A radical procedure that involves replacing a patient’s blood with cold salt water could retrieve people from the brink of death, says David Robson.
Rhee isn’t exaggerating. With Samuel Tisherman, at the University of Maryland, College Park, he has shown that it’s possible to keep bodies in ‘suspended animation’ for hours at a time. The procedure, so far tested on animals, is about as radical as any medical procedure comes: it involves draining the body of its blood and cooling it more than 20C below normal body temperature.
Once the injury is fixed, blood is pumped once again through the veins, and the body is slowly warmed back up. “As the blood is pumped in, the body turns pink right away,” says Rhee. At a certain temperature, the heart flickers into life of its own accord. “It’s quite curious, at 30C the heart will beat once, as if out of nowhere, then again – then as it gets even warmer it picks up all by itself.” Astonishingly, the animals in their experiments show very few ill-effects once they’ve woken up. “They’d be groggy for a little bit but back to normal the day after,” says Tisherman.
Tisherman created headlines around the world earlier this year, when he announced that they were ready to begin human trials of the technique on gunshot victims in Pittsburgh, Pennsylvania. The first patients will have been so badly wounded that their hearts have stopped beating, meaning that this is their last hope. “Cheating death with ‘suspended animation’” is how CNN put it; “Killing a patient to save his life” was the New York Times’ take.
The news coverage has sometimes offended Tisherman’s cautious sensibility. During our conversation, he comes across as a thoughtful, measured man, who is careful not to oversell his research. He is particularly wary of using the term ‘suspended animation’. “My concern isn’t that it’s inaccurate – it’s that when people think of the term, they think about space travellers being frozen and woken up on Jupiter, or Han Solo in Star Wars,” he says. “That doesn’t help, because it’s important for the public to know it’s not science fiction – it’s based on experimental work and is being studied in a disciplined manner, before we use it to stop people dying.” Rhee, who came to global attention after treating congresswoman Gabrielle Giffords after a shooting in 2011, tends to be bolder: he says he wouldn’t rule out longer-term suspended animation, in the distant future. “What we’re doing is beginning part of that experiment.”
Tisherman’s quest to bring people back from the brink of death began at medical school, where he studied under Peter Safar. It is an inspiring dynasty: in the 1960s Safar had pioneered cardiopulmonary resuscitation (CPR), the now familiar procedure of applying pressure to the chest cavity to try to massage the heart back to life.
Safar’s work began to change our perceptions of death – blurring the point that is meant to mark the end of our lives. “We’ve all been brought up to think death is an absolute moment – when you die you can’t come back,” says Sam Parnia, at the State University of New York in Stony Brook. “It used to be correct, but now with the basic discovery of CPR we’ve come to understand that the cells inside your body don’t become irreversibly ‘dead’ for hours after you’ve ‘died’… Even after you’ve become a cadaver, you’re still retrievable.”
Tisherman now thinks of death as the (admittedly subjective) point at which doctors give up resuscitation as a lost cause – but even then, some people can still make a remarkable comeback. Last December, a paper in the journal Resuscitation caused a stir by suggesting that 50% of surveyed emergency doctors have witnessed ‘Lazarus phenomena’, in which a patient’s heart has begun beating again by itself, after doctors had given up hope.
Kick-starting the heart is only one half of the doctor’s battle, however; the lack of oxygen after a cardiac arrest can cause serious damage to the body’s vital organs, particularly the brain. “Every minute that there’s no oxygen to those organs, they start dying,” says Tisherman. His former mentor, Safar, came up with a solution to this problem too, with ‘therapeutic hypothermia’, a procedure that involves cooling the body, typically to around 33C by placing ice packs around the body, for instance. At lower temperatures, cells begin to work in slow motion, reducing their metabolism and the damage that could be caused by oxygen starvation.
