Publisher Health

Scientists have redesigned a key component of a widely used CRISPR-based gene-editing tool, called Cas9, to be thousands of times less likely to target the wrong stretch of DNA while remaining just as efficient as the original version, making it potentially much safer.
One of the grand challenges with using CRISPR-based gene editing on humans is that the molecular machinery sometimes makes changes to the wrong section of a host’s genome, creating the possibility that an attempt to repair a genetic mutation in one spot in the genome could accidentally create a dangerous new mutation in another.
But now, scientists at The University of Texas at Austin have redesigned a key component of a widely used CRISPR-based gene-editing tool, called Cas9, to be thousands of times less likely to target the wrong stretch of DNA while remaining just as efficient as the original version, making it potentially much safer. The work is described in a paper published today in the journal Nature.
“This really could be a game changer in terms of a wider application of the CRISPR Cas systems in gene editing,” said Kenneth Johnson, a professor of molecular biosciences and co-senior author of the study with David Taylor, an assistant professor of molecular biosciences. The paper’s co-first authors are postdoctoral fellows Jack Bravo and Mu-Sen Liu.
Other labs have redesigned Cas9 to reduce off-target interactions, but so far, all these versions improve accuracy by sacrificing speed. SuperFi-Cas9, as this new version has been dubbed, is 4,000 times less likely to cut off-target sites but just as fast as naturally occurring Cas9. Bravo says you can think of the different lab-generated versions of Cas9 as different models of self-driving cars. Most models are really safe, but they have a top speed of 10 miles per hour.
“They’re safer than the naturally occurring Cas9, but it comes at a big cost: They’re going extremely slowly,” said Bravo. “SuperFi-Cas9 is like a self-driving car that has been engineered to be extremely safe, but it can still go at full speed.”
So far, the researchers have demonstrated the use of SuperFi-Cas9 on DNA in test tubes. They’re now collaborating with other researchers who plan to test SuperFi-Cas9 for gene editing in living cells. They’re also working to develop still safer and more active versions of Cas9.

As of today, there is no vaccine against hepatitis C. To improve the search for it, researchers are looking for a so-called surrogate model: an animal that can also suffer from viral hepatitis and whose course of infection allows conclusions about the behavior of the hepatitis C virus in humans. They found what they were looking for in the horse.
Virus escapes the immune system
More than 70 million people worldwide are infected with hepatitis C. The disease is treatable, but it is often not recognised. In 80 per cent of cases, it takes chronic courses and can lead to liver damage and even liver cancer. So far, there is no effective vaccine. “The reason why the disease often doesn’t clear up is that the virus is constantly changing and thus escapes the immune system,” explains Dr. Daniel Todt from the RUB Virology Department. “The immune system forms antibodies that always lag behind the virus for a while and have the ability to combat a variant that was in the body about two weeks before.” This evolution of the virus within the host is therefore of particular interest to the researchers.
To date, there have been no suitable models to deal with these questions in animal experiments. In their quest for a so-called surrogate model for research into the human hepatitis C virus, the scientists analysed samples from horses that were taken in cooperation with the University of Veterinary Medicine Hannover (TiHo). “If you compare hepatitis viruses that can infect different species, it is striking that the human virus and the virus that is infectious for horses are genetically close relatives,” explains André Gömer, PhD student at the TiHo Research Training Group VIPER and lead author of the paper. The researchers analysed the surface proteins of viruses from humans and horses in the course of infection and compared the results.
A better understanding of the virus’ tactics
“In the horse virus, a region that we call hypervariable is missing,” explains Gömer. It changes particularly quickly and protects an area of the virus that helps it infect host cells. This could be one reason why the infection in horses, unlike in humans, is rarely chronic. “These findings help us to better understand the tactics of the hepatitis C virus and to find out which areas of the virus are the most relevant,” says Todt. The equine hepatitis virus infection of horses could represent a powerful model to gain insights into hepaciviral evolution and hepatitis C virus immune evasion.
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Materials provided by Ruhr-University Bochum. Original written by Meike Drießen. Note: Content may be edited for style and length.

Impressive athleticism was on display during the Winter Olympics, but being at the top of one’s game doesn’t necessarily protect against digestive distress resulting from exercise. Surprisingly, some people are adding cocoa to their diets to reduce these symptoms. Now, researchers in ACS’ Journal of Agricultural and Food Chemistry report that long-term daily consumption of cocoa doesn’t appear to improve exercise-related digestive issues in male athletes and induces only minimal changes to their gut microbiomes.
