Category Archives: Physiology

‘Walking Sharks’ Are a Thing, But Don’t Worry – They’re Adorable – ScienceAlert

In an epic 12-year research effort, an international team of scientists has discovered four species of 'walking sharks', almost doubling the known species count of these rare and gifted animals.

While the image of a shark chasing you onto a sandy beach may now be firmly planted in your mind, that's not how the physiology of these animals works and there's nothing to fear from these species found in tropical waters between northern Australia and New Guinea (unless you're a tiny marine animal, that is).

"At less than a metre [3.3 ft] long on average, walking sharks present no threat to people,"says biologist Christine Dudgeonfrom the University of Queensland in Australia.

"But their ability to withstand low-oxygen environments and walk on their fins gives them a remarkable edge over their prey of small crustaceans and molluscs."

The four new shark species belong to the genus Hemiscyllium. The new members of the group were linked to five existing kinds of shark through genetic analyses, using tissue samples from live-caught specimens found during the study.

"We estimated the connection between the species based on comparisons between their mitochondrial DNA which is passed down through the maternal lineage," Dudgeon says.

"This DNA codes for the mitochondria, which are the parts of cells that transform oxygen and nutrients from food into energy for cells."

The results confirmed the new animals' DNA was consistent with existing Hemiscyllium species, which can be traced back to the Late Cretaceous period, extending from roughly 66 to 100 million years ago.

Given the immense time scales involved, and the broad scope of international waters, it can be difficult to know exactly how these walking shark species came to be, and why they evolved their separate adaptations.

"It can be challenging to identify the forces that drive speciation in marine environments for organisms that are capable of widespread dispersal because their contemporary distributions often belie the historical processes that were responsible for their initial diversification," the authors explain in their paper.

Nonetheless, we can speculate. In this instance, the researchers suggest Hemiscyllium may have effectively hitch-hiked around the place while geographical shifts emerged over aeons, as tectonic activity and sea-level changes shifted the positions of reefs and island chains.

"Data suggests the new species evolved after the sharks moved away from their original population, became genetically isolated in new areas and developed into new species," Dudgeon says.

"They may have moved by swimming or walking on their fins, but it's also possible they 'hitched' a ride on reefs moving westward across the top of New Guinea, about 2 million years ago."

The team says more walking shark species are likely to exist, too it's just a matter of finding them.

The findings are reported in Marine and Freshwater Research.

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'Walking Sharks' Are a Thing, But Don't Worry - They're Adorable - ScienceAlert

Our bodies are chronically in "threat mode" – being kind recalibrates our nervous system – Big Think

Kindness is a virtue that is admired and applauded, in most cases. But did you know that being kind can also be good for your health? In fact, being compassionate to others can actually reset our consistently stressed-systems back into our default "rest mode", causing all kinds of positive effects to our overall health.

Living in "threat mode" isn't healthy for our minds or our bodies.

Image by Pogorelova Olga on Shutterstock

According to Dr. James Doty, Stanford professor and author of Into the Magic Shop: A Neurosurgeon's Quest to Discover the Mysteries of the Brain and Secrets of the Heart, the nervous system was never made to be in threat mode all the time. And yet, our adrenaline-fueled, "on-the-go" lifestyles have us operating mainly in "threat mode", and this can actually be one of the reasons we contract a variety of different illnesses.

Our bodies release inflammatory proteins in response to stress. Because of this release, our nervous system shows a decrease in the capabilities of our immune system, which is what responds to threats such as germs or bacteria that cause illnesses.

The constant over-stimulation of our nervous systems caused by our fast-paced way of living also makes us much more inclined to jump to (often judgmental) conclusions about other people.This kind of quick judgment actually dulls our own ability to act out of compassion for others. Which, in turn, leaves us operating in a constant "threat mode", which has negative long-term effects on our health.

The ability to feel and act out of compassion for others can have a huge effect on your overall health.

Dr. Doty explains it best in this Uplift article:

"When someone acts with compassionate intentions, this has a huge, huge positive effect on their physiology. It takes them out of threat mode and puts them into the rest and digest mode. What happens when that occurs is it changes how they respond to events."

According to Dr. Doty, instead of a quick response that is often based on fear, anxiety or stress, our response time is slower and offers a more deliberate response that tends to be more effective, more creative and more compassionate. We are able to change the response we have to events because we are allowing the executive control area of our brain to function at the highest level.

