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The DNA of ancient Canaanites lives on in modern-day Lebanese, genetic analysis shows – Los Angeles Times

The Canaanites lived at the crossroads of the ancient world. They experienced wars, conquests and occupations for millennia, and as a result evolutionary geneticists expected that their DNA would become substantially mixed with incoming populations.

Astonishingly, new genetic analysis shows that scientists were wrong. According to a new study in the American Journal of Human Genetics, todays Lebanese share a whopping 93% of their DNA with the ancient Canaanites.

The study also found that the Bronze Age inhabitants of Sidon, a major Canaanite city-state in modern-day Lebanon, have the same genetic profile as people living 300 to 800 years earlier in present-day Jordan.

Later known as Phoenicians, the Canaanites have a murky past. Nearly all of their own records have been destroyed over the centuries, so their history has been mostly pieced together from archaeological records and the writings of other ancient peoples.

Archaeologists at the Sidon excavation site have been unearthing ancient Canaanite secrets for the last 19 years in the still-inhabited Lebanese port city. The team has uncovered 160 burials from the Canaanite period alone, said Claude Doumet-Serhal, director of the excavation. They have found people of all ages in these Canaanite burials, she said children were buried in jars and adults were placed in sand.

Claude Doumet-Serhal / The Sidon Excavation

An aerial view of the Sidon excavation site.

An aerial view of the Sidon excavation site. (Claude Doumet-Serhal / The Sidon Excavation)

Aided by new DNA sampling techniques, a team of evolutionary geneticists including Marc Haber and Chris Tyler-Smith from the Wellcome Trust Sanger Institute stepped in.

They sequenced the whole genomes of five individuals found in Sidon who lived about 3,700 years ago. The team then compared the genomes of these ancient Canaanites with those of 99 Lebanese people currently living in the country, along with the previously published genetic information from modern and ancient populations across Europe and Asia.

First, they investigated the genetic ancestry of the Canaanites themselves. They found that these Bronze Age inhabitants of Sidon shared about half their DNA with local Neolithic peoples and the other half with Chalcolithic Iranians. Interestingly, this genetic profile is nearly identical to the one evolutionary geneticist Iosif Lazaridis and his team found last year in Bronze Age villagers near Ain Ghazal in modern-day Jordan.

This suggests that Canaanite-related ancestry was spread across a wide region during the Bronze Age and was shared between urban societies on the coast and farming societies further inland. This evidence supports the idea that different Levantine cultural groups such as the Moabites, Israelites, and Phoenicians may have had a common genetic background, the authors said.

The researchers were also able to determine that the genetic mixing of the Levantine and Iranian peoples happened between 6,600 and 3,550 years ago, a range they would be able to narrow down with more ancient DNA samples from the region.

Claude Doumet-Serhal / The Sidon Excavation

The buried remains of a Canaanite adult whose DNA was sequenced in the study.

The buried remains of a Canaanite adult whose DNA was sequenced in the study. (Claude Doumet-Serhal / The Sidon Excavation)

Next, the team wanted to compare the Canaanite genome with the genetic makeup of the people who currently inhabit the ancient Canaanite cities. To do this, they collected DNA from 99 Lebanese people Druze, Muslim, and Christian alike.

As expected, they found some new additions to the modern Lebanese genome since the Bronze Age. About 7% of modern Lebanese DNA originates from eastern Steppe peoples found in what is now Russia, but wasnt represented in the Bronze Age Canaanites or their ancestors. What surprised the team was what was missing from their genetic data.

If you look at the history of Lebanon after the Bronze Age, especially it had a lot of conquests, Haber said. He and Tyler-Smith expected to see greater genetic contributions from multiple conquering peoples, and were surprised that as much as 93% of the Lebanese genome is shared with their Canaanite predecessors.

Though a 7% genetic influx from the Steppe seems very small, that number might be covering some hidden complexities, said Lazaridis, who worked on the Bronze Age Jordanian samples but was not involved in the new study.

Not much is known about the migrations of these eastern Steppe populations, he said. If the genomes of the incoming people were only half Steppe, for example, 14% of the Lebanese genome could have come from the new migrants.

Haber and Tyler-Smith said they want to explore this complexity further. Who were those eastern migrants? Where did they come from? And why did they migrate toward the Levant region? Haber asked. Analyzing more samples from different locations and periods could lead to an answer.

The team also wanted to know if the individuals from Sidon are more similar to modern-day Lebanese than to other modern Eurasian populations.

Despite small genetic variations between the three religious groups caused by preferential mating over time, the Lebanese genome is not widely varied. As a whole, the Lebanese people have more genetic overlap with the Canaanites from Sidon than do other modern Middle Eastern populations such as Jordanians, Syrians or Palestinians.

The difference is small, but its possible that the Lebanese population has remained more isolated over time from an influx of African DNA than other Levantine peoples, Lazaridis suggested.

Claude Doumet-Serhal - The Sidon Excavation

An archaeologist sorts pottery at the Sidon excavation site.

An archaeologist sorts pottery at the Sidon excavation site. (Claude Doumet-Serhal - The Sidon Excavation)

The findings have powerful cultural implications, Doumet-Serhal said. In a country struggling with the ramifications of war and a society fiercely divided along political and sectarian lines, religious groups have often looked to an uncertain history for their identities.

When Lebanon started in 1929, Doumet-Serhal said, the Christians said, We are Phoenician. The Muslims didnt accept that and they said, No, we are Arab.

