The kiss may have evolved for reasons that are far more practical – and less alluring – than prevously thought.British scientists believe it developed to spread germs.
They say that the uniquely human habit allows a bug that is dangerous in pregnancy to be passed from man to woman to give her time to build up immunity.
Cytomegalovirus, which lurks in saliva, normally causes no problems. But it can be extremely dangerous if caught while pregnant and can kill unborn babies or cause birth defects. These can include problems ranging from deafness to cerebral palsy.
Writing in the journal Medical Hypotheses, researcher Dr Colin Hendrie from the University of Leeds said: “Female inoculation with a specific male’s cytomegalovirus is most efficiently achieved through mouth-to-mouth contact and saliva exchange, particularly where the flow of saliva is from the male to the typically shorter female.”
Kissing the same person for about six months provides optimum protection, he added. As the relationships progresses and the kisses become more passionate, her immunity builds up.
That anti-wrinkle cream may look tempting — but scientists say there’s more to ageing than creased skin and greying hair. These are just the telltale signs of age. What gets eroded inside the body is the real problem.
If some scientists have their way, it won’t be a problem for long. They are trying to battle an ageing heart, hip and knees that give in to the wear and tear of passing years and blood veins that cannot keep up with the demands of round-the-clock blood circulation, leading to dead cells.
John Fisher, a professor of mechanical engineering at the University of Leeds, the UK, is determined to look into these problems and find solutions so that people can lead an active life beyond the age of 50. While people are living longer than ever before, the effort is to help them discard the baggage of old age.
The West is facing a crisis — of an increasing older population. There are nearly 35 pensioners for every 100 workers in European countries. The pensioners are expected to surge to 75 for every 100 workers by 2050. According to a recent study in Lancet, half the babies now born in wealthy nations are expected to live to the age of 100 years, further aggravating the problem.
The Institute of Medical and Biological Engineering (iMBE), which Fisher heads at the university, will spend £50 million (Rs 375 crore) over the next year to tackle 10 challenges that will allow people “50 active years after 50”.
The project, launched in partnership with academic institutions and private industry from a number of countries, intends to develop long-lasting, better performing biomedical implants and regeneration techniques.
On the list are regenerated heart valves, vein-repair patches, new ligaments and cartilage, spare skin and replacement joints that can be bought off the shelf.
While medical advances, a better diet and changes in our lifestyle mean we are living longer, our bones, joints and cardiovascular systems continue to degenerate as we age, says Fisher.
Current technologies are good, but they are not adequate to last 50 years. For instance, the best of artificial hip joints can’t last more than 15-20 years at a stretch, “particularly if you want to cycle, play tennis, or ski,” says Fisher. “There is a crying need to improve the quality and durability of prostheses available for use currently,” adds Sanjeev Jain, a consulting orthopaedic surgeon and joint replacement expert at the Dr L.H. Hiranandani Hospital in Mumbai.
A typical replacement hip joint has a metal head in a polyethylene cup, which wears out over time. Because of its limited lifespan, many patients are advised to wait for as long as possible, often in considerable discomfort, before having an artificial hip put in place.
There is another design which is used in younger patients. Since a relatively younger person who needs a hip replacement may take 100 million steps for the rest of his or her lifetime, the artificial hip joint has to last longer. The replacement hips now available for younger patients are either made of metal or ceramics. Both are more durable than polyethylene, giving the joint a longer lifespan and reducing the need for a further surgery.
A few years ago, the Leeds university team further modified the design to create a better model. Both ceramics and metal are used in the new hip joint. The bearing includes a new type of ceramic ball, which fits inside a metal cup. The combination has led to a 10-fold reduction in metal wear than in the metal joint. The joints, in clinical trials for the last five years, were found to be 10 times more durable than the other designs. Over 10,000 people are living with these new-generation hip replacements.
Similarly, as we get older, soft tissues begin to wear out — affecting organs such as the heart. A person with damaged tissues can go for an artificial implant, a chemically treated animal tissue or use a human donor tissue. An artificial implant or animal tissue will not lead to new tissues. The human donor tissue contains foreign cells which may eventually lead to the decay of the tissue.
On the other hand, the iMBE scientists have already developed a novel technique for re-creating human tissues. Developed and patented in 2001, it employs a unique method of stripping cells from human and animal tissues to leave a “scaffold” into which the patient’s own cells can be introduced.
“We have already used this to make a range of soft tissues,” says Eileen Ingham, professor of medical immunology at Leeds. These include heart valves, membranes that can be used for surgical and vascular repair, ligaments, cartilage found in knee joints and tissues such as skin and bladder, she says.
Take the heart valve. There are, as of now, three options available to patients who require a heart valve replacement. They can go for a mechanical valve, but it will require a life-long anti-coagulation therapy, which will significantly affect their quality of life. They can also opt for an artificial valve created from an animal tissue that can be used after a chemical treatment, or they can opt for a human donor valve. These will deteriorate over time and won’t last for more than 15 years.
But when the scientists tried out their “a-cellular” scaffold on sheep, they found that it gave birth to live cells within six months. Human trials have been taking place in Brazil for the last four years and the technology is expected to be available for human use in a few years.
A technology marvel that would be of enormous use is being attempted by the scientists in dental and bone care. The scientists have identified a peptide, a polymer produced when various amino acids found in the body come together, that can fight the decay of teeth, which are constantly attacked by acids. Exposure to acids leads to cavities. The scientists have found that the peptide, when applied in a liquid form by brush or as a mouthwash, can help create tiny three-dimensional structures that can fight tooth decay. Calcium, which is available through food, is naturally attracted by the peptide, creating a natural repair to the tooth. The scientists are hoping to extend the same technique for regeneration and repair of other soft and skeletal tissues such as blood vessels, bones and cartilage.
