University of Sheffield

Male contraceptive jab almost 100 per cent effective… and it can increase libido

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A contraceptive injection for men has been shown to be almost 100 per cent effective, and may also increase libido.

The hormone-based jab is designed to lower sperm counts by acting on the brain’s pituitary gland.

Over a year-long trial, nearly 96 per cent of couples relying on the injection to prevent unplanned pregnancies found it to be effective. During this time, only four pregnancies occurred among the men’s partners.

 However, researchers said more work was needed to address the treatment’s reported side effects, which included depression and other mood disorders, muscle pain and acne. However it did also increase libido.

Dr Mario Festin, from the World Health Organisation in Geneva, Switzerland, said: “The study found it is possible to have a hormonal contraceptive for men that reduces the risk of unplanned pregnancies in the partners of men who use it.

“Our findings confirmed the efficacy of this contraceptive method previously seen in small studies.”

The contraceptive was found to be 96 per cent effective during 12 month trials 
The contraceptive was found to be 96 per cent effective during 12 month trials 

The injections contained a long-acting form of progestogen, a hormone that has the effect of blocking sperm production controlled by the pituitary gland.

Nearly 300 men were given injections every two months, which reduced sperm count to one million per millilitre or fewer within 24 weeks. At the end of the trial, three-quarters of the men said they would be willing to continue using the contraceptive jab.

Prof Allan Pacey at the University of Sheffield said: “There is certainly an unmet need for an effective reversible contraceptive for men, along the lines of the hormonal contraceptive for women.

“However, none of the preparations that have been developed and tested to date have managed to become a commercial reality for one reason or another.

“In this latest study, the authors used a combination of hormones (progesterone and testosterone) to try and take the science forward. Using long-acting injectable forms of these hormones they were able to suppress the production of sperm to a remarkable degree. As such, this contraceptive was extremely effective and therefore certainly has promise.

“However, the fact that so many side effects were observed in the men who were taking part in the trial is of concern. For a male contraceptive to be accepted by men (or women) then it has to be well tolerated and not cause further problems.”

Source: Journal of Clinical Endocrinology & Metabolism

New research could lead to restoring vision for sufferers of retinal disorders

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New research could lead to restoring vision for sufferers of retinal disorders
Fly brain diagram.

Engineers and neuroscientists at the University of Sheffield have demonstrated for the first time that the cells in the retina carry out key processing tasks. This could pave the way for improving retinal implants and therefore the sight of thousands of people suffering from retinal disorders.

 Up to now, it was thought that the function of these retinal cells, or photoreceptors, was mainly to convert light into electrical signals, from which the brain can interpret images.

However, the new research from Sheffield, published in the journal PLOS ONE, shows that in fruit flies, the photoreceptors believed to be involved in motion detection play a key role in providing visual information about the world around us.

The similarities that exist between responses of human cone photoreceptors and fly photoreceptors suggest that the human eye processes visual signals in a similar way.

If this were true, the research could have significant implications for those developing for patients with retinal disorders such as macular degeneration. Age-related macular degeneration is the most common cause of sight loss in the developed world and currently affects more than 600,000 people in the UK.

Retinal implants replace damaged or dead cells by converting light into electrical signals that are sent to the brain. The implants do not restore vision completely but can help patients to detect patterns and shapes.

Daniel Coca, lead researcher from Sheffield’s Department of Automatic Control and Systems Engineering, said: “We think that implementing the processing tasks performed by photoreceptors into retinal implants could help the brain accomplish key tasks such as object recognition and motion detection. This could significantly improve the performance of artificial retinas and therefore the sight of thousands of people suffering from macular degeneration.”

Male pill keeps sperm ‘in storage’

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Sperm

The prospect of a “male pill” that would let men enjoy a full sex life with no chance of getting a woman pregnant has moved a step closer.

Scientists in Australia have found a reversible way to stop sperm getting into the ejaculate, without affecting sexual function.

The animal tests showed the sperm could be “kept in storage” during sex.

The findings were published in the journal Proceedings of the National Academy of Sciences.