Several studies at Emory University have demonstrated this and given results that support the idea that regular compassionate acts or compassion-based meditation practices can reduce negative neuroendocrine interactions in our brains (which are the interactions between our nervous system and the endocrine system).

The benefits from being kind can help us live healthier, happier lives.

Photo by ESB Professional on Shutterstock

When we switch to our parasympathetic nervous system (which we instinctively do, when we act out of compassion), we flip out of the sympathetic nervous system that most of us live in due to our busy lifestyles.

When this switch happens, our heart rate variability increases, which causes a boost in our immune system. This immune system boost can help us fight off infections or illnesses.

Now, let's talk about telomeres.

"Telomeres" likely isn't a word you've heard before, so let me give a quick definition of what they are to us.

Telomeres are like little caps that protect the ends of chromosomes and genetic information in our bodies during cell division. Essentially, telomeres get shorter each time a cell copies itself (which happens constantly).

Eventually, telomeres get too short to do their job of protecting the cells, and this causes the cells to age and eventually stop functioning properly. This is how telomeres essentially act as an aging clock in every cell we have.

Research by Dr. Doty has shown that one of the long-term positive effects of living in our parasympathetic nervous system (referred to as our "resting" mode) is that our telomeres actually increase in length.

In theory, over time, being kind and compassionate can actually slow down the aging process in some of the cells of our body. How crazy is that!?

Just as showing compassion can recalibrate our systems, experiencing compassion or kindness from others also has a positive impact on our systems. Research by a Stony Brook University professor (Stephanie Brown) has proven that experiencing compassion can lead to tremendous improvements in our mental and physical well-being, as well.

This ground-breaking research allow us to understand the benefits that kind human interactions can have on the health of our minds and bodies.

The positive ripple effect that comes from being kind doesn't just impact our health, but it can impact our interactions with others and set off a positive chain reaction we can't even begin to understand. Resetting your own system into its natural resting mode by taking ourselves out of threat mode can allow us to process things more clearly and make better choices.

In a world where you can be pretty much anything - be kind...it's good for your health.

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Our bodies are chronically in "threat mode" - being kind recalibrates our nervous system - Big Think

High Blood Pressure Differs In Women From Men – American Council on Science and Health

In effect, the broadening clinical experience of managing CVD conditions that manifest differently between women and men, combined with the accumulating data on sex-specific CVD presentations, suggest that cardiovascular pathophysiology is likely to be fundamentally different between the sexes.

The Study

Researchers made use of 4 community cohort studies on cardiovascular disease providing 144,599 blood pressure measurements from 32,833 individuals (54% women) over a 43 year period spanning the ages 5 to 98.

The graph on the left demonstrates something we have known for a long time, that the onset of hypertension in men occurs earlier than in women. The graph on the right takes those snapshots and calculates the trend and this is what is new. It is not so much that women catch up with men as that their blood pressure elevations accelerate (the slope) in their late 30s.

When the researchers adjusted for the usual suspect risk factors, i.e., diabetes, cholesterol, BMI, and smoking the effect was the same, although slightly attenuated.

This difference in trajectory held true for both the systolic and diastolic blood pressures as well as two calculated values, the pulse pressure which is, in turn, a rough measure of stiffening of the arterial wall; and mean arterial pressure, a rough measure of the thickness of the arterial wall. So conclusion, women have a different physiologic pathway than men.

During the time course of the study, almost 30%of men and 20% of women had hard cardiovascular events, a fatal or non-fatal heart attack, stroke, or heart failure. So other protective or deleterious factors are involved beyond high blood pressure in cardiovascular disease.

What could those factors be?

The most obvious candidates for differences lie in the hormonal milieu and in the differences in the size of the involved organs in women versus men. But there is no clear cut evidence in that regard. The other possibilities lie in the realm of our culture and its effect on gender.

Importantly, complex social, economic, and structural environmental factors lead to differences in the lived experience between women and men that can also affect physiology as well as vascular biology.

In the end, we do not know. What we do know with increasing evidence is that in the same way children are not small adults, women are not just child-bearing men. While ourcommonalities may far outweigh our differences, it may well be our differences that set the stage for the expression of disease.

