- Viruses could kill superbugs that antibiotics can't
- Brain works best when cells keep right rhythms
- World first: Chinese scientists create pig stem cells
- Stem cells cultured on contact lens 'restore sight'
- Bone-repairing stem cell jab hope
- Egg stem cells could revolutionise fertility treatment
- Immune system taught to fight deadly skin cancer
- Synthetic Fibers to Reverse Blindness
Viruses could kill superbugs that antibiotics can't
- 23 April 2009 by Catherine de Lange
A VIRUS that gobbles up the bacteria that cause debilitating ear infections could become the next weapon against antibiotic-resistant bacteria, after the first clinical trial of a bacteriophage treatment proved successful.
The trouble with bacteria is that they can evolve to outsmart antibiotics, secreting enzymes that break them down, or developing extra pumps to force drugs out of their cells. Because antibiotic resistance hampers treatment for common diseases including pneumonia, salmonella and tuberculosis, it is a growing public health problem.
Pseudomonas aeruginosa, which can cause ear infections, is particularly hard to treat because it wraps itself in a biofilm - a layer of sugars and proteins that make it up to 1000 times as resistant to antibiotics as a non-biofilm from the same species.
Now a single dose of Biophage-PA, which contains a virus that selectively attacks P. aeruginosa, has successfully treated long-term sufferers of antibiotic-resistant ear infections.
The therapy's key ingredients are viruses called bacteriophages. These "eaters of bacteria" break down the biofilm and destroy target cells, without harming other useful bacteria in the body.
Andrew Wright from University College London Ear Institute and colleagues studied 24 people with severe ear infections (Clinical Otolaryngology, accepted for publication). Half the volunteers were given Biophage-PA and the rest received a placebo.
Pain, pus secretion and inflammation were reduced in both groups, but the change was twice as noticeable in the group on the treatment. The number of target bacteria in the ear was significantly reduced in this group, while there was no significant reduction in the placebo group. By the end of the six-week trial, three patients on the phage were clear of infection.
There are other advantages too, says Harper. You only need to give one dose, unlike regular courses of antibiotics which people sometimes forget to finish, making resistance more likely. Standard antibiotics can also damage hearing by destroying delicate hairs in the ears needed to transmit sound. source
My comment: Wonderful news! As a pneumonia-prone person, I think this is a great advance, though there's always a question mark on virus employing drugs. Because if the bacteria can learn how to avoid antibiotics, it may figure out how to avoid viruses too. And would this adaptation be healthy enough for our body? Sure, there is only one way to find it out. Still, I think that this is a wonderful opportunity to learn more about bacteria and viruses and to find a while to cure people along the way. Nice!
Brain works best when cells keep right rhythmsApril 26th, 2009
It is said that each of us marches to the beat of a different drum, but new Stanford University research suggests that brain cells need to follow specific rhythms that must be kept for proper brain functioning. These rhythms don't appear to be working correctly in such diseases as schizophrenia and autism, and now two papers due to be published online this week by the journals Nature and Science demonstrate that precisely tuning the oscillation frequencies of certain neurons can affect how the brain processes information and implements feelings of reward.
The new findings suggest that, like the cells that keep the beat of the heart (or the coxswain on a rowing team that calls out the rhythm of the strokes), certain brain cells can orchestrate oscillations that ultimately help govern behavior of other cells that are guided by those rhythms.
In the Nature study, which will be published online April 26 along with a companion paper from MIT on which Deisseroth and graduate student Feng Zhang are also authors, Deisseroth's team focused on neurons in mice that produce a protein called parvalbumin. Some researchers have suspected that these neurons drive "gamma" brain waves that oscillate at a frequency of 40 times a second (or Hertz). These waves, according to the hypothesis, might affect the flow of information in the brain. To date this could never be proved because no one could selectively control the neurons and see the resulting effect on the information flow, or oscillations.Desisseroth's group has developed a technique, called optogenetics, in which specific cells can be genetically engineered to be controlled by pulses of visible light. The team did this with parvalbumin neurons in mice and found that by exciting or inhibiting them, they could produce or suppress "gamma" waves and see a marked change in the "bit rate" or quantity of information flowing through brain circuits.
