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Chef leaves salmon to starving orcas

Chef leaves salmon to starving orcas

To save more chinook salmon for starving orcas, Seattle chef Renee Erickson has taken it off the menu.

Erickson, chef and co-owner of Sea Creatures, which includes Seattle restaurants The Walrus and the Carpenter and The Whale Wins, announced her decision recently to her newsletter subscribers and chefs.

It’s something she has been thinking about for a while. But it was the sight of Tahlequah, the mother orca whale carrying her dead calf for 17 days for more than 1,000 miles (1,609km) that pushed Erickson to no longer serve chinook to her customers.

“It’s sad; I love eating it, and I grew up catching it,” Erickson said. But with so many other local fish possibilities, it just felt wrong to take chinook out of orcas’ mouths, she said.

“The biggest gut wrench is that we have starving orcas. We are eating the salmon they need to eat.”

Southern resident killer whales, the orcas of the trans-boundary waters of the Salish Sea and West Coast, rely on chinook for more than 90% of their diet in the summer. The big, fatty fish are in decline in Puget Sound and the Fraser and Columbia Rivers. That depletes the food supply for orcas in their primary foraging areas.

Seeing the impact on the whales, declined to only 75 members in the J, K and L pods, just became too much, Erickson said.

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She said hers was a decision borne of personal reflection. “It’s nothing heroic,” she said, adding she is not launching a campaign for others to follow suit.

Though as a leading, James Beard-award-winning chef, Erickson’s influence has been felt before, including her refusal to serve farmed Atlantic salmon at her restaurants.

The southern residents face at least three struggles to survive: Too much noise in their home waters makes it harder for them to find food; toxins in their food; and lack of sufficient food add to their trouble.

“To see the effect we are having on these animals, it is too much,” said Erickson. To her, laying off chinook made sense, to leave more for the whales.

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Other salmon choices

With so many other good choices, from sockeye in season to local shellfish and coho, “we live so well”, Erickson said.

In an October scientific paper, Rob Williams, a marine-conservation biologist based at Oceans Initiative in Seattle, a nonprofit research firm, found with his co-authors that lack of food was the biggest threat to the southern resident’s survival. The whales have to have more food and less racket underwater to be able to hunt, the scientists concluded.

Williams, who works with northern and southern resident populations of orca whales, was the lead author on a paper published in PlosOne in November 2011 that found British Columbia salmon stocks in general are estimated to be at 36% of historical (1800s) run size, and Puget Sound stocks at 8%.

Because southern resident killer whales specialise in eating chinook, lack of it is linked to increased mortality and reduced reproduction.

Prey intake for a lactating female can also be more than 40% higher than when not lactating – so for successful reproduction, the southern residents need even more chinook.

Instead, runs continue to decline and the southern residents have not successfully reproduced in three years. The southern resident orcas’ annual need could be from 211,000 to 364,000 chinook, depending on the body size of the fish, Williams and other authors on the paper determined in their analysis.

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Renee Erickson, on her boat on a crabbing excursion near Shilshole Bay in Seattle, in August 2015. Photo: TNS

That’s enough to consider managing fish stocks with the whales’ consumption in mind, under an ecologically based management scheme – with more fish needed to boost the population to recovery, the scientists found.

One clear loser in whale recovery are the chinook themselves – and to recover populations of the fish that are also threatened with extinction, managers need to consider the needs of a recovering orca population – not just human fishermen, according to the scientists.

Williams said he thinks Erickson made a good decision.

“Chefs across America should think about this,” he said.

“If everyone was moved by the sight of J35 and her calf,” he said of Tahlequah, this is one thing you can do: Stop eating chinook.

“Don’t buy it, don’t eat it, don’t serve it,” Williams said of chinook.

“The whales need it more than we do.” – The Seattle Times/Tribune News Service/Lynda V. Mapes

‘Zombie gene’ in elephants prevents cancer

‘Zombie gene’ in elephants prevents cancer

Maybe it’s the elephant’s genes that never forget. In addition to having great memories, elephants are known for having a very low incidence of cancer.

In what might seem a wild mash-up of the SyFy channel and National Geographic, new research has uncovered a surprising factor that protects elephants against the dread disease: a gene that had gone dormant in their mammalian ancestors, but got turned back on as their evolving bodies grew ever bigger.