Performing vigorous or intense exercise can cause digestive upset for some people. The symptoms can include nausea, heartburn, abdominal cramps and diarrhea. In the worst cases, symptoms are so bad that athletes stop what they’re doing and drop out of competitions. Previous studies have suggested that long-term cocoa consumption could alleviate these issues because of the tasty substance’s high level of flavonoids. These compounds can enhance antioxidant and anti-inflammatory activity and have been shown to have prebiotic effects on beneficial gut microbes in animal studies. However, chronic consumption of cocoa powder by humans to reduce exercise-related digestive problems hasn’t been investigated in a standardized way. So, François Fenaille, Mar Larrosa, and colleagues wanted to develop a highly controlled but also realistic human trial to assess whether cocoa could help.
Using the gold standard format for human trials, the researchers conducted a randomized, placebo-controlled study of 54 physically fit male athletes who followed a strict training routine over 10 weeks. During that time, participants supplemented their regular diets with either flavonoid-rich cocoa or a placebo starch powder mixed into semi-skim milk, which they drank daily at breakfast. At the beginning and the end of the training period, the athletes underwent a high-endurance running test. The participants’ gastrointestinal symptoms did not change in either supplementation group, indicating the cocoa did not improve exercise-induced digestive complaints. Finally, the researchers found only slight effects on the composition of the gut microbiome and plasma and fecal metabolites. Although the athletes’ diets, which included a high amount of fruits and vegetables, could have masked a small effect of the cocoa, the researchers conclude that cocoa is not an effective exercise supplement for suppressing gastrointestinal problems or changing the overall gut microbiome of endurance athletes.
The authors acknowledge funding from the Ministry of Economy, Industry and Competitiveness (Spain); European Molecular Biology Organization; Ministry of Education, Culture and Sports (Spain); and MetaboHUB infrastructure (France).
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Early in the pandemic, many people fastidiously disinfected surfaces because laboratory studies predicted that SARS-CoV-2 could be easily transmitted in this way. Now, researchers reporting in ACS Central Science have found a possible explanation for why the predictions didn’t pan out: Sugar-decorated proteins in mucus could bind to the coronavirus on surfaces, keeping it from infecting cells. The findings could also hint at why some people are more vulnerable to COVID-19 than others.
Although experiments have shown that coronaviruses can persist on surfaces for days or weeks, it is now apparent that SARS-CoV-2 is much more likely to infect people through airborne droplets carrying the virus. The surface studies typically used viruses suspended in buffers or growth media, whereas in the real world, SARS-CoV-2 is coated in mucus when someone coughs or sneezes. With this in mind, Jessica Kramer and colleagues wondered if mucus components could explain the discrepancy between the lab predictions and reality. In addition to water, salts, lipids, DNA and other proteins, mucus contains proteins called mucins, which are heavily modified with sugar molecules known as glycans. To infect cells, the SARS-CoV-2 spike protein binds glycan molecules with sialic acid at their ends on the cell surface. So, the researchers wondered if the coronavirus also recognizes sialic acid-containing glycans in mucins. If the spike protein is already bound to glycans in mucus, perhaps it couldn’t bind to the ones on cells, they reasoned.
For safety reasons, the researchers chose to study a human coronavirus called OC43, which evolved relatively recently from a cow coronavirus and causes mostly mild respiratory infections. The team deposited droplets of the virus in buffer or growth medium supplemented with 0.1-5% mucins, which corresponds to the concentration range of mucins found in nasal mucus and saliva, onto a plastic surface and let the drops dry. Then, they rehydrated the viral residue and measured its ability to infect cells. In comparison to the buffer or growth medium alone, the solutions supplemented with mucins were dramatically less infectious. The team also tested steel, glass and surgical mask surfaces, finding similar results.
The researchers showed that, as the droplets dried, mucins moved to the edge and concentrated there in a coffee-ring effect, bringing the virus with them. This brought mucins and virus particles close together, where they could more easily interact. Cutting off sialic acid glycans from mucins with an enzyme eliminated viral binding and destroyed the glycoproteins’ protective effect. Because SARS-CoV-2, like OC43, binds to sialic acid glycans on cell surfaces, mucins would also likely reduce its infectivity, the researchers suspect. The levels and types of sugar molecules on mucins can vary with diet and certain diseases, which could possibly explain the vulnerability of certain people to COVID-19, they say.
