels above the World Health Organization limit of more than 1.5 parts per million.

The tests also were found to be highly usable, with only 1 of 57 tests with an interpretation discrepancy between the user and scientific team.

“This is a whole new way to measure water quality,” Young said. “The study shows that we can get a test into people’s hands that is based on some very complex biology but works very simply.”

“It also points to the feasibility of such tests for other chemicals like lead and PFAS,” Lucks said.

Potential next steps for the point-of-use fluoride test could include mapping where geogenic fluoride is located globally.

Closer to home in Chicago, Young and Lucks are interested in investigating the usability of an at-home test for rapidly detecting lead in water, and in leveraging this study as a model for interfacing social sciences with synthetic biology to increase the impact of synthetic biology innovations.

The study, “The accuracy and usability of point-of-use fluoride biosensors: a field study in Nakuru County, Kenya,” will appear online Feb. 8, 2023, in Nature Partner Journals: Clean Water.

This work was supported by the Carnegie Corporation; Northwestern University’s Institute for Policy Research and the Crown Family Center for Jewish and Israel Studies; the support of the American people provided to the Feed the Future Sustainable Intensification Innovation Lab through the United States Agency for International Development Cooperative Agreement AID-OAA-L-14-00006; and the United States Army Contracting Command W52P1J-21-9-3023.

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JOURNAL

npj Clean Water

DOI

10.1038/s41545-023-00221-5 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

The accuracy and usability of point-of-use fluoride biosensors: a field study in Nakuru County, Kenya

ARTICLE PUBLICATION DATE

8-Feb-2023

Artificial sweetener as wastewater tracer

New study by the University of Vienna shows what the sweetener acesulfame reveals about groundwater flows

Peer-Reviewed Publication

UNIVERSITY OF VIENNA

Acesulfame is a sweetener in sugar-free drinks and foods. As it cannot be metabolised in the human body, the sweetener ends up in wastewater after consumption and remains largely intact even in sewage treatment plants. A new study by the University of Vienna shows that the persistence of the sweetener varies with temperature as the concentration of the sweetener in wastewater varies with the seasons. The environmental geosciences team analysed how groundwater flows can be traced based on these seasonal fluctuations. Since residues of the sweetener end up in drinking water, acesulfame serves as an indicator of the origin and composition of our drinking water. The study has now been published in the journal Water Research.

The sugar substitute acesulfame is one of the most commonly used sweeteners in Europe. It is almost 200 times sweeter than sugar and temperature-stable, making it suitable for sugar-free baking and for sweetening most diet lemonades. Because the human body does not metabolise the substance, it ends up in wastewater when consumed in large quantities and remains there even after treatment, but in fluctuating concentrations. The new study by the University of Vienna shows that the substance is broken down to varying degrees over the year depending on the temperature. "For a long time, it was assumed that the potassium salt of acesulfame is not degraded at all in wastewater treatment plants. This is still true, but only in the cold season," explains Thilo Hofmann, deputy head of the Centre for Microbiology and Environmental Systems Science at the University of Vienna. "There were already initial indications that at least partial biodegradation takes place in summer. We can prove this in our study and systematically show for a longer period of time how the concentration of the sweetener in the water changes with the seasons."

Sweetener acesulfame: indicator for the flow paths of wastewater treated in sewage treatment plants

Acesulfame is a widely used indicator of wastewater discharges into surface waters and groundwater: since this sweetener is not completely degraded both in wastewater treatment plants and in the environment – after it has been discharged into water bodies with the treated wastewater – a detection of the substance in water indicates that and how much treated wastewater has entered groundwater, rivers or lakes. "If you follow the traces of the substance, you can ultimately trace flow paths of the wastewater and its mixing with groundwater," Hofmann explains. With the knowledge of seasonal fluctuations in the degradation of the substance, acesulfame becomes an even more meaningful tracer.

Computer models of groundwater flows enable risk prevention

"Our study shows that the seasonally fluctuating concentration of acesulfame can be used to better visualise and understand the processes in the subsurface, i.e. groundwater flows," says Hofmann. Wastewater components in drinking water can be recorded as well as the flow velocity of the groundwater and the mixing ratios of groundwater and river water. The environmental geoscientists evaluated river and groundwater samples that were collected regularly over eight years in a pre-alpine catchment. The research team linked their analyses to computer models that calculate water flows in the subsurface. "Such computer models are the key to risk prevention, because they can be used to understand how much river water and how much groundwater end up in the population's drinking water and how to optimise the operation of waterworks," adds the head of the research group. 

Traces of the sweetener end up in drinking water

The sweetener acesulfame thus lays a tracer trail from wastewater to river and groundwater and finally to our drinking water. "The fact that acesulfame is not degraded is basically a good thing for us hydrogeologists, because we can draw valuable information from it," says Hofmann. He adds: "However, this fact also makes us aware of our lifestyle being reflected in the wastewater and thus also in the drinking water: The sugar substitute we consume ends up back in our drinking water – albeit heavily diluted, of course."