Source: Sex Differences In Blood Pressure Trajectories Over the Life Course JAMA Cardiology DOI: 10.1001/jamacardio.2019.5306

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High Blood Pressure Differs In Women From Men - American Council on Science and Health

Effects of Wearing Compression Stockings on Exercise Performance and A | OAJSM – Dove Medical Press

Gustavo R Mota,1 Mrio Antnio de Moura Simim,2 Izabela Aparecida dos Santos,1 Jeffer Eidi Sasaki,1 Moacir Marocolo3

1Human Performance and Sport Research Group, Department of Sport Sciences, Institute of Health Sciences, Federal University of Triangulo Mineiro, Uberaba, MG, Brazil; 2Research Group in Biodynamic Human Movement, Institute of Physical Education and Sports, Federal University of Cear, Fortaleza, CE, Brazil; 3Physiology and Human Performance Research Group, Department of Physiology, Federal University of Juiz de Fora, Juiz de Fora, MG, Brazil

Correspondence: Gustavo R MotaHuman Performance and Sport Research Group, Department of Sport Sciences/Institute of Health Sciences, Federal University of Tringulo Mineiro, Av. Tutunas, 490 Uberaba/MG, Uberaba 38061-500, BrazilTel +55 34 3700-6633Email grmotta@gmail.com

Abstract: This systematic review investigated the effects of wearing below-knee compression stockings (CS) on exercise performance (or sports activity) and associated physiological and perceived indicators. We searched articles on PubMed using the following terms: graduated compression stockings; compression stockings; graduated compression socks; compression socks combined with performance, athletes, exercise, exercise performance, fatigue, sports and recovery, resulting in 1067 papers. After checking for inclusion criteria (e.g., original studies, healthy subjects, performance analysis), 21 studies were selected and analyzed. We conclude that wearing CS during exercise improved performance in a small number of studies. However, wearing CS could benefit muscle function indicators and perceived muscle soreness during the recovery period. Future research should investigate the chronic effect of CS on Sports Medicine and athletic performance.

Keywords: ergogenic aid, fatigue, sports, medicine, prevention, soccer, running

This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License.By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

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Effects of Wearing Compression Stockings on Exercise Performance and A | OAJSM - Dove Medical Press

Irregularity in eating schedules during weekend linked to obesity – News-Medical.net

A new study by the University of Barcelona (UB) concluded that irregularity in eating schedules during the weekend, named by the authors as eating jet lag, could be related to the increase of body mass index (BMI), a formula that measures weight and height to determine whether someone's weight is healthy.

These results, published in the science journal Nutrients, were independently taken from factors such as the quality of the diet, level of physical activity, social jet lag (difference in sleeping schedules during weekends) and chronotype (natural predisposition to a certain sleeping schedule).

According to the researchers, this is the first study that shows the importance of regularity in eating schedules -including weekends- to control weight, and could be an element to consider as part of nutrition guidelines to prevent obesity.

The study, jointly led by Maria Izquierdo Pulido, from the Department of Nutrition, Food Sciences and Gastronomy of the UB and INSA-UB, and Trinitat Cambras, from the Department of Biochemistry and Physiology of the UB, is part of the doctoral thesis of the researcher Mara Fernanda Zern Rugerio, first author of the article. Other participants in the article are lvaro Hernez, from the August Pi i Sunyer Biomedical Research Institute (IDIBAPS) and the Physiopathology of Obesity and Nutrition Networking Biomedical Research Centre (CIBERobn), and Armida Patricia Porras Loaiza, from Universidad de las Amricas Puebla (Mexico).

During the last years researches proved the body understands calories differently depending on the time of the day. Eating late can be related to a higher risk of obesity. According to Maria Izquierdo Pulido, "this difference is related to our biological clock, which organizes our body to understand and metabolize calories consumed during the day". At night, however, "it gets the body ready for fasting while we sleep".

"As a result -the researcher continues-, when intake takes place regularly, the circadian clock ensures that the body's metabolic pathways act to assimilate nutrients. However, when food is taken at an unusual hour, nutrients can act on the molecular machinery of peripheral clocks (outside the brain), altering the schedule and thus, modifying the body's metabolic functions".

The new study was carried out on a population of 1,106 young people (aged between eighteen and twenty-two) in Spain and Mexico. Researchers analyzed the relation between the body mass index and the variability in eating timing during weekends compared to the rest of the days. To do so, authors used a new marker that gathers changes in eating times (breakfast, lunch and dinner) at weekends: the eating jet lag, presented for the first time in this study.

