Tuesday, July 25, 2023

Cardiac rehabilitation reduces risk of death years after heart surgery, still underutilized

More targeted efforts are needed to improve participation, researchers say

MICHIGAN MEDICINE - UNIVERSITY OF MICHIGAN

For millions of Americans who have heart surgery or experience cardiovascular complications, like heart attack or heart failure, they may be encouraged to participate in cardiac rehabilitation. The medically supervised program combines lifestyle changes, education and physical activity to help patients recover and reduce their risk of future problems.

A Michigan Medicine study now finds that people who participate in cardiac rehabilitation have a decreased risk of death years after surgery, with a trend towards better outcomes in patients who attend more sessions.

“Time and time again, cardiac rehabilitation has been shown to improve outcomes and quality of life for patients undergoing heart surgery, yet we often fall short in getting patients to attend,” senior author Michael P. Thompson, Ph.D., assistant professor of cardiac surgery at University of Michigan Medical School.

Researchers explored over 6,400 Medicare fee-for-service claims linked to clinical registry data to assess cardiac rehabilitation use by Michigan residents after coronary artery bypass grafting, a procedure commonly called heart bypass, between 2015 and late 2019. The surgery improves blood flow to the heart by connecting a healthy artery or vein from another part of the body to a portion of the coronary artery that is blocked.

The multicenter study concluded that patients who underwent cardiac rehabilitation after heart bypass surgery had a 3-5% absolute reduced mortality rate in the two years following the procedure. The greatest reduction in mortality was found in patients who completed 36 or more sessions, which is the recommended number for coronary artery bypass grafting patients.

“While attending any cardiac rehabilitation session was better than none at all, our data highlight that patients received a greater benefit when they attended more sessions,” Thompson said. “Focusing on both attendance and adherence to cardiac rehabilitation will benefit patients.”

The patients who tended to participate in cardiac rehab after coronary artery bypass grafting were older on average, discharged to their home more often than an extended care facility and spent less time in the hospital.

Just over half of patients attended a single session of cardiac rehabilitation, and only 12% of those patients completed all 36 sessions. This occurred despite health systems referring patients to the program 94% of the time.

“Our findings suggest that referral alone is not be sufficient to ensure participation, and quality improvement efforts targeted at improving participation are needed,” said first author Tyler M. Bauer, M.D., general surgery resident at U-M Health.

“The gap between cardiac rehabilitation referral and actual use needs to be closed in order to give every patient the best chance and living longer and healthier lives.”

After accounting for patient risk factors, only 5% of the variation in cardiac rehab use was attributable to the hospital at which a patient had a procedure.

In a 2022 study, Michigan Medicine researchers found that Black patients who underwent stenting or balloon angioplasty for clogged arteries were referred to cardiac rehabilitation at significantly lower rates than white patients. Women, minorities, older adults and those with additional medical conditions are all under-referred to cardiac rehab, according to the Centers for Disease Control and Prevention.

"Minority and underserved populations face many barriers to cardiac rehab, but improving referral, attendance, and adherence in these populations may be an effective strategy to mitigating longstanding disparities in cardiovascular outcomes,” Thompson said.

Additional authors include, Temililaoluwa Daramola, M.D., Alexandra I. Mansour, Gorav Ailawadi, M.D. Francis D. Pagani, M.D., Ph.D., and Donald S. Likosky, Ph.D., all of U-M Health, Jessica M. Yaser, of the Michigan Value Collaborative, Patricia Theurer, B.S.N., and Steven J. Keteyian, Ph.D., both of the Michigan Society of Thoracic and Cardiovascular Surgeons Quality Collaborative.

Thompson receives funding from Blue Cross Blue Shield of Michigan for his role as Co-Director of the Michigan Value Collaborative. This study was supported by a grant from the Agency for Healthcare Research and Quality (K01HS027830). Likosky reports a relationship with Agency for Healthcare Research and Quality that includes: funding grants. The opinions, beliefs, and viewpoints expressed by authors do not necessarily reflect those of AHRQ, NIH or the U.S. Department of Health and Human Services, BCBSM, or its employees.