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JOURNAL

Water Research

DOI

10.1016/j.watres.2023.119670 

ARTICLE TITLE

Seasonal biodegradation of the artificial sweetener acesulfame enhances its use as a transient wastewater tracer

New evolutionary insights from stepping outside the lab

In order to study fruit fly phenotypes, EMBL´s Crocker group uses unusual approaches to uncover surprising results

Peer-Reviewed Publication

EUROPEAN MOLECULAR BIOLOGY LABORATORY

 

IMAGE: EMBL SCIENTISTS JUSTIN CROCKER AND LAUTARO GANDARA USED FOOD SOURCES INCORPORATING FRUIT GROWN IN AND AROUND EMBL IN THEIR EXPERIMENTS THAT BRIDGE NATURAL AND LAB ENVIRONMENTS TO UNDERSTAND THE EVOLUTION OF PHENOTYPES. view more 

CREDIT: EMBL/ KINGA LUBOWIECKA

Most of his career, Justin Crocker, EMBL Heidelberg Group Leader, has been working at the interface of development and evolution. In two new studies led by Crocker, scientists have shown how using non-standard laboratory conditions and synthetic biology approaches can help us understand fundamental mechanisms that regulate the development and evolution of phenotypes.

In this, they are part of the growing field of phenomics – the systematic study of an organism’s traits and how they vary and change during development as well as in response to the environment. Phenotypic evolution becomes particularly interesting in light of global concerns such as climate change, where many animals are under pressure to adapt quickly to fast-changing environments.

The significance of studying phenotypes

Phenotypes are the observable characteristics of an organism – features such as behaviour, appearance, metabolism, gene expression patterns, etc. They result from interactions between the genotype – the information contained in DNA, and the environment. The phenotypes any organism exhibits often depend on precise decisions regarding which genes are expressed where and when.

In the two publications, the Crocker group and their collaborators provide novel insights into some of the key processes that determine the robustness of phenotypes and the appearance of new phenotypes during development. 

This knowledge can help researchers better understand how diversity emerges during evolution in animals, and perhaps even predict ecological and environmental patterns of change in the phenotypes of wild animal populations.

Studying phenotypes in laboratories vs “the wild”

Biologists often study organisms under well-standardised laboratory conditions to ensure rigour and reproducibility. However, this also increases the risk of missing effects that only become apparent outside of these narrow ranges of conditions.

Using fruit-fly embryos and a variety of other model systems, Crocker and his team have been demonstrating  the importance of moving beyond standardised laboratory conditions and challenging established assumptions when it comes to understanding the development and evolution of phenotypes. 

The team used food sources incorporating fruit grown in and around the EMBL Heidelberg campus in their experiments that bridge natural and lab environments to understand the evolution of phenotypes.

In their experiments, they found that the loss of a certain epigenetic mark, the H3K4 monomethylation, led to changes in behaviour, gene expression, metabolism, and even rates of offspring production.

“This epigenetic mark is present throughout the genome, but its deletion seems to have little to no impact on gene expression, which led scientists to hypothesise that it doesn’t play a major role in normal development and function,” said first co-author Albert Tsai, team leader at the Centre de Recherche en Biologie cellulaire de Montpellier (CRBM), former postdoc in the Crocker lab.

H3K4 monomethylation is found ubiquitously in almost every cell’s nucleus. “That led us to question why there is such an evolutionary drive to create these marks if it’s actually doing nothing,” said Tsai. The Crocker group was sure that they were missing something.

The scientists observed that the loss of H3K4 monomethylation led to changes, especially when the fruit-flies were fed on natural food sources, including fruit collected in and around the EMBL campus. In the absence of this mark, certain traits became sensitive to environmental conditions and to different genetic backgrounds. When exposed to high temperatures or when certain background genes were mutated, the organisms likewise responded differently. 

“It challenges the current paradigm of standardising experiments as much as possible to focus on very specific conditions,” said Tsai. “We need to come up with controlled ways of bringing more natural environments into the lab.”

Synthetic biology and the study of phenotypes

In a second study, Crocker and his team questioned how new phenotypes emerge in the first place. This is a central question in evolutionary biology – for organisms to accumulate small changes that would be selected by the environment, there must be a way to continuously, quickly, and easily introduce variation in phenotypes.

While our genomes often accumulate small changes – called mutations – over time, these don’t always result in changes in phenotypes, or observable traits.

The team began by studying the expression of various genes in fruit fly embryos with point mutations – single-nucleotide DNA changes – in enhancer regions of the genome. “What we quickly started to appreciate was that while gene expression levels changed in these mutants, it always remained within the same regions,” said Rafael Galupa, first author of the paper and former postdoc in the Crocker lab. In other words, if a gene is usually active in the gut, for example, its expression levels increased or decreased as a result of the mutations, but did not shift to a different tissue, e.g. the muscle. “So we started wondering, what does it take to get expression elsewhere?” said Galupa, who is currently on his way to establishing his independent lab in Centre de Biologie Intégrative, Toulouse (France). “Ultimately in the course of evolution, how do you get new functions?”

Next, the team introduced completely random sequences into the genome instead. In a natural context, random DNA sequences may arise in the genome due to viruses, or transposons – mobile genetic elements that actively move between different parts of the genome. 

To the researchers’ surprise, with their synthetic DNA approach, they found that random sequences easily drove gene expression, and in all parts of the embryo.

 “We have been talking about doing this for a long time, and everybody thought it was a bit crazy. Then we just went ahead and did it,” said Crocker. “In the field we often think about how expression is generated, how to activate genes, etc. This study makes us think that if any random sequence can drive expression, and we have a genome with millions of sequences – maybe the question is not so much how do you generate expression but how do you repress or control it.”

In future studies, the Crocker lab will continue to look deeply into the mechanisms that connect genotype and environment to phenotypes.

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JOURNAL

Developmental Cell

DOI

10.1016/j.devcel.2022.12.003 

METHOD OF RESEARCH

Experimental study

ARTICLE TITLE

Enhancer architecture and chromatin accessibility constrain phenotypic space during Drosophila development.