Our results show changing the timing of the three meals during the weekend is linked to obesity. The highest impact on the BDI could occur when there is a 3.5-hour difference in eating schedules. After this, the risk of obesity could increase, since we saw individuals who showed a 3.5-hour eating jet lag increased their BDI in 1.3. kg/m2.

Mara Fernanda Zern Rugerio, first author of the article

To explain the link between eating jet lag and obesity, authors suggest individuals to undergo a chronodisruption, that is, a lack of synchrony between internal time of the body and social time. "Our biological clock is like a machine, and is ready to unchain the same physiological and metabolic response at the same time of the day, every day of the week. Fixed eating and sleep schedules help the body to be organized and promote energy homeostasis. Therefore, people with a higher alteration of their schedules have a higher risk of obesity", notes Cambras.

More research is needed to reveal the physiological mechanisms and metabolic alterations behind the eating jet lag and its link to obesity. However, authors highlight the importance of keeping regular eating and sleeping schedules to preserve health and wellbeing. "Apart from diet and physical exercise, which are two pillars regarding obesity, other factor to be considered is regular eating schedules, since we proved it has an impact on our body weight", notes Izquierdo Pulido.

The study notes the importance of doing research on the relation between time irregularity and the evolution of weight over time, as well as conducting the study on populations with different social and economic characteristics, metabolic features and different age. "Variability in eating schedules during weekends compared to week days can happen chronically during someone's life. Future studies should evaluate the effect of this chronic variability through the eating jet lag, on the evolution of weight", conclude researchers.

Source:

Journal reference:

Zern-Rugerio, M. F. et al. (2019) Eating Jet Lag: A Marker of the Variability in Meal Timing and Its Association with Body Mass Index. Nutrients. doi.org/10.3390/nu11122980

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Irregularity in eating schedules during weekend linked to obesity - News-Medical.net

There’s A New Key To Avoiding The Freshman 15 | The University Network – The University Network

Want to avoid the freshman 15? The key may be keeping a regular eating schedule, as new research suggests eating meals later on the weekends than during the week could lead to weight gain.

Nutritionists and health nuts have long known that when it comes to keeping off extra weight, when you eat can matter as much as what you eat. Eating all of your food between 6 a.m. and 7 p.m., for example, is a proven way to shed and keep off pounds, as bodies understand calories differently depending on what time it is.

What hadnt been explored, until this study, was whether disruptions to the regularity of meal time like swapping breakfast for brunch could also lead to weight gain.

During the week, people generally have a routine. And as a result, they may eat their meals at roughly the same times each day. On weekends, however, days are typically less structured and people tend to wake up and go to bed later, which often postpones and irregulates the times they eat their meals. The researchers refer to this habit as eating jet lag.

To conduct their study, the researchers surveyed more than 1,100 college students in Spain and Mexico to find what time they were eating their meals on weekends compared to weekdays.

While nearly two-thirds of the students showed more than one hour of eating jet lag on the weekends, the ones most at risk of gaining weight were those who waited more than 3.5 hours to eat their meals.

In essence, the longer the students postponed their weekend meals, the more at-risk they were of packing on the pounds. According to the researchers, the results werent related to what the students ate, how much they exercised or any specific sleeping habits, and were independent of age, nationality and gender.

Our results show changing the timing of the three meals during the weekend is linked to obesity. The highest impact on the BMI (Body Mass Index) could occur when there is a 3.5-hour difference in eating schedules, Mara Fernanda Zern Rugerio, a co-author of the study from the University of Barcelona (UB), said in a news release.

The researchers explained that the reason people may gain weight when eating outside of their normal schedule is because they are disrupting their biological clocks. For example, if someones body is used to eating meals at 8 a.m., 12 p.m. and 6 p.m. each day, thats when it will prepare itself to effectively metabolize that food.

Our biological clock is like a machine, and is ready to unchain the same physiological and metabolic response at the same time of the day, every day of the week. Fixed eating and sleep schedules help the body to be organized and promote energy homeostasis. Therefore, people with a higher alteration of their schedules have a higher risk of obesity, Trinitat Cambras, a lead author of the study from UBs Department of Biochemistry and Physiology, said in the news release.