Paper cited: “Cardiac Rehabilitation Reduces Two-Year Mortality After Coronary Artery Bypass Grafting,” The Annals of Thoracic Sugery. DOI: 0.1016/j.athoracsur.2023.05.044

DOI

10.1016/j.athoracsur.2923.05.044

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Cardiac Rehabilitation Reduces Two-Year Mortality After Coronary Artery Bypass Grafting

ARTICLE PUBLICATION DATE

29-Jun-2023

COI STATEMENT

Dual wavelengths of light effective against antibiotic-resistant bacterium

Scientists have combined two light wavelengths to deactivate a bacterium that is invulnerable to some of the world’s most widely used antibiotics, giving hope that the regime could be adapted as a potential disinfectant treatment.

Peer-Reviewed Publication

APPLIED MICROBIOLOGY INTERNATIONAL

Under the guidance of project leader Dr Gale Brightwell, scientists at New Zealand’s AgResearch demonstrated the novel antimicrobial efficiency of a combination of two light wavelengths against a ‘superbug’ known as antibiotic-resistant extended-spectrum beta-lactamase E. coli.

Antimicrobial resistance (AMR) is a major global threat of increasing concern to human and animal health, with 10M deaths due to AMR forecast to occur every year after 2050. There is now a critical need to develop safe and effective antimicrobial technologies that do not result in new and emerging resistance, corresponding author Amanda Gardner explained.

A combination of far UVC (222 nm) and blue Led (405 nm) light have been shown to be effective in the inactivation of a wide range of microorganisms while being much safer to use and handle as compared to traditional UVC at 254 nm, she said.

“The E. coli we chose for this investigation were extended-spectrum beta- lactamases producing E. coli (ESBL-Ec) as these bacteria produce enzymes that break down and destroy commonly used antibiotics, including penicillins and cephalosporins, making these drugs ineffective for treating infections,” she said.

“This intrinsic resistance means that there are fewer antibiotic options available to treat ESBL-producing Enterobacteriaceae infections. In many cases, even common infections such as urinary tract infections require more complex treatments. Instead of taking oral antibiotics at home, patients with these infections might require hospitalisation and intravenous (IV) carbapenem antibiotics.

“The coupling of far-UVC and blue Led light together increases the effectiveness of the two individual lights through the deployment of different mechanisms of microorganism inactivation. There is great potential for these two light wavelengths to be used together in many applications where safety to the end user is of most importance,” she said.

The team found that a combination of dual far-UVC and blue Led light could be used to disinfect both antibiotic resistant and antibiotic sensitive E. coli, offering a non-thermal technology that may not drive further antibiotic resistance.

However, if exposed to sub-lethal levels of dual and far-UVC light, the antibiotic resistant E. coli tested did exhibit light tolerance. One surprising finding was that this light tolerance was only exhibited by the antibiotic resistant E. coli and not the antibiotic sensitive E. coli that was also tested.

Gardner says further work is needed to understand whether the light tolerance is due to a genetic change, or some other mechanism.

“It is also important to investigate the development of light tolerance in other antimicrobial-resistant bacteria and to determine the minimum dose of far-UVC light that can create light tolerance as well as the potential of further resistance development to other things such as sanitizers, heat, and pH in bacteria for application purposes,” she said.

The study was reported in the paper ‘Light Tolerance of Extended Spectrum β-lactamase Producing Escherichia coli Strains After Repetitive Exposure to Far-UVC and Blue LED Light’, which is publishedn by the Journal of Applied Microbiology, an Applied Microbiology International publication.

To find out more about AMI’s journals, visit HERE.

Notes to editors

Applied Microbiology International (AMI) is the oldest microbiology society in the UK and with more than half of its membership outside the UK, is truly global, serving microbiologists based in universities, private industry and research institutes around the world.AMI provides funding to encourage research and broad participation at its events and to ensure diverse voices are around the table working together to solve the sustainability development goals it has chosen to support.
AMI publishes leading industry magazine, The Microbiologist, and in partnership with Wiley and Oxford University Press, publishes six internationally acclaimed journals. It gives a voice to applied microbiologists around the world, amplifying their collective influence and informing international, evidence-based, decision making.
Oxford University Press (OUP) is a department of the University of Oxford. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide. OUP is the world's largest university press with the widest global presence.
OUP publishes more than 500 academic and research journals covering a broad range of subject areas, two-thirds of which are published in collaboration with learned societies and other international organizations. It has been publishing journals for more than a century and, as the world’s largest university press, has more than 500 years of publishing expertise.