But from this work comes a message of unity. We all belong to the same people, Doumet-Serhal said. We have always had a difficult past but we have a shared heritage we have to preserve.

mira.abed@latimes.com

Twitter: @mirakatherine

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The DNA of ancient Canaanites lives on in modern-day Lebanese, genetic analysis shows - Los Angeles Times

NSF issues awards to advance a national research infrastructure for … – National Science Foundation (press release)

News Release 17-069

NeuroNex projects will develop new tools, partnerships to understand the brain

August 1, 2017

The National Science Foundation (NSF) has made 17 Next Generation Networks for Neuroscience (NeuroNex) awards to aid the research community as it pursues one of its grandest challenges: understanding the brain.

These projects will support the development of innovative, accessible and shared capabilities and resources, as well as theoretical frameworks and computational modeling to advance neuroscience research.

NSF's NeuroNex awards will bring together researchers across disciplines with new technologies and approaches, yielding novel ways to tackle the mysteries of the brain. Befitting its multidisciplinary approach to research, the NeuroNex program involves participation from multiple NSF directorates. The overall goal of this activity is to establish a coherent national infrastructure to enhance our understanding of brain function across organizational levels and a diversity of species.

"Through the development of advanced instrumentation to observe and model the brain, we're closer to our goal of building a more complete knowledge base about how neural activity produces behavior," said Jim Olds, NSF assistant director for Biological Sciences. "NeuroNex seeks to take that progress forward, by creating an ecosystem of new tools, resources, and theories. Most importantly, NeuroNex aims to ensure their broad dissemination to the neuroscience community. With these awards, NSF is building a foundation for the next generation of research into the brain."

NeuroNex is one element of Understanding the Brain, NSF's multi-year effort to enable a scientific understanding of the full complexity of the brain. Through Understanding the Brain, NSF participates in the national Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative, an alliance of federal agencies and other partners seeking to enhance our understanding of the brain.

Nine of the new awards are for NeuroNex Neurotechnology Hubs, which will focus on the development, refinement and dissemination of innovative neurotechnologies. These hubs will provide:

Two of the awards are for NeuroNex Theory Teams, which will advance theoretical and computational frameworks for understanding the brain. Both of the awarded teams will focus on developing novel conceptual tools to decipher how the structure and dynamics of neurons give rise to behavior. The teams will work in concert with the Neurotechnology Hubs. Each of these eleven awards is for up to $2 million per year, for up to five years.

In addition, NSF issued six smaller NeuroNex Innovation awards, focused on developing potentially revolutionary, early-stage tools that can be integrated with other NeuroNex projects. All NeuroNex awards will also support workforce training opportunities. The complementary nature of the technologies and the mutual synergies between the technologies and the theories hold the promise of ushering in new ways of conducting neuroscience research.

The award titles, principal investigators and sponsor institutions are listed below.

NeuroNex Neurotechnology Hub awards:

NeuroNex Theory Teams awards:

NeuroNex Innovation awards:

-NSF-

Media Contacts Sarah Bates, NSF, (703) 292-7738, sabates@nsf.gov Rob Margetta, NSF, (703) 292-2663, rmargett@nsf.gov

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2017, its budget is $7.5 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives more than 48,000 competitive proposals for funding and makes about 12,000 new funding awards.

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Useful NSF Web Sites:NSF Home Page: https://www.nsf.govNSF News: https://www.nsf.gov/news/For the News Media: https://www.nsf.gov/news/newsroom.jspScience and Engineering Statistics: https://www.nsf.gov/statistics/Awards Searches: https://www.nsf.gov/awardsearch/

Blood cell reconstructions from University of Texas at Austin researcher Kristen M. Harris.Credit and Larger Version

Cornell University's Chris Xu studies how brains produce behavior in a range of species.Credit and Larger Version

Image from the lab of Spencer Smith, who will study next-generation multiphoton neuroimaging.Credit and Larger Version

Karl Deisseroth, professor of bioengineering, in his lab at Stanford University.Credit and Larger Version

An abstract 3-D model of connected neurons, sculpted by neuroscientist Xaq Pitkow.Credit and Larger Version

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NSF issues awards to advance a national research infrastructure for ... - National Science Foundation (press release)

College Notes – Times Herald-Record

College Notes appear on a space-available basis. To submit an announcement, email to communities@th-record.com. Put College Notes in the subject line. Announcements can also be mailed to College Notes, Times Herald-Record, P.O. Box 2046, Middletown 10940.

Michael S. Rallo, son of Melissa and Jack Rallo of Chester, graduated summa cum laude from Rutgers University in New Brunswick, N.J., with a Bachelor of Science in Cell Biology and Neuroscience and Exercise Science and Sport Studies. He was named to the dean's list all four years. Rallo will be continuing his education in the MD/PhD program at Rutgers Robert Wood Johnson Medical School and Princeton University.

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College Notes - Times Herald-Record

Geckos rapidly evolve bigger heads in response to human activity – New Atlas

Life is adept at adapting to changes in the environment and the environment is changing faster than ever, thanks to us. Evolution is normally thought of on the scale of millions of years, but a new study has observed how human activity has directly driven separate populations of geckos to evolve new attributes in the space of just 15 years.

The human activity in question began in 1996, with the building of the Serra da Mesa Hydroelectric Plant in Brazil. An artificial reservoir was created by flooding 656 sq mi (1,700 sq km), and in the process almost 300 new islands were now cut off from the "mainland."

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Researchers from the University of Brasilia and the University of California, Davis studied the newly-separated populations of animals on these islands, focusing on the most common gecko species in the area, Gymnodactylus amarali. The team found that over 15 years, G. amarali on the islands had grown bigger heads on average than those of the same species found on the mainland.

Before the dam was built, the geckos in the area had lived mostly off termites, with larger lizard species eating the bigger bugs and leaving the smaller ones to G. amarali. But it turns out that flooding the valley had wiped out those larger lizards, and with less inter-species competition for food, G. amarali adapted to fill the niche they left behind. The geckos grew larger mouths and heads to help them chow down on the newfound bounty of bigger termites.