Though, when it comes to staying trim, fit and healthy, the researchers noted that maintaining regular eating habits is just one piece to the puzzle, with the other key components being diet and exercise.

They also noted that more research is needed to investigate the impact of irregular eating on weight fluctuation over time.

Variability in eating schedules during weekends compared to week days can happen chronically during someones life, the researchers concluded. Future studies should evaluate the effect of this chronic variability through the eating jet lag, on the evolution of weight.

News & Content Manager

Jackson Schroeder is a graduate of Ohio University with a B.A. in Journalism from the E.W. Scripps School. He is originally from Savannah, Georgia. Jackson has covered a wide range of topics, including sustainability, technology, sports, culture, travel, and music. He plays bass and guitar, and enjoys playing and listening to live music in his free time.

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There's A New Key To Avoiding The Freshman 15 | The University Network - The University Network

Physiology & Breeding Collection Review, 2020 – ResearchAndMarkets.com – Business Wire

DUBLIN--(BUSINESS WIRE)--The "Physiology & Breeding Collection" company profile has been added to ResearchAndMarkets.com's offering.

This is a new thematic database of chapters bring you comprehensive reviews of the latest research in crop science as 'bite sized' pieces of content and will enable you to efficiently access what's really going on in your specialist subject. This collection includes 218 chapters that review advances in crop and livestock physiology and genetics. It also includes chapters on advances in crop and livestock breeding techniques and their application in improving crop varieties and livestock breeds.

For more information about this company profile visit https://www.researchandmarkets.com/r/rtsnv7

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Physiology & Breeding Collection Review, 2020 - ResearchAndMarkets.com - Business Wire

Male and Female Physiology – The Good Men Project

Cultures are built on natures construction of male and female physiology.

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ANSWER

True. Humans efforts to survive and succeed in their environments create cultural formulae consciously and unconsciously. This has resulted in the creation of social classes and undergirds prevalent teachings and practices on how to think, behave and speak as masculine or feminine individuals.

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The Manhood Game cards were created and developed by Dr. George Simons as a way to reframe mens perceptions of themselves.

As Dr. Simons writes in his intro post:

Life is often played as a game in which mens welfare is a pawn to be sacrificed. Today I invite you to join me in another game, diversophy Manhood, a game for reframing mens perceptions of themselves, for refreshing their mission in life, and disarming social biases that attack male health and limit the possible in their own eyes and actions. Each day I will post a new card from this game, a snippet of wisdom to GUIDE our exploration, a RISK to face, facts to test our SMARTS, a CHOICE to make, or an experience to SHARE.

We are always looking for people to write about the changing roles of men in the 21st century. The Manhood Game Cards make great writing prompts. What is your view on how mens roles are changing? Can you write a post (300-750 words) that tells us your own unique point of view? If so, please join our writers community and click here to submit via our submissions portal.

The Good Men Project has pioneered the largest worldwide conversation about the changing roles of men in the 21st century. Your support of our work is inspiring and invaluable.

All Premium Members get to view The Good Men Project with NO ADS.

A $50 annual membership gives you an all-access pass. You can be a part of every call, group, class, and all our online communities.A $25 annual membership gives you access to one class, one Social Interest group and our online communities.A $12 annual membership gives you access to our Friday calls with the publisher and our online community.

Need more info? A complete list of benefits is here.

This post was previously published on http://www.linkedin.com and is republished here with permission from the author.Photo credit: iStock

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Male and Female Physiology - The Good Men Project

Women Have Steeper, Earlier BP Increases Over Lifetime – Medscape

New findings from an analysis of sex-specific blood pressure trajectories show that starting at an early age and continuing throughout life, women experience steeper increases in blood pressure than men.

"In contrast with the notion that important vascular diseases in women lag behind men by 10 to 20 years, our findings indicate that certain vascular changes not only develop earlier but also progress faster in women than in men," the authors state.

"In effect, sex differences in physiology, starting in early life, may well set the stage for later-life cardiac as well as vascular diseases that often present differently in women compared with men," they suggest.

The study was published online in JAMA Cardiology on January 15.

The findings could have implications regarding different strategies for managing high blood pressure in women compared to men, senior author Susan Cheng, MD, told Medscape Medical News.