JOURNAL

Journal of Applied Microbiology

DOI

10.1093/jambio/lxad124

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Dual wavelengths of light effective against antibiotic-resistant bacterium

ARTICLE PUBLICATION DATE

19-Jul-2023

UCLA biobank study reveals disease risk, heath care use among LA’s diverse population

Better understanding of shared genetic ancestry could lead to more targeted treatments

Peer-Reviewed Publication

UNIVERSITY OF CALIFORNIA - LOS ANGELES HEALTH SCIENCES

A new study of UCLA Health’s large genetic biobank is giving researchers new insights into the disease risks faced by the region’s diverse communities and their access to health care. The effort, published in Nature Medicine, may prove useful in developing personalized medicine and treatment approaches to groups often overlooked by the medical system.

UCLA Health researchers identified 376 population clusters based on shared genetic ancestry by leveraging information from nearly 36,000 patients enrolled in the UCLA ATLAS Precision Health Biobank. The ATLAS biobank, one of the world’s most diverse genetic repositories, links de-identified electronic health records from consenting UCLA Health patients with information about their genetic makeup obtained from donated biological samples. Using a machine-learning algorithm, researchers were able to identify groups linked by common genetic ancestry, including some that aren’t commonly studied in medicine like Iranian Jews and Lebanese Christians.

Researchers found substantial differences in the rates of diagnoses, hospital utilization, and genetic disease among the clusters. The findings underscore the limitations of the health care system’s frequent reliance on broad self-reported race and ethnicity data to assess patients’ risk of developing disease, and the findings also support expanding genetic screening to more groups, the researchers said.

Notably, however, shared genetic ancestry is just one factor to consider when trying to understand a population’s disease risk. While people with shared genetic ancestry may share genetic risk for disease, they may also share an environment – including structural factors like discrimination – that could influence their disease risk and how they interact with the health care system.

“The combination of your genetic risk and your environmental risk are the two most important things in determining whether you get a disease. It’s best for your doctor to have the best understanding of exactly what populations you might be coming from in order to assess things like disease risk or the need for genetic testing,” said lead author Christa Caggiano, a PhD student in the lab of Noah Zaitlen, a professor of computational medicine and neurology at UCLA Health who is also the study’s corresponding author.

Included in the researchers’ findings:

There was a great amount of genetic diversity within Mexican and Central American patients, which was partly explained by individual patients having different indigenous groups as ancestors. Researchers identified several subclusters of Mexican patients, which correlated with geographic region of Mexico and Guatemala. Only the Guatemalan subcluster was associated with pregnancy complications, while the Central Mexican subcluster was more prone to nutritional deficiencies. The finding provides further evidence that the health system’s usual practice of grouping patients by Hispanic and Latino is overly broad.
Researchers also examined specific genetic mutations associated with diseases. While sickle cell disease is widely known to be associated with African ancestry, researchers also found genetic variants implicated in sickle cell disease and thalassemia, another genetic blood disorder, that were at higher frequencies in the Chinese ancestry cluster. Although previous research has indicated this cluster is at higher risk of such blood diseases, the new finding reinforces how this group may benefit from genetic screening that isn’t widely available.
Other findings revealed how communities across the region access care. For instance, researchers found higher rates of people of Iranian Jewish descent being diagnosed with adjustment disorder, a psychiatric disorder not commonly coded for in medical records. Digging deeper, the researchers found the diagnoses were connected with a single medical center, indicating how social forces strongly affect care.

The researchers also created a website, ibd.la, to allow people to search through the data themselves. Caggiano said the website could be of interest to a patient curious about disease risk in their ethnic group or for a researcher working with a specific community.

Other authors include Joel Mefford, Ella Petter, Alec Chiu, Defne Ercelen, Rosemary He, Daniel Tward, Kimberly C. Paul, Timothy S. Chang, Bogdan Pasaniuc, Eimear E. Kenny, Brunilda Balliu, Valerie A. Arboleda and Gillian Belbin, all of UCLA; Arya Boudaie, Ruhollah Shemirani, Jonathan A. Shortt and Christopher R. Gignoux.