It's a great "Petri dish" example of natural selection at work. Essentially, those G. amarali with bigger heads had access to more food, leading to them being more successful at survival and reproduction. Over time, the big-head genes were passed down to later generations in higher numbers, until it became a common characteristic of the island-dwelling geckos. Those still on the mainland, meanwhile, still faced competition from the larger lizards and so saw no change in head size, making them a perfect control group.

While their heads grew, the lizards' bodies stayed more or less the same size. The researchers say this is most likely a matter of efficiency: bigger bodies require more energy to run, which would offset the advantage of a larger head. And as further evidence that a bigger head relative to body size was the most efficient evolutionary path, the researchers found that the trait independently became common among populations on five islands isolated from each other.

The story of G. amarali isn't necessarily a sad one, but it does highlight just how much influence human behavior has on the environment, both directly and indirectly.

The research was published in the journal PNAS.

Source: Keele University via The Conversation

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Geckos rapidly evolve bigger heads in response to human activity - New Atlas

The path of the solar eclipse is already altering real-world behavior – Washington Post

The upcoming solar eclipse is poised to become the most photographed, most shared, most tweeted event in human history, in the words of one astronomer.Millions of people will watchit, potentially overwhelming the cities and towns along the eclipse's path of totality.

According to Google, interest in the eclipse has exploded nationwide in the past few months, mirroring national media attention. The county-level search data above, provided by Google, paints a striking picture: Interest in the eclipse is concentrated in the path of totality that cuts through the middle of the country, recedingsharplythe farther you go from that path.

The searches arean uncanny virtual reflection of the eclipse itself. Experts say the difference between a total eclipse (viewable only in the path of totality) and a partial one (everywhere else) is quite literally the difference between night and day. Web users in counties within the path of the totality arelooking up information on the eclipse five to 10 times more often than those well outside, according to Google's data.

In the past week, interest was highest in rural Clark County, Idaho, which lies directly in the eclipse's path. Nearby Idaho Falls plans to hold a four-day outdoor country music festivalit's calling Moonfest.

[Q&A: Do you have a question about the total solar eclipse coming in August?]

Nebraska's Pawnee and Banner counties, situated at opposite ends of the state, show the next-highest amount of interest. Banner county lies just outside the path of totality, while Pawnee is directly within it.

Rounding out the top five counties are Rabun and Towns counties in northeast Georgia, both squarely within the eclipse's path.

In the past week, people searching the Web forthe eventare mostly looking up basic facts a map of the eclipse's path, its exact time and information on the special glasses you'll need to avoid burning your eyeballs while looking at it.

The physical world asserts itself in our virtual lives in myriad ways. Searches for seasonal affective disorder follow a north-south gradient, for instance, and you can use Google searches to track everything from flu season to mosquito hatchings.

The eclipse searches are perhaps the most striking example of this phenomenon yet, as millions of Americans along an invisible celestial pathtap their keyboards together, unknown to one another.

Capital Weather Gang's Angela Fritz breaks down what will happen when a total solar eclipse crosses the U.S. on Aug. 21. (Claritza Jimenez,Daron Taylor,Angela Fritz/The Washington Post)

[A total solar eclipse is happening Aug. 21, and heres what you need to know]

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The path of the solar eclipse is already altering real-world behavior - Washington Post

Outstanding Leaders Exhibit More Than Just Emotional Intelligence–They Have These 7 Traits, According to … – Inc.com

The topic of emotional intelligence (EQ) continues to dominate leadership conversations. Rightly so. However, in a Harvard Business Review (HBR) article that highlighted research by Daniel Goleman and Richard Boyatzis (experts on the topic), EQ is only the beginning.

Whereas EQ has an emphasis on individual psychology, there is a more relationship-based version called social intelligence. Social Intelligence, as defined by Goleman and Boyatizis, is a set of interpersonal competencies built on specific neural circuits and responses that inspire others to be effective. In other words, based on neuroscience and biology, there are certain leadership behaviors that elicit positive emotional responses in your team members.

Although there are a few, one important neurological discovery that supports the importance of social intelligence are "mirror neurons." In short, a mirror neuron fires in social situations telling our brains to mimic, or "mirror," what someone else does. That's why you might find yourself copying people's body language or drawing off of other's energy. As you can imagine, this research has extraordinary significance in organizations especially for those in a position to influence others.

To ensure that you set the right tone. Here seven traits, from the same HBR article, to gauge your social intelligence and ensure that you're leading by example:

Great leaders are cognizant and receptive of others' needs, backgrounds, and motivators. They listen objectively and make sure not to pass any preconceived judgments. They are understanding and use compassion to relate to employees and then redirect them down the right path.

Socially adept managers actively listen to others and consider their feelings. They tune into their employees' frequencies and adjust to their approach to match their communications style, therefore, maximizing their effectiveness.

Leaders with a high social quotient appreciate the importance of values and advocate for them across their team/organization. They recognize unspoken norms and adjust their styles to fit within the company's culture.

This refers to a manager's ability to motivate and persuade others. When leveraging social intelligence, a manager can uncover and appeal to their staff's self-interest. They can learn what makes them tick and find ways to incorporate their passions into their responsibilities.

In the words of Kevin Spacey, "If you're lucky enough to do well, it's your responsibility to send the elevator back down." Emotionally and socially mature leaders coach and mentor others with kindness. They realize the need and willingly take others under their wing.

Managers who are emotionally and socially mindful are able to articulate a compelling vision that builds group pride while simultaneously bringing out the best in people. They are able to explain why work matters and directly connect individual and team passions with organizational goals.