Fisher hopes that they may be able to develop at least 10 products over the next five years and halve the time required to get these products to market.
The new interventions will eventually be of immense value to India, which is also witnessing an increase in life expectancy. “Currently, 43 per cent of the global population of 80-plus people live in four countries including India,” says K.R. Gangadharan, founder of Heritage Hospital in Hyderabad and vice-president, International Federation on Ageing, a Canada-based non-profit organisation. Once the developments reach India, the aged may have the reason — and the joint — to do a jig.
Replacement body parts that never wear out could become a reality within a few years as the scientists say.
Dodgy knees and hips will be repaired using tissue engineering, while donor heart valves from animals are being specially treated to last indefinitely.
Longer-lasting artificial joints are already being tested in a bid to ensure people will be able to enjoy another 50 active years.
Unlike studies involving stem cells and growing ‘spare parts’ in a lab, the programme uses the body’s own regenerative systems. The Leeds scientists have developed a chemical wash that strips cells away from donated cartilage, heart valves, blood vessels and other tissue before they are put into a human body.
Research shows they become repopulated with cells within about six months. Some 40 patients have already been treated with modified heart valves in a study in Brazil.
Professor John Fisher, director of the institute and one of the world’s leading researchers into artificial joints, said research so far had shown the valves did not deteriorate and were not rejected by the body, because ‘foreign’ donor cells had all been stripped away.
The unique method of removing living cells from human and animal tissue creates a biological ‘scaffold’ that can be regenerated within the body, at the site which needs repairing.
Worn-out ligaments and cartilage in knees can be replaced with a scaffold that will eventually attract cells to make the joint last longer.
Other areas targeted for treatment are the spine – where discs can be replaced – elbow and shoulder tissues and parts of the knee. Vascular patches are being devised that seal the holes made in arteries when surgeons clear a blockage.
The technique is not suitjointsable for whole organs, however. Professor Fisher has also designed a ceramic-on-metal hip joint that reduces ten-fold the wear and tear on artificial joints.
As a result people should be able to get spare parts at an earlier age, when they are less disabled, and they could last up to 50 years, he said.
The professor added: ‘Hip have been used for nearly 50 years but nowadays people want to cycle, play tennis, even go skiing, so they have to last longer.’
He said a scaffolding transplant would cost only around £1,000 a time. It was much more expensive to grow cells outside the body, and there was a higher infection risk.
Professor Eileen Ingham, deputy director of the Institute, said stem cells were not the answer to structural replacement of wornout bits of the body such as heart valves.
She said: ‘We are working with the NHS National Blood & Transplant Tissue Services to apply it to human donor valves. Once a patient has one, it should last a lifetime.’
Professor Christina Doyle, chief executive of Xeno Medical, predicted that in 20-30 years there would be techniques capable of regenerating human tissue off-the-shelf for use in operations.
She said: ‘It will be a case of the surgeon dialling up for spare parts to be delivered in a sterilised plastic bag.’
In fact, Prof Williamson has prepared a list of 20 “lifespan essential” foodstuffs — all are rich in naturally occurring chemicals, known as polyphenols, which have been linked to a variety of health benefits, including protection against heart disease.
And, these foods and drinks could also help to slow down the ageing process by helping to protect cells from the natural damage that occurs over time, he has suggested.
Prof Williamson said: “Epidemiology studies support the protective effects of polyphenol-rich foods. Lack of these components in the diet because of low intake of fruit and vegetables, increases the risk of chronic disease.
“This means that they are essential to fulfil the maximum individual lifespan, and so I propose that they are ‘lifespan essential’.
“Although they might not be essential for growth and development or the maintenance of major body functions, there is increasing knowledge concerning their potential for health maintenance or disease risk reduction throughout adulthood and during ageing.”
Even a recent study carried out by scientists in the US, Britain and Australia concluded that polyphenols can help protect against heart disease.
Diagnosis of life-threatening diseases such as cancer may become a matter of minutes as scientists have developed a new bio-sensor technology, which they claim provides results within 15 minutes.
“The technology uses antibodies to detect biomarkers — molecules in the human body which are often a marker for disease — much faster than current testing methods,” said co-researcher Paul Millner from the Faculty of Biological Sciences at the University of Leeds.
The researchers are hopeful that the technology could be developed into a small device similar to a mobile phone into which different sensor chips could be inserted, depending on the disease being tested for.
“We’ve designed a simple instrumentation,” Millner said, “which will make the bio-sensors easy to use and understand. They’ll work in a format similar to the glucose bio-sensor testing kits that diabetics currently use.”
Currently, blood and urine samples are tested for disease markers using a three-decade-old method called ELISA (Enzyme Linked Immunosorbant Assay). The method, considered costly, takes more than two hours to complete and requires technical expertise.
“The new technology could be used in doctors’ surgeries for more accurate referral to consultants and in hospitals for rapid diagnosis,” he said.
Tests have shown that the bio-sensors can detect a wide range of diseases, including prostate and ovarian cancer, stroke, multiple sclerosis, heart disease and fungal infections. It also hold prospects for testing tuberculosis and HIV, the researcher claimed.
The technology was developed through a European collaboration of researchers and commercial partners in a project called ELISHA.