C.C. was supported by NIH F31NS122538. C.C., N.Z., D.E., and E.P. were supported by NIH grants R01CA227237, R01ES029929, R01MH122688, U01HG009080, R01HL155024, R01HL151152. R01GM142112 and R01HG006399. C.R.G. is supported by NIH grants R01HL151152 and R01HG010297. JAS and CRG are supported by NIH grant U01HG011715. N.Z., E.K., C.G., V.A., G.B. were supported by NIH grant R01HG011345. A.C. was supported by NIH grant T32HG002536 and NSF DGE-1829071. V.A. was supported by NIH grant DP5OD024579.

JOURNAL

Nature Medicine

DOI

10.1038/s41591-023-02425-1

ARTICLE TITLE

Disease risk and healthcare utilization among ancestrally diverse groups in the Los Angeles region

ARTICLE PUBLICATION DATE

18-Jul-2023

COI STATEMENT

CRG owns stock in 23andMe, Inc. EEK has received personal fees from Regeneron Pharmaceuticals, 23&Me, Allelica, and Illumina; has received research funding from Allelica; and serves on the advisory boards for Encompass Biosciences, Overtone, and Galateo Bio. All other authors declare no competing interests.

Patient transfer systems needed to ensure equity, as ICUs overload during pandemic

Peer-Reviewed Publication

WEILL CORNELL MEDICINE

In the study, published July 5 in Health Affairs, more than half of the regions studied experienced a load imbalance. “The research highlights the need for better coordination of patient transfers, which can alleviate overcapacity and ease inequities in care,” said senior study author Dr. William L. Schpero, assistant professor of population health sciences at Weill Cornell Medicine.

This study appears to be the first to closely examine the prevalence of hospital load imbalance during the pandemic and the type of hospitals that were affected, according to lead study author Dr. Adam S. Vohra, an interventional cardiology fellow in the Department of Medicine at Weill Cornell Medicine.

For their study, the researchers assessed data from 290 hospital referral regions (HRRs), which are geographic areas that designate hospital markets. Data on hospital capacity came from the COVID-19 Reported Patient Impact and Hospital Capacity files, produced by the U.S. Department of Health and Human Services.

The research team found that 154 HRRs, or 53.1 percent, experienced load imbalance during the study period, from July 31, 2020, through March 4, 2022. Regions with the most load imbalance had a higher proportion of residents who identified as Black. Moreover, hospitals with the highest proportion of Medicaid patients and Black Medicare patients were significantly more likely to be overloaded while other area hospitals had available capacity.

“We think we used a fairly conservative estimate of an imbalance, so if anything, we may be underestimating its prevalence,” Dr. Schpero said.

Some of the overburdened hospitals likely did not have enough staff, beds or supplies to safely meet patient needs, Dr. Schpero said. “Those resources did exist elsewhere, but many states have historically not had the infrastructure needed to address capacity constraints across hospitals and to reallocate patients accordingly,” he added.

Arizona, Minnesota and Washington, for example, have centralized coordinating hubs to manage transfer requests among hospitals during periods of high surge to help relieve the burden on overwhelmed hospitals. Most of these systems rely on critical care or emergency department nurses and technicians to facilitate patient transfers. “While we haven't followed up on the causal effect these coordinating hubs have on outcomes, in theory, these are the kind of the systems that could help,” Dr. Vohra said.

Moving patients from one hospital to another can be quite difficult, and transfer systems require timely data on patient need and bed availability across hospitals. Reporting mechanisms that only update weekly are too slow, Dr. Schpero said. “There needs to be a preexisting agreement across hospitals, either voluntarily or as a function of state law, to share real-time data on hospital capacity and facilitate transfers to ease strain.”

Because the urgency of the pandemic has subsided, “now is the time to take stock and invest in policies and practices that capitalize on lessons learned,” Dr. Schpero said. “Whether another pandemic arises, or a natural disaster occurs, we shouldn’t have to compromise on equitable patient care.”

JOURNAL

Health Affairs

ARTICLE TITLE

Many Intensive Care Units Were Overloaded While Nearby Hospitals Had Excess Capacity During The COVID-19 Pandemic

Could early induction of labor reduce inequities in pregnancy outcomes?

New study analyzed data on more than half a million births in England to probe the effects of inducing labor at 39 weeks gestation

Peer-Reviewed Publication

PLOS

Inducing labor at 39 weeks of pregnancy has the greatest benefit in risk reduction for women from more socioeconomically deprived areas, according to a new study published July 13th in the open access journal PLOS Medicine by Ipek Gurol-Urganci of the London School of Hygiene & Tropical Medicine, UK, and colleagues. The findings suggest that increased uptake of induction of labor at 39 weeks may help reduce inequities in adverse perinatal outcomes.