The socially intelligent understand the importance of team cooperation as a means to form bonds and increase morale. They appreciate the team's dynamics and ensure that everyone has an opportunity to provide input.

Although these seven traits don't seem measurable, Goleman and Boyatzis's research showed a large performance gap between socially intelligent and socially unintelligent leaders. If you feel like you've exhausted all other options to maximize your team's performance, then redirect the focus to yourself and develop these vital leadership attributes.

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Outstanding Leaders Exhibit More Than Just Emotional Intelligence--They Have These 7 Traits, According to ... - Inc.com

IRICoR announces the appointment of Dr. Martin Godbout as Chairman of its Board of Directors and of Ms. Catherine … – Markets Insider

MONTREAL, July 31, 2017 /CNW Telbec/ - IRICoR (Institute for Research in Immunology and Cancer - Commercialization of Research) proudly announces the appointment of Dr. Martin Godbout, president of Hodran Consultants Inc., as the new Chairman of its Board of Directors and of Ms. Catherine Bouchard, Head of Research, Life Sciences at the Caisse de dpt et placement du Qubec, as a new Board member.

Dr. Godbout brings to IRICoR's Board a deep expertise in the health sciences sector. With his thorough knowledge of the field and his close to 30-year experience, he will greatly contribute to IRICoR's ongoing initiatives to attract and accelerate the development of promising innovative projects in oncology. Dr. Godbout started his professional career as President and CEO of Socit Innovatech Qubec, a technology-focused venture capital (VC) fund. He then served as Executive Vice-president of BioCapital, a biopharmaceutical VC firm, after which he founded Genome Canada, which he successfully led for more than 10 years as CEO. He was also a Board member of numerous biopharmaceutical companies, not-for-profit organizations involved in funding research and innovation and philanthropic organizations. He is currently Chair of the Board at Amorchem-I, BioContact, BioQubec and Genome Quebec, and a Board Member of various organizations, including the Fonds de recherche du Qubec Sant. Dr. Godbout holds a B.Sc. in Biochemistry and a Ph.D. in Physiology and Molecular Endocrinology from Universit Laval. He completed his post-doctoral training in Molecular Neurobiology at San Diego'sScripps Research Institute. Finally, Dr. Godbout is an Officer at the Order of Canada.

"We enthusiastically welcome Dr. Godbout to IRICoR's team. His diverse professional expertise both in the healthcare and business sectors, as well as his broad professional network will be critical to the success of IRICoR's ongoing strategic initiatives."Nadine Beauger, Chief Executive Officer - IRICoR

Dr. Godbout succeeds Johane Boucher-Champagne who was Chair of IRICoR's Board since 2011, after having been a member since 2009. IRICoR takes this opportunity to formally thank Mrs. Boucher-Champagne for having put her deep experience in the life science sector to the service of IRICoR. She has truly been a key resource for the organization through all those years.

"Through her deep knowledge of the pharmaceutical sector and her keen governance skills, Mrs. Boucher-Champagne skillfully managed to further IRICoR's initiatives, leading the organization to become a leader in commercialization of research. We are very grateful for Mrs. Boucher-Champagne's 8 years of continuous commitment."Michel Bouvier, Chief Executive Officer and Principal Investigator, IRIC (Institute for Research in Immunology and Cancer)

Catherine Bouchard has more than 10 years of experience in healthcare equity research. She is currently Head of Research, Life Sciences at the Caisse de dpt et placement du Qubec, where she has served as Senior Healthcare Analyst since 2012. Prior to joining CDPQ, Ms. Bouchard spent 5 years at Valeurs Mobilires Banque Laurentienne, where she was the Lead Analyst covering healthcare stocks. Her expertise in industry analysis and her deep knowledge of the healthcare sector will be key additions for IRICoR. She holds a B.Sc. in Microbiology and Immunology and an M.Sc. in Biomedical Sciences from Universit de Montral, as well as an MBA from HEC Montreal.

Dr. Godbout and Ms. Bouchard are joining a Board that stands out for its Members' deep commitment, diverse expertise in both health sciences and business matters, as well as its extended network.

About the Institute for Research in Immunology and Cancer Commercialization of Research (IRICoR)

As Universit de Montral's drug discovery and project maturation cluster, IRICoR is a not-for-profit organization based at the Institute for Research in Immunology and Cancer (IRIC), with the mandate to accelerate the discovery, development and commercialization of novel therapies in cancer, immunotherapy and related fields. Since its creation in 2008, IRICoR successfully invests in and supports cutting-edge projects with disruptive potential to rapidly translate innovation into patient-accessible therapies, through either co-development partnerships with industry or company creation. IRICoR seamlessly integrates business-related expertise with industry-level drug discovery in a world-renowned research institute, providing academics with access to a full drug discovery chain with one of the largest academia-based medicinal chemistry groups in Canada. For more information about IRICoR: http://www.iricor.ca

About the Institute for Research in Immunology and Cancer (IRIC)

An ultra-modern research hub and training centre located in the heart of the Universit de Montreal, the Institute for Research in Immunology and Cancer (IRIC) was created in 2003 to shed light on the mechanisms of cancer and discover new, more effective therapies to counter this disease. IRIC operates according to a model that is unique in Canada. Its innovative approach to research has already led to discoveries that will, over the coming years, have a significant impact on the fight against cancer. For further information visit http://www.iric.ca

About the University of Montreal

Deeply rooted in Montreal and dedicated to its international mission, the University of Montreal is one of the top 100 universities in the world. It was founded in 1878, and together with its two affiliated schools, HEC Montral and Polytechnique Montral, constitutes the largest centre of higher education and research in Quebec and one of the major centres in North America. The University of Montreal brings together more than 2,700 professors and researchers and welcomes more than 68,000 students. http://www.umontreal.ca

SOURCE Institut de recherche en immunologie et en cancrologie de l'Universit de Montral

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IRICoR announces the appointment of Dr. Martin Godbout as Chairman of its Board of Directors and of Ms. Catherine ... - Markets Insider

Anatomy and physiology of ageing 7: the endocrine system – Nursing Times

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John Knight is senior lecturer in biomedical science; Yamni Nigam is associate professor in biomedical science; both at the College of Human Healthand Science, Swansea University.