Scientists call it a “zombie gene” – cue the chilling music here – “a reanimated pseudogene that kills cells when expressed”.

The zombie gene is not just a curiosity.

Along with elephants, several kinds of whales, as well as bats and the naked mole rat, share enviably minuscule rates of cancer.

Biologists suspect that each of those species has evolved a different strategy to ward off malignancies, and they want to understand them all.

In time, they might find ways to approximate those strategies in humans and drive down our vulnerability to cancer.

“That’s not easy,” said Vincent J. Lynch, who led the research published in the journal Cell Reports.

Nor, he added, would it always be safe. After all, mechanisms that thwart fast-growing cells or turbocharge cellular-repair machinery have evolved over countless generations in fine balance with other checks and balances, he said.

Transfer one of these mechanisms willy-nilly to another species, and it would very likely run amok, he said.

“But if you don’t do the research, you’ll never know,” added Lynch, a geneticist and evolutionary biologist at the University of Chicago, United States.

So his team went looking for LIF (short for Leukaemia Inhibiting Factor) genes in 53 mammals, including the African elephant, the bowhead and minke whales, bats and naked mole rats.

In most species, they found a single active LIF gene. But in the modern African elephant – as well as in the manatee and the rock hyrax, both distant cousins of the elephant – they found between seven and 11 additional copies of the LIF gene, called pseudogenes.

In every species but the elephant, these LIF genes and their extra duplicates were inactive: That is, they didn’t turn on or off to produce proteins. If they had been active in the past, their function had been phased out.

In the march of evolution, they had fallen by the wayside and been left for dead, like vast stretches of every species’ genomes.

But in the elephant, Lynch and his colleagues saw that one of the additional copies of the LIF gene was active.

When the researchers induced cell stress – a step that would have led to cancer in most other animals – a widely recognised tumour-suppressor mechanism turned on. That, in turn, activated the LIF6 pseudogene.

Stirred to life, the zombie gene proceeded to carry out its grim programme, entering the internal machinery of damaged cells and ordering them to kill themselves.

In elephant tissue, the damaged cells turned themselves inside-out, and cancer was thwarted before it could gain any momentum.

And when the researchers suppressed the action of the LIF6 “zombie gene”, they found that stressed cells were more likely to form tumours in elephant tissue.

“It’s a fascinating study,” said molecular and cell biologist Vera Gorbunova of the University of Rochester in New York, who has studied the mechanisms by which naked mole rats thwart cancerous cells.

The collective research of Lynch’s group “also raises intriguing questions”, said Gorbunova, who was not involved in the new work.

The group has offered evidence that in their evolution, all complex creatures have made trade-offs, such as taking on genes (including anti-cancer genes) that increase their life span, but reduce their reproductive prowess, or vice versa.

The reanimation of the LIF6 gene may be one way in which elephants have countered what would seem to be a growing threat as they evolved to become bigger, said Lynch.

How? Biological reasoning would suggest that bigger animals would have a greater propensity than very small ones to develop cancer – mainly because they are made up of more cells.

Theoretically, the more cells there are, the higher the odds that one or more will go rogue and seed a tumour.

That is true within species: big dogs (and tall humans) are more likely to develop cancer than smaller members of their species.

But strangely, very large species are not, in general, more likely to develop cancer than are small species – an observation made by epidemiologist Richard Peto that has come to be known as Peto’s Paradox.

In part, “elephants and their extinct relatives (proboscideans) may have resolved Peto’s Paradox” by giving LIF6 new life as a killer of would-be cancer cells, wrote Lynch and his colleagues.

Apparently, not all zombies are to be feared. – Los Angeles Times/Tribune News Service

Is there something fishy going on in fish spas?

Is there something fishy going on in fish spas?

I have recently read a lot of articles about fish pedicures. What are they?

You might have seen a lot of fish pedicure centres in Malaysia. They are not like your regular nail salon pedicure, in which a pedicurist washes and scrapes off the dead skin of your feet and around your nails with instruments.

A fish pedicure is also known as a fish spa. Here, the fish involved are the Middle Eastern and Turkish freshwater fish called Garra rufa. They are also called “doctor fish”. These fish have no teeth.

Since the beginning of this century, the Garra rufa have been used in spa treatments for psoriasis patients. Psoriasis is a disease where the patient has flaky skin.