Adverse perinatal outcomes— which include stillbirths, neonatal deaths, preterm births, and other birth complications— are more common amongst women from deprived areas and ethnic minorities in England. There is ongoing debate about whether induction of labor with birth at 39 weeks should be offered in low-risk pregnancies based on ethnicity or socioeconomic status.

In the new study, researchers analyzed a database of all maternal admissions in the English National Health Service between January 2018 and March 2021. 501,072 women with low-risk pregnancies who had not yet given birth at 39 weeks were included in the analysis; of these, 47,352 (9.5%) had induction of labor at 39 weeks.

3.3% of births in the induction group and 3.6% of births in the expectant management group had an adverse perinatal outcome. After adjustment, researchers found a small benefit from induction of labor in low-risk pregnancies, with 360 inductions associated with the avoidance of one adverse outcome. However, the benefits of induction were mainly seen in women from more socioeconomically deprived areas (p=0.01) and women with no previous pregnancies (p=0.02).

“Improved collection of routine data on the indication for induction and the presence of risk factors is required to corroborate the role that induction of labor at 39 weeks in women with a low-risk pregnancy can play in reducing inequalities in risk of adverse perinatal outcomes,” coauthor Prof. Asma Khalil says.

Dr. Ipek Gurol-Urganci adds, "We used routinely collected administrative hospital data. Our study highlighted that we urgently need detailed, accurate and complete data from each maternity unit, collected at national level, especially about the indications of induction of labour, so that we get an even better understanding of the role that induction of labour can play in improving perinatal outcomes."

#####

In your coverage, please use this URL to provide access to the freely available paper in PLOS Medicine: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1004259

Citation: Muller P, Karia AM, Webster K, Carroll F, Dunn G, Frémeaux A, et al. (2023) Induction of labour at 39 weeks and adverse outcomes in low-risk pregnancies according to ethnicity, socioeconomic deprivation, and parity: A national cohort study in England. PLoS Med 20(7): e1004259. https://doi.org/10.1371/journal.pmed.1004259

Author Countries: United Kingdom

Funding: see manuscript

JOURNAL

PLoS Medicine

DOI

10.1371/journal.pmed.1004259

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

Immune systems develop ‘silver bullet’ defences against common bacteria

Peer-Reviewed Publication

UNIVERSITY OF EXETER

The host immune system is uniquely adapted to common environmental microbes — IMAGE: FRUIT FLY EXPERIMENTS SHOW THE HOST IMMUNE SYSTEM IS UNIQUELY ADAPTED TO COMMON ENVIRONMENTAL MICROBES. view more
CREDIT: DIEGO GALAGOVSKY

Immune systems develop specific genes to combat common bacteria such as those found in food, new research shows.

Previous theories have suggested that antimicrobial peptides – a kind of natural antibiotics – have a general role in killing a range of bacteria.

However, the new study, published in Science, examined how the immune systems of fruit flies are shaped by the bacteria in their food and environment.

The researchers, from the Swiss Federal Institute of Technology and the University of Exeter, found two peptides that each control a single bacterial species commonly encountered by the flies.

“We know that an animal’s food and environment determine the bacteria it encounters,” said Dr Mark Hanson, from the Centre for Ecology and Conservation on Exeter’s Penryn Campus in Cornwall.

“This in turn shapes its ‘microbiome’ – the collection of microbes that live in and on its body – and our study shows how immune systems evolve in response to this, to control common bacteria that could otherwise cause harm.

“In immune terms, it proves the saying ‘you are what you eat’ – the flies’ immune systems contain peptides with remarkably specific functions for controlling common bacteria.”

One such bacterium – Acetobacter, found in the fruits that flies eat (and in fruits humans eat) – can harm flies if it escapes the gut and reaches the bloodstream.

But the study shows various fly species have a specific peptide (Diptericin B) to control Acetobacter.

“This peptide is the silver bullet that kills this specific bacterium,” Dr Hanson explained.

“Without it, flies are extremely vulnerable because Acetobacter is so common in rotten fruit.”

The study also finds evidence of “convergent evolution” – when separate species evolve similar responses to challenges in their environment.