The authors acknowledge funding from the National Science Foundation.
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Marcel Dicke already knew that insects are an excellent source of protein for humans, but he didn’t expect to learn that they have such a positive impact on plants. In an Opinion paper published on March 2 in the journal Trends in Plant Science, Dicke, a researcher at Wageningen University in the Netherlands, and colleagues discuss the benefits of using the waste from insect-as-food-and-feed production to promote sustainable crops. The authors argue this approach could enhance plant growth, health, pollination, and resilience.
The leftovers from insect production come in two main forms: exuviae, the exoskeletons left behind after molting, and frass, named for the German word for eating. Frass is “basically insect poop and unconsumed food,” says Dicke.
When added to soil, the exuviae and frass promote both plant growth and health. Insect feces are rich in nitrogen, a nutrient that is pivotal to plant growth but is scarce in most soils; therefore, it is often added to crops in synthetic fertilizer. The insect exoskeletons are rich in chitin, a polymer that is difficult for most organisms to digest.
“There is, however, a set of bacteria that can metabolize chitin, and those microbes help plants to be more resilient to diseases and pests,” says Dicke. “When exuviae are added to soil, the populations of those beneficial bacteria increase.”
Dicke and his team see the application of insect-rearing byproducts to crops as a novel step towards a circular food system in which there is very little waste. The insects are fed waste streams from crop farming or food production, and the insects then provide humans with food. Using the leftovers from insect production to bolster crop growth could close this circle. Now, he just needs to get people on board.
Insects, which Dicke refers to as “mini-livestock,” are already efficient to farm, especially when compared to more traditional livestock. It takes roughly 25 kilograms of grass to produce one kilogram of beef. The same amount of grass can produce ten times as much edible insect protein. This is due to the higher conversion rate of insects and because up to 90% of an insect’s body mass is edible, as opposed to only 40% of a cow.
“I have eaten crickets, mealworms, and locusts,” says Dicke. “Many people in in our part of the world need to get used to eating insects, but I can tell you that I’ve eaten many other insect species around the globe, and I’ve always had a wonderful meal on them.”
The researchers plan to continue to investigate the potential for exuviae to work as a pest control. When a plant is attacked by an insect, its leaves can produce volatiles that attract the predators of the pest. “I call it the plant’s cry for help,” says Dicke. “They are recruiting bodyguards.”
Dicke thinks that a similar process might be happening through the plants’ roots and that the microbes that are digesting the chitin in the insect waste might also be acting as security for the plants by breaking down pathogenic fungi and making the plant resilient to pests. “Studies have already shown that microbes associated with the roots help plants by protecting against diseases,” says Dicke. “Now we’re investigating whether plant roots recruit microbes that help them in defending against pests.”
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Transmission of respiratory viruses depends partly on the rate of close social contacts in a population. A study publishing March 1 in PLOS Medicine by Amy Gimma at the London School of Hygiene and Tropical Medicine, United Kingdom, and colleagues suggests that during the most restrictive period of lockdown in the United Kingdom, the number of reported contacts decreased by 75% from pre-pandemic levels.
Public health policies imposed during the COVID-19 pandemic aimed to curb virus transmission through reduced social contact. However, the impact of these policies over time has not been quantified. To estimate social interactions in England from March 2020-March 2021, researchers conducted a cross-sectional study of 19,914 participants aged 18-59, as well as parents completing the survey on behalf of their children under age 18, who voluntarily responded to online surveys about their demographics, behavior, and perceptions of personal risk with regard to the pandemic. They then used statistical analyses to calculate the average number of daily contacts reported by participants.
The researchers found that during the most restrictive lockdowns in the UK, adults over 17 years of age reduced the number of people they were in contact with by 75%. Throughout the year, during less stringent policies, people continued to reduce their social contacts, and only ever reached 50% of pre-pandemic levels. However, the study had some limitations; all data were self-reported, which may have contributed to over- or underestimating individuals’ number of contacts. In addition, future research is needed to apply these findings to transmission data from 2021-2022.
According to the authors, “We launched the CoMix social contact and behavioural study on 24th March 2020 to capture the changes in social contacts, risk perception, and other behaviours. This study quantifies changes in epidemiologically relevant contact behaviour for one full year of the COVID-19 pandemic in England and can be used to inform future outbreak response and can be applied to transmission of other infectious diseases, particularly for a large-scale pandemic.”