In this treatment, the patient immerses himself in a bathtub of these fish, and allow the fish to feed on their upper skin layer to help peel it off. The fish spa does not cure psoriasis as there is no cure for it. However, it does alleviate symptoms.

This fish has also been used for patients with eczema. Since then, spas for people without skin problems have latched onto this treatment. But their safety is still being widely debated.

Wait. A fish spa involves the fish actually eating my skin? Isn’t that like what a piranha does?

Not at all. Piranhas are flesh-eating fish that nibble deeper than just the surface of your skin.

The Garra rufa removes dead skin on top of your stratum corneum, or the outer layer of your skin. This is similar to what a traditional pedicurist does – removing dead skin with a foot file or a scrubber. Only, the fish does this in a far more efficient and comprehensive manner.

Traditional pedicurists tend to concentrate more on the area around your nails, and perhaps the calluses on your soles, but tend to neglect other areas. The fish will bite every part of your submerged feet. The word “bite” is very subjective as well, because these fish have no teeth.

A fish spa is not painful either. I, for one, find the sensation very pleasant – once you get over the slight ticklishness of it.

Yes, but are fish spas safe?

That is what the debate is all about now. The US Centre for Disease Control and Prevention (CDC) has published that there have been no illnesses reported from fish spas, but that is back in 2012.

There, however, are many American states, and even Canadian, that ban this sort of spa treatment. Some of reasons for this include:

• The fish pedicure tubs cannot be sufficiently cleaned between customers.

• The fish cannot be “disinfected” or “sanitised’ between customers. Salon owners are likely to use the same fish multiple times with different customers, which increases the risk of spreading infection.

•Garra rufa could pose a threat to native plant and animal life if released into the wild because the fish is not native to the United States.

• The fish must be starved to eat skin, which might be considered animal cruelty.

But please note that even traditional pedicures and manicures have issues about safety sometimes. The pedicurist may use the same instruments between customers and spread infections, especially if blood was involved. The pedicurist may fail to sanitise those instruments. The pedicurist may also damage your skin and nail bed.

Like with any sort of procedure, there is always a risk that you have to take.

Do fish spas spread diseases? What type?

The British Health Protection Agency recently published that fish spa pedicures could spread diseases such as HIV and Hepatitis C, and that patients with a weak immune system, such as those having diabetes or psoriasis, are particularly vulnerable. They however conceded that the risk is extremely low, but could not be completely excluded.

The reasons for the possible disease spread are exactly what has been warned by the US CDC – the fact that many salons do not change the water between customers because it is not financially viable or easily possible.

So if a customer who has HIV and Hepatitis C (which are blood borne diseases) bleeds into the water, there is a risk for this to be passed – especially if the next user has a cut or open wound for the viruses to seep into.

Note that the same infections can be transmitted if the pedicurist does not sterilise his instruments between one user and another. The Health Protection Agency has recommended that the water be changed between customers.

Dr YLM graduated as a medical doctor, and has been writing for many years on various subjects such as medicine, health, computers and entertainment. For further information, e-mail starhealth@thestar.com.my. The information contained in this column is for general educational purposes only. Neither The Star nor the author gives any warranty on accuracy, completeness, functionality, usefulness or other assurances as to such information. The Star and the author disclaim all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.
Animals that defy the rules of aging — like naked mole rats — could help scientists unravel the secrets to longevity

Animals that defy the rules of aging — like naked mole rats — could help scientists unravel the secrets to longevity

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Neil Bromhall/Shutterstock
  • Some long-living animals seem to defy the rules of aging, so scientists are studying them.
  • Two animals of interest to researchers are the naked mole rat, which lives decades longer than its rodent relatives, and turtles, which can live up to 200 years.
  • Researchers have found noticeable differences in the ways these animals’ metabolisms and mitochondria function.

Being a freak of nature isn’t always a bad thing, especially if you defy the conventions of aging.

Naked mole rats and turtles are outliers when it comes to the rules of nature. The mole rat lives up to 31 years, decades longer than its other rodent relatives. Turtles are one of the longest-living creatures on Earth.

Comparing the biology of these animals to others that age poorly provides valuable insights to scientists about which biological pathways are most important for longevity. That information could ultimately help them find ways to increase human lifespans.