"What we found is that if you crank the parvalbumin neurons down, you see fewer of these 40-Hertz oscillations. If you crank them up you see more of these gamma oscillations," Deisseroth said. "That's the first real proof that these neurons are indeed involved in generating these gamma brain waves.
Deisseroth added: "The final outcome of this is that parvalbumin neurons and gamma oscillations work together to enhance the flow of real information in the brain."
The potential link to disease comes from the fact that in autism the gamma oscillations appear to be present at the wrong intensity, while in schizophrenia there appear to be too few parvalbumin neurons.
"This is a new perspective relevant to both schizophrenia and autism, conditions in which information comes in but it isn't necessarily processed correctly," Deisseroth said.
In the Science paper, which will be published first online April 23 in Science Express, Deisseroth led a team of researchers at Stanford and the University of California-San Francisco in investigating the effect of controlling the oscillations of neurons that emit the brain chemical dopamine. The group, made up of neuroscience, bioengineering and psychiatry researchers, found that varying the oscillations led freely-behaving mice to sense varying levels of reward.
In some sense, the papers suggest that people who aren't thinking clearly or feeling happy might just be out of step, or rather have brain cells that quite literally don't have rhythm. source
My comment: Another wonderful piece of research. And it has more than one implication. From the one side, it really shed light on the autism and schizophrenia as two sides of one problem-wrong rhythms of gamma brain waves. I wonder if then this two conditions can be regulated by neural beats which usually provoke different brain wave states. Or maybe they cannot get into those states at all, if the neurons are completely abnormal. The other side of the story is that obviously this research backs the whole thing with brainwave beats and so on, since there is so heavy correlation between the state of the brain (as in brainwaves) and the information processing. Very very nice!
World first: Chinese scientists create pig stem cellsJune 2nd, 2009
Scientists have managed to induce cells from pigs to transform into pluripotent stem cells - cells that, like embryonic stem cells, are capable of developing into any type of cell in the body. It is the first time in the world that this has been achieved using somatic cells (cells that are not sperm or egg cells) from any animal with hooves (known as ungulates).
The implications of this achievement are far-reaching; the research could open the way to creating models for human genetic diseases, genetically engineering animals for organ transplants for humans, and for developing pigs that are resistant to diseases such as swine flu.
Dr Xiao, who heads the stem cell lab at the Shanghai Institute of Biochemistry and Cell Biology (Shanghai, China), and colleagues succeeded in generating induced pluripotent stem cells by using transcription factors to reprogramme cells taken from a pig's ear and bone marrow. After the cocktail of reprogramming factors had been introduced into the cells via a virus, the cells changed and developed in the laboratory into colonies of embryonic-like stem cells. Further tests confirmed that they were, in fact, stem cells capable of differentiating into the cell types that make up the three layers in an embryo - endoderm, mesoderm and ectoderm - a quality that all embryonic stem cells have. The information gained from successfully inducing pluripotent stem cells (iPS cells) means that it will be much easier for researchers to go on to develop embryonic stem cells (ES cells) that originate from pig or other ungulate embryos.Dr Xiao said: "Pig pluripotent stem cells would be useful in a number of ways, such as precisely engineering transgenic animals for organ transplantation therapies. The pig species is significantly similar to humans in its form and function, and the organ dimensions are largely similar to human organs. We could use embryonic stem cells or induced stem cells to modify the immune-related genes in the pig to make the pig organ compatible to the human immune system. Then we could use these pigs as organ donors to provide organs for patients that won't trigger an adverse reaction from the patient's own immune system.
In addition to medical applications for pigs and humans, Dr Xiao said his discovery could be used to improve animal farming, not only by making the pigs healthier, but also by modifying the growth-related genes to change and improve the way the pigs grow. source
My comment: Absolutely awesome! And I think that they really have to take this study further-to see if those stem cells are really normal and harmless for the pigs. Because there is no much use of them, if they later turn out to be tumorous-something that wouldn't surprise me since they used a virus to change the cells. But if they are just like normal stem cells, that's absolutely fascinating and it really do open the door for lots of dreaming. And I don't mean transgenetic animals (WTF-who need a transgenetic animal or a plant, except for idiotic biotech corporations!). I mean new organs, new bodies, new life. We really are on the verge of something big and glorious and I hope we all manage to survive to see what that thing is.