Gimma adds, “Social contacts play a key role in the transmission of respiratory viruses, such as COVID-19, and data from the CoMix survey helps researchers, policymakers, and the general public understand how people have changed their social contacts throughout the pandemic. Understanding how and where people are making the most contacts, such as at work or in educational settings, provides insight into where contacts can be reduced when we need to slow transmission.”
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Tinnitus, most often described as “ringing” in the ears even though no external sound is present, also can be perceived as humming, hissing, buzzing or roaring sounds. According to the United States Centers for Disease Control and Prevention (CDC), more than 50 million Americans experience some form of tinnitus — 2 million have extreme and debilitating cases. Worldwide, about 30 percent of people will experience tinnitus at some point in their life.
Many individuals impacted by COVID-19 experienced changes in their sense of smell, taste, hearing, balance and in some cases, tinnitus. Among the various causes of tinnitus is stress, including tension, anxiety and depression. What’s unclear, however, is whether the psychological impacts of the pandemic such as stress actually worsened tinnitus and its impacts.
Researchers from Florida Atlantic University, the Royal Surrey NHS Foundation Trust in the United Kingdom, and the University of Cambridge conducted a study that focused on the potential indirect effects of COVID-19 on the experience of tinnitus. They assessed whether the severity of tinnitus, as measured using ratings of tinnitus loudness, annoyance, and effect on life, was influenced by the lockdown related to pandemic. Although COVID-19 upended so many aspects of society, there is some good news — at least as it relates to tinnitus.
For the study, researchers compared two independent groups of new patients; one group assessed during three months of lockdown in the United Kingdom and one group assessed during the same period in the preceding year. They examined patients’ pure-tone audiometry, and their score on visual analog scale (VAS) of tinnitus loudness, annoyance, and effect on life, which were imported from their records. Researchers compared VAS ratings from both groups. All patients were seeking help for their tinnitus for the first time.
Results of the study, published in the Journal of the American Academy of Audiology, do not support the idea that the pandemic led to a worsening of tinnitus loudness, annoyance, or impact on life and the mean scores did not differ significantly for the groups seen prior to and during lockdown. Any changes in psychological well-being or stress produced by the lockdown did not significantly affect ratings of the severity of tinnitus.
“People experienced various types of adversities during the pandemic, including loss of income, difficulty in obtaining services, experience of the virus itself, and the impact of constant bad news and social distancing,” said Ali Danesh, Ph.D., co-author, professor, Department of Communication Sciences and Disorders/Communication Disorders Clinic within FAU’s College of Education, a member of FAU’s Stiles-Nicholson Brain Institute and FAU’s Institute for Human Health and Disease Intervention, professor of biomedical sciences, FAU Schmidt College of Medicine, and an affiliate faculty, Department of Psychology, FAU Charles E. Schmidt College of Science. “It’s possible that pandemic related factors exacerbate the experience of tinnitus, as tinnitus is linked to general anxiety and psychological well-being. On the other hand, perhaps the effect of COVID-19 on everyday life made individuals with tinnitus realize that there are more important things than tinnitus, putting it into perspective and leading to a decrease of the impact of tinnitus that counteracted any effect of increased anxiety and decreased well-being.”
Several studies on tinnitus reported sleep-related problems, poor mental health, and suicidal ideations as consequences of the COVID-19 pandemic and its associated social isolation and economic uncertainties.
“It is questionable whether people are able to judge reliably whether their tinnitus itself has changed or whether their tinnitus-related symptoms such as sleep disturbances or anxiety have changed,” said Hashir Aazh, Ph.D., affiliate associate professor at FAU and Honorary Hearing Research Consultant, Department of Audiology, Royal Surrey County Hospital. “Prior studies of the indirect effects of COVID-19 on the experience of tinnitus have used different methodologies, which may have led to biases.”
The current study avoided potential biases by comparing self-reported tinnitus severity between new patients seen during lockdown and another group of patients seen during the same time frame, preceding lockdown.
“If a given respondent felt that their tinnitus was worse during the pandemic than before the pandemic, how could they determine whether this was due to lifestyle changes, health concerns, or social distancing?,” said Danesh. “Visual analog scale scores for tinnitus loudness, annoyance, and impact on life did not differ significantly between new patients seen prior to and during lockdown. This may indicate that tinnitus can influence anxiety and well-being, but there is not an effect in the opposite direction.”
