Category Archives: Physiology

Physiology

The Big 3: Why phthalates should be restricted or banned from consumer products – HSPH News

March 10, 2021 Russ Hauser, Frederick Lee Hisaw Professor of Reproductive Physiology and professor of environmental and occupational epidemiology, discusses a recent paper he co-authored with colleagues from Project TENDR (Targeting Environmental Neuro-Development Risks) that outlines the health dangers of chemicals called ortho-phthalates and calls for their elimination in consumer products.

Q: What are ortho-phthalates and where are they used?

A: These chemicalsgenerally referred to as phthalatesare a family of compounds that has been widely used for well over 50 years. They have many properties that make them useful in many different consumer products. One of their common uses is to soften vinyl plastic. Things like shower curtains, boots, and IV tubing are made from that same hard white plastic that a plumber would use, but when you add about 30% by weight to it of a specific phthalate, you get soft pliable vinyl plastic. Phthalates are also used in many personal care products such as colognes, perfumes, soaps, and shampoos, in the coatings of some medications, and in vinyl tubing used for food processing. I would estimate that phthalates are used in many hundreds if not thousands of different products.

One primary way that people can be exposed to phthalates is through diet. For example, its been shown that these chemicals can leach into food from vinyl plastic equipment and materials, food preparation gloves, and food packaging materials. Phthalates can also migrate into indoor air and household dust from products like vinyl flooring and wall coverings. Numerous studies have found links between personal care product use and concentrations of phthalate metabolites in urine. And phthalates are transferred from mother to fetus during pregnancy.

Q: Can you describe some of the health impacts of these chemicals?

A: Phthalates have been very well studied in animal models. Theyve been shown to be anti-androgenicin other words, they decrease testosterone. In studies with rats, its been shown that if you dose the pregnant mother, the offspring have defects of the male reproductive tract. There have also been studies in humans that have found anti-androgenic effects on development of the male reproductive tract.

In the last ten years, epidemiologic studies have also shown that prenatal exposure to phthalates affects childrens neurodevelopmental and neurobehavioral outcomes. That was the focus of the new paper, which reviewed more than a dozen studies that have shown that maternal exposure to ortho-phthalates during pregnancy can impair child brain development and increase childrens risks for learning, attention, and behavioral disorders.

Q: What has been done so far in the U.S. to reduce the use of ortho-phthalates, and what more should be done?

A: In 2017, the Consumer Product Safety Commission banned the use of eight ortho-phthalates in childrens toys and child-care articles. But in terms of their use in vinyl plastics and personal care products, theres currently no specific legislation by other governmental agencies. Manufacturers decisions to reduce or eliminate the use of phthalates in these other products is largely voluntary. Thus theres still a long way to go.

For some products, its very doable to eliminate the use of ortho-phthalates. For example, there are other chemicals that you can use as plasticizers to soften vinyl plastic, and manufacturers have already made substitutions in some products. However, we do need to study what theyre using for substitute chemicalswhether theyre using other compounds that may also carry risks.

With personal care products, there are other chemicals that can be used besides phthalates. For instance, nail polish frequently contained one of the phthalates called dibutyl phthalate (DBP)it kept nail polish from being brittleand now there are formulations that dont contain DBP.

I think the goal of phthalate elimination from consumer products is achievable. Part of the reason were pushing for elimination is that its very hard for consumers to know what products ortho-phthalates are inespecially personal care products. If phthalates in the product are considered part of the scent formulation, they dont need to be listed on the ingredient list, because scents are considered proprietary. Even though some products do list phthalates, its really hard for consumers to read the labels with these long chemical names. Its really hard for even a very knowledgeable consumer to buy products and avoid phthalates.

Karen Feldscher

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The Big 3: Why phthalates should be restricted or banned from consumer products - HSPH News

Physiology

By providing the United States Army with more insight about individual physiology and the impacts of training in an extreme environment NeighborWebSJ…

By providing the United States Army with more insight about individual physiology and the impacts of training in an extreme environment NeighborWebSJ  NeighborWebSJ

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By providing the United States Army with more insight about individual physiology and the impacts of training in an extreme environment NeighborWebSJ...

