Comparing physician and AI chatbot responses to patient questions

Peer-Reviewed Publication

JAMA NETWORK

About The Study: In this study of 195 randomly drawn patient questions from a social media forum, a team of licensed health care professionals compared physician’s and chatbot’s responses. The chatbot responses were preferred over physician responses and rated significantly higher for both quality and empathy. Further exploration of this technology is warranted in clinical settings, such as using chatbot to draft responses that physicians could then edit. Randomized trials could assess further if using AI assistants might improve responses, lower clinician burnout, and improve patient outcomes. 

Authors: John W. Ayers, Ph.D., M.A., of the University of California San Diego, La Jolla, is the corresponding author.

(doi:10.1001/jamainternmed.2023.1838)

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.

 https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/10.1001/jamainternmed.2023.1838?guestAccessKey=cc017939-cb8d-4cf0-bf64-11492a83ade0&utm_source=For_The_Media&utm_medium=referral&utm_campaign=ftm_links&utm_content=tfl&utm_term=042823

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JOURNAL

JAMA Internal Medicine

Study finds ChatGTP outperforms physicians in providing high-quality, empathetic advice to patient questions

While AI won’t replace your doctor, the JAMA Internal Medicine paper suggests physicians working together with technologies like ChatGPT may revolutionize medicine

Peer-Reviewed Publication

UNIVERSITY OF CALIFORNIA - SAN DIEGO

La Jolla, Calif. (April 28, 2023) — There has been widespread speculation about how advances in artificial intelligence (AI) assistants like ChatGPT could be used in medicine. 

A new study published in JAMA Internal Medicine led by Dr. John W. Ayers from the Qualcomm Institute within the University of California San Diego provides an early glimpse into the role that AI assistants could play in medicine. The study compared written responses from physicians and those from ChatGPT to real-world health questions. A panel of licensed healthcare professionals preferred ChatGPT’s responses 79% of the time and rated ChatGPT’s responses as higher quality and more empathetic. 

“The opportunities for improving healthcare with AI are massive,” said Ayers, who is also vice chief of innovation in the UC San Diego School of Medicine Division of Infectious Disease and Global Public Health. “AI-augmented care is the future of medicine.” 

Is ChatGPT Ready for Healthcare?

In the new study, the research team set out to answer the question: Can ChatGPT respond accurately to questions patients send to their doctors? If yes, AI models could be integrated into health systems to improve physician responses to questions sent by patients and ease the ever-increasing burden on physicians.

“ChatGPT might be able to pass a medical licensing exam," said study co-author Dr. Davey Smith, a physician-scientist, co-director of the UC San Diego Altman Clinical and Translational Research Institute and professor at the UC San Diego School of Medicine, “but directly answering patient questions accurately and empathetically is a different ballgame.” 

“The COVID-19 pandemic accelerated virtual healthcare adoption,” added study co-author Dr. Eric Leas, a Qualcomm Institute affiliate and assistant professor in the UC San Diego Herbert Wertheim School of Public Health and Human Longevity Science. “While this made accessing care easier for patients, physicians are burdened by a barrage of electronic patient messages seeking medical advice that have contributed to record-breaking levels of physician burnout.”

Designing a Study to Test ChatGPT in a Healthcare Setting

To obtain a large and diverse sample of healthcare questions and physician answers that did not contain identifiable personal information, the team turned to social media where millions of patients publicly post medical questions to which doctors respond: Reddit’s AskDocs. 

r/AskDocs is a subreddit with approximately 452,000 members who post medical questions and verified healthcare professionals submit answers. While anyone can respond to a question, moderators verify healthcare professionals’ credentials and responses display the respondent’s level of credentials. The result is a large and diverse set of patient medical questions and accompanying answers from licensed medical professionals.

While some may wonder if question-answer exchanges on social media are a fair test, team members noted that the exchanges were reflective of their clinical experience. 

The team randomly sampled 195 exchanges from AskDocs where a verified physician responded to a public question. The team provided the original question to ChatGPT and asked it to author a response. A panel of three licensed healthcare professionals assessed each question and the corresponding responses and were blinded to whether the response originated from a physician or ChatGPT. They compared responses based on information quality and empathy, noting which one they preferred.

The panel of healthcare professional evaluators preferred ChatGPT responses to physician responses 79% of the time. 

“ChatGPT messages responded with nuanced and accurate information that often addressed more aspects of the patient’s questions than physician responses,” said Jessica Kelley, a nurse practitioner with San Diego firm Human Longevity and study co-author.   

Additionally, ChatGPT responses were rated significantly higher in quality than physician responses: good or very good quality responses were 3.6 times higher for ChatGPT than physicians (physicians 22.1% versus ChatGPT 78.5%). The responses were also more empathic: empathetic or very empathetic responses were 9.8 times higher for ChatGPT than for physicians (physicians 4.6% versus ChatGPT 45.1%). 