The quest for the male contraceptive pill has largely focused on getting men to produce non-functional sperm.

But some drugs used for this purpose “have intolerable side-effects,” said Dr Sabatino Ventura, one of the researchers at Monash University.

Drugs can induce infertility, but they may also affect sexual appetite or cause permanent alterations to sperm production.

Sperm stores

The team at Monash used a different approach. Normally, the sperm is moved out of the vas deferens storage area in the testes just before ejaculation.

The group produced genetically modified mice that were unable to squeeze the sperm out of the vas deferens.

Dr Ventura told the BBC: “The sperm stay in the storage site so when the mice ejaculate there’s no sperm and they are infertile.

“It is readily reversible and the sperm are unaffected, but we need to show we can do this pharmacologically, probably with two drugs.”

So far the research group has made the mice infertile by changing their DNA to stop them producing two proteins needed to move the sperm.

The researchers now need to find a pair of drugs that can produce the same effect. They believe one has already been developed and has been used for decades in patients with benign prostate enlargement.

However, they would have to work from scratch to find the second one – a process that could take a decade.

The proteins targeted also have a role in controlling blood vessels; so there could be side-effects on blood pressure and heart rate.

However, in the mice at least, the researchers detected only a “very slight” drop in blood pressure. There could also be an impact on the volume of ejaculate.

Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield , told the BBC: “It’s a very good study, almost like a biological vasectomy in [that] it stops the sperm coming out.

“It’s a good idea; they need to get on with it and see what it does in people.”

Army robot refuses to be pushed over.

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Meet Atlas, a humanoid robot capable of crossing rough terrain and maintaining its balance on one leg even when hit from the side.

And WildCat, the four-legged robot that can gallop untethered at up to 16mph (26km/h).

These are the latest creations of Boston Dynamics, a US robotics company part-funded by the Defense Advanced Research Projects Agency (Darpa).

The robots are part of Darpa’s Maximum Mobility and Manipulation programme.

Darpa says such robots “hold great promise for amplifying human effectiveness in defence operations”.

Referring to Atlas’s ability to remain balanced despite being hit by a lateral weight, Noel Sharkey, professor of Artificial Intelligence and Robotics at the University of Sheffield, told the BBC: “This is an astonishing achievement… quite a remarkable feat.”

This version of Atlas is one of seven humanoid robots Boston Dynamics is developing in response to the Darpa Robotics Challenge.

In December, competing robots will be set eight tasks to test their potential for use in emergency-response situations, including crossing uneven ground, using power tools and driving a rescue vehicle.

Darpa wants to improve the manoeuvrability and controllability of such robots while reducing manufacturing costs.

WildCat strike?

Boston Dynamics puts its WildCat robot through its paces

WildCat can bound, gallop and turn, mimicking the movements of quadruped animals. It is powered by an internal combustion engine.

“It is a shame that such technology is not being developed with other research funding,” said Prof Sharkey, who is also chair of the International Committee for Robot Arms Control.

“We do not know what military purpose it will serve but certainly it is a step towards a high-speed ground robot that could be weaponised to hunt and kill.”

The video shows WildCat performing on a flat surface, but Prof Sharkey said: “It would be good to see how well it could perform in a muddy field.”

Last year, Boston Dynamics’ Cheetah robot reached a sprint speed of 28.3mph tethered to a treadmill.

Geoff Pegman, managing director of RURobots, told the BBC: “Robotics has been making important strides in recent years, and these are a couple of demonstrations of the technology moving forward.

“However, their application may be limited to areas such as defence and, maybe specialised construction or demolition tasks.

“In other applications there are more efficient ways of achieving the mobility more cost effectively.”

Pentagon-funded Atlas robot refuses to be knocked over.

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Boston Dynamics road-tests its Atlas robot on rough terrain

Meet Atlas, a humanoid robot capable of crossing rough terrain and maintaining its balance on one leg even when hit from the side.

And WildCat, the four-legged robot that can gallop untethered at up to 16mph (26km/h).

These are the latest creations of Boston Dynamics, a US robotics company part-funded by the Defense Advanced Research Projects Agency (Darpa).