The retrospective study examined data for 105 consecutive patients who were seen at a tinnitus clinic in an audiology department in the United Kingdom during lockdown and 123 patients seen in the same period of the previous year. The average age of the patients seen during the lockdown was 50 years, while the average age of the patients seen in 2019 was 56 years. The two groups were reasonably well matched in age, gender, and severity of hearing loss.
Study co-author is Brian C. Moore, Ph.D., emeritus professor of auditory perception, Department of Experimental Psychology, University of Cambridge.

The molecular evolution of placental protein NRK and its function in regulating placental growth has finally been clarified by researchers from Tokyo Tech. They elucidated that eutherian NRK regulates placental development by a novel mechanism, modulating the CK2-PTEN-AKT pathway. They also determined that this new function was acquired due to the amazingly rapid molecular evolution of NRK in eutherian ancestors.
Viviparity is a reproductive strategy in which the mother provides the embryo with a continuous supply of nutrients in her body to grow sufficiently before giving birth. Compared with oviparity, it can increase the survival rate of fetuses and newborns. The mammalian placenta is a representative tissue for supplying nutrients to the fetus and is evolutionarily novel. NIK-related kinase (NRK) is a key protein discovered to play an important role in placental development. Previous research showed that mouse NRK is specifically expressed in the placenta, and “knocking out” this protein resulted in placental hyperplasia and difficult delivery. However, the specifics on how this was achieved were unclear.
This is soon to be an issue of the past, with a team of researchers from Tokyo Institute of Technology(Tokyo Tech) in Japan, publishing a study in Molecular Biology and Evolution, elucidating the evolutionary factors and molecular mechanisms involved in the observed functions of NRK. Elucidating these issues behind NRK function is of great importance, according to the author Assistant Professor Toshiaki Fukushima, who says, “It will not only lead to understanding some of the mechanisms of placental evolution but provide a basis for developing diagnostic and therapeutic methods for pregnancy complications, including fetal growth retardation.”
To understand the evolutionary patterns involved, the team carried out synteny and phylogenetic studies on the Nrk gene in different species as it was detected across vertebrates. Interestingly, the Nrk gene sequence of eutherians was found to significantly differ from other groups, and phylogenetic analysis showed that NRK protein underwent rapid molecular evolution including amino acid insertions/substitutions in the process of evolving into eutherians at an unparalleled rate.
These evolutionary patterns gave insight into the molecular mechanisms of NRK function in eutherians. Previous studies had already confirmed that the ability to impede cell proliferation was restricted only to this form of NRK, with other members of the family proteins lacking this suppressive function. On closer examination of the protein structure, scientists were able to identify specific regions of interest. One such section identified was situated in the middle region of this protein, spanning from amino acid 565-868. Functional assays revealed that it was bound to casein kinase-2 (CK2), an inactivator of PTEN, which is a regulator of the AKT signaling pathway. Another important region identified was the citron homology domain located at the end of the protein. Through fluorescent imaging, it was discovered that this domain is crucial for the localization of NRK to the plasma membrane.
Based on the subsequent experiments, this research team revealed detailed molecular mechanism of NRK function. This protein is localized to the plasma membrane by means of the citron homology domain, where the middle region binds to CK2, thus preventing it from phosphorylating PTEN. This activated PTEN downregulates phosphatidylinositol (3,4,5)-trisphosphate, an important driving factor of AKT signaling. Reduced AKT signaling leads to attenuation of cell proliferation. CK2, PTEN, and AKT have been reported to regulate placental growth, respectively, and now it has been revealed that the placenta-specific protein NRK regulates this pathway as an upstream factor.
Importantly, the functional regions in NRK were gained in the process of evolving into eutherians. This study is the first to suggest that placental protein NRK is now control of cell proliferation signaling by getting functional sequences in the eutherian ancestors. As the author concludes, “NRK evolution facilitated the proper control of placental development in placenta mammals.” This research opens up new avenues for investigating molecular evolutions for mammals to acquire the unique developmental tissue, the placenta.