A cornucopia of factors are at play as a younger organism gets older: proteins get damaged, they build up and disrupt cell functions, mutations occur, and once-harmless cells turn into cancer. But the important question when it comes to aging is not how it happens, according to Richard Miller, director of the Glenn Center of Aging Research at the University of Michigan.

“The real question is what has been done across species or within a species to slow it,” Miller told Business Insider.

Long live the naked mole rat

A popular theory in the field of aging is that an organism puts most of its resources – such as nutrients, energy, time and effort – either into maintaining their body or reproducing, but not both. In people, for example, women’s average lifespan decreases if they have children. Scientists believe this happens because human reproduction can cause damage to cells and deplete resources in the body that would otherwise have been used for cellular repair.

But paradoxically, breeding seems to extend the life of the naked mole rat.

Scientists Martin Bens and Alessandro Ori at the The Leibniz Institute on Aging in Germany are working to understand this anomaly.

Each colony of mole rats designates a queen, the same way ants do, and only she breeds and bears young. There is also only one breeding male per colony. But non-breeders can transition to become a breeder, so Bens and Ori studied that transition process.

Their results suggested that the signal pathways involved in mole rats’ transition to breeding are also involved in their aging process.

In males, some of these overlapping pathways are related to their metabolism, the process of converting food to usable units of energy in the body. Scientists found that breeding male mole rats produced greater-than-normal amounts of energy in their testes cells, and lower-than-normal amounts in their skin cells. Diverting energy in this way could play a role in delaying the aging process.

Naked Mole Rats

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Brandon Vick, University of Rochester

Ori and Bens also observed differences in the composition of the mole rats’ mitochondria: the small organelles in cells that power metabolic processes. They observed that the naked mole rats had a reduced mitochondria respiration rate compared to guinea pigs, which meant that the mole rats were making less energy and using less fuel and oxygen.

The researchers also found that all the naked mole rats preferred to use lipids or fats as an energy source, rather than the carbohydrates or sugars that shorter-lived rodents mostly use.

Another factor that allows naked mole rats to live so long is their abnormally low body temperature. Lower basal body temperatures in animals are usually correlated with prolonged healthspan, and naked mole rats are mammals but aren’t warm-blooded, which makes them an anomaly in the rodent family.

Finally, Ori and Bens examined naked mole rats’ livers. Livers generally detoxify the body and eliminate chemicals that can damage cells and accelerate aging. In mole rats, these detox pathways were more active than the same systems in guinea pigs, suggesting that mole rats keep their cells healthy and undamaged from toxins more efficiently. That could also explain why they out-live their rodent cousins.

The tortoise and the human

Tortoises and turtles are masters of aging. Jonathan, a Seychelles giant tortoise, is the oldest known terrestrial animal at 186 years of age, and is going strong.

“There are tortoises until recently that knew Darwin personally,” Kenneth Storey, a professor at Carleton University who studies turtles, told Business Insider.

These ancient beings are the most evolved and complex animal that can survive complete anoxia: a total absence of oxygen. Turtles can go well over a year without oxygen.

By comparison, naked mole rats can survive almost 20 minutes without oxygen, and oxygen-deprived humans only get about two minutes of brain activity and five minutes of heart activity before all systems shut down and organs become irreparably damaged.

To live without oxygen, Storey said, turtles drop their metabolism rate to next to nothing.

“What the turtles do is in a tissue-specific manner, shut down genes and sub-cellular organelles that use energy or that need maintenance,” he said.

A giant green turtle rests on a coral reef in the Celebes Sea, November 7, 2005.

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A giant green turtle rests on a coral reef in the Celebes Sea, November 7, 2005.
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Reuters

Turtles shut their energy production off by changing an enzyme called pyruvate dehydrogenase, which turns off their mitochondria.Starving the mitochondria then forces the turtle’s body to secrete a special protein that protects cells.

In the absence of oxygen, turtles can initiate an organized shutdown of 50,000 processes in their bodies.

“We know what happens to the pathways and we know what happens to the system, but we don’t know what ultimately controls it,” Storey said.

He added that under stressful, low-oxygen conditions, turtles’ bodies do one other thing exceptionally well: “They don’t panic.”

In these circumstances, turtles turn off most of their stress-response proteins so they can focus what little energy they have on reshaping their cells to operate differently in anoxic conditions. Those changes include preventing cells from digesting and turning over proteins, a process called autophagy that can make detritus and cause damage. Limiting the amount of matter created and destroyed in their bodies allows turtles to maintain a pristine internal balance.