Combined with machines that can take over circulation and pump oxygen into the blood stream while the heart is being revived, this has helped open the window between cardiac arrest and brain death. One hospital in Texas recently reported that an 40-year-old man had survived, with his mind intact, after three-and-a-half hours of CPR. His treatment involved a constant rotation of medical students, nurses and doctors taking it in turns to perform the chest compressions. “Anybody in the room who had two arms was asked to jump in,” says one of the attending doctors, Scott Taylor Bassett. Such cases are rare, however: Bassett, points out that they were only motivated to continue because the patient regained consciousness during the CPR, despite the fact that his heart was still not functioning. “During the chest compressions he would speak to us, showing he was neurologically intact,” says Bassett. “I’ve never seen it before or since – it was the defining moment of the entire decision making.”
Such long-term resuscitation is currently impossible for people whose cardiac arrest is accompanied by injury from trauma – such as gunshot wounds or automobile accidents. At the moment, the surgeon’s best option is to clamp the arteries leading to the lower body, before opening the chest and massaging the heart, which pushes a little blood flow to the brain while surgeons try to stitch up the wounds. Unfortunately, the survival rate is less than one in 10.
It is for this reason that Tisherman wants to plunge the body to around 10-15C, potentially giving the doctors a window of two or more hours to operate. Although this level of deep hypothermia is sometimes applied during heart surgery, Tisherman’s project is the first time that it will have been be used to revive someone who had already ‘died’ before entering the hospital. Perhaps most astonishing of all, the team drain the blood from the body and replace it with chilled saline solution. Because the body’s metabolism has stopped, the blood is not required to keep cells alive, and saline solution is the quickest way to cool the patient, explains Tisherman.
With Rhee and others, Tisherman has spent two decades building a substantial portfolio of evidence to prove that the procedure is safe, and effective. Many of the experiments involved pigs inflicted with near-fatal injuries. Mid-operation, there was no doubt that animals were about as far beyond the realms of the living as it is possible to go and then return. “The pig is as white as you can get,” says Rhee. “It’s just pale, refrigerator meat.” If the animals had been cooled quickly enough, however – at around 2C a minute – nearly 90% recovered when their blood was returned to their bodies, after having lain in limbo for more than an hour. “It’s the most amazing thing to witness – when the heartbeat comes back,” says Rhee.
Once the animals had returned back to more regular activity, the team then performed several tests to check that their brains hadn’t been damaged. For instance, before the procedure, the researchers trained some of the pigs to open a container of a certain colour, where an apple was hidden inside. After they had been revived, most of the animals remembered where to fetch their treat. Other pigs that hadn’t been trained before the operation, were instead taught the procedure soon after their recovery. They managed to learn just as quickly as the others – again suggesting that there had been no effect on their memories.
Needless to say, gaining approval for human trials has been a struggle. Earlier this year, Tisherman was finally allowed to set up a pilot trial in Pittsburgh to treat patients suffering from gunshot wounds. The hospital sees about one or two such patients a month, meaning that some have already been treated with the technique since the trial began – although it is too early for Tisherman to speak about the results yet. He is also setting up a trial in Baltimore, Maryland, and all being well, Rhee will later be able to begin work at Tuscon’s trauma centre.
As with any medical research, there will be some challenges in the transition from the animal experiments to the human trials. The animals received their own blood at the end of the operation, for instance – whereas the patients in this trial will need transfusions that have been sitting in blood banks for weeks. And while the animals were under anaesthesia at the time of injury, the patients won’t have been, which could change the way their body reacts to the injury. Tisherman remains optimistic, however. “We generally think that dogs and pigs respond to bleeding in a similar way to humans.”
Other doctors are watching with interest. “It’s very brave,” says Parnia. “Many of us feel that in order to preserve the brain, we have to cool the body a lot more than we’ve done traditionally. But people have been afraid.”
If the trials go according to plan, Tisherman would like to extend the approach to other kinds of trauma. Gunshot victims were chosen for the initial trial because it is easier to localise the source of blood loss, but he hopes eventually to treat internal bleeding from an automobile accident, for instance. It may even, one day, be used to treat people suffering from heart attacks and other kinds of illness.