“I never imagined saying this,” added Dr. Aaron Goodman, an associate clinical professor at UC San Diego School of Medicine and study coauthor, “but ChatGPT is a prescription I’d like to give to my inbox. The tool will transform the way I support my patients.”

Harnessing AI Assistants for Patient Messages  

“While our study pitted ChatGPT against physicians, the ultimate solution isn’t throwing your doctor out altogether,” said Dr. Adam Poliak, an assistant professor of Computer Science at Bryn Mawr College and study co-author. “Instead, a physician harnessing ChatGPT is the answer for better and empathetic care.”

“Our study is among the first to show how AI assistants can potentially solve real world healthcare delivery problems,” said Dr. Christopher Longhurst, Chief Medical Officer and Chief Digital Officer at UC San Diego Health. “These results suggest that tools like ChatGPT can efficiently draft high quality, personalized medical advice for review by clinicians, and we are beginning that process at UCSD Health.” 

Dr. Mike Hogarth, a physician-bioinformatician, co-director of the Altman Clinical and Translational Research Institute at UC San Diego, professor in the UC San Diego School of Medicine and study co-author, added, “It is important that integrating AI assistants into healthcare messaging be done in the context of a randomized controlled trial to judge how the use of AI assistants impact outcomes for both physicians and patients.”  

In addition to improving workflow, investments into AI assistant messaging could impact patient health and physician performance. 

Dr. Mark Dredze, the John C Malone Associate Professor of Computer Science at Johns Hopkins and study co-author, noted: “We could use these technologies to train doctors in patient-centered communication, eliminate health disparities suffered by minority populations who often seek healthcare via messaging, build new medical safety systems, and assist doctors by delivering higher quality and more efficient care.” 

In addition to Ayers, Poliak, Dredze, Leas, Kelley, Goodman, Longhurst, Hogarth and Smith, authors of the JAMA Internal Medicine paper, “Comparing Physician and Artificial Intelligence Chatbot Responses to Patient Questions Posted to a Public Social Media Forum” (JAMA Intern Med. doi:10.1001/jamainternmed.2023.1838), are Zechariah Zhu of  UC San Diego and Dr. Dennis J. Faix of the Naval Health Research Center. 

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JOURNAL

JAMA Internal Medicine

DOI

10.1001/jamainternmed.2023.1838 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Comparing Physician and Artificial Intelligence Chatbot Responses to Patient Questions Posted to a Public Social Media Forum

ARTICLE PUBLICATION DATE

28-Apr-2023

COI STATEMENT

Disclosures as reported in the paper: Dr Ayers reported owning equity in companies focused on data analytics, Good Analytics, of which he was CEO until June 2018, and Health Watcher. Dr Dredze reported personal fees from Bloomberg LP and Sickweather outside the submitted work and owning an equity position in Good Analytics. Dr Leas reported personal fees from Good Analytics during the conduct of the study. Dr Goodman reported personal fees from Seattle Genetics outside the submitted work. Dr Hogarth reported being an advisor for LifeLink, a health care chatbot company. Dr Longhurst reported being an advisor and equity holder at Doximity. Dr Smith reported stock options from Linear Therapies, personal fees from Arena Pharmaceuticals, Model Medicines, Pharma Holdings, Bayer Pharmaceuticals, Evidera, Signant Health, Fluxergy, Lucira, and Kiadis outside the submitted work. No other disclosures were reported.

Treatment of children with ADHD

Peer-Reviewed Publication

JAMA NETWORK

About The Study: The results of this study of children with parent-reported attention-deficit/hyperactivity disorder (ADHD) suggest that most were not receiving ADHD medications and had never received outpatient mental health care. Gaps in treatment, which were not directly associated with socioeconomic disadvantage, underscore the challenges of improving communication and access to outpatient mental health care for children with ADHD. 

Authors: Mark Olfson, M.D., M.P.H., of Columbia University and the New York State Psychiatric Institute in New York, is the corresponding author. 

(doi:10.1001/jamanetworkopen.2023.10999)

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.

#  #  #

 http://jamanetwork.com/journals/jamanetworkopen/fullarticle/10.1001/jamanetworkopen.2023.10999?utm_source=For_The_Media&utm_medium=referral&utm_campaign=ftm_links&utm_term=042823

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

Bentley University study shows NIH investment in new drug approvals is comparable to investment by pharmaceutical industry

Government provides early investment in pharmaceutical innovation

Peer-Reviewed Publication

BENTLEY UNIVERSITY

BENTLEY UNIVERSITY

The National Institutes of Health (NIH) spent $187 billion for basic or applied research related to 354 of the 356 drugs approved by the FDA from 2010-2019, according to a new study from Bentley University’s Center for Integration of Science and Industry. The study, published in JAMA Health Forum, shows that the amount invested per approved drug by the NIH is comparable to that of reported investment by the biopharmaceutical industry. The article, titled “Comparison of research spending on new drug approvals by the U.S. National Institutes of Health versus industry, 2010-2019,” is the first to compare the total value of NIH and industry investments taking into account actual spending on research related to approved products and failed product candidates as well as the time-value of these investments.

