DiversityNursing Blog

Should animal organs be farmed for human transplants?

Posted by Erica Bettencourt

Wed, Sep 17, 2014 @ 12:59 PM

By David McNamee

pig heart resized 600Recently, Medical News Today reported on a breakthrough in xenotransplantation - the science of transplanting functional organs from one species to another. Scientists from the Cardiothoracic Surgery Research Program of the National Heart, Lung and Blood Institute (NHLBI) demonstrated success in keeping genetically engineered piglet hearts alive in the abdomens of baboons for more than a year.

While that is a sentence that might sound absurd, or even nightmarish to some, xenotransplantation is a credible science involving the work of leading scientists and respected organizations like the NHLBI and the Mayo Clinic, as well as large private pharmaceutical firms such as United Therapeutics and Novartis.

What is more, xenotransplantation is not a new science, with experiments in cross-species blood transfusion dating as far back as the 17th century.

Why transplant the organs of animals into living humans?

The reason why xenotransplantation is a burning issue is very simple: because of a crippling shortage of available organs for patients who require transplants, many people are left to die.

US Government information on transplantation reports that an average of 79 people receive organ transplants every day, but that 18 people die each day because of a shortage of organs.

The number of people requiring an organ donation in the US has witnessed a more than five-fold increase in the past 2 decades - from 23,198 in 1991 to 121,272 in 2013. Over the same period, the number of people willing to donate has only doubled - 6,953 donors in 1991, compared with 14,257 donors in 2013.

Although some researchers are attempting to solve this shortage by developing mechanical components that could assist failing organs, these devices are considered to increase the risk of infection, blood clots and bleeding in the patient.

Stem cell research is also actively pursuing the goal of growing replacement organs, but despite regular news of breakthroughs, the reality of a functional lab-grown human organ fit for transplant is a long way off.

As the NHLBI's Dr. Muhammad M. Mohiuddin, who led the team responsible for the baboon trial, explained:

"Until we learn to grow organs via tissue engineering, which is unlikely in the near future, xenotransplantation seems to be a valid approach to supplement human organ availability. Despite many setbacks over the years, recent genetic and immunologic advancements have helped revitalized progress in the xenotransplantation field.

Xenotransplantation could help to compensate for the shortage of human organs available for transplant."

Xenotransplantation's eccentric history

The earliest known example of using animal body parts to replace diseased or faulty components of human bodies dates back to the 17th century, when Jean Baptiste Denis initiated the clinical practice of animal-to-human blood transfusion.

Perhaps predictably, the results were not successful and xenotransfusion was banned in Denis' native France.

Fast forward to the 19th century and a fairly unusual trend for skin xenotransplantation had emerged. Animals as varied as sheep, rabbits, dogs, cats, rats, chickens and pigeons were called upon to donate their skin, but the grafting process was not for the squeamish.

Medical records show that, in order for the xenosurgeons of the time to be satisfied that the donor skin had vascularized (developed capillaries), the living donor animal would usually have to be strapped to the patient for several days. However, the most popular skin donor - the frog - was typically skinned alive and then immediately grafted onto the patient.

Despite several reputed successes, modern physicians are skeptical that these skin grafts could have been in any way beneficial to the patient.

The first corneal xenotransplantation - where the cornea from a pig was implanted in a human patient - took place as early as 1838. However, scientists would not look seriously again at the potential for xenotransplantation until the 20th century and the first successes in human-to-human organ transplantation.

In 1907, the Nobel prize-winning surgeon Alexis Carrel - whose work on blood vessels made organ transplantation viable for the first time - wrote:

"The ideal method would be to transplant in man organs of animals easy to secure and operate on, such as hogs, for instance. But it would in all probability be necessary to immunize organs of the hog against the human serum. The future of transplantation of organs for therapeutic purposes depends on the feasibility of hetero [xeno] transplantation."

These words have been described as "prophetic" because Carrel is describing the exact line of research adopted by xenotransplantation scientists a century later.

A few years later, another leading scientist, Serge Voronoff, would also predict modern science's interest in using the pancreatic islets of pigs to treat severe type 1 diabetes in human patients. However, other xeno experiments by Voronoff have not endured critical reappraisal quite so well.