Physiology

Compounds in green and black tea relax blood vessels by activating ion channel proteins – News-Medical.net

A new study from the University of California, Irvine shows that compounds in both green and black tea relax blood vessels by activating ion channel proteins in the blood vessel wall. The discovery helps explain the antihypertensive properties of tea and could lead to the design of new blood pressure-lowering medications.

Published in Cellular Physiology and Biochemistry, the discovery was made by the laboratory of Geoffrey Abbott, PhD, a professor in the Department of Physiology and Biophysics at the UCI School of Medicine. Kaitlyn Redford, a graduate student in the Abbott Lab, was first author of the study titled, "KCNQ5 potassium channel activation underlies vasodilation by tea."

Results from the research revealed that two catechin-type flavonoid compounds (epicatechin gallate and epigallocatechin-3-gallate) found in tea, each activate a specific type of ion channel protein named KCNQ5, which allows potassium ions to diffuse out of cells to reduce cellular excitability. As KCNQ5 is found in the smooth muscle that lines blood vessels, its activation by tea catechins was also predicted to relax blood vessels - a prediction confirmed by collaborators at the University of Copenhagen.

We found by using computer modeling and mutagenesis studies that specific catechins bind to the foot of the voltage sensor, which is the part of KCNQ5 that allows the channel to open in response to cellular excitation. This binding allows the channel to open much more easily and earlier in the cellular excitation process."

Geoffrey Abbott, PhD, Professor, Department of Physiology and Biophysics, UCI School of Medicine

Because as many as one third of the world's adult population have hypertension, and this condition is considered to be the number one modifiable risk factor for global cardiovascular disease and premature mortality, new approaches to treating hypertension have enormous potential to improve global public health. Prior studies demonstrated that consumption of green or black tea can reduce blood pressure by a small but consistent amount, and catechins were previously found to contribute to this property. Identification of KCNQ5 as a novel target for the hypertensive properties of tea catechins may facilitate medicinal chemistry optimization for improved potency or efficacy.

In addition to its role in controlling vascular tone, KCNQ5 is expressed in various parts of the brain, where it regulates electrical activity and signaling between neurons. Pathogenic KCNQ5 gene variants exist that impair its channel function and in doing so cause epileptic encephalopathy, a developmental disorder that is severely debilitating and causes frequent seizures. Because catechins can cross the blood-brain barrier, discovery of their ability to activate KCNQ5 may suggest a future mechanism to fix broken KCNQ5 channels to ameliorate brain excitability disorders stemming from their dysfunction.

Tea has been produced and consumed for more than 4,000 years and upwards of 2 billion cups of tea are currently drunk each day worldwide, second only to water in terms of the volume consumed by people globally. The three commonly consumed caffeinated teas (green, oolong, and black) are all produced from the leaves of the evergreen species Camellia sinensis, the differences arising from different degrees of fermentation during tea production.

Black tea is commonly mixed with milk before it is consumed in countries including the United Kingdom and the United States. The researchers in the present study found that when black tea was directly applied to cells containing the KCNQ5 channel, the addition of milk prevented the beneficial KCNQ5-activating effects of tea. However, according to Abbott, "We don't believe this means one needs to avoid milk when drinking tea to take advantage of the beneficial properties of tea. We are confident that the environment in the human stomach will separate the catechins from the proteins and other molecules in milk that would otherwise block catechins' beneficial effects."

This hypothesis is borne out by other studies showing antihypertensive benefits of tea regardless of milk co-consumption. The team also found, using mass spectrometry, that warming green tea to 35 degrees Celsius alters its chemical composition in a way that renders it more effective at activating KCNQ5.

"Regardless of whether tea is consumed iced or hot, this temperature is achieved after tea is drunk, as human body temperature is about 37 degrees Celsius," explained Abbott. "Thus, simply by drinking tea we activate its beneficial, antihypertensive properties."

Source:

Journal reference:

Redford, K.E., et al. (2021) KCNQ5 Potassium Channel Activation Underlies Vasodilation by Tea. Cellular Physiology and Biochemistry. doi.org/10.33594/000000337.

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Compounds in green and black tea relax blood vessels by activating ion channel proteins - News-Medical.net

Physiology

Regulation of the expression of human endogenous retroviruses (HERVs): elements in fetal development and a possible role in the development of cancer…

This article was originally published here

APMIS. 2021 Mar 8. doi: 10.1111/apm.13130. Online ahead of print.

