Monthly Archives: March 2021

Cell Biology

The Mystery of the Missing Energy in Singlet Fission Solar Cells Solved – SciTechDaily

Yuttapoom Puttisong, Senior Lecturer in the Department of Physics, Chemistry and Biology at Linkping University. Credit: Thor Balkhed

Competition between triplet pair formation and excimer-like recombination controls singlet fission yield.

The efficiency of solar cells can be increased by exploiting a phenomenon known as singlet fission. However, unexplained energy losses during the reaction have until now been a major problem. A research group led by scientists at Linkping University, Sweden, has discovered what happens during singlet fission and where the lost energy goes. The results have been published in the journal Cell Reports Physical Science.

Solar energy is one of the most important fossil-free and eco-friendly sustainable sources of electricity. The silicon-based solar cells currently in use can at most use approximately 33% of the energy in sunlight and convert it to electricity. This is because the packets of light, or photons, in the suns beams have an energy that is either too low to be absorbed by the solar cell, or too high, so that part of the energy is dissipated to waste heat. This maximum theoretical efficiency is known as the Shockley-Queisser limit. In practice, the efficiency of modern solar cells is 20-25%.

Diphenyl hexatriene (DPH) was used as singlet fission material in this study. Credit: Thor Balkhed

However, a phenomenon in molecular photophysics known as singlet fission can allow photons with higher energy to be used and converted to electricity without heat loss. In recent years, singlet fission has attracted increasing attention from scientists, and intense activity is underway to develop the optimal material. However, unexplained energy losses during singlet fission have until now made it difficult to design such a material. Researchers have not been able to agree on the origin of these energy losses.

Now, researchers at Linkping University, together with colleagues in Cambridge, Oxford, Donostia, and Barcelona, have discovered where the energy goes during singlet fission.

Singlet fission takes place in less than a nanosecond, and this makes it extremely difficult to measure. Our discovery allows us to open the black box and see where the energy goes during the reaction. In this way we will eventually be able to optimize the material to increase the efficiency of solar cells, says Yuttapoom Puttisong, senior lecturer in the Department of Physics, Chemistry and Biology at Linkping University.

View from the inside of the magneto-optic instrument that helps Yuttapoom Puttisong and his team to develop a protocol in searching for energy loss in singlet fission. Credit: Thor Balkhed

Part of the energy disappears in the form of an intermediate bright state, and this is a problem that must be solved to achieve efficient singlet fission. The discovery of where the energy goes is a major step on the way to significantly higher solar cell efficiency from the current 33% to over 40%.

The researchers used a refined magneto-optical transient method to identify the location of energy loss. This technique has unique advantages in that it can examine the fingerprint of the singlet fission reaction at a nanosecond timescale. A monoclinic crystal of a polyene, diphenyl hexatriene (DPH), was used in this study. However, this new technique can be used to study singlet fission in a broader material library. Yuqing Huang is a former doctoral student in the Department of Physics, Chemistry and Biology at Linkping University, and first author of the article now published in a newly established journal, Cell Reports Physical Science.

The actual singlet fission process takes place in the crystalline material. If we can optimize this material to retain as much as possible of the energy from the singlet fission, we will be significantly closer to application in practice. In addition, the singlet fission material is solution-processable, which makes it cheap to manufacture and suitable for integration with existing solar cell technology, says Yuqing Huang.

Reference: Competition between triplet pair formation and excimer-like recombination controls singlet fission yield by Yuqing Huang, Irina A. Buyanova, Chanakarn Phansa, Maria E. Sandoval-Salinas, David Casanova, William K. Myers, Neil C. Greenham, Akshay Rao, Weimin M. Chen and Yuttapoom Puttisong, 8 February 2021, Cell Reports Physical Science.DOI: 10.1016/j.xcrp.2021.100339

The research has been funded principally by the Swedish Research Council and the Knut and Alice Wallenberg Foundation.

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The Mystery of the Missing Energy in Singlet Fission Solar Cells Solved - SciTechDaily

Cell Biology

Meet The UKs First Synthetic Biology Unicorn – Forbes

Jonny Ohlson, Executive Chairman of Touchlight

The genetic medicine industry is growing rapidly, increasing the demand for DNA at an exponential rate. This need is being driven even higher as more companies focus on manufacturing COVID-19 vaccines and other types of mRNA products.