In this case, fly species in the study diverged from a common ancestor about 100 million years ago, yet they both evolved a Diptericin B peptide to control Acetobacter.

Meanwhile, closely related fly species that do not feed on fruit have lost their Diptericin B peptides over time, because Acetobacter is no longer common in their environment.

Dr Hanson said this evolutionary process might help to explain human susceptibility to certain infections.

“The way our bodies fight infections is really complex. But this sort of research helps us to view our immune system in a new light,” he said.

“I hope it gets us to ask why our immune system is made the way it is. That can help us fight infections, including infections that resist antibiotics.

“Studies like this produce fundamental observations about life, and in turn these can have crucial applications in the world around us.”

The research was funded by the Swiss National Science Foundation and Novartis Foundation.

The paper is entitled: “Ecology-relevant bacteria drive the evolution of host antimicrobial peptides in Drosophila.”

JOURNAL

Science

DOI

10.1126/science.adg5725

ARTICLE TITLE

Ecology-relevant bacteria drive the evolution of host antimicrobial peptides in Drosophila

ARTICLE PUBLICATION DATE

20-Jul-2023

These bones were made for walking

Peer-Reviewed Publication

COLUMBIA UNIVERSITY IRVING MEDICAL CENTER

NEW YORK, NY--Perhaps the most profound advance in primate evolution occurred about 6 million years ago when our ancestors started walking on two legs. The gradual shift to bipedal locomotion is thought to have made primates more adaptable to diverse environments and freed their hands to make use of tools, which in turn accelerated cognitive development. With those changes, the stage was set for modern humans.

The genetic changes that made possible the transition from knuckle-based scampering in great apes to upright walking in humans have now been uncovered in a new study by researchers at Columbia University and the University of Texas.

Using a combination of deep learning (a form of artificial intelligence) and genome-wide association studies, the researchers have created the first map of the genomic regions responsible for skeletal changes in primates that led to upright walking. The map reveals that genes that underlie the anatomical transitions observed in the fossil record were strongly acted on by natural selection and gave early humans an evolutionary advantage.

“On a more practical level, we’ve also identified genetic variants and skeletal features that are associated with hip, knee, and back arthritis, the leading causes of adult disability in the United States,” says Tarjinder Singh, PhD, assistant professor of computational and statistical genomics (in psychiatry) at the Columbia University Vagelos College of Physicians and Surgeons and a co-leader of the study.

For example, slight deviations from the average hip width-to-height ratio were associated with an increased risk of hip osteoarthritis, while slight deviations in the tibia-femur angle were associated with an increased risk of knee osteoarthritis. These insights could help researchers devise new ways to prevent and treat these debilitating conditions.

The findings were published July 21 in Science. The study was co-led by Vagheesh M. Narasimhan, PhD, assistant professor of integrative biology and of statistics and data sciences at the University of Texas at Austin.

New techniques deployed

The researchers applied deep learning to analyze more than 30,000 full-body X-rays from the UK Biobank. Deep learning, a technology modeled after the brain’s neural networks, trains computers to do what comes naturally to humans, such as driving a car or translating languages. In this case, the technique was used to standardize the X-rays, remove any images with quality issues, and then precisely measure dozens of skeletal features, tasks that would have taken the researchers months, if not years, to complete.

Next, the researchers scanned the human genome to identify chromosomal regions associated with variations in 23 key skeletal measures, such as shoulder width, torso length, and tibia-to-femur angle. (These scans, called genome-wide association studies, involve surveying the genomes of large groups of people, looking for genomic variants that occur more frequently in those with a specific disease or trait compared to those without the disease or trait.) This process revealed 145 regions associated with genes that regulate skeletal development. Only a handful of these loci were known from previous studies.

Many of the 145 regions overlapped with “accelerated” regions of the human genome, which have rapidly evolved over eons compared with the same regions in great apes. In contrast, few genes associated with the heart, immune system, metabolism, and other traits were found in accelerated regions.

“What we’re seeing is the first genomic evidence that there was selective pressure on genetic variants that affect skeletal proportions, enabling a transition from knuckle-based walking to bipedalism,” says Narasimhan.

The study also shows the power of combining large-scale biobank data, machine learning, and genomics to help us understand human health and disease. Singh, who joined Columbia in 2022, is now applying these techniques to understand the causes of mental illness.