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A team of researchers at Tohoku University have developed a simple lab-based system for growing human muscle cells that are capable of vigorously contracting. The team used the model, which was described in the journal Scientific Reports, to investigate the properties of muscle cells from patients with sporadic inclusion body mitosis (sIBM).
sIBM is a degenerative disease that causes muscles to get progressively weaker. It typically affects patients aged over 50, predominantly impacting muscles in the fingers and knees. Observing how muscle cells from sIBM patients work during exercise is crucial to understanding more about this disease.
This can be achieved using ‘in vitro exercise models,’ which involve growing elongated muscle cells called myotubes in a petri dish and applying electrical pulses to them to simulate the effects of muscle contraction. However, these widely used models are limited; the human myotubes do not contract very well because they are flat in shape and attach firmly to the material they are grown on. In comparison, myotubes obtained from other species, such as mice, contract much more strongly under the same conditions.
“We set out to develop a new model that could help not only basic muscle research, but also the diagnostic use of muscle cells obtained from patient biopsy samples, which are a very limited resource,” said Dr. Makoto Kanzaki, Associate Professor at the Graduate School of Biomedical Engineering, Tohoku University.
To aid the growth of human myotubes, the researchers used muscle cells taken from a mouse cell line to create a population of nourishing connective tissues. The mouse cells, known as ‘feeder cells,’ supply essential proteins to encourage the growth of the human cells. They used this method to nurture human myotubes grown from muscle stem cells obtained from sIBM patients.
They found that without the mouse feeder cells, the human myotubes showed very little contraction in response to electrical stimulation. However, once the mouse cells were added, the human myotubes showed obvious contraction-related activity when electrically stimulated.
The researchers used several different imaging techniques to examine the properties of the muscle cells from sIBM patients and to compare them with those from healthy humans. They found that sIBM myotubes have basically the same muscular properties as normal myotubes. Both contracted vigorously upon electrical stimulation, showed the development of muscle fibre structures called sarcomeres and had raised levels of a skeletal muscle protein called myokine.
However, they found that myotubes from sIBM patients had raised levels of a protein called TDP-43 after contraction, while healthy muscle cells did not. This suggests that TDP-43 may be involved in the disease.
“The use of feeder cells expands the usefulness of existing lab-based exercise models, and our system could potentially be used to evaluate the effects of exercise on patient muscle cells,” explains Dr. Kanzaki.
This muscle cell model may help to improve our understanding of muscle cell conditions, particularly in response to muscle contractions. This could provide important diagnostic information to aid the development of customized therapies.
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Some oral bacteria were associated with the development of hypertension, also known as high blood pressure, in postmenopausal women, according to new research published today in the Journal of the American Heart Association, an open access, peer-reviewed journal of the American Heart Association.
High blood pressure is typically defined by two measurements: systolic blood pressure (the upper number measuring pressure when the heart beats) of 130 mm Hg or higher, and diastolic blood pressure (the lower number indicating pressure between heart beats) of 80 mm Hg or higher.
While previous research has indicated that blood pressure tends to be higher in people with existing periodontal disease compared to those without it, researchers believe that this study is the first to prospectively examine the association between oral bacteria and developing hypertension.
“Since periodontal disease and hypertension are especially prevalent in older adults, if a relationship between the oral bacteria and hypertension risk could be established, there may be an opportunity to enhance hypertension prevention through increased, targeted oral care,” said Michael J. LaMonte, Ph.D., M.P.H., one of the study’s senior authors, a research professor in epidemiology at the University at Buffalo — State University of New York and a co-investigator in the Women’s Health Initiative clinical center in the University’s epidemiology and environmental health department.
Researchers evaluated data for 1,215 postmenopausal women (average age of 63 years old at study enrollment, between 1997 and 2001) in the Buffalo Osteoporosis and Periodontal Disease Study in Buffalo, New York. At study enrollment, researchers recorded blood pressure and collected oral plaque from below the gum line, “which is where some bacteria keep the gum and tooth structures healthy, and others cause gum and periodontal disease,” LaMonte said. They also noted medication use and medical and lifestyle histories to assess if there is a link between oral bacteria and hypertension in older women.
At study enrollment, about 35% (429) of the study participants had normal blood pressure: readings below 120/80 mm Hg, with no use of blood pressure medication. Nearly 24% (306) of participants had elevated blood pressure: readings above 120/80 mm Hg with no medication use. About 40% (480) of participants were categorized as having prevalent treated hypertension: diagnosed and treated for hypertension with medication.