Synthetic biology has the potential to revolutionize this emerging industry and solve the DNA supply problem for genetic medicine. Recent advances in pure, synthetic DNA from Touchlight in the United Kingdom could be the type of disruptive technology that manufacturers need to scale.

Genetic medicine focuses on using DNA and RNA to deliver therapeutics. Vaccines and other products that rely on mRNA are a growing sector in the synthetic biology industry. These novel therapeutics create the possibility for safer and more effective personalized treatments.

The demand for COVID-19 vaccines has highlighted the importance of mRNA products. mRNA vaccines rely on non-viral vectors for delivery, which means they are faster to manufacture because they can be made through synthetic production.

"We are constantly being challenged by diseases. And we have to find new, efficient and safe ways to vaccinate. Going forward, mRNA vaccines will continue to be important," says Executive Chairman of Touchlight, Jonny Ohlson.

Since genetic medicine and vaccines need DNA for manufacturing, the demand for these key materials is growing. Today, if a new mRNA product goes to market, it could use up 50% of the world's current DNA supply. And there are many mRNA products in different clinical phases that will need even more DNA.

"We are speaking to mRNA manufacturers, and they need kilograms of DNA now," says Ohlson. "Some vaccine makers will need hundreds of kilograms of DNA in the future. We estimate that the world's current supply of DNA is about 3 kilograms per year." A kilogram of DNA may not sound like a lot. But considering that DNA is made up of microscopic molecules, a single kilogram of DNA represents a significant volume.

Traditional DNA manufacturing relies on plasmids and bacterial fermentation. However, this method will no longer be able to meet the supply needs of manufacturers because of its expense and slow turnaround.

A scientist works in the lab at Touchlight where the company can produce up to a kilogram of DNA a ... [+] month.

Synthetic biology offers a solution to help companies obtain significantly larger quantities of DNA. Touchlight's synthetic DNAcalled dbDNA (doggybone DNA)offers unique advantages over both plasmid and other DNA formats."dbDNA can do all the things plasmid DNA can do and a lot more. It's better, cheaper, and faster," says Ohlson.

Manufactured through a completely synthetic process in a cell-free environment, dbDNA is a linear, double-stranded DNA vector. Producing dbDNA is much faster than producing plasmid DNA, taking weeks instead of months. Additionally, the equipment to make dbDNA has a smaller manufacturing footprint than plasmids, so companies can more easily scale production.

Touchlight's dbDNA also has the benefit of being pure DNA, unlike plasmids. When plasmid DNA is amplified, it creates a product with antibiotic resistance genes, origins of replication, and other unwanted pieces. However, Touchlight uses two enzymes to amplify synthetic DNA to scale without any impurities or bacterial sequences.

Unwanted bacterial sequences are a big problem for genetic medicine because they interfere with the goals of the final product, such as a therapeutic having an unexpected immune effect. Pure DNA like dbDNA is safer and eliminates these types of problems.

Touchlight just announced a funding round of 42 million ($60 million) led by Bridford Investments Limited. The company plans to triple its manufacturing space and increase its production of DNA up to 1 kilogram per month by the first quarter of 2022.

The funds will also help the company add 11 new state-of-the-art DNA production suites for a total of 15 and create up to 60 new jobs. However, the company's unique benchtop technology means the total facility footprint will only be 7,500 square feet, which is a fraction of the space needed for plasmid DNA manufacturing.

Genetic medicine looks to be the future of therapeutics. Novel vaccines, cell and gene therapies all have the potential to transform lives. And, as many predict that COVID-19 will not be the last pandemic that requires rapid vaccinations, mRNA vaccines will continue to be of global therapeutic importance. Synthetic biology could hold the key to helping companies scale production of vaccines and other, critical DNA and RNA-based therapies.

Thank you toLana Bandoimfor additional research and reporting in this article. Im the founder of SynBioBeta, and some of the companies that I write about are sponsors of the SynBioBeta conference andweekly digest.

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Meet The UKs First Synthetic Biology Unicorn - Forbes

Cell Biology

Original Error: Retracing the History of the Mutation That Gave Rise to Cancer Decades Later – SciTechDaily

There is no stronger risk factor for cancer than age.

At the time of diagnosis, the median age of patients across all cancers is 66. That moment, however, is the culmination of years of clandestine tumor growth, and the answer to an important question has thus far remained elusive: When does a cancer first arise?

At least in some cases, the original cancer-causing mutation could have appeared as many as 40 years ago, according to a new study by researchers at Harvard Medical School and the Dana-Farber Cancer Institute.