This paper estimated actual NIH spending of $1.4 billion for each approved first-in-class drug. The Tufts Center for the Study of Drug Development (CSDD) has estimated actual industry spending to be $1.5 billion per approved drug. Considering also a 3% annual discount, per drug investment by the NIH was $1.7 billion. NIH spending provided cost savings to industry of $2.9 billion per approved drug (calculated with a 10.5% annual cost of capital), which is comparable to the Tufts CSDD estimate of $2.8 billion industry investment in each approved drug. This work shows the government served as an early investor in pharmaceutical innovations that are subsequently launched and commercialized by industry.

“Our analysis shows that at least half of the total investment in research and development required to bring a product to market comes from the U.S. government,” said Fred Ledley, Director of the Center for Integration of Science and Industry, and the senior author on this study. “If taxpayers are investing as much as shareholders in bringing drugs to market, then the public could expect social or economic returns commensurate with those of pharmaceutical companies or their shareholders.”

Industry has been criticized for high drug prices that make needed drugs unavailable to some patients. While industry claims that high drug prices are justified by the cost of bringing these drugs to market, the present work suggests that the public interest in these products should be balanced with corporate interest.

The Bentley study identified NIH funding for more than 400,000 research publications related to the drugs approved by the FDA from 2010-2019. Total NIH spending was $187 billion, with 83% of this total involving basic research on drug targets and 17% involving applied research on the drugs themselves. Statistical comparison of NIH investments in 60 drugs with industry costs reported from the London School of Economics and Political Science show NIH investment was not less than industry investment. This analysis also examined the economic efficiencies created by public sector funding for basic research that may provide a foundation for multiple product approvals. Considering that NIH-funded research on a validated drug target will be associated with an average of 2.85 drugs, the NIH invested an average of $711 million per drug approved 2010-2019.

Dr. Ekaterina Galkina Cleary was the lead author of this work along with Dr. Matthew Jackson and Dr. Edward Zhou.

This work was supported by grants from the Institute for New Economic Thinking and the National Biomedical Research Foundation.

THE CENTER FOR INTEGRATION OF SCIENCE AND INDUSTRY at Bentley University focuses on advancing the translation of scientific discoveries to create public value. The Center is an environment for interdisciplinary scholarship spanning basic science, data analytics, business, and public policy. For more information, visit www.bentley.edu/sciindustry and follow us on Twitter @sciindustry and LinkedIn.

BENTLEY UNIVERSITY is more than just one of the nation's top business schools. It is a lifelong-learning community that creates successful leaders who make business a force for positive change. With a combination of business and the arts and sciences and a flexible, personalized approach to education, Bentley provides students with critical thinking and practical skills that prepare them to lead successful, rewarding careers. Founded in 1917, the university enrolls 4,100 undergraduate and 1,000 graduate and PhD students and is set on 163 acres in Waltham, Massachusetts, 10 miles west of Boston. For more information, visit bentley.edu. For more information, visit bentley.edu. Follow us on Twitter @BentleyU #BentleyUResearch.

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JOURNAL

JAMA Health Forum

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Comparison of research spending on new drug approvals by the U.S. National Institutes of Health versus industry, 2010-2019

ARTICLE PUBLICATION DATE

28-Apr-2023

COI STATEMENT

Drs Jackson, Galkina Cleary, and Ledley reported grants from the National Biomedical Research Foundation and Institute for New Economic Thinking during the conduct of the study as well as grants from the West Health Policy Center and National Pharmaceutical Council outside the submitted work. Dr Zhou reported grants from the National Biomedical Research Foundation during the conduct of the study as well as a grant from the National Pharmaceutical Council outside the submitted work. No other disclosures were reported.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of n

How solid air can spur sustainable development

Peer-Reviewed Publication

INTERNATIONAL INSTITUTE FOR APPLIED SYSTEMS ANALYSIS

 

IMAGE: SOLID AIR HYDROGEN LIQUEFACTION view more 

CREDIT: HUNT ET AL.

The green hydrogen economy is a sustainable alternative to fossil fuels. However, one of the challenges of constructing a global hydrogen economy is hydrogen transportation by sea. A new paper proposes solid air as a medium for recycling cold energy across the hydrogen liquefaction supply chain.

The world is undergoing an energy transition to reduce CO2 emissions and mitigate climate change. The COVID-19 pandemic and the Russia-Ukraine war have further increased the interest of Europe and Western countries to invest in the hydrogen economy as an alternative to fossil fuels. Hydrogen can significantly reduce geopolitical risks if the diversity of future hydrogen energy suppliers is increased.