Success could also pave the way for investigations into other forms of suspended animation. Some scientists are looking into whether a cocktail of drugs added to the saline solution pumped into body could further reduce the body’s metabolism and prevent injury. One promising candidate was hydrogen sulphide – the chemical that gives rotten eggs their smell – but although it has been found to reduce the metabolism of some animals, there is little evidence that it improves their chances of survival after a cardiac arrest. Tisherman instead thinks it will be better to find some potent anti-oxidants that can mop up the harmful chemicals that cause injury.
For Rhee, the need for better treatment is all too urgent. He points out the fate of a patient he saw at the hospital only the day before we spoke. “He was shot in the epigastrium, right under the chest in the middle of the belly,” he says. The hospital staff tried everything they could, but he still died. “It’s exactly the kind of patient we hope we could repair if we’d been able to work in a less rushed fashion.”
It has long been known that happiness depends on many different life circumstances.
Now scientists have developed a mathematical equation that can predict momentary delight.
They found that participants were happiest when they performed better than expected during a risk-reward task.
Brain scans also revealed that happiness scores correlated with areas known to be important for well-being.
Scientists said Sunday they may have unravelled how chronic stress leads to heart attack and stroke: triggering overproduction of disease-fighting white blood cells which can be harmful in excess.
Surplus cells clump together on the inner walls of arteries, restricting blood flow and encouraging the formation of clots that block circulation or break off and travel to another part of the body.
White blood cells “are important to fight infection and healing, but if you have too many of them, or they are in the wrong place, they can be harmful,” said study co-author Matthias Nahrendorf of the Harvard Medical School in Boston.
Doctors have long known that chronic stress leads to cardiovascular disease, but have not understood the mechanism.
To find the link, Nahrendorf and a team studied 29 medical residents working in an intensive care unit.
Their work environment is considered a model for chronic stress exposure given the fast pace and heavy responsibility they carry for life-and-death decisions.
Comparing blood samples taken during work hours and off duty, as well as the results of stress perception questionnaires, the researchers found a link between stress and the immune system.
Particularly, they noticed stress activate bone marrow stem cells, which in turn triggered overproduction of white blood cells, also called leukocytes.
White blood cells, crucial in wound healing and fighting off infection, can turn against their host, with devastating consequences for people with diseases like atherosclerosis — a thickening of artery walls caused by a plaque buildup.
The study then moved on to mice, which were exposed to the rodent equivalent of stress through techniques like crowding and cage tilting.
The team chose atherosclerosis-prone mice.
They found that excess white blood cells produced as a result of stress accumulated on the inside of arteries and boosted plaque growth.
“Here, they (the cells) release enzymes that soften the connective tissue and lead to disruption of the plaque,” said Nahrendorf.
“This is the typical cause of myocardial infarction (heart attack) and stroke.”
He added leukocytes were only a part of the picture — factors like high cholesterol and blood pressure, smoking and genetic traits also contribute to heart attack and stroke risk.
“Stress might push these over the brink,” the researcher told AFP. – AFP Relaxnews
The hormone known for creating soothing sensations during pleasant social and physical interactions might one day be used to maintain and repair aging muscles, according to a study conducted at the University of California at Berkeley.
Researchers say oxytocin, which is released during breastfeeding, sex, and even a warm hug, could become a viable treatment for age-related muscle wasting or sarcopenia.
Associated with social and romantic attachements, oxytocin increases libido and is thought to create social, familial and romantic bonds.
“This is the hormone that makes your heart melt when you see kittens, puppies and human babies,” said principal investigator Irina Conboy, associate professor of bioengineering and a member of the Berkeley Stem Cell Center and of the California Institute for Quantitative Biosciences (QB3). “There is an ongoing joke among my research team that we’re all happy, friendly and trusting because oxytocin permeates the lab.”
In the study, which was published in the journal Nature Communications, researchers observed oxytocin levels in mice and found them to decline with age.
Older mice were observed to have fewer oxytocin receptors in muscle stem cells.
Upon being injected with the hormone, the injured muscles of the older mice began to repair themselves after just nine days.
“The action of oxytocin was fast,” said Christian Elabd, a senior scientist in Conboy’s lab and study co-author. “The repair of muscle in the old mice was at about 80 percent of what we saw in the young mice.”