Cheng is director of cardiovascular population sciences and public health research at the Barbra Streisand Women's Heart Center and the Smidt Heart Institute at Cedars-Sinai Medical Center, Los Angeles, California.

"If a clinician sees two patients of the same age and similarly elevated blood pressure, but one male and one female, before this paper, we would think they should receive the same kind of intervention. But now we know that in order for the woman to have reached a level of 140, her BP has risen earlier and faster than is the case for the man," she commented.

The current data show that women start out with systolic pressure of about 105 mmHg, whereas men start out at about 115 mmHg, she noted. "We believe women's blood pressure is supposed to be slightly lower than men's throughout life, so when we see a level of 140 mmHg in a woman, that may indicate a higher risk than that conferred by the same pressure in a man," Cheng explained.

"I would say that of these two patients, the woman is likely to be at higher risk of blood-pressure-related outcomes than the man," she added.

Cheng said this had not been recognized before because women tend to present with cardiovascular disease in different ways than men. "They are more likely to have small-vessel disease rather than a large atherosclerotic plaque in a major coronary artery, and small-vessel disease is more likely to go undetected," she said.

"I would say that in the scenario of a man and woman with similar levels of raised blood pressure, clinicians need to pay more attention to the woman. But actually, what tends to happen is the opposite. There is a perception that women are not at such high cardiovascular risk as men, and raised blood pressure is often dismissed as anxiety in women," she said.

Cheng noted that it has typically been thought that women start out better than men because of the protective effect of estrogen, and when this wears off at the time of menopause, women's blood pressure levels and cardiovascular risk catchup with those of men.

"But our data do not suggest that this is the case. We did not see any spike of blood pressure in women at menopause rather, a smooth, continuous rise of levels throughout life, which starts earlier and accelerates faster than in men."

Cheng suggested that different thresholds for definitions of increased blood pressure and hypertension may be needed for men and women. "We need to think about what is normal and abnormal for men and for women separately and what this means for thresholds and treatments," she stated.

In their article, the researchers note that during the past 2 decades, mounting evidence has highlighted differences between women and men in the manifestation of common cardiovascular diseases. It is now increasingly recognized that women are more likely than men to develop coronary microvascular dysfunction and heart failure with preserved ejection fraction, especially in conjunction with vascular risk factors such as hypertension.

These observations suggest that cardiovascular pathophysiology is likely to be fundamentally different between the sexes, they say.

To look into this further and noting that measures of blood pressure represent the single most accessible metric of vascular aging and that increased blood pressure is the largest contributor to cardiovascular risk the researchers used population-based multicohort data to conduct a comprehensive sex-specific analysis of blood pressure trajectories over the life course.

They analyzed data collected over a period of 43 years in four community-based US cohort studies that included a total of 32,833 participants (54% women).

Results showed that compared with men, women exhibited a steeper increase in blood pressure that began as early as the third decade and continued through the life course. After adjustment for multiple cardiovascular disease risk factors, these between-sex differences in all blood pressure trajectories persisted.

"We believe that steeper elevation represents something important about baseline differences in physiology that contributes to differences in the pathophysiology of cardiovascular disease in men and women," Cheng said.

"I think we're coming to understand that there are sex differences in cardiovascular risks that start much earlier than the hormonal changes associated with menopause probably even at birth or prebirth," she added.

Additional work is needed "to further understand sexual dimorphism in cardiovascular risk to optimize prevention and management efforts in both women and men," the authors conclude.

In an accompanying editorial, Nanette K. Wenger, MD, Emory University School of Medicine, Atlanta, Georgia, says these new findings introduce "the concept that biology serves as an underpinning of sex differences in the pathophysiology of cardiovascular illnesses, in subsequent distinct pathophysiologic alterations, and in the variability in treatment effectiveness."

In an audio interview with JAMA Cardiology, Wenger stated: "Hypertension is not just the numbers of the blood pressure. It is probably the most accessible measure of vascular aging and that starts quite early. This gives us a window on the biologic changes, and certainly many of them involve the endothelium."

She pointed out that hypertension has more adverse physiologic consequences for women than for men. "Women get more left ventricular hypertrophy, more concentric hypertrophy. Women treated for elevated blood pressure do not have as much regression of their left ventricular hypotrophy as do men, and they have more left atrial enlargement. Women with hypertension lose their gender-specific protection against coronary disease."