Hydrogen is a particularly challenging product to transport safely. One option is to liquefy hydrogen, which requires cooling to 20 Kelvin (-253 °C). This is an expensive process and requires around 30% of the energy stored within the hydrogen.

A pioneering approach developed by IIASA researchers and colleagues proposes solid air (nitrogen or oxygen) as a medium for recycling cooling energy across the hydrogen liquefaction supply chain. At standard temperature and pressure, air is a gas, but under certain conditions, it can become a liquid or solid. Solid Air Hydrogen Liquefaction (SAHL) consists of storing the cooling energy from the regasification of hydrogen, by solidifying air, and transporting the solid air back to where the hydrogen was liquefied. The solid air is then used to reduce the energy consumption for liquefying hydrogen. The process is divided into four main steps: hydrogen regasification, solid air transportation, hydrogen liquefaction, and liquid hydrogen transportation.

Another advantage of solidifying air for energy recovery in the hydrogen liquefaction supply chain is the extra production of oxygen. The oxygen could be used to increase the efficiency of power generation with oxy-combustion and to facilitate the capture, use, and storage of carbon (CCUS).

“Using solid air as a medium for recycling cooling energy across the hydrogen liquefaction supply chain can reduce the cost and energy consumption for transporting hydrogen between continents,” says lead author Julian Hunt, a researcher in the Integrated Assessment and Climate Change Research Group of the IIASA Energy, Climate, and Environment Program. “This would increase the viability of a global hydrogen economy in the future and increase the number of hydrogen suppliers for energy-demanding regions, such as China, Europe, and Japan. The possibility of selling hydrogen could result in a further expansion of solar and wind power in developing countries, contributing to their economies.”

In their paper, the authors also address the ongoing debate in industry and academia to find the best alternative to transport hydrogen by sea:

“Compared to ammonia or methanol, liquefied hydrogen is the best option for several reasons. Transporting hydrogen with ammonia and other molecules would require around 30% of the energy transported to extract the hydrogen. The hydrogen is liquefied where electricity is cheap. Also, SAHL can lower energy consumption for hydrogen liquefaction by 25 to 50%,” Hunt concludes.

Reference

Hunt, J., Montanari, P., Hummes D., Taghavi M., Zakeri, B., Romero, O., Zhou, W., Castro, J., Schneider, P., Wada, Y. (2023). Solid air hydrogen liquefaction, the missing link of the hydrogen economy. International Journal of Hydrogen Energy DOI: https://doi.org/10.1016/j.ijhydene.2023.03.405 

 

About IIASA:

The International Institute for Applied Systems Analysis (IIASA) is an international scientific institute that conducts research into the critical issues of global environmental, economic, technological, and social change that we face in the twenty-first century. Our findings provide valuable options to policymakers to shape the future of our changing world. IIASA is independent and funded by prestigious research funding agencies in Africa, the Americas, Asia, and Europe.

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JOURNAL

International Journal of Hydrogen Energy

DOI

10.1016/j.ijhydene.2023.03.405 

ARTICLE TITLE

Solid air hydrogen liquefaction, the missing link of the hydrogen economy

ARTICLE PUBLICATION DATE

27-Apr-2023

York University leads $318.4M first-of-kind inclusive next-gen technology research initiative

Together with Queen’s University, the cross-disciplinary work is backed by $105.7M in federal funding through the Canada First Research Excellence Fund

Grant and Award Announcement

YORK UNIVERSITY

TORONTO, April 28, 2023 — Is an equitable world that includes humans and machines possible? York University researchers believe it must be and have set out to make it so through a first of its kind interdisciplinary research initiative called Connected Minds: Neural and Machine Systems for a Healthy, Just Society.

From universities to industries, hospitals and policymakers, artists and Indigenous communities, York’s Connected Minds will engage 50+ community partners and research collaborators over seven years supported by a historic $318.4 million in funding. Connected Minds has received a combined $105.7 million from the Canada First Research Excellence Fund (CFREF), announced earlier today by the Government of Canada. Of that, York received $82.8 million and institutional partner Queen’s University received $22.8 million.

Led by York, Connected Minds brings together experts in multiple fields, including humanities, engineering, law, and life sciences, located across eight York Faculties and three Queen’s Faculties. Researchers will examine the ways in which emerging technology, like Artificial Intelligence, is transforming and entangling society – dubbed the ‘techno-social collective.’ Researchers will work to discover how to balance both the potential risks and benefits for humanity.  

Some of the program’s proposed projects include explorations into a more inclusive metaverse, virtual reality and community organizing, neurotechnologies for healthy aging, Indigenous data sovereignty, and how human brain function changes when people interact with AI versus each other.  