Reconstructing the lineage history of cancer cells in two individuals with a rare blood cancer, the team calculated when the genetic mutation that gave rise to the disease first appeared. In a 63-year-old patient, it occurred at around age 19; in a 34-year-old patient, at around age 9.

The findings, published in the March 4, 2021, issue of Cell Stem Cell, add to a growing body of evidence that cancers slowly develop over long periods of time before manifesting as a distinct disease. The results also present insights that could inform new approaches for early detection, prevention, or intervention.

For both of these patients, it was almost like they had a childhood disease that just took decades and decades to manifest, which was extremely surprising, said co-corresponding study author Sahand Hormoz, assistant professor of systems biology at HMS and Dana-Farber.

I think our study compels us to ask, when does cancer begin, and when does being healthy stop? Hormoz said. It increasingly appears that its a continuum with no clear boundary, which then raises another question: When should we be looking for cancer?

In their study, Hormoz and colleagues focused on myeloproliferative neoplasms (MPNs), a rare type of blood cancer involving the aberrant overproduction of blood cells. The majority of MPNs are linked to a specific mutation in the gene JAK2. When the mutation occurs in bone marrow stem cells, the bodys blood cell production factories, it can erroneously activate JAK2 and trigger overproduction.

To pinpoint the origins of an individuals cancer, the team collected bone marrow stem cells from two patients with MPN driven by the JAK2 mutation. The researchers isolated a number of stem cells that contained the mutation, as well normal stem cells, from each patient, and then sequenced the entire genome of each individual cell.

Over time and by chance, the genomes of cells randomly acquire so-called somatic mutationsnonheritable, spontaneous changes that are largely harmless. Two cells that recently divided from the same mother cell will have very similar somatic mutation fingerprints. But two distantly related cells that shared a common ancestor many generations ago will have fewer mutations in common because they had the time to accumulate mutations separately.

Analyzing these fingerprints, Hormoz and colleagues created a phylogenetic tree, which maps the relationships and common ancestors between cells, for the patients stem cellsa process similar to studies of the relationships between chimpanzees and humans, for example.

We can reconstruct the evolutionary history of these cancer cells, going back to that cell of origin, the common ancestor in which the first mutation occurred, Hormoz said.

Combined with calculations of the rate at which mutations accumulate, the team could estimate when the JAK2 mutation first occurred. In the patient who was first diagnosed with MPN at age 63, the team found that the mutation arose around 44 years prior, at the age of 19. In the patient diagnosed at age 34, it arose at age 9.

By looking at the relationships between cells, the researchers could also estimate the number of cells that carried the mutation over time, allowing them to reconstruct the history of disease progression.

Initially, theres one cell that has the mutation. And for the next 10 years theres only something like 100 cancer cells, Hormoz said. But over time, the number grows exponentially and becomes thousands and thousands. Weve had the notion that cancer takes a very long time to become an overt disease, but no one has shown this so explicitly until now.

The team found that the JAK2 mutation conferred a certain fitness advantage that helped cancerous cells outcompete normal bone marrow stem cells over long periods of time. The magnitude of this selective advantage is one possible explanation for some individuals faster disease progression, such as the patient who was diagnosed with MPN at age 34.

In additional experiments, the team carried out single-cell gene expression analyses in thousands of bone marrow stem cells from seven different MPN patients. These analyses revealed that the JAK2 mutation can push stem cells to preferentially produce certain blood cell types, insights that may help scientists better understand the differences between various MPN types.

Together, the results of the study offer insights that could motivate new diagnostics, such as technologies to identify the presence of rare cancer-causing mutations currently difficult to detect, according to the authors.

To me, the most exciting thing is thinking about at what point can we detect these cancers, Hormoz said. If patients are walking into the clinic 40 years after their mutation first developed, could we have caught it earlier? And could we prevent the development of cancer before a patient ever knows they have it, which would be the ultimate dream?

The researchers are now further refining their approach to studying the history of cancers, with the aim of helping clinical decision-making in the future.

While their approach is generalizable to other types of cancer, Hormoz notes that MPN is driven by a single mutation in a very slow growing type of stem cell. Other cancers may be driven by multiple mutations, or in faster-growing cell types, and further studies are needed to better understand the differences in evolutionary history between cancers.