Voronoff's main scientific interest was in restoring the "zest for life" of elderly men. His attempt to reverse this element of the aging process was to transplant slices of chimpanzee or baboon testicle into the testicles of his elderly patients.

Incredibly, this surgery proved quite popular, with several hundred operations taking place during the 1920s in both the US and Europe.

By the 1960s, despite limited availability, the transplantation of kidneys from deceased to living humans had been established by French and American surgeons.

Dialysis was not yet in practice and given that, in the absence of an available donor kidney, his renal failure patients were facing certain death, the Louisiana surgeon Keith Reemtsma took the unprecedented step of transplanting animal kidneys. He chose chimpanzees as the donor animals, due to their close evolutionary relationship with humans.

Although 12 of his 13 chimpanzee-to-human transplants resulted in either organ rejection or infectious complications within 2 months, one patient of Reemtsma continued to live and work in good health for 9 months, before dying suddenly from acute electrolyte disturbance. Autopsy showed that the chimpanzee kidneys had not been rejected and were working normally.

Experiments in the xenotransplantation of essential organs continued in living patients until the 1980s - without lasting success. However, the procedures attracted widespread publicity, with some attributing a subsequent rise in organ donation to the failed attempt to transplant a baboon heart into a baby girl in 1983.

Where does research currently stand?

Despite the more obvious similarities between humans and other primates, pigs are now considered to be the most viable donor animal for xenotransplantation.

Despite diverging from humans on the evolutionary scale about 80 million years ago, whole genome sequencing of the pig has shown that humans and pigs share similar DNA, while the pig's organs - in size and function - are anatomically comparable to humans.

However, perhaps the main advantage of the pig as donor is in its availability - potentially providing an "unlimited supply" of donor organs. If transplantation is viable, pig donors would provide an immediate solution for the organ shortage problem.

Xenotransplantation optimists also believe that the process can improve on the existing success rate of transplantation of human organs. By keeping the pigs healthy, regularly monitored for infection, and alive right until the point when the required organs are excised under anesthesia, the adverse effects associated with transplantation from deceased donors - such as non-function of organs or transmission of pathogens - would be much less likely, this group argues.

However, there are still significant scientific barriers to the successful implementation of xenotransplantation.

The company United Therapeutics - who moved into xenotransplantation research after the daughter of CEO Martine Rothblatt was diagnosed with pulmonary hypertension, a condition with a 90% shortage rate of available lung donors - claim to be making progress with eliminating these barriers.

MedIcal News Today spoke to Rothblatt, who once claimed that the company will have successfully transplanted a pig lung into a human patient "before the end of the decade."

"For a first clinical trial, which was my goal, I think we are on track," she told us. "I said our goal by end of decade is to transplant a xeno lung into a patient with end-stage lung disease and bring them safely back to health."

As well as pioneering lung xenotransplants, the company has ambitions of making pig kidneys, livers, hearts and corneas available for human transplant.

"All are years away, but lung may well be most difficult," admits Rothblatt. "We call it the canary in the coal mine."

In order to make pig lungs compatible with humans, Rothblatt has estimated that 12 modifications need to be made to the pig genome that will prevent rejection. She claims United Therapeutics have now succeeded in making six of these genome modifications.

Also, it was United Therapeutics' genetically modified piglets that provided the world record-beating pig hearts for the NHLBI study in baboons.

Opposition to xenotransplantation

However, science is not the only obstacle to xenotransplantation. Despite clearing all steps of the research with ethics committees at every step, Rothblatt - who has a doctorate in medical ethics - admits there will be unforeseeable regulatory dilemmas and ethics conversations before xenotransplantation can be accepted into clinical practice.

In 2004, the UK's Policy Studies Institute conducted the first major survey of public attitudes towards potential solutions for the organ shortage crisis. The public perception of xenotransplantation was shown to be overwhelmingly negative.

Indeed, response to animal-to-human transplantation was so hostile that some respondents demanded that it be removed as an option on the survey. Although many respondents considered xenotransplantation unethical, the major concern was that animal viruses could infect humans and spread into the population.