In addition to supporting interdisciplinary teams of researchers conducting research on promoting a healthy, resilient, and just techno-social collective, Connected Minds will fund 35 strategic faculty hires, partner-focused seed, team, and prototyping grants, knowledge mobilization and commercialization activities, and an ambitious multi-institutional micro-credential training program with 385 trainees and cross-sector stakeholders. All activities will require interdisciplinary participation, and projects that benefit Indigenous and other equity-deserving groups will be prioritized.

A key structural component of the program is an Indigenous-led focus and will feature a dedicated Indigenous research space on York’s Keele Campus, as well as employing an overarching decolonization, equity, diversity and inclusion (DEDI) strategy.

The program’s operations will involve a directorate led by internationally renowned neuroscientist Prof. Doug Crawford, as Scientific Director, along with intellectual property and technology law expert Prof.  Pina D’Agostino, as Vice-Director and Indigenous health scholar Prof. Sean Hillier as Associate Director. Engineer and neuroscientist Prof. Gunnar Blohm joins as the Vice-Director from Queen’s University.  

The governance structure of Connected Minds includes a Board of Directors to supervise the program ramp up, oversee its progress towards achieving strategic goals and maintain fiduciary responsibility, an External Advisory Board to advise on the overall strategic direction, knowledge mobilization and commercialization activities, and an Indigenous Advisory Circle to counsel all aspects of Indigenous engagement, including issues of privacy and data sovereignty.

The total value of the Connected Minds projects is $318.4 million with the remaining funds, including in-kind contributions, being contributed largely by multi-sector partners, municipal governments, and collaborating institutions.

QUOTES

“Receiving this second CFREF award in the last two competitions reflects York’s leadership as a research-intensive university that from its inception has understood the importance of an interdisciplinary approach in tackling complex, global problems. Connected Minds is particularly timely as we consider the implications of AI for creating a more equitable and inclusive world.” – Rhonda Lenton, York University president and vice-chancellor

“York is an international leader in interdisciplinary research involving artificial intelligence and other disruptive technologies, social justice, and human science like neuroscience, philosophy, and psychology. The government’s substantial investment will unite York’s incredible strengths with Queen’s health specialties to chart new territory in socially responsible, community-engaged research for a rapidly changing digital world.” – Amir Asif, York University vice-president, Research and Innovation

“The current technological revolution will have transformative positive impacts, and likely unintended negative impacts, on humanity for generations to come. To predict these impacts and steer toward positive outcomes, one requires transdisciplinary expertise, multisector community engagement, and research and training at levels that can only occur in a large-scale program. We thank CFREF for providing Connected Minds with the resources to lead Canada and the world in this timely and critical enterprise.” – Doug Crawford, York Distinguished Research Professor in Neuroscience and inaugural Scientific Director of Connected Minds 

“New technologies are developing exponentially and systems like the law are simply not keeping up. York University’s motto, tentanda via, the way must be tried, guides us, in everything we will do.  We believe our inclusive, interdisciplinary approach that aligns with the UN sustainable development goals makes York University the perfect place for anticipating the way humans and machines will, and should, connect in an equitable society.  This way must be tried.” – Pina D’Agostino, director and founder of York’s IP Innovation Clinic at Osgoode Hall Law School and Vice Director of Connected Minds. 

“Connected Minds is informed by Indigenous perspectives and priorities to achieve outcomes that are culturally relevant and responsive to Indigenous ways of being and doing that impact how we think about and engage in life, health, and education. Our work will seek to address the unexpected consequences of technological innovation, like the growing digital divide for Indigenous communities to access remote health care, and issues of data sovereignty, ownership and digital colonialism.” – Sean Hillier, director of York University’s Centre for Indigenous Knowledges & Languages and Associate Director of Connected Minds

“The Connected Minds project builds on a history of partnership and collaboration between Queen’s and York. Each institution brings unique but complementary research strengths to bear on the important challenges and opportunities that come with disruptive technologies and their impact on Canadian and global citizens.”— Nancy Ross, vice principal research at Queen’s University

“I look forward to working with Indigenous, community and industrial partners to develop more equitable and socially responsible research outputs for the benefit of all. I am also excited about the many educational and outreach opportunities that Connected Minds will produce – from school programs to graduate training and professional skills development. We want to democratize education and access to knowledge, with the aim of spreading a new culture of innovation for a more equitable, inclusive, and healthy society.” – Gunnar Blohm, Professor in Computational Neuroscience and Vice Director of Connected Minds

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Vascular plants colonized land extensively by the early Silurian: Study

Peer-Reviewed Publication

CHINESE ACADEMY OF SCIENCES HEADQUARTERS

 

IMAGE: A COMPILATION OF (A) Δ199HG AND (B) Δ200HG FOR PALEOZOIC SEDIMENTS AT THE STAGE LEVEL view more 

CREDIT: IGCAS

The colonization and expansion of plants on land represent a defining landmark for the path of life on Earth. Terrestrial colonization has been attributed to a series of major innovations in plant body plans, anatomy, and biochemistry that transformed global biogeochemical cycles and climates.