ABSTRACT

Human endogenous retroviruses (HERVs) are remnants of ancient retroviral germline infections. Most HERV sequences are silenced in somatic cells, but interest is emerging on the involvement of HERV derived transcripts and proteins in human physiology and disease. A HERV-W encoded protein, syncytin-1, has been co-opted into fetal physiology, where it plays a role in trophoblast formation. Altered HERV transcription and expression of HERV derived proteins are associated with various cancer types and neurological diseases such as multiple sclerosis (MS). The implication of HERVs as potential mediators of both health and disease suggests important roles of regulatory mechanisms and alterations of these in physiological and pathological processes. The regulation of HERV sequences is mediated by a wide variety of mechanisms, and the focus of this review is on selected aspects of these, including epigenetic mechanisms such as CpG methylation and histone modifications of the HP1-H3K9me axis, viral transactivation events, and regulatory perspectives of transient stimuli in the microenvironment. Increasing knowledge of the regulation of HERV sequences will not only contribute to the understanding of complex pathogeneses, but may pinpoint potential targets for better diagnosis and treatment in complex diseases as MS.

PMID:33683784 | DOI:10.1111/apm.13130

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Regulation of the expression of human endogenous retroviruses (HERVs): elements in fetal development and a possible role in the development of cancer...

Physiology

environment. This new partnership will tap into real-time WHOOP physiological data to uncover insights that will create a blueprint for how soldiers…

Today, WHOOP, the human performance company, and the United States Army Paratroopers of the 4th Infantry Brigade Combat Team (Airborne), 25th Infantry Division, Spartan Brigade announced a first-of-its-kind study to examine the resiliency of soldiers operating in an Arctic environment. This new partnership will tap into real-time WHOOP physiological data to uncover insights that will create a blueprint for how soldiers train, fight, and manage stress in the most extreme military conditions.

1,000 Spartan Brigade paratroopers at Joint Base Elmendorf-Richardson, Alaska are currently wearing WHOOP Strap 3.0 to measure daily strain, recovery rates, sleep quality, and more as part of a six-month study in collaboration with the University of Queensland. The 24/7 health monitor is built to withstand the rigors of military use with a waterproof, unobtrusive design plus five-day battery life with on-the-go charging. WHOOP is also uniquely suited for tactical performance with wearability from wrist to upper arm and no Wifi, GPS, or geolocation capabilities.

Previous research has typically focused on investigating stress in laboratory settings using standardized stress tasks, said Kristen Holmes, VP of Performance Science at WHOOP and Principle Investigator on the study. We are carrying this study out in the field to better understand how personal, psychological and situational factors can impact a soldier while training during extreme Arctic conditions. We are proud to support our troops in an innovative way and this data could be a critical tool for the military to improve soldier resiliency at a time when mental health issues, and suicide rates are higher than ever.

By providing the United States Army with more insight about individual physiology and the impacts of training in an extreme environment, soldiers will be better equipped to manage stress and ultimately, have higher readiness. All leaders from the squad level, NCOs and above, will have access to their paratroopers data, so they can adjust training and operational plans to maximize the health and readiness of their teams.

Imagine as a squad leader that you have a paratrooper that has had an abnormally low recovery for several days, said the Spartan Command Sergeant Major Alex Kupratty, Maybe your platoon has been in the field for weeks, or the paratrooper just returned from an Army school. Now, you have the data to better help them recover, or to adjust your training to match the teams needs.

The research project will analyze personalized data like heart rate variability, resting heart rate, cardiovascular strain, and respiratory rate to also create a biometric baseline for the Spartan Brigade grounded in overall resilience, stress, and sleep quality. Unlike blind studies, the participating paratroopers will have immediate access to their own data, as well as techniques to maximize recovery, and can make decisions using this feedback to optimize their personal performance.

WHOOP provides seamless and highly reliable biometric capture, thereby producing objective measures of sleep quality and recovery, which are of central importance to our research, said Dr. William von Hippel, lead investigator on the study and professor at The University of Queensland. Once the data are analyzed, we hope to uncover insights the military could leverage to enhance training regimens and maximize soldier preparedness.