Following the survey, an intriguing debate over the ethics of xenotransplantation took place in the pages of Philosophy Now. Making the case against xenotransplantation, Laura Purdy - professor emerita of philosophy at Wells College in Aurora, NY - commented that "the xeno debate proceeds as if saving lives is our top moral priority." She argues that, from this perspective, it suggests that the lives lost down the line as a result of perfecting xenotransplantation do not count.

"What about the 11 million babies and children who die every year from diarrhea, malaria, measles, pneumonia, AIDS and malnutrition?" she questioned. "What about the half-million women who die every year during pregnancy and childbirth when simple measures could save most of them?"

We asked Prof. Purdy why the fact that people die from matters unrelated to transplantation issues would morally preclude science from attempting to also solve the issue of organ donor shortages.

"I agree that, other things being equal, saying that people are dying from other causes doesn't show why we should not also tackle this cause," she replied.

"But once one has taken on board the larger risks to society, both from the research as well as the deployment of the technology, as well as the probability that this is merely a bridge technology that, hopefully will be made obsolete by future developments (such as partial or whole artificial hearts) or advances in public health (making headway against diabetes) and the probability that both research and implementation will be very expensive, that seriously erodes the case for proceeding.

Resources for health are far from infinite. There is a great deal that we could be doing now to advance human health that does not have these downsides - why not focus more there?"

Whether public attitudes toward xenotransplantation have mellowed in the decade since the Policy Studies Institute's survey is not currently known.

However, as the technology advances and the likelihood of implementation draws closer, so too must the public conversation over the perceived rights and wrongs of animal organ transplantation advance in order to hold the science accountable.

Do you have a view on this issue? If so, use our comments box to join the debate.

Source: http://www.medicalnewstoday.com

Topics: transplants, studies, science, organs, animal, xenotransplantation, health, healthcare, research, human, medical, experiments

Survey: Almost 1 in 5 nurses leave first job within a year

Posted by Erica Bettencourt

Fri, Sep 12, 2014 @ 12:15 PM

survey resized 600

A study in the current issue of Policy, Politics & Nursing Practice estimates 17.5% of newly licensed RNs leave their first nursing job within the first year and 33.5% leave within two years, according to a news release. The researchers found that turnover for this group is lower at hospitals than at other healthcare settings.

The study, which synthesized existing turnover data and reported turnover data from a nationally representative sample of RNs, was conducted by the RN Work Project, funded by the Robert Wood Johnson Foundation. The RN Work Project is a 10-year study of newly-licensed RNs that began in 2006. The study draws on data from nurses in 34 states, covering 51 metropolitan areas and nine rural areas. The RN Work Project is directed by Christine T. Kovner, PhD, RN, FAAN, professor at the College of Nursing, New York University, and Carol Brewer, PhD, RN, FAAN, professor at the School of Nursing, University at Buffalo. 

“One of the biggest problems we face in trying to assess the impact of nurse turnover on our healthcare system as a whole is that there’s not a single, agreed-upon definition of turnover,” Kovner said. “In order to make comparisons across organizations and geographical areas, researchers, policy makers and others need valid and reliable data based on consistent definitions of turnover. It makes sense to look at RNs across multiple organizations, as we did, rather than in a single organization or type of organization to get an accurate picture of RN turnover.”

According to the release, the research team noted that, in some cases, RN turnover can be helpful — as in the case of functional turnover, when a poorly functioning employee leaves, as opposed to dysfunctional turnover, when well-performing employees leave. The team recommends organizations pay attention to the kind of turnover occurring and point out their data indicate that when most RNs leave their jobs, they go to another healthcare job.

“Developing a standard definition of turnover would go a long way in helping identify the reasons for RN turnover and whether managers should be concerned about their institutions’ turnover rates,” Brewer said in the release. “A high rate of turnover at a hospital, if it’s voluntary, could be problematic, but if it’s involuntary or if nurses are moving within the hospital to another unit or position, that tells a very different story.” 

The RN Work Project’s data include all organizational turnover (voluntary and involuntary), but do not include position turnover if the RN stayed at the same healthcare organization, according to the release.

Source: http://news.nurse.com

Topics: jobs, studies, survey, turnover, nursing, nurses, medical, career

Disabilities in children increase, physical problems decline

Posted by Erica Bettencourt

Mon, Aug 18, 2014 @ 01:12 PM

By Associated Press

640 Autism resized 600

Disabilities among U.S. children have increased slightly, with a bigger rise in mental and developmental problems in those from wealthier families, a 10-year analysis found.