The robots are part of Darpa’s Maximum Mobility and Manipulation programme.

Darpa says such robots “hold great promise for amplifying human effectiveness in defence operations”.

Referring to Atlas’s ability to remain balanced despite being hit by a lateral weight, Noel Sharkey, professor of Artificial Intelligence and Robotics at the University of Sheffield, told the BBC: “This is an astonishing achievement… quite a remarkable feat.”

This version of Atlas is one of seven humanoid robots Boston Dynamics is developing in response to the Darpa Robotics Challenge.

In December, competing robots will be set eight tasks to test their potential for use in emergency-response situations, including crossing uneven ground, using power tools and driving a rescue vehicle.

Darpa wants to improve the manoeuvrability and controllability of such robots while reducing manufacturing costs.

WildCat strike?

Boston Dynamics puts its WildCat robot through its paces

WildCat can bound, gallop and turn, mimicking the movements of quadruped animals. It is powered by an internal combustion engine.

“It is a shame that such technology is not being developed with other research funding,” said Prof Sharkey, who is also chair of the International Committee for Robot Arms Control.

“We do not know what military purpose it will serve but certainly it is a step towards a high-speed ground robot that could be weaponised to hunt and kill.”

The video shows WildCat performing on a flat surface, but Prof Sharkey said: “It would be good to see how well it could perform in a muddy field.”

Last year, Boston Dynamics’ Cheetah robot reached a sprint speed of 28.3mph tethered to a treadmill.

Geoff Pegman, managing director of RURobots, told the BBC: “Robotics has been making important strides in recent years, and these are a couple of demonstrations of the technology moving forward.

“However, their application may be limited to areas such as defence and, maybe specialised construction or demolition tasks.

“In other applications there are more efficient ways of achieving the mobility more cost effectively.”

Warning of three-person IVF ‘risks’

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Concerns about the safety of a pioneering therapy that would create babies with DNA from three people have been raised by researchers.

_69959209_c0104965-ivf_embryo,_light_

The advanced form of IVF could eliminate debilitating and potentially fatal mitochondrial diseases.

Writing in the journal Science, the group warned that the mix of DNA could lead to damaging side-effects.

The expert panel that reviewed the safety of the technique said the risks described would be “trivial”.

The UK is leading the world in the field of “mitochondrial replacement”. Draft regulations to allow the procedure on a case-by-case basis will be produced this year and some estimate that therapies could be offered within two years.

“Start Quote

One of our prime interests is about the safety of these techniques.”

Prof Doug Turnbull Mitochondrial replacement researcher

Mitochondria are the tiny, biological “power stations” that provide nearly every cell, which make up the body, with energy. They are passed from a mother, through the egg, to her child.

But if the mother has defective mitochondria then it leaves the child starved of energy, resulting in muscle weakness, blindness and heart failure. In the most severe cases it is fatal and some families have lost multiple children to the condition.

The proposed therapy aims to replace the defective mitochondria with those from a donor egg.

Continue reading the main story

Method one: Embryo repair 1) Two eggs are fertilised with sperm, creating an embryo from the intended parents and another from the donors 2) The pronuclei, which contain genetic information, are removed from both embryos but only the parents’ is kept 3) A healthy embryo is created by adding the parents’ pronuclei to the donor embryo, which is finally implanted into the womb

Continue reading the main story

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But mitochondria have their own DNA, albeit a tiny fraction of the total. It means a baby would have genetic information from mum, dad and a second woman’s mitochondria.

The concerns raised – by scientists at the University of Sheffield, the University of Sussex and Monash University in Australia – are about a poor match between the mitochondrial DNA and that from the parents.

The woman who lost all her children

Sharon Bernardi and her son Edward, who died last year aged 21

Every time Sharon Bernardi became pregnant, she hoped for a healthy child.

But all seven of her children died from a rare genetic disease that affects the central nervous system – three of them just hours after birth.

When her fourth child, Edward, was born, doctors discovered the disease was caused by a defect in Sharon’s mitochondria.