By comparison, human cells that are deprived of oxygen turn on stress kinases: signaling proteins that help facilitate communication in the body in order to respond to a challenging situation. Over-activating stress kinases can use up a lot of energy, overload the system, and ultimately trigger cell death.

When juxtaposing humans and turtles, Storey thinks longevity depends on an energy trade-off.

“Think of these lower animals as living longer than us because their pilot light is lower. They’re not 37 degrees [Celsius], they’re not racing around,” he said. “They’re not burning the candle at both ends, they’re barely burning the candle at one end, and during anoxia they stop burning the candle. That’s how they can live so long. It’s a pace argument.”

All about energy

The idea that metabolism is one of the key factors in the aging process has been a cornerstone of many studies on aging. Hypothetically, if you turned down the energy production in your cells, you could live longer and get fewer wrinkles, Storey said. But you would probably not have enough energy to sustain a normal human life.

Humans’ complexities mean we require more energy and a constant supply of oxygen to power our cells. We also need to consume food frequently to fuel our bodily functions.

“What we’ve opted for is a high velocity lifestyle, which ties us in to oxygen all the time,” Storey said.

Rozalyn Anderson, an associate professor at the University of Wisconsin School of Medicine and Public Health, told Business Insider that it’s hard to ignore how big a role metabolism and energy balance play in aging. Anderson studies caloric restriction in monkeys, and said evidence is starting to show that age-related diseases show up with increased prevalence in people who have metabolic issues and obesity.

“I think it’s all about energy: energy use, energy storage, and the type of pathways that are being engaged to derive energy,” Anderson said.

Owning a dog can help your health

Owning a dog can help your health

As most of us know by now, this Chinese New Year marks the beginning of the Year of the Earth Dog in the Chinese zodiac.

In celebration of man’s best friend, we round up how your furry friend could give your health a boost in the coming year.

Reduced risk of allergies

Various studies have now found a link between owning a dog and a lower risk of allergies, especially in children.

Research presented in 2017 at the American College of Allergy, Asthma and Immunology (ACAAI) Annual Scientific Meeting detailed how children of mothers who had been in daily contact with a dog while pregnant had a lower risk of eczema by age two, and that pet dogs could also have a protective effect against asthma symptoms.

Swedish researchers also found, after looking at more than one million Swedish children, that those who grew up with dogs had a 15% lower risk of asthma.

Better sleep

A small American study found that despite a dog’s snoring, sleeping with your pooch could actually help you get a better night’s sleep.

After recruiting 40 adults and their pets for the study, researchers at the Mayo Clinic in the United States found that regardless of the size of the dog, sleeping with a furry friend in the room helped some people sleep better.

However, having a dog on the bed didn’t have the same effect, with the team finding that those who let their canines get too cozy, did it at the expense of a good night’s sleep.

“Most people assume having pets in the bedroom is a disruption.

“We found that many people actually find comfort and a sense of security from sleeping with their pets,” commented the study’s author Dr Lois Krahn.

Improved mental health

After looking at 17 research papers, a British review published just this week found that having a pet could have a positive effect on managing long-term mental health conditions.

Owning a dog, or other animal such as a cat, goldfish or hamster, was found to be beneficial by helping to distract owners from the stress of having a mental health problem and helping to alleviate feelings of loneliness.

Dogs also had the added benefit of helping owners increase their level of physical activity through walking, which in turn can also help improve mental health and encourage social interaction with other dog owners.

Pet dogs have also been found to help support children when they are stressed, while a 2015 American study found that children who have a dog at home also have a lower level of anxiety than those who do not.

More exercise

It can be hard to find the motivation to get moving sometimes, but most dog owners will tell you, you don’t have much choice if your dog is asking for walks.

Many recent studies have also found that those with a dog do indeed get more exercise, with a dog being especially beneficial for helping seniors to get out of the house and get moving.

A British study published in 2017 found that seniors who walk their dogs clock up around 30 minutes more physical activity a day than non-dog owners, even during the colder, wetter months, with an Australian study also finding that dog walkers achieved at least 30 minutes of physical activity on more days per week than non-dog walkers, helping them to meet the 150 minutes of physical activity per week currently recommended for good health. – AFP Relaxnews

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