But Wenger also noted that, "sadly," women are less likely to be treated to target than men. "We see across the spectrum of care that women receive less preventative therapies, fewer diagnostic tests, less likely to receive guideline-recommended medical therapies because they are perceived not to be vulnerable to cardiovascular disease.

"I would hope that many of our colleagues will become involved in examining sex and gender differences, because there are so many influences of this on how we diagnose and treat women and men," she concluded.

The study was funded by grants from Gilead Sciences, the National Institutes of Health, the National Center for Research Resources, the National Center for Advancing Translational Sciences, the Edythe L. Broad and the Constance Austin Women's Heart Research Fellowships, the Barbra Streisand Women's Cardiovascular Research and Education Program, the Society for Women's Health Research, the Linda Joy Pollin Women's Heart Health Program, the Erika Glazer Women's Heart Health Project, and the Adelson Family Foundation. Cheng received grants from the National Institutes of Health during the conduct of the study and personal fees from Zogenix outside the submitted work. Wenger has disclosed no relevant financial relationships.

JAMA Cardiol. Published online January 15. Abstract, Editorial

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Women Have Steeper, Earlier BP Increases Over Lifetime - Medscape

Total-Body PET/CT Plus Innovative Image Reconstruction Yields Clear Cardiac Cycle Images – Diagnostic Imaging

A total-body PET/CT scanner paired with an advanced sub-second molecular image technique can enable real-time blood-flow tracking and motion-frozen imaging of cardiovascular and respiratory functions, according to newly published research.

The findings, supported by funding from the National Institutes of Health and University of California Davis Innovative Development Award, were published in the Jan. 20 edition of the Proceedings of the National Academy of Sciences.

Investigators, led by UC-Davis project scientist Xuezhu Zhang, developed a 194-cm long total-body EXPLORER scanner, a three-dimensional medical imaging device that covers the entire body at once, allowing for simultaneous dynamic imaging of multiple organs with significantly higher sensitivity. They combined the machine with an innovative image reconstruction method called kernel expectation maximization.

High temporal resolution PET is useful for studying blood flow, transit times, and fast radiotracer dynamics, Zhang wrote. It can also be used to freeze subject motion, either physiological, such as cardiac and respiratory motion, or involuntary body motion, thereby improving the effective spatial resolution of reconstructed images.

The cardiac and respiratory motion captured in these PET images can also provide information for evaluating the biomechanical properties of various organs, he said. Study findings indicate combining the scanner and the reconstruction method allows for good-quality dynamic PET images at 100-ms temporal resolution.

For the study, researchers intravenously injected 256 MBq of 18F-fluorodeoxyglucose into the right leg of a healthy 60-year-old woman before conducting a 60-minute total-body dynamic scan. They divided the first-minute data into 100-ms temporal frames and analyzed reconstructed images in order to demonstrate the high temporal resolution of this method for capturing fast tracer dynamics and real-time cardiac motion.

Reconstructed dynamic PET image analysis revealed good image quality even though there were fewer than 1 million true coincident events in each temporal frame. The 100-ms dynamic PET images identified cardiac blood pool changes effectively throughout the cardiac cycle with a clear delineation of the end-systolic and end-diastolic phases. The images also clearly showed the flow of the radiotracer with each contraction of the heart.

In addition, investigators compared images of four regions of interest the left ventricle, ascending aorta, descending aorta, and myocardium gathered by both a standard whole-body scanner and dynamic PET imaging. Results indicated dynamic PET imaging provided better results.

Existing imaging systems, including angiography, CT, MRI, and ultrasound, can offer fast imaging and specific anatomical information, but none offer real-time molecular imaging of physiology and biochemistry with total-body coverage, Zhang said.

Ultimately, this imaging technique could offer improved imaging in other areas, as well.

This high-temporal resolution tracer imaging technique opens up the opportunity for new applications, such as studying fast pharmacodynamics, using shorter-lived radionuclides, and performing motion-frozen scans of the heart, lung, and gastrointestinal tract, he wrote.

Additionally, he said, PET with high temporal resolution has potential applications in pinpointing normal and abnormal brain functions by directly measuring the absolute value of cerebral blood flow and cerebral metabolic rate of oxygen.

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Total-Body PET/CT Plus Innovative Image Reconstruction Yields Clear Cardiac Cycle Images - Diagnostic Imaging