The study will conclude in May and full findings will be submitted for peer review this summer. Learn more about this ongoing research from Chief Warrant Officer 4 Phillip Ranck, study project leader for the Spartan Brigade, on the WHOOP Podcast at WHOOP.com/thelocker/US Army Study.

About WHOOPWHOOP, the human performance company, provides a membership for 24/7 coaching to improve health. The WHOOP membership comes with free hardware (the new Whoop Strap 3.0), a coaching platform designed to optimize your behavior, and a community of high performers. WHOOP members range from professional athletes and Fortune 500 CEOs to fitness enthusiasts and endurance competitors to executives and military personnel. Studies show WHOOP can positively change behavior, increase sleep, and improve physiological biomarkers. Founded in 2012, WHOOP is based in Boston and has raised more than $200 million in venture capital. Visit whoop.com for the latest company news and connect with WHOOP on Instagram, Twitter, Facebook, and YouTube.

About the United States Army Paratroopers of the 4th Infantry Brigade Combat Team (Airborne), 25th Infantry Division, Spartan BrigadeThe Spartan Brigade, based in Alaska, is the only Arctic airborne infantry brigade combat team. Spartan paratroopers are the only U.S. Army paratroopers that conduct airborne operations across the Arctic and Pacific theaters.

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environment. This new partnership will tap into real-time WHOOP physiological data to uncover insights that will create a blueprint for how soldiers...

Physiology

Working with the menstrual cycle: Female optimised training coming soon to road.cc – road.cc

Its International Womens Day, so what better time to let you all know about something Ive been itching to say is coming up on road.cc

Female physiology:its very different to mensso why are we all training like men? Well, for such a long time we havent known any different, as research barely touches on training specifically regarding womens hormones. But that is starting to change, so join me along my journey in discovering how to train with my body and turn tracking my period away from being oh, is it that time of the month ALREADY, towards my means of making the most of when Im at my strongest.

So coming up

Ill be sharing my experiences of completing one menstrual-cycle-long training block where each session is optimised for my body and aligned with my menstrual cycle. Ill be recording this for a vlog that will appear on road.ccs YouTube channelgive it a cheeky subscribe here so you dont miss out

This upcoming vlog is going to look at how the intensity of the sessions should be varied during each phase of the menstrual cyclesuch as which stage its best to pack in the hard workouts as this is when the female hormones enable us to be our strongest (looking at both strength and endurance), and when its sensible to rein it in a little. All of this will be backed up with links back to the science.

The optimised training block will be prescribed to me based on the symptoms I experience across my natural period cycle, which is usually 29 to 30 days long (not that far off the national average of 28)*, by cycling coach Jasmijn Muller of BE THE EGG Cycle Coaching. She was one of just 50 people to take part in Dr Stacy Sims inaugural Women are Not Small Men 2019 course, and in August 2020, she was once again one of the guinea pigs for Dr Stacy Sims Menopause for Athletes course.

Jasmijn applies all of what she learnt from the courses with Dr Stacy Sims with her female clients but also continues to stay up to date with the latest literature and webinars on the subject of exercise and hormones. Im so excited to be guided through this new approach to training by someone so across the current research, as well as having practical experience form coaching female clients in this way week in week out.

Your physiology, your hormones and your training are all aligned,Jasmijn says. Progressive overload followed by a short de-load on a standardised 3 weeks on, 1 week off pattern frequently applied to men does not permit women to take advantage of optimal training adaptations the way they can if they match their training intensity to their physiology and hormone levels.

In men you only have in-day fluctuations in hormone levels to consider; in women, it differs from day to day.

By rejigging your training schedule to do the hard stuff when your hormones allow you to do the hardest stuff, and by backing off a little bit when youre in a different hormonal environment, you get better results.

But as well as optimising the training plan to schedule sessions when the hormones empower you to be at your best, Jasmijn also looks at ways to reduce the effect menstrual-related symptoms have on you and your training, providing more flexibility with when you can execute certain sessions and, perhaps more importantly, events and races which are at a fixed date on the calendar.