Of notable interest is that young mice that received oxytocin injections did not undergo muscular change, according to senior scientist and lead study co-author Wendy Cousin.
“This is good because it demonstrates that extra oxytocin boosts aged tissue stem cells without making muscle stem cells divide uncontrollably,” Cousin added.
Cousin envisions that oxytocin — already the key ingredient in the drug Picotin, administered to induce labor — will overtake traditional hormone replacement therapy as the go-to anti-aging treatment for women and men. Hormone replacement therapy is associated with numerous health risks and has proven ineffective in muscle regeneration.
An article by Tara Parker-Pope
From tribesmen to billionaire philanthropists, the social value of generosity is already well known. But new research suggests it also matters much more intimately than we imagined, even down to our most personal relationships.
Researchers from the University of Virginia’s National Marriage Project recently studied the role of generosity in the marriages of 2,870 men and women. Generosity was defined as “the virtue of giving good things to one’s spouse freely and abundantly” — like simply making them coffee in the morning — and researchers quizzed men and women on how often they behaved generously toward their partners. How often did they express affection? How willing were they to forgive?
The responses went right to the core of their unions. Men and women with the highest scores on the generosity scale were far more likely to report that they were “very happy” in their marriages. The benefits of generosity were particularly pronounced among couples with children. Among the parents who posted above-average scores for marital generosity, about 50 percent reported being “very happy” together. Among those with lower generosity scores, only about 14 percent claimed to be “very happy,” according to the latest “State of Our Unions” report from the National Marriage Project.
While sexual intimacy, commitment and communication are important, the focus on generosity adds a new dimension to our understanding of marital success. Though this conclusion may seem fairly self-evident, it’s not always easy to be generous to a romantic partner. The noted marriage researcher John Gottman has found that successful couples say or do at least five positive things for each negative interaction with their partner — not an easy feat.
“In marriage we are expected to do our fair share when it comes to housework, child care and being faithful, but generosity is going above and beyond the ordinary expectations with small acts of service and making an extra effort to be affectionate,” explains the University of Virginia’s W. Bradford Wilcox, who led the research. “Living that spirit of generosity in a marriage does foster a virtuous cycle that leads to both spouses on average being happier in the marriage.”
Social scientists are now wondering if this virtuous cycle extends to children too. In a study of 3-year-old twins, Israeli researchers have identified a genetic predisposition toward generosity that may be further influenced by a parent’s behavior. Preliminary findings suggest that children with more-engaged parents are more likely to be generous toward others, which may bode well for their future relationships — and their parents’ too.
“We see meaningful differences in parents’ behaviors,” said Ariel Knafo, the principal investigator and a psychologist at Hebrew University in Jerusalem. “In the long run we’d like to be able to see whether it’s children’s generosity that also makes parents more kind or the other way around. Probably it’s both.”
Eating more whole fresh fruit, especially blueberries, grapes, apples and pears, is linked to a lower risk of Type 2 diabetes, but drinking more fruit juice has the opposite effect, says a study.
British, US and Singaporean researchers pored over data from three big health investigations that took place in the United States, spanning a quarter of a century in all.
More than 187,000 nurses and other professional caregivers were enrolled.
Their health was monitored over the following years, and they regularly answered questionnaires on their eating habits, weight, smoking, physical activity and other pointers to lifestyle.
Around 6.5 percent of the volunteers developed diabetes during the studies.
People who ate at least two servings each week of certain whole fruits, especially blueberries, grapes and apples, reduced their risk of Type 2 diabetes by as much as 23 percent compared to those who ate less than one serving per month.
“Our findings provide novel evidence suggesting certain fruits may be especially beneficial for lower diabetes risk,” said Qi Sun, an assistant professor of nutrition at the Harvard School of Public Health.
On the other hand, those who consumed one or more servings of fruit juice each day saw their risk of the disease increase by as much as 21 percent.
Swapping three servings of juice per week for whole fruits resulted in a seven-percent reduction in risk, although there was no such difference with strawberries and cantaloupe melon.
