Posts tagged medicine
Articles and news from the latest research reports.
Stem cell materials could boost research into key diseases
Stem cell manufacturing for drug screening and treatments for diseases such as Huntington’s and Parkinson’s could be boosted by a new method of generating stem cells, a study suggests.
Scientists have developed a family of compounds that can support the growth of human embryonic stem cells on a large scale for use in drug testing or treatments.
The new materials, which are water-based gels, act as a tiny scaffold to which cells can cling as they grow. Normally cells must be grown on expensive biological surfaces that can carry pathogens and contaminate cells.
Once cells have multiplied sufficiently for their intended purpose, the gels can be cooled, enabling the stem cells to drop off the scaffold without becoming damaged.
The new approach surpasses existing techniques of separating cells by mechanical or chemical means, which carry a greater risk of damage to cells.
Scientists say the materials could offer a means of enabling the stem cells to be produced in large numbers efficiently and without the risk of inadvertent contamination, facilitating research, drug screening programmes and clinical applications that call for large numbers of cells.
Researchers at the University of Edinburgh developed the new materials by screening hundreds of potential compounds for their ability to support stem cell growth. From a shortlist of four, one has been found to be effective, and researchers say the remaining three show similar potential.
Stem cells provide a powerful tool for screening drugs as they can be used to show the effects of drugs on cells and systems within the body.
The study, published in Nature Communications, was supported by the European Union Framework 7 Grant Funding. The gels are being developed under licence by technology company Ilika.
Dr Paul de Sousa, of the University of Edinburgh’s Scottish Centre for Regenerative Medicine, said: “This development could greatly enhance automated production of embryonic stem cells, which would improve the efficiency and reduce the cost of stem cell manufacturing. We are also looking into whether this work could help develop pluripotent stem cells induced from adult cells.”
The Living Lab: Navigating into cells
How do viruses attach to cells? How do proteins interact and mediate infection? How do molecular machines organize themselves in healthy cells? How do they differ in diseased cells? These are the types of questions National Institutes of Health researchers ask in the recently established Living Lab for Structural Biology, questions they strive to answer through the most sophisticated of imaging techniques.
The Living Lab is an innovative partnership between NIH and FEI, an Oregon-based instrumentation company that manufactures advanced microscopes. FEI brings to the table invaluable assistance in developing and customizing electron microscopes for biological applications. Using that cutting edge technology, scientists in the Living Lab, unencumbered by any pressure to patent or otherwise protect discoveries for commercial purposes, can proceed purely driven by scientific and biomedical puzzles. Success of the Living Lab, which is on the NIH campus in Bethesda, Md., will rest on that collaboration between the government and the private sector—and the idea that answering scientific questions and technical advancement go hand in hand.
“We want to navigate our way into cells and into viruses,” said Sriram Subramaniam, Ph. D., director of the NIH component of the Living Lab. “We would like to be able to describe the function of complex things, such as whole cells or infectious viruses, in terms of their molecular make-up, and try to figure out how they work.”
The Living Lab’s advanced imaging technology allows researchers to tackle previously unanswered questions in structural biology by creating three-dimensional shapes of various molecular machines. Visualizing tiny details is a step toward understanding the molecular origins of disease. “The prospects for studying structures of a broad spectrum of medically relevant complexes at minute resolutions has changed dramatically in recent years with advances in structural biology,” said Subramaniam. “Our goal with the Living Lab is to capture the synergy between all of these methods including the latest advances in cryo-electron microscopy to extend these advances to key scientific challenges in modern structural biology.”
Subramaniam, who earned his doctorate at Stanford University and did post-doctoral work at the Massachusetts Institute of Technology in chemistry and biology, directs the research activities of the Living Lab, in close consultation with other team members from FEI and from the National Institute of Diabetes and Digestive and Kidney Diseases.
Rainfall, brain infection linked in sub-Saharan Africa
The amount of rainfall affects the number of infant infections leading to hydrocephalus in Uganda, according to a team of researchers who are the first to demonstrate that these brain infections are linked to climate.
Hydrocephalus — literally “water on the brain” — is characterized by the buildup of the fluid that is normally within and surrounding the brain, leading to brain swelling. The swelling will cause brain damage or death if not treated. Even if treated, there is only a one-third chance of a child maintaining a normal life after post-infectious hydrocephalus develops, and that chance is dependent on whether the child has received the best treatment possible.
"The most common need for a child to require neurosurgery around the world is hydrocephalus," said Steven J. Schiff, the Brush Chair Professor of Engineering, director of the Penn State Center for Neural Engineering and a team member.
In sub-Saharan Africa, upward of 100,000 cases of post-infectious hydrocephalus a year are estimated to occur. The majority of these cases occur after a newborn has suffered from neonatal sepsis, a blood infection that occurs within the first four weeks of life, the researchers reported in a recent issue of the Journal of Neurosurgery: Pediatrics.
Benjamin C. Warf, associate professor of neurosurgery, Harvard Medical School, Boston Children’s Hospital, noticed that about three or four months after an infant in East Africa had an infection like neonatal sepsis, the child would often return to the clinic with a rapidly growing head — hydrocephalus. Schiff joined Warf to help figure out what caused this disease so frequently.
Schiff and colleagues tracked 696 hydrocephalus cases in Ugandan infants between the years 2000 and 2005. The researchers obtained localized rainfall data for the same time frame through NOAA (National Oceanic and Atmospheric Administration) weather satellites using the African Rainfall Estimation Algorithm developed at the U.S. NOAA Climate Prediction Center.