In theory, you may want to schedule a particular training session at a particular time of the month, but in practice, with our hormones we dont have that luxury so its also about learning how we can mitigate for some menstrual symptoms, Jasmijn says. Yoga, nutrition and hydration can all be utilised

The natural menstrual cycle is divided into two distinct phases, Jasmijn explains. Day one is when bleeding begins and this first half of the cycle is called the follicular phase. The second half is the lutealphase and in between the two, ovulation takes place.

Dr Stacy Sims refers to the follicular phase as being the low hormone phase, as progesterone is low throughout and oestrogen-only starts to rise later. While the luteal is the high hormone phase as both progesterone and oestrogen are raised during this phase, Jasmijn says.

Over the course of the vlog, Jasmijn will guide me through the hormones in each of these phases, the impact and logic of the training sessions she has set, as well as nutritional support and mitigation for performance and recovery.

Already following Jasmijns advice, Ive been using the Wild.Ai app for the last month to note down when I bled, for how long and how heavy, as well as the symptoms Ive been experiencing during my menstruation and across other parts of the cycle.

As with all training, by tracking and analysing responses to different sessions over time, more can be done to adapt the plan to further optimise specific symptoms.

While women are not the same as men, not all women are the same as all women, either. This vlog will provide an insight into female physiology, whats going in each phase of the natural period cycle, and although the lengths of these do vary slightly womanto woman,most of the same principles apply.

Its all well and good having the optimal training, but having a bike that gives you the confidence to push your limits, as well as the platform to power through to PBs when youre at your strongest each month, is all part of it.

Massive thanks to Ribble for kitting me out with the Endurance SL R Disc as ridden by the Drops Le Col team. I'm looking forward to smashing some sessions on it.

Ribbles approach to womens bikes has always gelled with my belief about whats the best approach. Its also great to see their recent involvement with professional womens cycling with the Drops Le Col team and I am super pleased to have their support (which has come with lots of enthusiasm) with this project and raising awareness of female optimised training.

Sasha Castling, Head of PR at Ribble says: Weve had a long association with pro teams and becoming involved with womens professional cycling has been discussed at board level for quite some time. When the Drops Le Col supported by Tempur partnership was suggested we jumped at the opportunity.

It is a key point of difference for us to talk specifically and appeal to women and not to simply shrink and pink our range. Experts at our physical retail stores can discuss the specific requirements of our customers including sizing with a personalised bike fitting. Our website also has a one-way video call feature to engage with our experts and gain a greater insight into the bike range and answer any questions. Our Bike Builder tool allows the customer to tailor the specification all contact points can be changed,from the saddle, bar width to stem and crank lengths etc. We also have the option of Custom Colour giving the riders the freedom to create their own unique statement design.

The Drops Le Col partnership has only just begun and we are already in conversations about how we can work together to use the teams experience and insight to help educate and promote the aspects of the life of a professional cyclist and how this can benefit the lives of all our female customers. We are incredibly proud to support the team and look forward to ways in which we can shine a spotlight on womens cycling and enrich the wonderful world cycling can offer to women as a whole, together.

It's great to be working with Anna and road.cc in supporting this feature and highlighting this subject, launched to align with International Womens Day, and to follow her journey.

While all training is completed to get fitter, I have my sights on racing the cyclo-cross season for the first time** and so the training Jasmijn will be assigning me will work towards improving my fitness for the CX efforts as part of my preparation for some mudfest action.

The CX season doesnt start until the autumn, so Im not currently tapering or peaking for an upcoming event. This block is all about optimising a regular months training to my natural period cycle to get stronger for cyclo-cross related efforts.

As this learning experience is all centred around when my body decides its time to bleed, I plan to start this training block (and month vlog) on 18 March, and so hopefully the vlog will land at the end of April.

I can quite honestly say that normally when I feel the dreaded slight ache of my lower back that instantly puts me in a foul mood (which is made slightly better by giving in to my craving of eating copious amounts of chocolateGalaxy, and lots of it) because I know Im about two days away from mega cramp day, AKA day one of bleeding.

But, in an unexpected turn of events, Im really quite excited as this wont just be day one of bleeding, but day one of training with my cycle, and not against it.