The paper, published on Friday by the British Medical Journal (BMJ), says further work is needed to explore this “significant” difference.
It speculates that, even if the nutritional values of whole fruit and fruit juice are similar, the difference lies with the fact that one food is a semi-solid and the other a liquid.
“Fluids pass through the stomach to the intestine more rapidly than solids even if nutritional content is similar,” says the paper.
“For example, fruit juices lead to more rapid and larger changes in serum [blood] levels of glucose and insulin than whole fruits.”
The study also points to evidence that some kinds of fruit have a beneficial effect for health.
Berries and grapes, for instance, have compounds called anthocyanins which have been found to lower the risk of heart attacks.
But, say the authors, how or even whether this also applies to diabetes risks is for now unclear.
The investigation looked at data from the Nurses’ Health Study, which ran from 1984-2008; the Nurses’ Health Study II (1991-2009); and the Health Professionals Follow-Up Study (1986-2008).
Ten kinds of fruit were used in the questionnaire: grapes or raisins; peach, plums or apricots; prunes; bananas; cantaloupe melon; apples or pears; oranges; grapefruit; strawberries; and blueberries.
The fruit juices identified in the questionnaire were apple, orange, grapefruit and “other.” – AFP/Relaxnews, September 2, 2013.
A NEW study finds that eating a weekly portion of salmon or other fatty fish, such as trout or mackerel, could reduce your risk of developing rheumatoid arthritis by more than half.
In a study published Monday in the Annals of Rheumatic Diseases, the Karolinska Institute in Stockholm found that the omega-3 fatty acids in fish can cut the risk of chronic inflammatory disease by 52 percent.
Prior research from 2009 suggests that consuming fish oils could help reduce inflammation that leads to a variety of diseases, including rheumatoid arthritis. In this study, researchers highlighted the benefit to long-chain omega-3 polyunsaturated fatty acid (Pufa) content in fish.
If you prefer lean fish, such as cod or canned tuna, the same benefit could be found in eating four servings a week, the researchers found. Long-term, weekly consumption of any type of fish was associated with a 29 percent lower risk of the disease.
However you’ll need to sustain a regular diet of fish for at least 10 years to enjoy the health prevention against the condition, they added.
To reach their findings, head researcher Alicja Wolk and her team analyzed the diets of 32,232 Swedish born between 1914 and 1948. Subjects completed questionnaires about their food intake and lifestyle in 1987 and 1997. Women who consumed at least 0.21g of omega-3 Pufas daily had the 52 percent reduced risk, the study found. – AFP Relaxnews
A team of researchers said Wednesday that it had produced embryonic stem cells — a possible source of disease-fighting spare parts — from a cloned human embryo.
Scientists at the Oregon Health and Science University accomplished in humans what has been done over the past 15 years in sheep, mice, cattle and several other species. The achievement is likely to, at least temporarily, reawaken worries about “reproductive cloning” — the production of one-parent duplicate humans.
But few experts think that production of stem cells through cloning is likely to be medically useful soon, or possibly ever.
“An outstanding issue of whether it would work in humans has been resolved,” said Rudolf Jaenisch, a biologist at MIT’s Whitehead Institute in Cambridge, Mass., who added that he thinks the feat “has no clinical relevance.”
“I think part of the significance is technical and part of the significance is historical,” said John Gearhart, head of the Institute for Regenerative Medicine at the University of Pennsylvania. “Many labs attempted it, and no one had ever been able to achieve it.”
A far less controversial way to get stem cells is now available. It involves reprogramming mature cells (often ones taken from the skin) so that they return to what amounts to a second childhood from which they can grow into a new and different adulthood. Learning how to make and manipulate those “induced pluripotent stem” (IPS) cells is one of biology’s hottest fields.
Stem cells have the capability of maturing into different types of tissue depending on how they are stimulated. Embryonic stem cells (ESCs), plucked from a microscopic embryo, have the greatest potential. With the right molecular nudges, they could theoretically be used to grow new kidneys, lungs and hearts for use by people whose own organs have worn out.