Disadvantaged kids still bear a disproportionate burden.

The increases may partly reflect more awareness and recognition that conditions, including autism, require a specific diagnosis to receive special services, the researchers said.

Meantime, physical disabilities declined, as other studies have suggested.

The study is the first to look broadly at the 10-year trend but the results echo previous studies showing increases in autism, attention problems and other developmental or mental disabilities. It also has long been known that the disadvantaged are more likely to have chronic health problems and lack of access to good health care, which both can contribute to disabilities.

The researchers studied parents' responses about children from birth through age 17 gathered in 2000-2011 government-conducted health surveys. Parents were asked about disabilities from chronic conditions including hearing or vision problems; bone or muscle ailments; and mental, behavioral or developmental problems that limited kids' physical abilities or required them to receive early behavioral intervention or special educational services. Nearly 200,000 children were involved.

Results were published online Monday in Pediatrics.

Overall, disabilities of any kind affected 8 percent children by 2010-2011, compared to close to 7 percent a decade earlier. For children living in poverty, the rate was 10 percent at the end of the period, versus about 6 percent of kids from wealthy families.

The overall trend reflects a 16 percent increase, while disabilities in kids from wealthy families climbed more than 28 percent, the researchers found. The trend was fueled by increases in attention problems, speech problems and other mental or developmental disorders that likely include autism although that condition isn't identified in the analyzed data.

Declines in asthma-related problems and kids' injuries accounted for much of the overall 12 percent drop in physical disabilities. Better asthma control and treatment and more use of bike helmets, car seats and seat-belts may have contributed to that trend, said lead author Dr. Amy Houtrow, a pediatric rehabilitation specialist at the University of Pittsburgh.

The developmental disability increases echo what Dr. Kenneth Norwood, a developmental pediatrician in Charlottesville, Virginia sees in his medical practice.

"I'm routinely backed up six months for new patients," said Norwood, chairman of the American Academy of Pediatrics' Council on Children with Disabilities.

Norwood thinks there is more awareness of these conditions and that some, including autism, are truly rising in prevalence. Autism is thought to result from genetic flaws interacting with many other factors. Some studies have suggested these may include parents' age and prenatal infections.

Source: www.foxnews.com

Topics: US, studies, healthcare, children, disabilities, physical

Many Kids Don't Have A Realistic Take On Their Weight

Posted by Erica Bettencourt

Mon, Jul 28, 2014 @ 01:05 PM

By Michelle Healy

1396890632000 XXX XXX 107069231 resized 600

Nearly one-third of U.S. children and adolescents are obese or overweight, but many don't realize that they fall into that category.

According to new government statistics, approximately 30% of children and adolescents ages 8-15 years (32% of boys and 28% of girls) — an estimated 9.1 million young people — don't have an accurate read on their own weight.

About 33% of kids (ages 8–11) and 27% of teens (ages 12–15) misperceive their weight status, says the report from the National Center for Health Statistics.

Based on data collected between 2005 and 2012 from more than 6,100 kids and teens for the National Health and Nutrition Examination Survey (NHANES), the report also finds:

• 42% of those classified as obese (48% of boys; 36% of girls) considered themselves to be about the right weight.

• 76% of those classified as overweight (81% of boys; 71% of girls) believed they were about the right weight.

• 13% of those classified as being at a healthy weight considered themselves too thin (9%) or too fat (4%).

Studies have shown that recognizing obesity can be an important step in reversing what is a major health problem for U.S. children and adolescents, and it can be an important predictor of later weight-control behaviors, says Neda Sarafrazi, a nutritional epidemiologist at NCHS and lead author of the report.

"When overweight kids underestimate their weight, they are less likely to take steps to reduce their weight or do additional things to control their weight, like adopt healthier eating habits or exercise regularly," Sarafrazi says.

"On the other hand, when normal weight or underweight kids overestimate their weight, they might have unhealthy weight-control behaviors," she says.