More information

Tarjinder Singh, PhD, is also an associate member of the New York Genome Center.

The paper is titled “The genetic architecture and evolution of the human skeletal form.”

The other contributors are Eucharist Kun (University of Texas at Austin), Emily M. Javan (Texas), Olivia Smith (Texas), Faris Gulamali (Icahn School of Medicine at Mount Sinai, New York), Javier de la Fuente (Texas), Brianna I. Flynn (Texas), Kushal Vajrala (Texas), Zoe Trutner (Texas), Prakash Jayakumar (Texas), Elliot M. Tucker-Drob (Texas), and Mashaal Sohail (Universidad Nacional Autónoma de México, Cuernavaca).

The study was supported by the Allen Discovery Center program and a Good Systems for Ethical AI grant from the University of Texas at Austin.

The authors declare no competing interests.

###

Columbia University Irving Medical Center (CUIMC) is a clinical, research, and educational campus located in New York City. Founded in 1928, CUIMC was one of the first academic medical centers established in the United States of America. CUIMC is home to four professional colleges and schools that provide global leadership in scientific research, health and medical education, and patient care including the Vagelos College of Physicians and Surgeons, the Mailman School of Public Health, the College of Dental Medicine, the School of Nursing. For more information, please visit cuimc.columbia.edu.

JOURNAL

Science

METHOD OF RESEARCH

Imaging analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

The genetic architecture and evolution of the human skeletal form

ARTICLE PUBLICATION DATE

21-Jul-2023

Living together: Microbial communities are more than the sum of their parts

Peer-Reviewed Publication

DELFT UNIVERSITY OF TECHNOLOGY

Bacterial colonies from microbial communities — IMAGE: IMAGES OF 24 BACTERIAL COLONIES FROM THE STUDIED MICROBIAL COMMUNITIES. view more
CREDIT: DJORDJE BAJIC

Microbial communities are widely used biotechnology suppliers for processes like manufacturing biofuels and new foods, or helping crops grow better. To engineer successful communities, scientists need to predict whether microorganisms can live and work together. One popular predictive rule states that if a pair of microbes will coexist, they will also coexist in a bigger community of microbes. A study published in Science now found that this simple rule will not always work.

Just like plants and animals, microorganisms live in complex ecological communities consisting of multiple species that coexist with one another. These communities are found all over the planet, and they also play a growing and highly promising role in biotechnology. Microbial communities are being designed for producing biofuels and other essential products in biorefineries, to create new foods, or to help crops grow better. Thus, learning how to engineer these communities to improve the services they provide is a major goal in biotechnology.

One of the major roadblocks for engineering microbial communities is that not all microorganisms will coexist with one another. Even if we manage to design a microbial community with high potential, it is very likely that many of its members will go extinct. This is why scientists are trying to find ways to predict whether species will coexist with one another.

“We are trying to understand the stunning diversity that we see in bacterial communities. How can that many species manage to coexist within the same community?” - Djordje Bajić, Assistant Professor in Industrial Microbiology / Delft University of Technology

A simple rule

Researchers from University of Pennsylvania, Centro Nacional de Biotecnología of the Spanish National Research Council, Delft University of Technology and Yale University studied how to predict bacterial coexistence in complex communities. In this paper by Chang et al, the authors have examined a popular hypothesis: That in order for multiple species (say A, B and C) to coexist as a community, every pair of species must also coexist with one another as an isolated pair, e.g. A must coexist with B, B must coexist with C, and C must coexist with A. This hypothesis has been gaining ground over the past few years, and it is very enticing because, if it were generally correct, it offers a simple and practical way to predict coexistence in complex microbial communities.

To test this hypothesis, the authors decided to take apart twelve different microbial communities containing between three and ten species coexisting together. They then competed every possible pair of microorganisms, and found that contrary to the above hypothesis, most pairs failed to coexist. In other words, the simple rule to predict coexistence will not always work, indicating that when it comes to coexistence, the whole is often more than the sum of its parts.

New predictive tools

Chang’s paper emphasizes that the important problem of predicting which microbes can live together is not yet solved, highlighting the need to build new predictive tools. Although this may be seen as bad news, it actually represents a huge leap forward by establishing that in microbial communities, the whole is much more than the sum of its parts. This will help us build new models that can ultimately help us engineer microbial communities.