Glands in the endocrine system produce a range of hormones that regulate our bodys activities by keeping substances such as blood glucose and electrolytes within their normal ranges. Like all other body systems, the endocrine system undergoes age-related changes that negatively affect its functioning. As a result of these changes, older people are more prone to disturbed sleep patterns, have a reduced metabolic rate, lose bone density, accumulate body fat, and show increases in blood glucose. As a consequence, they are at higher risk of health issues such as insomnia, fractures, type 2 diabetes and cognitive decline. This seventh article in our series about the effects of age on the body describes what happens, with advancing age, to endocrine glands and hormone production.

Knight J, Nigam Y (2017) Anatomy and physiology of ageing 7:the endocrine system. Nursing Times [online]; 113: 8, 48-51

The endocrine system works in conjunction with the nervous system to regulate, and coordinate the activities of, the bodys tissues and organs. It consists of a collection of glands located in different parts of the body the main ones being the pituitary, pineal, thyroid, parathyroids, adrenals, pancreas, ovaries and testes (Fig 1). These glands produce a variety of blood-borne chemical signals called hormones, which play an essential role in maintaining balance (homoeostasis) in the body, helping to ensure that variables such as blood glucose and electrolytes are kept within normal ranges.

fig 1 the effects of ageing on endocrine function

The pituitary gland, often referred to as the master gland, produces several major hormones and regulates the activity of many other endocrine glands. It is split into a posterior portion, which is formed from neural tissue extending from the hypothalamus, and an anterior portion, which is formed from epithelial cells derived from the roof of the oral cavity.

The anterior pituitary secretes growth hormone (somatotropin), which promotes the growth of bone, muscle and most of the major internal organs. In early childhood, somatotropin is secreted in relatively small amounts, but during the teenage years there is a marked increase in serum somatotropin levels corresponding to the growth spurts of puberty. Around the age of 25-30, somatotropin secretion begins to decline in both men and women. In men it is estimated to halve every seven years although there appears to be much variation between individuals (Gentili, 2015).

The decline in somatotropin secretion in later years is often referred to as the somatopause and is associated with a variety of physiological changes (Jonas et al, 2015; Veldhuis et al, 2005), including:

The somatopause can be hastened in people who lead a sedentary lifestyle and in those who already carry a high percentage of body fat. Conversely, in premeno-pausal women, oestrogen appears to slow its onset and progression (Gentili, 2015).

The exact causes of somatopause are yet to be fully established, however, the age-related decrease in somatotropin secretion mirrors the decrease of growth-hormone releasing hormone (GHRH) secretion by the hypothalamus. Recent research indicates that some of the negative physiological changes that come with declining levels of somatotropin can be reversed by growth hormone replacement therapy. In clinical trials, recombinant human growth hormone has been shown to improve lean muscle mass retention and quality of life scores in older people (Jonas et al, 2015).

The pineal gland is slightly smaller than a pea and resembles a small pine cone hence its name. Found in the diencephalon, towards the centre of the brain, it synthesises the hormone melatonin from the neurotransmitter serotonin. The pineal gland functions like an internal body clock: during the day, when there is a lot of light, melatonin secretion is inhibited, but as the day draws to a close and light diminishes, melatonin secretion increases, preparing the body for sleep.

As we age, the pineal gland undergoes a process of calcification, detectable even in young children. Melatonin levels progressively decrease: 60-year-olds have 80% less melatonin in their blood than teenagers. Some drugs commonly prescribed to older people, such as beta blockers and non-steroidal anti-inflammatory drugs, can reduce melatonin levels even further.

Decreased melatonin levels are linked to an increased prevalence of sleep disturbances and, in some people, may ultimately lead to geriatric insomnia (Bubenik and Konturek, 2011). Since sleep is essential for cognitive function, sleep disturbances can exacerbate age-related changes in the brain.

There is some evidence that exposure to bright light either sunlight or artificial light in the morning increases the speed of sleep onset by triggering an earlier release of melatonin in the evening. Similarly, the therapeutic use of prolonged-release melatonin has been shown to improve sleep onset time, sleep quality, morning alertness and quality of life in people aged 55 and over who have insomnia (Wade et al, 2007)

The thyroid gland plays a major role in controlling metabolism and adjusting blood calcium levels. The hormones it secretes regulate a number of physiological processes, including:

The thyroid secretes the iodine-containing hormones T4 (tetraiodothyronine, which is also known as thyroxine) and T3 (triiodothyronine), which largely control cellular metabolism. T4 is released in greater quantities than T3, the typical ratio being 15:1. T4 is then rapidly converted into the more biologically active T3, which is around three times more potent in terms of increasing the metabolic rate.

The clearance of T4 by the liver decreases with age, but this is offset by a gradual decline in T4 secretion, so T4 serum levels tend to remain constant. However, there is a clear age-related decrease in the levels of serum T3, as well as of thyroid-stimulating hormone (TSH) produced by the pituitary gland (Peeters, 2008; Chahal and Drake, 2007). This may contribute to the gradual reduction in basal metabolism that is apparent in many people in middle and old age (in which the decline in lean muscle mass described above also plays a role).

