Glaucoma is a condition that arises when there's too much pressure in eye. Long term pressure damages the optic nerve and consequently impairs sight. The condition is inherited so it is important to get it checked. Glaucoma is very easy to spot and treat by controlling pressure in the eye. Many people compensate and don't even realise they have it.

- Huseyin - This is one of the problems, in an ideal world, that stem cells would be able to rectify. Scientists have used animal models of retinal damage and injected stem cells into the eye of mice with retinal damage. By labelling it with Green Fluorescent Protein, we can find out where they've gone. In many cases cells have been found in the retina, but we don't know if the animals can really see better. All we know is that electrical transmission in the nerves is better. One method used to test whether mice have improved sight is to test one of their natural responses. If mice have a light shone on them, they freeze and stay very still. However, we want to know if the treatment is better than being able to respond to light or dark, although any improvement would be better. Again, it is important to stress that it's very early days for stem cell treatment. The possibility is there, but we have to be realistic. There are already experiments with Parkinson's disease using foetal tissue which have been very successful. China is a big country for stem cell research and they are reporting some success. However, it is still too early to put vast NHS resources into this technology. I would rather invest in the basic building blocks of knowledge and then move up to experimental models. Only after that can we try experiments in humans. We need to be able to reproduce it on a basic level first. I refuse to put a date on it, but I suppose 15 to 20 years might be realistic.

- Roger - The idea is like creating a retinal implant. We think that's many years away. We are trying to apply the knowledge people have of the development of retinal cells in animals and make it work in the petri dish.

 

- Roger - I dare say we have stem cells in our bodies throughout our lives. We need stem cells on parts of our body that get worn out quickly and thus need replacing all the time. The skin is an example of this. We need to work out how to make these stem cells work better. By and large, specialised cells stop dividing once thy have finished their specialisation.

- Huseyin - The problem with the brain is that even though we know the stem cells are there and that they are kicked into action when there is damage, there aren't enough of them. If there were, people would be able to get better if they have a brain disease or brain trauma. Specialised brain cells just don't have the capacity to divide again.

 

Vitiligo is a de-pigmented patch on the skin. It occurs where the immune system has destroyed a patch of melanocytes which are the cells that produce the dark pigement melanin, which mops up UV light from the sun. Michael Jackson claims he has this disease. It's possible, though unlikely at the moment that stem cells could be used to repopulate skin that has lost its melanocytes.

 

- Roger - This is one of our key objectives. One of the biggest frustrations is that we can't say when we will have a cure. Hopefully we will have clinical trials in five to ten years, but it could be two to three times that.

- Chris - You might be aware of some grafts of pancreatic cells in Canada. They have grafted cells from people who have died, isolated the important cells and put them back into people with diabetes. This has had some good success. Eyelet cell transplants like this do not come from stem cells but from people who donate their pancreas after they die. There are side effects to the grafts because the immune system will attack it as foreign material. To stop this rejection, you need to turn off immune system. This can be bad, and so these grafts are only given to people who have very bad diabetes and might die otherwise.

- Huseyin - I would just like to give you some bullet points. Firstly, it is quite clear that we can make insulin secreting cells in the dish. It has been done with both types of stem cells. It has not been fully accepted that we have pancreatic stem cells, but embryonic stem cells can give rise to insulin cells. Secondly, the issue of transplantation is a very important one. Of the very small amounts of stem cells injected into animals and human, few actually survive. The surprising fact is that those cells cure in many cases, so you don't seem to need too many stem cells to survive to have an effect. Thirdly, the immune system might still attack the stem cells. If you have an immune disease that attacks the pancreas, it is just as likely that it will still attack the pancreas even after treatment. There's a lot more work to be done, but I think the study in Canada is very encouraging. Patients should take heart from that.

 

Plant cell walls are made from cellulose, the woody stuff in trees. So when you saw down a tree, you are sawing down cellulose and lignin. If you look down a microscope, what you see is brick-shaped cells. The outermost part of each cell is the cell wall, and inside that is the cell membrane. Sometimes the outside can be lignified, which makes the cell stiff so plants can stand up straight. It's also how you make paper. All the cellulose and woody bits from the plant cell wall are the fibres you see in paper.

 

There is evidence in animals that you can get improved cardiac output afterwards. The stem cells might give rise to new heart muscle cells, or promote the growth of new blood vessels which improve blood supply to the heart muscle, helping it to work more efficiently.

 

 

 

It's False - The rate of acceleration of a jumping flea is actually 20 times greater than the space shuttle during launch.

It's True - In November budding testicle chefs gathered in Savinac, Serbia, to see who could cook the tastiest dish out of bull's and boar's testicles. Next year the competition will include an 'exotic' category in which chefs will have to knock up nosh from ostrich and camel privates…

It's True - The lion's mane, our largest known jellyfish, can reach 8 feet across and produce tentacles 200 feet long.

It's True - Given their huge size it's probably just as well !

It's False - You'd actually need to scream for 8 and a half years to produce enough energy to heat up a cup of coffee.

It's True - The 65 metre wingspan of a Boeing 747 is almost twice the length of the Wright Brother's first successful flight in 1903 which achieved a flight time of 12 seconds and covered 37 metres !

It's False - It's actually much faster - 80 times per second. They're also the only birds to be able to fly in any direction, including backwards.

It's False - Not quite, that's the amount you'd burn up on a stiff jog, but vacuuming and household chores do consume a lot of energy - dusting and polishing uses about 150 calories an hour and shoving the Hoover round uses up 210.

It's True - The Logitech io contains real ink and writes normally but also reads what you write and stores up to 40 pages in memory which can be transferred to a computer where software converts it into computer-readable text. Not guaranteed for doctors use though !

It's True - Harold Craighead and Dustin Carr from Cornell University, New York, produced the world's smallest Fender Stratocaster in 1997. It has 6 strings about 100 nanometres, or 50 atoms, wide and at 10 micrometres long would fit inside one of our body's cells.

It's False - The telescope, which was launched in 1990, is actually orbiting about 375 miles above the Earth. As well as helping us to discover 100 new planets and understand a bit more about the expansion of the universe and the birth and death of stars, it's also the first satellite designed to be 'serviced' - on several occasions space-walking astronauts have replaced worn out or outdated parts, including correcting a fault with the main mirror.

It's True - Thompson Holidays has installed a system that offers would-be tourists the sights and smells of Egypt including the spices in the market and the musty aroma of a pharoah's tomb. Thompson says the new service allows customers to 'try before they buy'.