Stem cells cultured on contact lens 'restore sight'
MELBOURNE: In what is claimed to a world- first breakthrough, scientists claim to have used stem cells cultured on contact lens to restore sight in the sufferers of blinding corneal disease.
A team at the University of New South Wales harvested stem cells from patients' own eyes to rehabilitate the damaged cornea. The stem cells were cultured on a common therapeutic contact lens which was then placed onto the damaged cornea for 10 days, during which the cells were able to re-colonise the damaged eye surface.
While the novel procedure was used to rehabilitate damaged corneas, the researchers say it offers hope to people with a range of blinding eye conditions and could have applications in other organs, the 'Transplantation' journal reported in its latest edition.
In fact, the trial was conducted on three patients -- two with extensive corneal damage resulting from multiple surgeries to remove ocular melanomas, and one with the genetic eye condition aniridia. Other causes of cornea damage can include chemical or thermal burns, bacterial infection and chemotherapy. source
My comment: Wow! That article, even if quite short, is amazing. Notice, this thing was done to HUMANS! And obviously, it worked! Too bad it doesn't say whether the manipulation was repeated by another team, but nevertheless, it's great. I mean this is something that can drastically improve the life of people. And if proven safe and working well, it could remove the corrective eye-glasses forever-you just grow yourself another cornea and you're fine. Or something like this-I might be wrong about the assumptions, but still, if true, this is big!
Bone-repairing stem cell jab hope
By Michelle Roberts
A team at Keele University is testing injectible stem cells that they say they can control with a magnet.
Once injected these immature cells can be guided to precisely where their help is needed and encouraged to grow new cartilage and bone, work on mice shows.
The aim is to treat patients with injuries and arthritis the UK National Stem Cell Network conference heard.
Professor Alicia El Haj, working with Professor John Dobson, also of Keele University, says the technology, patented by Magnecell, could be tested in humans within five years.
It would provide a way to treat disease without invasive surgery or powerful drugs.
The injection would use the patient's own stem cells, harvested from their bone marrow. These mesenchymal cells would be treated in the lab to give them a coating of minute magnetic particles. These same magnetic nanoparticles are already approved in the US where they are routinely used as an agent to make MRI scans clearer to read. Targeted magnetic fields could then move the cells around the body to the desired place and switch them into action without the need for drugs or other biochemical triggers.
Professor Jon Tobias of the Bone Research Society said: "Stem cells capable of regenerating diseased bones and joints can now been isolated and grown up outside the body, but the difficulty is in getting them to exactly the right place.source
Egg stem cells could revolutionise fertility treatment
- 18:00 12 April 2009 by Linda Geddes
The dogma that women are born with a finite number of eggs may soon be overturned. Stem cells have been discovered in the ovaries of adult mice that seem to give rise to new eggs and healthy offspring.
If these findings are confirmed, it could revolutionise female reproduction – opening the door for women to put off child-rearing almost indefinitely, and providing a new source of eggs for women who have been rendered infertile.
To isolate the mouse ovarian stem cells – dubbed female germline stem cells (FGSCs) – Ji Wu and his colleagues at Shanghai Jiao Tong University in China first looked for cells producing an egg-related protein called MVH in the ovaries of adult and five-day-old female mice. They then identified rapidly dividing cells and grew them in culture, where they continued to proliferate.
These FGSCs were injected into the ovaries of mice that had previously been sterilised by chemotherapy. Soon after, new eggs formed in the ovaries and the mice subsequently became pregnant and gave birth to healthy offspring. To confirm that the offspring really did come from the implanted eggs, Wu had inserted a gene encoding a fluorescent protein into the stem cells, which some of the offspring were also found to be carrying.
The next step will be for independent labs to replicate Wu's results – crucial, if they are to be accepted by the wider scientific community.
If Wu has indeed identified FGSCs, the burning question is whether adult women also carry similar cells in their ovaries – and what the role of these cells might be in adults. Wu's study doesn't suggest that FGSCs produce new eggs in healthy adult ovaries, and the fact remains that female mice – and humans – experience a decline in eggs as they age.