Some experts think that “regenerative medicine” will eventually become an approach to healing that is as important as surgery or pharmacology.
The Oregon researchers, led by Shoukhrat Mitalipov, produced embryonic stem cells through “somatic cell nuclear transfer,” the technique used in 1996 to make Dolly the sheep the first cloned mammal.
The nucleus of a mature cell is transplanted into a human oocyte (egg) whose own nucleus has been removed. After the right stimulation, this new hybrid cell starts to divide and develop just as a sperm-fertilized egg would. When it is at the “blastocyst” stage — about 100 cells — its core contains a small number of embryonic stem cells capable of becoming any type of cell possessed by the human body.
But getting the doctored egg to grow even that far is extremely difficult. For some species, hundreds of eggs must be subjected to nuclear transfer before any produce viable embryonic stem cells. The failure of human oocytes to produce them had led some scientists to speculate that the technique simply might not work in people for some reason.
Mitalipov and several members of his team work at the Oregon National Primate Research Center and had refined their techniques using rhesus monkeys. They used nuclei from the skin cells of newborns or, in some cases, fetuses. Their stimulants included a pulse of electricity at the time of nuclear transfer and the addition of caffeine to the fluid cells lived in.
The tweaks and improvements apparently made all the difference. In one experiment, eight oocytes harvested from one woman produced five blastocysts and four embryonic stem cell lines — a success rate virtually unseen in other animals. The researchers subsequently proved cells were “pluripotent” by coaxing them to become, among other things, beating heart muscle cells.
The experiments were reported in a paper published online in the journal Cell.
“Where the kudos come is in being able to over time enhance and improve the technology developed in other species to make this amenable to the human oocyte,” Gearhart said.
The blastocysts could be implanted in a woman’s uterus. It might develop into a fetus. Most cloned animals, however, turn out to have major health problems and shortened lives.
“We just need to make sure it’s clear to the public that no one in their right mind would want to do that. There is no intent to do reproductive cloning. None at all,” Gearhart said.
Are these embryonic stem cells more versatile than IPS cells made by reprogramming skin cells?
“That’s of interest,” Jaenisch said. But whatever the answer, “the consequence would be to make the IPS cells better.” Given the difficulty of obtaining human oocytes, and the controversial nature of the research, embryonic stem cells aren’t likely to ever be the preferred tool of regenerative medicine, he said.
Source: Washington Post
A chemical found in red meat helps explain why eating too much steak, mince and bacon is bad for the heart, say US scientists.
A study in the journal Nature Medicine showed that carnitine in red meat was broken down by bacteria in the gut.
This kicked off a chain of events that resulted in higher levels of cholesterol and an increased risk of heart disease.
Dieticians warned there may be a risk to people taking carnitine supplements.
There has been a wealth of studies suggesting that regularly eating red meat may be damaging to health.
In the UK, the government recommends eating no more than 70g of red or processed meat a day – the equivalent of two slices of bacon.
Saturated fat and the way processed meat is preserved are thought to contribute to heart problems. However, this was not thought to be the whole story.
“The cholesterol and saturated fat content of lean red meat is not that high, there’s something else contributing to increases in cardiovascular risk,” lead researcher Dr Stanley Hazen told the BBC.
Experiments on mice and people showed that bacteria in the gut could eat carnitine.
Carnitine was broken down into a gas, which was converted in the liver to a chemical called TMAO.
In the study, TMAO was strongly linked with the build-up of fatty deposits in blood vessels, which can lead to heart disease and death.
Dr Hazen, from the Cleveland Clinic, said TMAO was often ignored: “It may be a waste product but it is significantly influencing cholesterol metabolism and the net effect leads to an accumulation of cholesterol.
“The findings support the idea that less red meat is better.
“I used to have red meat five days out of seven, now I have cut it way back to less than once every two weeks or so.”
He said the findings raised the idea of using a probiotic yogurt to change the balance of bacteria in the gut.
Reducing the number of bacteria that feed on carnitine would in theory reduce the health risks of red meat.
Vegetarians naturally have fewer bacteria which are able to break down carnitine than meat-eaters.