With advancing age, autoimmune reactions against ones own thyroid gland are commonly seen. Indeed, the presence, in older people, of antibodies specific to thyroid tissue is so common that it is often considered a normal age-related change. A high concentration of such antibodies may herald the onset of autoimmune hypothyroidism, a disease affecting up to 5% of the over-60s and associated with low metabolic rates, a tendency to put on weight and low core temperature. Since this condition is autoimmune in nature, women are at greater risk of developing it (this is true for most autoimmune diseases): up to eight times more women than men experience autoimmune hypothyroidism.

The results of thyroid function tests should be assessed carefully in older people, as common long-term conditions (such as chronic obstructive pulmonary disease, hypertension, diabetes and arthritis) and dieting can lead to reductions in circulating thyroid hormones, particularly the more active T3. This phenomenon of reduced thyroid function in the absence of thyroid disease is referred to as non-thyroidal illness. Similarly, many drugs used to treat long-term conditions in older people (for example, lithium and glucocorticoids) can supress thyroid function or reduce the activity of circulating thyroid hormones, leading to a reduction in metabolic rate (Peeters, 2008).

The thyroid gland also plays a role in calcium homoeostasis. When we consume foods rich in calcium, it releases calcitonin, which inhibits the activity of osteoclasts bone cells that break down bone tissue (bone is a dynamic tissue continually being built and broken down). By inhibiting osteoclast activity, calcitonin indirectly increases bone density.

Few studies have examined the effects of ageing on calcitonin production in humans. The most comprehensive study, dating back to 1980, demonstrated an age-related decline in calcitonin production in 50 healthy women aged between 20 and 69 years (Shamonki et al, 1980). This decline may partially explain the reduction in bone mass seen in most women as they grow older. However, a later study has contradicted these findings, showing that although women appear to have lower levels of calcitonin secretion than men, there is no clear age-related decrease in serum calcitonin concentration (Tiegs et al, 1986).

The posterior portion of the thyroid is the location of four tiny parathyroid glands, which secrete parathyroid hormone (PTH) whenever blood calcium levels fall. Since a normal concentration of calcium is essential to many physiological processes (including muscle contraction, nerve conduction and blood clotting), the reserves of calcium stored in the skeleton need to be mobilised. PTH triggersthe release of calcium from the bonesinto the blood by indirectly stimulating osteoclasts.

Several studies have shown that most people, as they grow older, have significantly increased levels of circulating PTH (Portale et al, 1997). This hyperparathyroidism may well be one of the main causes of the reduction in bone density commonly seen in middle and old age. Recent studies have also shown a potential link with other pathologies, particularly age-related cognitive decline and dementia (Braverman et al, 2009).

The endocrine regions of the pancreas (islets of Langerhans) regulate bloodglucose levels. Beta cells in the islets secrete insulin in response to increased blood glucose for example, after a carbohydrate-rich meal. Insulin binds to receptors present on most cells, triggering the uptake of glucose from the blood. Once inside the cells, glucose is either metabolised immediately to release energy, or stored and converted into glycogen.

Alongside race, genetic predisposition and a high body mass index, ageing is one of the many risk factors linked to the development of type 2 diabetes (Knight and Nigam, 2017). Ageing human cells become less sensitive to the effects of insulin. The most likely cause appears to be a reduction in the number of insulin receptors at the surface of cells. This gradual insulin resistance goes hand in hand with an increase in blood glucose concentrations.

As shown in a study of 6,901 non-diabetic people (Ko et al, 2006), fasting blood glucose levels rise by around 0.15mmol/L for each decade of life after the age of 20. Whether this rise is a normal age-related change or a sign of diabetes in its early stages is not always clear, but it is certainly seen in many older people with no other symptoms of diabetes.

With advancing age, the insulin-producing beta cells become less sensitive to the level of glucose in the blood, so higher blood glucose levels are needed to trigger insulin release. Since older peoples cells are less receptive to insulin, the pancreas often responds by producing more, leading to increased insulin levels in the blood (hyperinsulinaemia). This can put excessive stress on the beta cells, leading to their exhaustion.

Age-related depletion of the beta cell population in the pancreas also occurs as a result of increased programmed cell death (apoptosis) and a diminished ability of the pancreas to produce new cells. Beta cell exhaustion and depletion result in a drop of insulin secretion of up to 0.5% per year of life. Additionally, the clearance of insulin by the liver increases with age, so there is less insulin available to interact with cells and promote glucose uptake.

These age-related changes to insulin production, clearance and response contribute to the creation of a diabetogenic environment. This may partially explain why the risk of developing type 2 diabetes increases with age (Brown, 2012).

The accumulation of abdominal fat is a common feature of ageing, particularly in people who have a poor diet and/or a sedentary lifestyle. Many age-related changes to the endocrine system contribute to this accumulation of adipose tissue, including the somatopause, autoimmune hypothyroidism, insulin resistance, and reduced circulating sex hormones.

This abdominal fat accumulation is linked to heart disease, high blood pressure and type 2 diabetes. These conditions may occur in isolation or together in the form of metabolic syndrome (Gong and Muzumdar, 2012).

The two adrenal glands are located above the kidneys and each consists of two main regions: the adrenal medulla (inner region) and the adrenal cortex (outermost layer).

The adrenal medulla is the location of chomaffin cells, which secrete the catecholamines adrenaline (epinephrine) and noradrenaline (norepinephrine). These are the fight or flight hormones that prepare the body for activity when it is threatened or in a state of excitement. The effects of adrenaline and nor-adrenaline include:

Ageing is associated with a decline in the secretion of adrenaline, but adrenaline plasma levels remain relatively constant

as clearance by the kidneys is usually reduced. There is some evidence that older men secrete less adrenaline in response to acute stress than younger men (Seals and Esler, 2000).