It is crucial to identify the onset and track the expansion of those earliest land plants. However, the precise timing of land colonization by vascular plants remains controversial due to the sparseness of early land plant megafossils, poor stratigraphic controls on their distribution, and the uncertainties associated with molecular clock calculations.

Recently, scientists led by Prof. CHEN Daizhao from the Institute of Geology and Geophysics and Prof. FENG Xinbin from the Institute of Geochemistry of the Chinese Academy of Sciences (CAS) used mercury isotope to prove that vascular plants had already extensively colonized land by the early Silurian (~444 Ma).

This work was published in Science Advances on April 28.

Researchers from the Xishuangbanna Tropical Botanical Garden of CAS, the Nanjing Institute of Geology and Palaeontology of CAS, the Chinese Geological Survey, the Open University, UK, and the College of Charleston, USA, were also involved in the study.

Mercury (Hg) is the only heavy metal element that is liquid under natural conditions. It is also transported globally in gaseous elemental form (Hg0) via atmospheric circulation. The most important realization about modern forest Hg cycling in recent decades has been that Hg in vegetation is derived from atmospheric Hg0 assimilation via leaves rather than from precipitation Hg or geologic Hg transport.

Land vegetation preferentially transfers atmospheric Hg0, which displays distinct negative odd mass independent fractionation (odd-MIF, reported as Δ199Hg) and even-MIF (reported as Δ200Hg) signatures, into terrestrial ecosystems. As land plants expanded and affected weathering in terrestrial settings, Hg containing these unique negative Δ199Hg and Δ200Hg values would be transported to nearshore marine environments, which showed significant positive signatures primally. Therefore, the geologic record of these isotopic systems potentially provides a novel tracer to track the colonization and expansion of plants on land.

In this study, the researchers used Hg stable isotope data from marine sediments spanning the Cambrian to Permian from different depositional facies collected from South China to highlight two episodes of distinct negative excursions in both odd- and even-MIF values at the stage level in the Silurian and Carboniferous.

They established a numerical model to quantify secular variations in the contribution from terrestrial organisms for the Paleozoic. They found that the results pushed back in time the extensive spread of early vascular plants to ~444 Ma in the early Silurian, at least in low-latitude areas like South China—a time period that is significantly earlier than the first known macrofossil of a vascular plant.

The study linked the Paleozoic expansion of terrestrial organisms, notably vascular plants, to the co-evolution of a range of earth systems, particularly those of the atmosphere, oceans, weathering processes, and geochemical features.

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JOURNAL

Science Advances

DOI

10.1126/sciadv.ade9510 

ARTICLE TITLE

Mercury isotopes show vascular plants had colonized land extensively by the early Silurian

ARTICLE PUBLICATION DATE

28-Apr-2023

https://en.wikipedia.org/wiki/Silurian_(Doctor_Who)

Silurian (Doctor Who) - Wikipedia 

The Silurians are a race of reptilian humanoids in the long-running British science fiction television series Doctor Who. The species first appeared in ...

Shocking implications of electric fishes’ tailless sperm

Grant and Award Announcement

MICHIGAN STATE UNIVERSITY

 

IMAGE: THE SPERM OF THE MORMYRID WEALY ELECTRIC FISH IS THE ONLY KNOWN VERTEBRATE SPECIES THAT LACKS FLAGELLUM. PANEL A SHOWS A LIGHT MICROSCOPE IMAGE OF A SPERM SAMPLE: THE SPERM ARE COMPLETELY IMMOTILE. PANEL B SHOWS A SCANNING ELECTRON MICROSCOPE IMAGE OF A SINGLE SPERM CELL. view more 

CREDIT: JASON GALLANT, MICHIGAN STATE UNIVERSITY

Betting on tailless sperm that evolved from brave swimmers to hapless floaters seems like a crazy evolutionary gamble, but a group of fish seems to have done just that. Understanding that tradeoff holds promise to shed light on human disease and shake up biology lessons on traditional gender roles.

Michigan State University associate professor of integrative biology Jason Gallant and colleagues are using nearly $1 million from the National Science Foundation to understand the implications from a small African fish which evolved to have sperm with no tails but an electric-powered mating call. 

“We want to know why electric fish get away with it when no other vertebrate can,” said Gallant, a member of MSU’s Ecology, Evolution, and Behavior Program. “A general notion in biology is that sperm are cheap, and eggs are expensive – but these fish may be telling us that sperm are more expensive than we might think. They could be saving energy by cutting back on sperm tails.” Gallant is part of MSU’s College of Natural Science.

The variety of fish called mormyroids are commonly called elephantfish because even though small, their elongated mouths look a bit like a trunk. They live in murky African waters so dense they rely on brief electric charges to find each other. The pulses of electrical output and the brainpower needed to pick analyze these pulses requires a lot of energy. Elephantfish may have prioritized spending their energy stores to finding females and then on relying on other ways to deliver sperm to egg.