The teams current efforts include developing early detection technologies, reconstructing the histories of greater numbers of cancer cells, and investigating why some patients mutations never progress into full-blown cancer, but others do.

Even if we can detect cancer-causing mutations early, the challenge is to predict which patients are at risk of developing the disease, and which are not, Hormoz said. Looking into the past can tell us something about the future, and I think historical analyses such as the ones we conducted can give us new insights into how we could be diagnosing and intervening.

Reference: Reconstructing the Lineage Histories and Differentiation Trajectories of Individual Cancer Cells in Myeloproliferative Neoplasms by Debra Van Egeren, Javier Escabi, Maximilian Nguyen, Shichen Liu, Christopher R. Reilly, Sachin Patel, Baransel Kamaz, Maria Kalyva, Daniel J. DeAngelo, Ilene Galinsky, Martha Wadleigh, Eric S. Winer, Marlise R. Luskin, Richard M. Stone, Jacqueline S. Garcia, Gabriela S. Hobbs, Fernando D. Camargo, Franziska Michor and Ann Mullally, 22 February 2021, Cell Stem Cell.DOI: 10.1016/j.stem.2021.02.001

Study collaborators include scientists and physicians from Brigham and Womens Hospital, Boston Childrens Hospital, Massachusetts General Hospital, and the European Bioinformatics Institute. The other co-corresponding authors of the study are Ann Mullally and Isidro Corts-Ciriano.

Additional authors include Debra Van Egeren, Javier Escabi, Maximilian Nguyen, Shichen Liu, Christopher Reilly, Sachin Patel, Baransel Kamaz, Maria Kalyva, Daniel DeAngelo, Ilene Galinsky, Martha Wadleigh, Eric Winer, Marlise Luskin, Richard Stone, Jacqueline Garcia, Gabriela Hobbs, Fernando Camargo, and Franziska Michor.

The study was supported in part by the National Institutes of Health (grants R00GM118910, R01HL158269), the Jayne Koskinas Ted Giovanis Foundation for Health and Policy, the William F. Milton Fund at Harvard University, an AACR-MPM Oncology Charitable Foundation Transformative Cancer Research grant, Gabrielles Angel Foundation for Cancer Research, and the Claudia Adams Barr Program in Cancer Research.

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Original Error: Retracing the History of the Mutation That Gave Rise to Cancer Decades Later - SciTechDaily

Physiology

Re: Vitamin D and covid-19: ignorance of physiology and evolution – The BMJ

Dear Editor

Once again we read a selective approach to evaluating the role of this autocrine signal in the pandemic. The authors do not acknowledge the primacy of physiology in medicine. The physiological serum 25(OH)D3 is between 100 and 150 nmol/L. To acheive this by supplements requires ca 4000 IU pd or more for the obese and some indivduals. This amount is well within the known physiological maximum production rate in the skin exposed to whole-body summer sunlight (10 to 20,000 IU pd).

The authors also ignore evolution. The vitamin D receptor has a 500 million year evolutionary history, its first role being in regulating innate immunty, our first line of defence against microbes, and one which lyses coronavirus rendering them unviable, a trick that vaccines do not replicate. Innate immune defences are pan-specific.

D3 also acts on adaptive immunity to calm the cytokine storm, although this is unlikely to arise if innate defences are fully D3-primed.

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Re: Vitamin D and covid-19: ignorance of physiology and evolution - The BMJ

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

Science Reveals Why Tea Is Good for Your Heart – HealthDay News

TUESDAY, March 9, 2021 (HealthDay News) -- If a nice hot cup of tea sounds good to you, there's even more reason to enjoy one now. Scientists have gained new insight into how tea helps lower blood pressure, perhaps pointing the way to new types of blood pressure medications.

The researchers found that certain compounds in both black and green tea help relax blood vessels by activating ion channel proteins in the walls of blood vessels.

Two catechin-type flavonoid compounds (epicatechin gallate and epigallocatechin-3-gallate) each activate a specific type of ion channel protein named KCNQ5, which is found in the smooth muscle that lines blood vessels.

Previous research suggested that tea catechins activated KCNQ5, and this new University of California, Irvine (UCI), study confirms that.

People worldwide have about 2 billion cups of tea each day. And tea is second only to water in terms of the volume consumed globally, the researchers said in background notes.

Black tea is often mixed with milk. In laboratory tests, the UCI team found that the addition of milk to black tea prevented the beneficial KCNQ5-activating effects of tea.