Subscribe to the road.ccs YouTube to find out what training Jasmijn recommends at each phase of the natural menstrual cycle and how I get on following this optimised training

*Just want to put out there that although my menstrual cycle is regular now and close to the average of 28 days, its not always been this stable or so average. Up until two years ago Id go at least 60 days without one because of issues related to under-eating with training (which is another important subject!). With support, this is something Ive managed to address, and since then my cycle length has been gradually shortening until it stabilised at the point it is nowits been like this for the last year or so. It genuinely was a personal victory for me to be back in a position where my bodys natural processes are functioning more like they should be. With this, I am in a position where I can share my experiences of optimising training around the average length menstrual cycle. But I just wanted to share that although my menstrual cycle may seem close to normal or average, its not always been the case for me either and Im conscious there are lots of other female cyclists for whom my previous situation would actually be more relatable. Theres so much to training with the female physiology, and this vlog is just the beginning of touching on such a large and important subject matter.

**Some racing background: Ima roadie through and through when it comes to racing and technical skills have never been my forte. However, its always an area Ive wanted to improve on, and this year with the uncertainty of what will be of the regional and national road season, I see it as the perfect chance to get stuck into the slop (hopefully not that literally). Also, as Im much more convinced the whole CX season will take place, it feels like a tangible targetto focus on.

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Working with the menstrual cycle: Female optimised training coming soon to road.cc - road.cc

Physiology

Researchers discover a backup natural pacemaker in the heart – The University of Manchester

Researchers at The University of Manchester and Manchester University NHS Foundation Trust have discovered a backup natural pacemaker, which is able to generate a pulse and control the heart rate.

The British Heart Foundation funded study completely changes our understanding of the hearts anatomy and has important implications on the work of cardiologists and heart surgeons.

As part of the study, published in Frontiers in Physiology, University scientists carried out research involving 15 goats.

Subsequent data analysis found that a subsidiary atrial pacemaker (SAP) takes over from the nearby sinoatrial, or SA Node, the primary way the heart generates electrical signals that make it beat, when it fails.

Lead author Dr Halina Dobrzynski, from The University of Manchester, said: This study completely reshapes our understanding of the how the heart works and is tremendously exciting. It builds on our work on the human heart over many years and we hope will make an important contribution to future treatments.

Co-author, Dr Gwilym Morris, a clinical researcher at The University of Manchester and a Consultant Cardiologist at Manchester Royal Infirmary, part of Manchester University NHS Foundation Trust, (MFT), worked on the data analysis strand of the project.

He said: Not only will this knowledge improve our understanding of the anatomy of the heart which is crucial for clinicians it will give patients the full facts so they can make a more informed choice about ablation.

The SA node in human, goat and other mammalian species is a group of cells located in the wall of the right atrium of the heart which have the ability to spontaneously produce the electrical impulses to make our hearts beat.

The team are confident the discoveries are highly relevant to the human heart, as the organ in goats has similar anatomy and physiology, producing a similar heart rate.

When the SA node doesnt work as it should, the heart rate can slow down causing breathlessness and blackouts.

However, when the malfunctioning SA node is removed by cardiologists in a procedure known as ablation, the new structure discovered by the team carrying out the research in goats took over as the dominant pacemaker, which also drives electrical activity of the heart.

And even though electrocardiograms (ECGs) which provide an electrical map of the heart have slightly different shapes for each natural pacemaker, the heart still functioned normally when using the SAP.

The study also explains why ablation of the SA node - sometimes performed by cardiologists to treat a fast heartbeat called inappropriate sinus tachycardia - is often unsuccessful.

The research shows that the SA node is difficult to completely destroy using ablation and even if a few cells of the SA node are left, they find, it will continue to function as the hearts pacemaker.

Dr Morris added: Im excited that we also intend as a team to produce a 3D reconstruction of the whole heart, which will depict the new structure. And that will be a helpful tool for helping patients to understand the pros and cons of having an ablated SA node.

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Researchers discover a backup natural pacemaker in the heart - The University of Manchester

Physiology

Menopausal changes may drive a heightened appetite for fatty foods and weight gain – News-Medical.Net

A new study in mice suggests that declining estrogen levels lower the taste buds' sensitivity to fats, which may drive a heightened appetite for fatty foods-;and weight gain-;after menopause. The study is published ahead of print in the American Journal of Physiology-Endocrinology and Metabolism. It was chosen as an APSselect article for March.