And within that theory are so many questions.

Members of the MSU Electric Fish Lab will work to confirm the gene they believe turns off sperm tail development. One way they test that is to isolate the gene and insert it in another species of fish with traditionally wiggly sperm to see if those tails disappear. The researchers also have developed a way to measure respiration to determine how much energy the fish save by nixing sperm tails.

And the group believes the questions go beyond fish sperm. Flagella are abundant throughout our tree of life – including in the sperm of people. Flagella are related to another beating appendage called cilia, which are shorter hair-like structures that also move.

“It’s interesting that cilia make biological world go round: flagella are really just really long cilia and many of the same parts,” Gallant said.

And this is where both human health and gender norms enter the picture.

A human genetic disorder called primary ciliary dyskinesia (PCD) brings chronic respiratory infection, abnormally positioned organs, fluid on the brain and infertility, all stemming from the lack of normally functioning cilia and flagella. The gene Gallant’s team is focusing on appears to be one of several factors in PCD, yet he notes its intriguing the mormyroids seem well and normal except for the tailless sperm. A better understanding of the function of the gene in fish could provide another piece of the PCD puzzle to understand human health problems.

And since fish that procreate with sperm that don’t swim is perplexing, the researchers are exploring how Elephantfish are far from traditionalists. A part of the research project will engage undergraduates to explore one of biology’s less-known stories.

“What’s neat about this grant is that we’re working with biology that turns our assumptions on their head,” Gallant said. “As humans we have assumptions that males are programmed to be the fertilizer. Females are passive recipients of sperm. But these sperm can’t even swim – they also have small testes, so aren’t competitive with other males.

“My pet hypothesis is that a lot of people get their ideas of how men and women should behave from biology lessons. If we teach them how diverse nature is. Will that change the way they go about acting with each other?”

Michigan State University's Jason Gallant and his team surveying a stream for electric fishes in Gabon.

CREDIT

Lauren Koenig, Michigan State Univesity

REICH WAS RIGHT

Previously unknown intracellular electricity may power biology

Newly discovered electrical activity within cells could change the way researchers think about biological chemistry

Peer-Reviewed Publication

DUKE UNIVERSITY

The human body relies heavily on electrical charges. Lightning-like pulses of energy fly through the brain and nerves and most biological processes depend on electrical ions traveling across the membranes of each cell in our body.

These electrical signals are possible, in part, because of an imbalance in electrical charges that exists on either side of a cellular membrane. Until recently, researchers believed the membrane was an essential component to creating this imbalance. But that thought was turned on its head when researchers at Stanford University discovered that similar imbalanced electrical charges can exist between microdroplets of water and air.

Now, researchers at Duke University have discovered that these types of electric fields also exist within and around another type of cellular structure called biological condensates. Like oil droplets floating in water, these structures exist because of differences in density. They form compartments inside the cell without needing the physical boundary of a membrane.

Inspired by previous research demonstrating that microdroplets of water interacting with air or solid surfaces create tiny electrical imbalances, the researchers decided to see if the same was true for small biological condensates. They also wanted to see if these imbalances sparked reactive oxygen,  “redox,” reactions like these other systems.

Appearing on April 28 in the journal Chem, their foundational discovery could change the way researchers think about biological chemistry. It could also provide a clue as to how the first life on Earth harnessed the energy needed to arise.

“In a prebiotic environment without enzymes to catalyze reactions, where would the energy come from?” asked Yifan Dai, a Duke postdoctoral researcher working in the laboratory of Ashutosh Chilkoti, the Alan L. Kaganov Distinguished Professor of Biomedical Engineering and Lingchong You, the James L. Meriam Distinguished Professor of Biomedical Engineering.

“This discovery provides a plausible explanation of where the reaction energy could have come from, just as the potential energy that is imparted on a point charge placed in an electric field,” Dai said.

When electric charges jump between one material and another, they can produce molecular fragments that can pair up and form hydroxyl radicals, which have the chemical formula OH. These can then pair again to form hydrogen peroxide (H2O2) in tiny but detectable amounts.

“But interfaces have seldom been studied in biological regimes other than the cellular membrane, which is one of the most essential part of biology,” said Dai. “So we were wondering what might be happening at the interface of biological condensates, that is, if it is an asymmetric system too.”

Cells can build biological condensates to either separate or trap together certain proteins and molecules, either hindering or promoting their activity. Researchers are just beginning to understand how condensates work and what they could be used for.

Because the Chilkoti laboratory specializes in creating synthetic versions of naturally occurring biological condensates, the researchers were easily able to create a test bed for their theory. After combining the right formula of building blocks to create minuscule condensates, with help from postdoctoral scholar Marco Messina in? Christopher J. Chang’s group at the University of California – Berkeley, they added a dye to the system that glows in the presence of reactive oxygen species.