The adrenal cortex synthesises a varietyof steroidal hormones from cholesterol, mainly aldosterone and cortisol.

Aldosterone is a mineralocorticoid that regulates plasma levels of sodium and potassium, and plays an important role in water balance and blood pressure control. Research has revealed an age-related decrease in serum aldosterone levels, effectively reducing the bodys ability to retain sodium.

Decreased aldosterone secretion may contribute to postural hypotension and the light-headedness that is often experienced by older people when they stand up. This is supported by research demonstrating significant reductions in serum aldosterone levels in older people when they are upright, as opposed to recumbent (Hegstad et al, 1983).

Since sodium attracts water into the cardiovascular system via osmosis, lower plasma sodium levels (hyponatraemia) can lead to reduced blood volume and blood pressure. Several medications commonly prescribed to older people such as opiates, non-steroidal anti-inflammatory drugs, diuretics and antidepressants can exacerbate hyponatraemia (Liamis et al, 2008). Blood volume and blood pressure may be further reduced by age-related increases in the secretion of atrial natriuretic hormone (ANH), a powerful diuretic produced by the heart (Miller, 2009).

Cortisol is a glucocorticoid and its release is triggered by biological stressors such as physical injury or starvation. It is a natural anti-inflammatory and plays an important role in the breakdown of protein and fat.

Research into how cortisol levels change with ageing is often contradictory. Initial studies suggested that there could be a 20-50% increase in the mean levels of cortisol secretion between the ages of 20 and 80 (Chahal and Drake, 2007). More recently, however, it has been shown that this is not necessarily true: in some people, cortisol secretion diminishes with age, in others levels remain relatively stable throughout life (Wolf, 2015).

There appears to be a link between increased cortisol levels, reduced bone density and increased risk of bone fracture. There is also growing evidence that a higher cortisol concentration can contribute to the loss of cells from the hippocampus, resulting in hippocampal atrophy. This is often associated with a reduction in cognitive function in older people (Chahal and Drake, 2007). Other studies have shown that age-related increases in cortisol may also be linked to memory loss and sleep disorders (Chahal and Drake, 2007; Wolf et al, 2005).

There is some evidence that exercising regularly and maintaining a low percentage of body fat may slow the onset of the somatopause, help maintain bone density and improve the control of blood glucose. Supplementation with synthetic growth hormone has recently been shown to increase lean muscle mass in older people. However, this kind of therapy is associated with many side-effects such as joint pain, oedema and impaired glucose tolerance (Jonas et al, 2015).

The most famous and most thoroughly researched hormone replacement therapies are those that are used to treat the complications of the menopause. These therapies will be explored in the next article in this series.

Braverman ER et al (2009) Age-related increases in parathyroid hormone may be antecedent to both osteoporosis and dementia. BioMed Central Endocrine Disorders; 9: 21, 1-10.

Brown JE (2012) The ageing pancreas. British Journal of Diabetes and Vascular Disease; 12: 3, 141-145.

Bubenik GA, Konturek SJ (2011) Melatonin and aging: prospects for human treatment Journal of Physiology and Pharmacology; 62: 1, 13-19.

Chahal HS, Drake WM (2007) The endocrine system and ageing. Journal of Pathology; 211: 2, 173-180.

Gentili A (2015) Growth hormone replacement in older men. Medscape.

Gong Z, Muzumdar RH (2012) Pancreatic function, type 2 diabetes, and metabolism in aging. International Journal of Endocrinology; 2012: 320482.

Hegstad R et al (1983) Ageing and aldosterone. American Journal of Medicine; 74: 3, 442-448.

Jonas M et al (2015) Aging and the endocrine system. Postpy Nauk Medycznych; 28: 7, 451-457.

Knight J, Nigam Y (2017) Diabetes management 1: disease types, symptoms and diagnosis. Nursing Times; 113: 4, 40-44.

Ko GT et al (2006) Effects of age on plasma glucose levels in non-diabetic Hong Kong Chinese. Croatian Medical Journal; 47: 5, 709-713.

Liamis G et al (2008) A review of drug-induced hyponatremia. American Journal of Kidney Disease; 52: 1, 144-153.

Miller M (2009) Fluid balance disorders in the elderly. American Society of Nephrology online curricula: geriatric nephrology.

Peeters RP (2008) Thyroid hormones and aging. Hormones; 7: 1, 28-35.

Portale AA et al (1997) Aging alters calcium regulation of serum concentration of parathyroid hormone in healthy men. American Journal of Physiology; 272: 139-146.

Seals DR, Esler MD (2000) Human ageing and the sympathoadrenal system. Journal of Physiology; 528: 3, 407-417.

Shamonki IM et al (1980) Age-related changes of calcitonin secretion in females. Journal of Clinical Endocrinology and Metabolism; 50: 3, 437-439.

Tiegs RD et al (1986) Secretion and metabolism of monomeric human calcitonin: effects of age, sex, and thyroid damage. Journal of Bone and Mineral Research; 4: 339-349.

Veldhuis JD et al (2005) Joint mechanisms of impaired growth-hormone pulse renewal in aging men. Journal of Clinical Endocrinology and Metabolism; 9: 7, 4177-4183.

Wade AG et al (2007) Efficacy of prolonged release melatonin in insomnia patients aged 55-80 years: quality of sleep and next-day alertness outcomes. Current Medical Research and Opinion; 23: 10, 2597-2605.

Wolf OT (2015) Effects of Stress on Memory: Relevance for Human Aging. Encyclopedia of Geropsychology. Singapore: Springer Science.

Wolf OT et al (2005) Subjective memory complaints in aging are associated with elevated cortisol levels. Neurobiology of Aging; 26: 10, 1357-1363.