Previous research has shown that the hormone estrogen plays a role in appetite, food intake and body weight. However, there has been little study of sex differences within the taste system-;which includes cells in the taste buds that respond to different flavors (salt, sour, sweet, bitter, umami and fat) and activate hormone signaling throughout the body. "The taste system plays an important role in nutrient recognition and therefore shaping the diet," researchers of a new study wrote.

The researchers explored how estrogen activates fat taste signaling in male and female (pre- and postmenopausal) mice through a "bottle test" in which the animals were free to choose either plain water or water mixed with linoleic acid, a form of fatty acid. The research team also analyzed gene expression and signaling response in taste cells treated with estrogen.

The premenopausal female mice tended to drink less of the fatty acid-laced drink than water. This finding corresponded with the cell experiments that showed a greater response to fatty acids than in the males and postmenopausal females. The male and postmenopausal female mice-;both having lower circulating estrogen levels than the premenopausal females-;showed an increased preference for the fat-laden beverage over water.

In other words, "after loss of estrogen signaling, females [are] less responsive to the chemical cues in dietary fats leading them to eat more and put on more weight than when premenopausal," explained Timothy A. Gilbertson, PhD, of the University of Central Florida and corresponding author of the study.

These results in a mouse model could, in part, translate into why women have a harder time losing weight after menopause, Gilbertson said.

Source:

Journal reference:

Dahir, N.S., et al. (2021) Sex differences in fat taste responsiveness are modulated by estradiol. American Journal of Physiology-Endocrinology and Metabolism. doi.org/10.1152/ajpendo.00331.2020.

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Menopausal changes may drive a heightened appetite for fatty foods and weight gain - News-Medical.Net

Physiology

Students’ declining ability in maths and science a concern – Stuff.co.nz

David Unwin/Stuff

New Zealand students are falling behind with their achievements in maths and science, according to an international study.

OPINION: Its no secret New Zealand school students are falling further behind in maths and science knowledge compared with other countries.

The Trends in International Mathematics and Science Study is performed every four years. If focuses on assessing student achievement in maths and science at middle primary (year 5) and lower secondary (year 9) levels around the world.

Its co-ordinated in the United States and in New Zealand managed by the Education Ministry.

Our year 9 students maths ability now ranks 23rd out of 39 countries, and in science its 17th from 35. Fair to middling in comparison, but these are decreases from the 2014 survey and notably worse than 15 years ago.

READ MORE:* When two plus two equals 40 - NZ's problem with maths* Don't panic about poor Kiwi science test results* Results in maths and science 'a worrying trend'

While our own Einsteins (outliers) will still pop up occasionally and become tomorrows McDiarmids and Callaghans, it means the general ability of the average New Zealand young person to think like a scientist, or solve a maths-based problem, is declining.

And there will be outliers in the direction of Homer Simpson as well.

Maybe if a youngster has his or her heart set on being a manicurist or rugby player, maths and science ability is not especially useful. But at least a rudimentary understanding of maths is pretty useful for budgeting or building a deck.

I have three degrees, all science based. The first was a bachelor of science in agriculture, which provided a terrific grounding in much of the physical sciences, physics, chemistry and maths, as well as life-sciences, physiology, biology, botany etc.

My latter post-graduate education was in human nutrition and physiology, but there I often relied on my basic physical science knowledge to help understand the esoteric nature of what I was trying to get my head around.

The biggest impact this science knowledge has had on me is that I now act like a scientist as I live my life as an environmentally aware citizen and small business owner.

I make sure the doors are closed in winter to keep the cold air out, drive carefully to reduce fuel use and save money, and model sales from previous years to see when its best to take a holiday. I even wear jandals and socks at home in winter to stop my body heat dissipating into the cold kitchen floor.

Being a scientist is more than actions, its a way of thinking. My science career taught me to ask if something can be done better, or whether there is an alternative explanation for some observation.

It means challenging dogma, asking the questions, entering a debate armed with data, or questioning the narrative. These can make you unpopular, especially in New Zealand.

Being a scientist is not about assuming someone is right without taking the time to form an evidence-based opinion. No-one, after all, has won a Nobel Prize in medicine-physiology for re-hashing knowledge from a text book.

And scientists dont resort to name calling someone who disagrees with them or the current and popular explanation. Good science enables and encourages robust debate, but wins the debate with weight of empirical evidence.