Edward was given drugs and blood transfusions to prevent the lactic acidosis (a kind of blood poisoning) that had killed his siblings.

Five weeks later Sharon and her husband, Neil, were allowed to take Edward to their home in Sunderland for Christmas – but his health slowly began to deteriorate.

Edward survived into adulthood, dying in 2011 at the age of 21.

Now Sharon is supporting medical research that would allow defective mitochondria to be replaced by DNA from another woman.

They said there was an interaction between the DNA in the mitochondria and the rest which is packaged in a cell’s nucleus.

Their studies on fruit flies suggested that a poor match of genetic information between the nucleus and mitochondria could affect fertility, learning and behaviour.

“Describing it as like changing the batteries in a camera is too simplistic,” Dr Klaus Reinhardt from the University of Sheffield told the BBC.

He added : “It is not at all our intention to be a roadblock, we think it is fantastic that for women affected there could be a cure.

“We have pointed out one or two points which need to be looked at.”

‘Trivial’

The Human Fertilisation and Embryology Authority, which regulates fertility treatment in the UK, commissioned a review into the safety of the technique.

Prof Robin Lovell-Badge, who was on the review panel, disagreed. He said humans had diverse mitochondrial and nuclear DNA, so any consequences of poor matches would have already become apparent.

He told the BBC news website: “Humans are breeding between races and producing healthy children all the time. If there is an effect then it must be very trivial as it’s not been noticed.”

He has called for further safety testing, such as research into the risks posed by any defective mitochondria which might still be passed onto a child.

Prof Doug Turnbull, who is developing the mitochondrial replacement therapy at Newcastle University, insisted: “One of our prime interests is about the safety of these techniques.

“It’s perfectly reasonable to draw some of these concerns, I just don’t share the same concerns.

“Mismatch between the mitochondrial and nuclear genome is a potential risk, but I don’t think it’s personally as big a risk as they’re saying.”

Mitochondrion
Hundreds of mitochondria in every cell provide energy

The idea has also raised ethical concerns from groups concerned about the impact of altering human genetic inheritance.

In a statement, the Human Fertilisation and Embryology Authority said: “The panel of experts convened by the HFEA to examine the safety and efficacy of mitochondria replacement carefully considered the interaction between nuclear and mitochondrial DNA and concluded that the evidence did not show cause for concern.

“As in every area of medicine, moving from research into clinical practice always involves a degree of uncertainty. Experts should be satisfied that the results of further safety checks are reassuring and long term follow-up studies are crucial.

“Even then patients will need to carefully weigh up the risk and benefits for them.”

FAQ:A user’s guide to nanotechnology.

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All FAQs have been provided by University of Sheffield


1. What is nanotechnology?

Nanotechnology is an area of Science that is concerned with the control and manipulation of matter on the molecular scale. This scale is often measured in nanometres, hence the nano in nanotechnology.

http://www.bbc.co.uk/news/science-environment-10937566 

nanochip

2. How small is a nanometre?

If you take an average 4 year old child with a height of 1m and then shrink them by a factor of 1000, they would then be the size of an ant (or a millimetre). If you shrink them again by a factor of 1000, they would be the size of a red blood cell (or a micrometre). We need to shrink them once more by a factor of 1000 to reach a scale measured in nanometres.

3. What is the science behind Catalytic Clothing?

Catalytic Clothing harnesses the power of a photocatalyst to break down air borne pollutants. A catalyst is a term used to describe something that makes a reaction proceed at a greater rate but isn’t actually consumed during that reaction. A photocatalyst gains the energy it needs to be active from light.

4. Where do the pollutants come from?

The two biggest sources of air borne pollutants are industry and motor vehicles. Although the majority of the pollutants are prevented from reaching the air, using technology such as catalytic converters, some do escape. It is these pollutants that Catalytic Clothing will break down.

5. How are the pollutants broken down?

When the light shines on the photocatalyst, the electrons in the material are rearranged and they become more reactive. These electrons are then able to react with the water in the air and break it apart into 2 radicals. A radical is an extremely reactive molecule. These radicals then react with the pollutants and cause them to break down into non-harmful chemicals.