Their hunch was right. When the environmental conditions were right, a solid glow started from the edges of the condensates, confirming that a previously unknown phenomenon was at work. Dai next talked with Richard Zare, the Marguerite Blake Wilbur Professor of Chemistry at Stanford, whose group established the electric behavior of water droplets. Zare was excited to hear about the new behavior in biological systems, and started to work with the group on the underlying mechanism.

“Inspired by previous work on water droplets, my graduate student, Christian Chamberlayne, and I thought that the same physical principles might apply and promote redox chemistry, such as the formation of hydrogen peroxide molecules,” Zare said. “These findings suggest why condensates are so important in the functioning of cells.”

“Most previous work on biomolecular condensates has focused on their innards,” Chilkoti said. “Yifan’s discovery that biomolecular condensates appear to be universally redox-active suggests that condensates did not simply evolve to carry out specific biological functions as is commonly understood, but that they are also endowed with a critical chemical function that is essential to cells.”

While the biological implications of this ongoing reaction within our cells is not known, Dai points to a prebiotic example of how powerful its effects might be. The powerhouses of our cells, called mitochondria, create energy for all of our life’s functions through the same basic chemical process. But before mitochondria or even the simplest of cells existed, something had to provide energy for the very first of life’s functions to begin working.

Researchers have proposed that the energy was provided by thermal vents in the oceans or hot springs. Others have suggested this same redox reaction that occurs in water microdroplets was created by the spray of ocean waves.

But why not condensates instead?

“Magic can happen when substances get tiny and the interfacial volume becomes enormous compared to its volume,” Dai said. “I think the implications are important to many different fields.”

This work was supported by the Air Force Office of Scientific Research (FA9550-20-1-0241, FA9550-21-1-0170) and the National Institutes of Health (MIRA R35GM127042; R01EB029466, R01 GM 79465, R01 GM 139245, R01 ES 28096).

CITATION: “Interface of Biomolecular Condensates Modulates Redox Reactions,” Yifan Dai, Christian F. Chamberlayne, Marco S. Messina, Christopher J. Chang, Richard N. Zare, Lingchong You, Ashutosh Chilkoti. Chem, April 28, 2023. DOI: 10.1016/j.chempr.2023.04.001

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JOURNAL

Chem

DOI

10.1016/j.chempr.2023.04.001 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Interface of Biomolecular Condensates Modulates Redox Reactions

ARTICLE PUBLICATION DATE

28-Apr-2023

'SHROOMS TALK!

Mushrooms and their post-rain, electrical conversations

Peer-Reviewed Publication

TOHOKU UNIVERSITY

 

IMAGE: MUSHROOMS IN THE FIELD WITH AN ELECTRODE ATTACHED TO THE TOP AND BOTTOM view more 

CREDIT: YU FUKASAWA

Certain fungi play a critical role in the ecological sustenance of forest trees. Ectomycorrhizal fungi are one such example. Commonly found on pine, oak, and birch trees, ectomycorrhizal fungi form a sheath around the outside of tree roots, and their mycelial body develops into vast underground networks that absorb vital nutrients from the soil and transfer it to the trees.

Scientists have been studying the possibility of electrical signal transfer between mushrooms and across trees via the mycelial networks. It is thought that fungi generate electrical signals in response to external stimuli and use these signals to communicate with each other, coordinating growth and other behavior. It has even been hypothesized that these signals can be used to help transfer nutrients to plants and trees.

Still, current scientific evidence remains sparse. Moreover, many studies have been limited to the laboratory, failing to recreate what happens in the wild.

Now, a group of researchers has recently headed to the forest floor to examine small, tan-colored ectomycorrhizal mushrooms known as Laccaria bicolor. Attaching electrodes to six mushrooms in a cluster, the researchers discovered that the electrical signals increased after rainfall.

"In the beginning, the mushrooms exhibited less electrical potential, and we boiled this down to the lack of precipitation," says Yu Fukasawa from Tohoku University, who lead the project along with Takayuki Takehi and Daisuke Akai from the National Institute of Technology, Nagaoka College, and Masayuki Ushio from the Hakubi Center, Kyoto University (presently at the Hong Kong University of Science and Technology). "However, the electrical potential began to fluctuate after raining, sometimes going over 100 mV."

The researcher correlated this fluctuation with precipitation and temperature, and causality analysis revealed that the post-rain electric potential showed signal transport among mushrooms. This transport was particularly strong between spatially close mushrooms and demonstrated directionality.

"Our results confirm the need for further studies on fungal electrical potentials under a true ecological context," adds Fukasawa.

Details of their research were reported in the journal Fungal Ecology on March 14, 2023.

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JOURNAL

Fungal Ecology

DOI

10.1016/j.funeco.2023.101229