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Anatomy and physiology of ageing 7: the endocrine system - Nursing Times

Allahabad University scientists create ‘accelerated ageing model’ in … – Hindustan Times

Decoding aging is one complicated process that scientists across globe are busy working on.

While a revolutionary breakthrough is still awaited, a group of scientists from Allahabad have developed unique model of rat which can go a long way in helping them find a formula to control the process.

Perhaps taking a cue from Bollywood blockbuster Paa, the scientists have developed a model of rat which displays a higher rate of aging.

The accelerated aging model of rat provides a great tool for scientists to study aging and also to test anti-aging drugs, claims prof SI Rizvi from the Biochemistry department of Allahabad University (AU).

Rizvi is leading the research team.

The teams findings and achievement have been published in the recent issue of the prestigious research journal Biochemical and Biophysical Research Communications published from US.

Explaining his new research, prof Rizvi said that his team created a rat model which mimics the human condition of Progeria, a disease in which the patient starts to show a faster rate of aging.

Progeria syndrome was highlighted in the acclaimed Hindi movie Paa wherein the character was portrayed effectively by Amitabh Bachchan.

Progeria is a rare genetic condition that causes a childs body to age fast. Most kids with progeria do not live past the age of 13. The disease affects both sexes and all races equally. It affects about 1 in every 4 million births worldwide. Medical experts believe that India has around 8-10 reported cases of progeria and potentially 66 unreported cases.

To study aging, scientists rely on animal models such as C elegans (an earthworm), fruit flies, and mice. The consideration for choosing an animal is primarily based on its lifespan. Shorter lifespan provides an opportunity to study age-dependent changes in a shorter time frame.

To create the Progeria model of rat, the Allahabad University scientists subjected normal rats to chronic treatment of 30 days with dihydrotachysterol, a chemical similar to vitamin D. A look into relevant scientific literature reveals that very few studies have been conducted on such a model of rat.

Normal experimental rats have a lifespan of two years, which is too large a time for conducting experiments. The rat model mimicking Progeria provides a very good model to study aging process in a short span of time, added prof Rizvi.

The young progeria-mimicking rats display a certain level of oxidative stress (an established hallmark of aging) equivalent to old age rats.

The research group will now test Metformin, a common anti-diabetic drug, as an experimental anti-aging drug on increased aging model rats. Initial results using Metformin as an anti aging drug have been very exciting, added prof Rizvi.

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Allahabad University scientists create 'accelerated ageing model' in ... - Hindustan Times

Researchers describe structures, mechanisms that enable bacteria to resist antibiotics – Phys.Org

A ribbon diagram of the three-part efflux pump of the Campylobacter jejuni bacterium. Credit: Edward Yu/Iowa State University

Two new discoveries from Edward Yu's Iowa State University laboratory are adding to the scientific understanding of how bacteria resist antibiotics.

Yu and his research group have just described two structures and mechanisms - efflux pumps and reinforced cell walls - that certain disease-causing bacteria use to keep antibiotics away. That understanding could one day lead to new treatments that disable the structures and restore the effectiveness of drugs.

"We study a lot of efflux pumps to understand antibiotic resistance," said Yu, an Iowa State professor with appointments in physics and astronomy; chemistry; biochemistry, biophysics and molecular biology; and the U.S. Department of Energy's Ames Laboratory. "Cell wall remodeling is also a major mechanism to work against antibacterial drugs.

"The structure and mechanism depend on the bacteria you're talking about - and the bacteria will find a way."

Two journals have just published the latest findings by Yu's research group:

Previous studies reported the three molecules of the pump worked in a synchronized rotation - one molecule accessing, one molecule binding and one molecule extruding - to pump antibiotics from the cell. Yu's research group found that each part of the pump worked independently of the others, essentially creating three pumps in one structure.

"The three independent pumps make it a more powerful multidrug efflux pump," Yu said.

The paper focuses on how these bacteria transport hopanoid lipid compounds to their outer cell membranes. The compounds contribute to membrane stability and stiffness.

"Overall our data suggest a novel mechanism for hopanoid transport involved in cell wall remodeling, which is critical for mediating multidrug resistance in Burkholderia," the authors wrote in a project summary.

Grants from the National Institutes of Health supported both studies. Grants from the U.S. Department of Energy also supported ultra-bright, high-energy X-ray experiments at the Advanced Photon Source at Argonne National Laboratory in Illinois.

Yu and his research group have a long history of successfully using X-ray crystallography to describe and understand the structure of pumps, transporters and regulators in bacteria. A gallery on his research group's website shows ribbon diagrams of 21 different structures.

Because of Yu's significant contribution to the understanding of antimicrobial resistance in bacteria, the American Academy of Microbiology elected him to be an academy fellow earlier this year.

With that comprehensive understanding of the structures and mechanisms behind bacterial resistance to antibiotics, Yu said his research group is beginning to look at how the pumps and transporters can be turned off.

"We're trying to find an inhibitor compound," Yu said. "We're thinking about doing a little more translational science. We have a lot of rich information about the structure and function of these pumps. Why not use it?"

Explore further: Scientists describe protein pumps that allow bacteria to resist drugs

More information: Chih-Chia Su et al, Structures and transport dynamics of a Campylobacter jejuni multidrug efflux pump, Nature Communications (2017). DOI: 10.1038/s41467-017-00217-z

Nitin Kumar et al. Crystal structures of theBurkholderia multivoranshopanoid transporter HpnN, Proceedings of the National Academy of Sciences (2017). DOI: 10.1073/pnas.1619660114

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Researchers describe structures, mechanisms that enable bacteria to resist antibiotics - Phys.Org