My worry is that the next generation, whose grasp of science and mathematics is less than the previous, wont be able to think scientifically on a day-to-day basis.

They wont understand the importance of simple things such as enabling airflow to keep a house dry, using a longer lever to get your wheel nuts off, or exercising to keep warm. They wont draw a conclusion and win an argument based on evidence, but rather rely on weight of media exposure.

And when scientifically naive people are in charge and make decisions based solely on popularity and emotion, we will be in trouble.

Perhaps we should not be surprised that all sorts of quirky and popular theories and conspiracies are now so easily accepted. They are probably lacking a good school science education.

Steve Stannard is a Palmerston North business owner and former academic.

More:
Students' declining ability in maths and science a concern - Stuff.co.nz

Physiology

Six KSOM departments make top 10 in NIH funding nationally | Keck School of Medicine of USC – USC News

Ophthalmology is No. 1 among med schools for the fourth year in a row, while Preventive Medicine is No. 2

(Photo/iStock)

By Landon Hall

Data on grants awarded from the National Institutes of Health have been released, and the Keck School of Medicine of USC has six departments in the top 10 in their respective fields.

KSOMs Ophthalmology Department is again ranked No. 1 among medical schools in the country. Preventive Medicine, which has covered a wide variety of research topics in recent years and has opened a new COVID-19 research center, is No. 2 in funding.

Rounding out the Top 10 is Neurology at No. 4; Physiology and Neuroscience at No. 5; Otolaryngology at No. 7; and Orthopaedic Surgery at No. 9.

The rankings are based on data compiled by theBlue Ridge Institute for Medical Research.

Were competing better than we used to, said Tom Buchanan, MD, professor of medicine, the Bernard J. Hanley Chair in Medicine and the schools Vice Dean for Research.

He noted how difficult it is to secure an NIH grant, which is based on merit. It takes a good fundamental idea, it takes preliminary data that the idea could be right, and a proposal that is feasible and scientifically very vigorous.

J. Martin Heur, MD, Interim Chair of the Department of Ophthalmology, said: This continues our streak of being ranked No. 1 for four consecutive years and is a testament to the quality of research being carried out in our department. I would like to congratulate everyone in the department for this fantastic achievement.

Preventive Medicine held steady at No. 2.

The Department of Preventive Medicine is once again proud to have gained this re-affirmation of the research strength of its faculty, said Howard Hu, MD, MPH, ScD, the Flora L. Thornton Chair of the Department of Preventive Medicine.Behind the numbers is a deep and abiding commitment to generate the scientific evidence that is essential for optimizing the health of large and diverse urban populations, locally and globally.

Neurology, led by Helena Chui, MD, the Raymond and Betty McCarron Chair in Neurology, rose from No. 9 to No. 4.

The KSOM Department of Neurology is gratified to be ranked No. 4 in NIH funding, Chui said. Over the past decade, USC has made key strategic investments in neuroscience. Our approach has been two-pronged: recruiting topflight talent and supporting our own investigators.

Otolaryngology rose from No. 10 to No. 7. Of course, the research funding itself is not the goal; the goal is discovery, said John Oghalai, MD, Chair of Otolaryngology Head and Neck Surgery, and the Leon J. Tiber and David S. Alpert Chair in Medicine. I am so grateful for the efforts of our faculty, trainees, and staff to understand the basic mechanisms of biology, to discover the mechanisms of disease, and to develop new diagnostics and cures that will help society.

Physiology and Neuroscience, chaired by Berislav V.Zlokovic, MD, PhD, boasts a formidable team of researchers working on some of the most pressing problems in health, including Alzheimers disease.

Jay R. Lieberman, chair of Orthopaedic Surgery, said: Our goal in the Department of Orthopaedic Surgery is to continually innovate to provide our patients with the best care possible, and in our research laboratories we are developing novel treatment regimens for our patients. We have a special interest in translational research focused on stem cell therapies to enhance bone and cartilage repair, muscle and tendon regeneration, and spinal fusion.

To learn more about KSOMs groundbreaking work, visit our Research page.

Link:
Six KSOM departments make top 10 in NIH funding nationally | Keck School of Medicine of USC - USC News