6. What happens to the pollutants after they’ve been broken down?

The Catalytic Clothing technology is designed to breakdown the pollutants straight away. However, some pollutants may become attached without being broken down. In this case, the pollutants will be washed off during subsequent laundering. This actually already happens with normal clothing.

7. Is this technology used in any other products?

Photocatalysts have been incorporated into several commercially available products that possess de-polluting properties. These products include paints, cements and paving stones.

8. How is the technology delivered to the surface of the clothing?

The photocatalyst is delivered to the surface of the clothing during the traditional laundry procedure as an additive within a standard product such as a fabric conditioner. The active agent is packaged within a shell that is attracted towards, and subsequently binds to, the surface of the clothing during the washing cycle.

9. Why do we need mass participation to produce a noticeable reduction in the level of pollution?

Although any garment that is treated with the product becomes active, a single garment is only able to remove a small proportion of the air borne pollutants. Therefore, a large number of individuals, all acting together, is required to produce a noticeable reduction in the level of pollution.

10. How many people would need to participate to produce a noticeable reduction in the level of pollution?

An estimate of the required level of uptake for the Catalytic Clothing indicates that a significant reduction in the level of air borne pollutants in a large city such as London could be achieved if, for every metre of pavement width, 30 people wearing Catalytic Clothes walked past each minute.

11. Would someone wearing Catalytic Clothing be at a greater risk of exposure to pollutants?

No. The Catalytic Clothing technology won’t actively attract any pollutants. Instead, it will break down anything that comes within very close proximity of the photocatalyst’s surface.

12. How would society benefit if Catalytic Clothing was widely introduced?

Exposure to air borne pollutants presents a risk to human health and also has a detrimental effect on ecosystems and vegetation. Air pollution is currently estimated to reduce the life expectancy of every person in the UK by an average of 7-8 months. The widespread introduction of Catalytic Clothing would dramatically reduce the level of air borne pollutants, thereby improving the quality of life for all members of society.

13. Can any material be used? 

Each type of material will need to be tested separately for efficacy and adhesion, but it is our aim to make this technology deliver to all fabric types eventually. We have started with one of the most commonly used materials, cotton. 

14. What will be the cost of using this domestically?

It is hard to say at this stage and will depend on whether it ends up as an additive, or a product in its own right. As mass use will have the most impact on air quality, clearly the cost has to be as competitive as possible.

15. Are there any “down sides”? 

We will discover these as the research continues and try to create solutions as we go.

16. How can you reassure people that it will be safe?

The product will go through full life cycle analysis as any other new product being brought to market. All H&S aspects will be independently validated and just like a new medicine, or new skin care product, all the usual legal requirements will be met ahead of the product reaching the supermarket shelves.

17. When might it be available? 

We are aiming for two years if all goes to plan!

18. How can you tell if it’s working?

Most major cities and towns have some from of air quality monitoring stations already in place. Those monitors record the levels of a range of major pollutants, such as NOx and VOC’s. We expect that once the Catalytic Clothing technology is in widespread use, considerable reductions in the levels of the pollutants will be observed using those monitors. Anecdotal evidence also says that people notice that it’s easier breathe when photocatalytic products are used.

19. Is it measurable? 

Yes (see above)

20. How has the technology been applied to the first generation products: Herself, and Field of Jeans?

The TiO2 was sprayed on to the garments.

21. What is the Herself dress made of? What are the blue parts – they look like paint?

The fabric of the dress is coated with titania loaded cement and the blue colour is dye.

22. What pollutants can the chemical absorb? 

Nothing is absorbed but the photocatalyst causes oxidation of substances adsorbed on the surface.  Nitrous oxide is converted to soluble nitrate and volatile organics are converted into fatty acids and soaps.

23. How much air space can they purify? (Or a quantifiable measurement of how much air is purified)

The air (or the dress) have to be moving – if they are moving quickly enough then 1 square meter of coated fabric can take out 0.5 g of NOx per day.