Weight misperception varied by race and Hispanic origin, according to the report. Black and Mexican-American youths were more likely to misperceive their weight than white children. It also varied by income level and was significantly less common among higher-income families compared with lower-income families.

The report's findings are not a surprise, says Timothy Nelson, an assistant professor of psychology at the University of Nebraska-Lincoln. He was not involved in the study.

"In general, children and adolescents have a tendency to underestimate their health risks, and this certainly appears to be the case with obesity," says Nelson, who studies pediatric health behaviors. "We see a similar pattern of misperception when parents are asked about their children's weight. Parents are often unaware of the problem."

With obesity so prevalent today, it's understandable that many kids might have a skewed take on their weight, he says. "If they are surrounded by people who are overweight, they may be less likely to label their own weight as a problem."

The findings highlight the need for health professionals "to communicate with families about the child's weight," Nelson says. "This can be a tough conversation when the child is overweight, but it is critical that pediatricians help parents understand where their child stands and what steps need to be taken to get the child on a healthier track."

Source: http://www.usatoday.com

Topics: studies, kids, weight, overweight, pediatricians, obesity, health

Study: Fist Bumps Are Less Germy Than Handshakes

Posted by Erica Bettencourt

Mon, Jul 28, 2014 @ 12:45 PM

By Kim Painter

1406316038000 AP OBAMA 65540516 resized 600

A nice firm handshake has long been a mark of good manners and elevated social skills.

It is also a very germy way to greet your fellow humans, much worse than a couple of more casual alternatives, a new study shows.

"A short, sweet fist bump will transmit the least bacteria," and even a high-five is better than a traditional shake, says David Whitworth, a senior lecturer in biochemistry at Aberystwyth University-Ceredigion in the United Kingdom.

Whitworth and a colleague systematically tested the three greetings for a study published Monday in the American Journal of Infection Control.

For the experiment, one of them repeatedly dipped a gloved hand into a container loaded with a not-too-dangerous strain of E. coli bacteria. The dirty-gloved scientist let the film dry, then shook, fist-bumped or high-fived the other person's clean, gloved hand. Finally, the receiving gloves were tested for bacteria.

Result: The shakes transmitted about 10 times more bacteria than the fist bumps and about two times more than the high fives. The longest, firmest shakes transmitted the most.

In a separate round in which the gloves were dipped in paint rather than bacteria, the researchers found one rather obvious explanation: Bigger areas of the hands touched during the shakes. Handshakes also tended to last longer, but the researchers found more clinging germs even when they compared shakes to fist bumps and high-fives of the same duration.

Since we don't go around dipping our hands in vats of bacteria, the experiment does not perfectly mimic real life – in which different areas of the hand carry different amounts of bacteria, for one thing. It does provide some new ammunition for those who would like to ban handshaking in hospitals and other places where germs are a particular concern.

Whitworth says it also provides an especially good alternative, the fist bump. "You can't really imagine a world where people don't greet each other physically," he says. "It seems to be a basic human need."

Whitworth's findings "are not surprising," says Mary Lou Manning, an associate professor in the school of nursing at Thomas Jefferson University in Philadelphia and president-elect of the Association for Professionals in Infection Control and Epidemiology.

She is not enthusiastic about replacing handshakes with fist bumps in hospitals. The better, more hygienic idea, she says, is to promote rigorous hand-washing and ban hand-to-hand greetings altogether. "That's already starting to happen" in a lot of places, she says.

She says she "can't even imagine" health workers and patients greeting one another with a casual fist bump. A nod or slight bow might be nicer, she says.

Whitworth concedes that the perceived informality of fist bumps and high fives might be a problem. Figures as august as President Obama and the Dalai Lama have used them, he notes – "but I couldn't imagine the British prime minister doing that."

Source: www.usatoday.com

Topics: studies, germs, handshakes, fist bump, bacteria, social skills

Recent Jobs

Article or Blog Submissions

If you are interested in submitting content for our Blog, please ensure it fits the criteria below:
  • Relevant information for Nurses
  • Does NOT promote a product
  • Informative about Diversity, Inclusion & Cultural Competence

Agreement to publish on our DiversityNursing.com Blog is at our sole discretion.

Thank you

Subscribe to Email our eNewsletter

Recent Posts

Posts by Topic

see all