Even if these cells have no role in adults, if they exist in humans and can be extracted, it would open the doors to growing large numbers of eggs in a dish to repopulate damaged or depleted ovaries, and create embryos for childless couples, or embryonic stem cell research. source
Immune system taught to fight deadly skin cancer
Saturday, May 30, 2009
For the first time, a novel treatment that trains the immune system to fight cancer has shown modest benefit in late-stage testing against the deadly skin cancer melanoma.
The approach is called a cancer vaccine, even though it treats disease rather than prevents it. In a study of about 180 patients already getting standard therapy, the vaccine doubled the number of patients whose tumors shrank, and extended the time until their cancer worsened by about six weeks.
Trends in the study suggest that the vaccine also may improve survival, but patients need to be followed longer to see if this proves true, said Dr. Douglas Schwartzentruber, cancer chief at Goshen Health System in central Indiana.
The National Cancer Institute developed the vaccine, which has not yet been commercially licensed. The institute sponsored the study, along with Novartis AG, which makes interleukin-2, the standard treatment.
Interleukin-2 stimulates the immune system to make specialized cells that attack cancer. However, only 10 to 15 percent of patients with advanced melanoma see their tumors shrink with this harsh treatment, which causes severe flu-like symptoms and must be given in the hospital.
The vaccine contains a substance found on the surface of many skin cancer cells. The idea is to help the immune system recognize this as a threat and provoke it to attack.
In the study, people were given the vaccine or a dummy shot a day before starting intravenous interleukin-2 treatment. This was repeated about four to six times every three weeks.
About 22 percent of patients given the vaccine plus interleukin-2 saw their tumors shrink by half or more, compared with 10 percent of those getting interleukin-2 alone. Vaccine users saw their cancer stabilize for three months versus half that time for the others.
One safety issue: 15 patients receiving the vaccine developed a heart rhythm problem that was successfully treated with medicines, Schwartzentruber said.
Researchers will tweak the vaccine more to try to improve the number of people who benefit, said Dr. Patrick Hwu, melanoma chief at the University of Texas M.D. Anderson Cancer Center in Houston. It now can only be given to people with a certain tissue type — about half of those with melanoma.
The results also need to be confirmed in a longer, bigger study, Lichtenfeld said. source
Synthetic Fibers to Reverse BlindnessEric Bland, Discovery News
June 1, 2009 -- Synthetic fibers can now be embedded with three, and possibly more, drugs or proteins. The new fibers could be woven into a variety of materials that have unique and novel properties -- such as reversing blindness.
"The ultimate idea is to implant this material into the eye," said Bin Dong, a scientist from Drexel University who, along with Gary Wnek and Meghan Smith of Case Western University, detailed their work in the journal Small.
"One protein will eat the scar tissue away, and the other will help induce the differentiation of retinal progenitor cells," said Dong.
Previously scientists were only able to include one drug or protein inside an electrospun fiber because the two would often interact with each other in ways that would negate or modify their effects.
To get around this limitation, the Drexel and Case Western scientists put the drugs and proteins inside tiny capsules, which stop the molecules from interacting with each other until they break apart.
For their first tests, the scientists incorporated both bovine albumin serum (BAS) and epidermal growth factor (EGF) into the same electrospun fiber. Each molecule was also linked to a particular fluorescent dye that appears under special light. Red for BAS, green for EGF.
A fleece or nylon that glows different colors at different times is the beginning, though. Restoring vision to the blind could be the first use for these drug- and protein-containing fabrics.
Surgically implanted onto the retina during a 45-minute operation, the protein-equipped fabric would do two things. First, proteins in the fabric would eat away at the scar tissue created by diseases like retinitis pigmentosa and macular degeneration.
Once that's done, other capsules would break apart and release a growth factor that would encourage cultured retinal progenitor cells on top of the fabric to create new, light-detecting cells. The nanofiber material would then provide a place for these new cells attach to and grow on. Once the cells were established -- between 24 and 48 hours -- the material would naturally degrade.
"We've been able to show that in mice we can restore some kind of meaningful vision," said Young. "Pigs have compatible cells, and the next step is to restore vision for them as well."
If the animal trials go well, Young estimates that it will be a minimum of three years before any human trials of the material can be attempted.source