However, 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," study co-author Geoffrey Abbott said in a university news release. He's a professor in the department of physiology and biophysics in the UCI School of Medicine.

Previous studies have shown that even when milk is added, tea retains its blood pressure-lowering benefits.

The new study also found that warming green tea to 35 degrees Celsius (95 degrees Fahrenheit) changes its chemical composition in a way that makes 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," Abbott said. "Thus, simply by drinking tea we activate its beneficial, antihypertensive properties."

The findings were published in the March issue of the journal Cellular Physiology and Biochemistry.

More information

The U.S. Centers for Disease Control and Prevention has more on preventing high blood pressure.

SOURCE: University of California, Irvine, news release, March 6, 2021

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Science Reveals Why Tea Is Good for Your Heart - HealthDay News

Physiology

International Women’s Day | Notable Maine women who’ve made their mark on the world – NewsCenterMaine.com WCSH-WLBZ

Mainers are tough. Maine women are tougher.

MAINE, USA This list is just a few Maine women whose start in our state enabled them to make their mark on the world. And the list barely scratches the surface.

From politicians to Olympians, and astronauts to actors, these are just some of Maine's remarkable women.

Gov. Janet Mills

Janet Trafton Mills is an American politician and lawyer serving as the 75th governor of Maine since January 2019. She previously served as the Maine Attorney General on two occasions. Mills was both the state's first female governor and the first female attorney general.

Dr. Jessica Meir

Jessica Ulrika Meir is a Swedish-American NASA astronaut, marine biologist, and physiologist. The Caribou native was previously Assistant Professor of Anesthesia at Harvard Medical School, Massachusetts General Hospital, Boston, following postdoctoral research in comparative physiology at the University of British Columbia.

Last year, Meir spent 205 days in space aboard the International Space Station and made history by taking part in the first all-female spacewalk with Dr. Christina Koch.

Sen. Susan Collins

Susan Margaret Collins is an American politician serving as the senior United States Senator from Maine since Olympia Snowe retired in 2013. A Republican, she has represented Maine in the Senate since 1997. Born in Caribou, Maine, Collins is a graduate of St. Lawrence University in Canton, New York.

Rep. Chellie Pingree

Chellie Marie Pingree is an American politician serving as the U.S. Representative for Maine's 1st Congressional District since 2009. Her district includes most of the southern part of the state, including Portland and Augusta.

Secretary of State Shenna Bellows

Shenna Bellows is an American politician who was sworn in as Maine's new Secretary of State this January. Bellows is Maines first female Secretary of State and the 50th person elected to the office. She previously served two terms in the Maine Senate from 2016-2020, and most recently worked as executive director of the Holocaust and Human Rights Center of Maine.

Joan Benoit Samuelson

Joan Benoit Samuelson is an American Senior Grand Masters marathon runner who was the first women's Olympic Games marathon champion, winning the Gold medal at the 1984 Summer Olympics in Los Angeles. She held the fastest time for an American woman at the Chicago Marathon for 32 years after winning the race in 1985.

Julia Clukey

Julia Clukey is an American luger who started competing in 2002. Her best Luge World Cup season finish was 12th in women's singles in 200708. Clukey's best finish at the FIL World Luge Championships was fifth in women's singles at Lake Placid in 2009.

Anna Kendrick

Anna Cooke Kendrick is an American actress and singer. She began her career as a child in theater productions. Her first starring role was in the 1998 Broadway musical High Society, for which she earned a nomination for the Tony Award for Best Featured Actress in a Musical.

Margaret Chase Smith

Margaret Madeline Chase Smith was an American politician. A member of the Republican Party, she served as a U.S Representative and a U.S. Senator from Maine. She was the first woman to serve in both houses of the United States Congress, and the first woman to represent Maine in either.

Frances Perkins

Boston, Mass., 1880 - 1965

While not native to Maine, Frances Perkins' family had deep roots in our state dating back to the early 1700s in Newcastle, Maine.

Frances Perkins was an American workers-rights advocate who served as the U.S. Secretary of Labor from 1933 to 1945, the longest-serving in that position.

Again, this list only barely scratches the surface of the amazing feats of Maine women. NEWS CENTER Maine covers the stories of so many amazing Maine women every single day.

Especially today, please be sure to tell the important women in your life they're appreciated.

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International Women's Day | Notable Maine women who've made their mark on the world - NewsCenterMaine.com WCSH-WLBZ

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...