24. Does the Herself dress have catalytic nano particles or is it a photocatalyst? Can we get a clarification on the process, which pollutants break down? Does this mean that the dress only works in daylight?

The nanoparticles on the dress are a photocatalyst. The size of the particles is important.  The coating only works in the presence of light and oxygen.  It doesn’t need to be sunlight – interior lights work too.

25. Will all pollutants become instantly broken down or will some remain? 

Not all pollutants are broken down and some remain.

26. Will there be any build up of Tio2 in the water supply? 

Particles that escape the washing machine will enter the waste water system. TiO2 is an inert, white mineral, and only an effective photocatalyst when it is in the form of nanoparticles that can see light. Any escaping particles are most likely in a mass or group already and will definitely form into groups in the water treatment process, aided by its flocculation process. (The flocculation process forms or causes to form substances into small clumps or masses, – a process, which helps to remove “solids”). Some water treatment systems use UV but these are not widespread. Any titania below a couple of mm of water won’t be particularly active because the UV level will be low as will the Oxygen concentration, in other words because it is too dark there will be little catalytic activity. Any TiO2, which enters the waste water system, will be minimal and harmless and will be extracted by the flocculation process as described above.
Source: catalytic-clothing.org

Life created from eggs made from skin cells.

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Stem cells made from skin have become “grandparents” after generations of life were created in experiments by scientists in Japan.

The cells were used to create eggs, which were fertilised to produce baby mice. These later had their own babies.

If the technique could be adapted for people, it could help infertile couples have children and even allow women to overcome the menopause.

But experts say many scientific and ethical hurdles must be overcome.

Healthy and fertile

Stem cells are able to become any other type of cell in the body from blood to bone, nerves to skin.

Last year the team at Kyoto University managed to make viable sperm from stem cells. Now they have performed a similar feat with eggs.

They used stem cells from two sources: those collected from an embryo and skin-like cells which were reprogrammed into becoming stem cells.

The first step, reported in the journal Science, was to turn the stem cells into early versions of eggs.

A “reconstituted ovary” was then built by surrounding the early eggs with other types of supporting cells which are normally found in an ovary. This was transplanted into female mice.

Surrounding the eggs in this environment helped them to mature.

IVF techniques were used to collect the eggs, fertilise them with sperm from a male mouse and implant the fertilised egg into a surrogate mother.

Dr Katsuhiko Hayashi, from Kyoto University, told the BBC: “They develop to be healthy and fertile offspring.”

Those babies then had babies of their own, whose “grandmother” was a cell in a laboratory dish.

Devastating blow

The ultimate aim of the research is to help infertile couples have children. If the same methods could be used in people then cells in skin could be turned into an egg. Any resulting child would be genetically related to the mother.

However, Dr Hayashi said that was still a distant prospect: “I must say that it is impossible to adapt immediately this system to human stem cells, due to a number of not only scientific reasons, but also ethical reasons.”

He said that the level of understanding of human egg development was still too limited. There would also be questions about the long-term consequences on the health of any resulting child.

Dr Evelyn Telfer, from the University of Edinburgh, said: “It’s an absolutely brilliant paper – they made oocytes [eggs] from scratch and get live offspring. I just thought wow! The science is quite brilliant.”

However, she warned that this had “no clinical relevance” as there were still too many gaps in understanding about how human eggs developed.

“If you can show it works in human cells it is like the Holy Grail of reproductive biology,” she added.

Prof Robert Norman, from the University of Adelaide, said: “For many infertile couples, finding they have no sperm or eggs is a devastating blow.

“This paper offers light to those who want a child, who is genetically related to them, by using personalised stem cells to create eggs that can produce an offspring that appears to be healthy.

“It also offers the potential for women to have their own children well past menopause raising even more ethical issues.

“Application to humans is still a long way off, but for the first time the goal appears to be in sight.”

Dr Allan Pacey, from the British Fertility Society and the University of Sheffield, said: “What is remarkable about this work is the fact that, although the process is still quite inefficient, the offspring appeared healthy and were themselves fertile as adults.”

Source:BBC