“We are trying to understand the stunning diversity that we see in bacterial communities”, says Djordje Bajić, Assistant Professor in Industrial Microbiology. “How can that many species manage to coexist within the same community?” Understanding how bacteria coexist is important for a better understanding of our world, since microbial communities colonise almost every surface on our planet, Bajić explains: “They play roles in global element cycling and are essential for the health of our own gut microbiome. This study will definitely have an impact on our understanding of microbial communities and the microbiome. And it will also inform the building of models and technologies to design microbiomes and steer existing ones towards desired states in many applications: for example in health, wastewater treatment, production of sustainable biopesticides and biofertilisers based on microbes.”

The party of the bacteria
You can think about this study as if you are at a party, where you like many people, but you don’t like many other people. The established idea is that you need to like everyone at the party in order to have a good time. This does not have to be the case, of course. You may just ignore the individuals you don’t like, and choose to spend your night talking to other people. You may even participate in discussions with people you are less fond off, and still have a good time, as long as other people are also in these conversations.

JOURNAL

Science

DOI

10.1126/science.adg0727

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Cells

ARTICLE TITLE

Emergent coexistence in multispecies microbial communities

ARTICLE PUBLICATION DATE

21-Jul-2023

Sending the shoes back? How about this lovely gift card? Cross-selling can help retailers avoid lost revenue from returns

Peer-Reviewed Publication

UNIVERSITY OF TORONTO, ROTMAN SCHOOL OF MANAGEMENT

https://www.rotman.utoronto.ca/Connect/MediaCentre/NewsReleases/20230720

Toronto - It’s become so darn easy to order stuff thanks to the miracles of online shopping. But it’s not so simple on the retailer end, especially when more than 16 per cent of those sales are later sent back. In the U.S., that adds up to a staggering $816 billion in lost revenue.

Cross-selling can help, say a pair of researchers. Their experiments show that once we’ve chosen to buy something, we tend to consider that money as already spent or gone, also called “loss booking.” If we decide we want to return the item, retailers can take advantage of that tendency by giving customers enticing options to spend their refund on something else, instead of getting their money back.

In a nutshell, “it hurts less to spend money refunded from a product return than other money, because you feel like you’ve already lost it,” says researcher Chang-Yuan Lee, an assistant professor of marketing at the University of Toronto’s Rotman School of Management.

Prof. Lee and his colleague Carey K. Morewedge from Boston University showed this over and over again in a series of experiments. Participants were more likely to buy an item when they were paying for it through refund money compared to funds they hadn’t already spent. This occurred even in cases of unexpected money – it was still easier to apply a refund to another item than to spend windfall funds on it, such as imagined lottery winnings or tax refunds. And study participants were willing to accept an item outside their original product category – a $100 gift card for a sports shoe company after the return of a $90 grocery item.

There’s a catch though. The shopper has to psychologically mark the initial spend as lost, something that does not happen when they expect to ask for a refund at the time of purchase. Study participants who bought two pairs of shoes in different sizes, expecting to return the poorer-fitting pair, were not so likely to turn around and immediately apply the refund to something else offered.

Retailers are already on to cross-selling’s value. The researchers cite the online exchanges-first platform Loop Returns which claims to have retained nearly 29 per cent of potentially lost sales revenue for online merchants by offering consumers alternative product options before initiating a refund.

While consumers could be discouraged from making returns by being charged extra fees, that leaves a bad taste in their mouth and previous research has shown they may take their business elsewhere.

“Our proposed cross-selling strategy offers a solution for retailers to minimize revenue loss without imposing significant costs on both the retailers and consumers,” says Prof. Lee.

The study appears in the July issue of the Journal of Consumer Psychology.

Bringing together high-impact faculty research and thought leadership on one searchable platform, the new Rotman Insights Hub offers articles, podcasts, opinions, books and videos representing the latest in management thinking and providing insights into the key issues facing business and society. Visit www.rotman.utoronto.ca/insightshub.

The Rotman School of Management is part of the University of Toronto, a global centre of research and teaching excellence at the heart of Canada’s commercial capital. Rotman is a catalyst for transformative learning, insights and public engagement, bringing together diverse views and initiatives around a defining purpose: to create value for business and society. For more information, visit www.rotman.utoronto.ca

-30-

JOURNAL

Journal of Consumer Psychology

DOI

10.1002/jcpy.1354

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Mental accounting of product returns