Uganda has two peak rainfall seasons, in spring and fall. By comparing the data from NOAA and the hydrocephalus cases, the researchers found that instances of the disorder rose significantly at four different times throughout the year — before and after the peak of each rainy season, when the amount of rainfall was at intermediate levels. In Uganda an intermediate rainfall is about 6 inches of rain per month.
Schiff and colleagues previously noted that different bacteria appear associated with post-infectious hydrocephalus at different seasons of the year. While the researchers have not yet characterized the full spectrum of bacteria causing hydrocephalus in so many infants, they note that environmental conditions affect conditions supporting bacterial growth, and that the amount of rain can quench bacterial infections. The moisture level clearly affects the number of cases of hydrocephalus in this region of East Africa.
"Hydrocephalus is the first major neurosurgical condition linked to climate," said Schiff, who is also professor of neurosurgery, engineering science and mechanics, and physics, and a faculty member of the Huck Institutes of the Life Sciences. "This means that a substantial component of these cases are almost certainly driven from the environmental conditions, and that means they are potentially preventable if we understand the routes and mechanisms of infection better."
It’s All About the Genes and the Brain Machines
(Image: U.S. Dept. of Energy Office of Science)
The amount of time and money needed to sequence genomes continued to fall this year, perhaps to no one’s surprise. But while the field seemed to be finally approaching the heralded $1,000 human genome, the implications of reaching that milestone are not clear. Without expert analysis, the result of sequencing a human genome is just a large file of letters. You still need to manipulate and understand what those letters mean. Different companies announced services to help, from initial processing and storage of data to interpretation of the genetic data into medical meaning.
As human genomics garnered more attention from the medical community, the technology attracted new business opportunities. In April, the company behind the most widely used DNA sequencer, Illumina, fought off a hostile bid from pharmaceutical giant Roche. Just seven months later, Illumina tried to take over Complete Genomics, a company with technology well suited to medical genomics but which has never achieved financial success. That offer followed what seemed to be an all-but-assured purchased of Complete Genomics by China’s BGI. Illumina and BGI continue to fight over Complete Genomics.
Still, the medical community is only at the cusp of its understanding of how genome sequences can be used to help patients. Two branches of medicine that seem to be at the forefront of bringing on board DNA technology are reproductive medicine and cancer. Early in the summer, scientists at the University of Washington in Seattle reported a technique for determining the genome sequence of a fetus by analyzing DNA in the mother’s blood and from the father. Illumina’s CEO Jay Flatley said that prenatal diagnostics will be a major focus for the company, which has been expanding its business from sequencer manufacturing to broad DNA analysis service. In September, Illumina purchased BlueGnome, a chromosome-focused diagnostic company whose technology can detect abnormal numbers of chromosomes in IVF embryos. DNA analysis could also help prior to conception, according to a start-up called GenePeeks. That company announced it would offer predictive genome analysis for sperm bank clients to help guide them away from risky donor matches.
Cancer patients and their doctors were also early adopters of medical genome science this year. Cancer is a disease of the genome: genetic mutations lead to abnormal cellular proliferation and behavior. Each person’s tumor and even different cells within a single tumor can have a unique profile of mutations, which makes finding the right drug to treat each patient difficult. Cambridge, Massachusetts-based Foundation Medicine offered a sequencing service that searches for mutations that can be addressed with drugs in a patient’s tumor. Another Cambridge company, H3 Biomedicine, is using public databases of tumor sequences to find new drug targets specific to certain patient populations.
Genetic medicines also got a boost with the first Western approval of gene therapy in November. Amsterdam-based Uniqure will begin selling its virus-mediated gene correction for a rare metabolic disorder sometime next year. The announcement could be good news for other companies trying to develop gene therapies as well as other groups developing molecular medicines, such as gene-silencing RNAi treatments that continue to move through clinical trials.
Although still untested in patients, another genetic manipulation is proving to be a powerful tool for neuroscientists. With optogenetics, scientists can manipulate neuron activity with flashes of light, and this year a group demonstrated for the first time that primate behavior could be controlled with the technique. Lab animal studies this year suggest optogenetics might one day help patients with blindness caused by retinal degeneration.
The melding of mind and machine was also big this year. Scientists in Winston-Salem, North Carolina, demonstrated that a brain implant could replace some cognitive function in primates, which could one day help people with brain damage. On the flip side, two research groups published the first accounts of quadriplegic people using brain implants to control robotic limbs. The implants recorded the participants’ intentions to move, which were translated by a computer into instructions for a robotic arm. The idea is that one day people with severe paralysis or amputations could use such neural prosthetics at home to help with the tasks of daily life.
Brain electronics were also implanted into Alzheimer’s patients this year in an attempt to slow a disease that has so far evaded pharmaceutical treatment. The urgency for treatment is growing, but the community still doesn’t know what sets into motion the cascade of molecular events that robs people of their memory and thinking skills. With better diagnostic tools and the discovery that there are warnings decades before symptoms, scientists are turning to treating patients with a genetic predisposition for the disease before they start having symptoms. Perhaps this will be the key to treatments in future years.
(Source: technologyreview.com)
'Lady of the Cells' Dead at 103
Italy has lost a truly fascinating centenarian. Nobel Prize winner Rita Levi-Montalcini died at her home yesterday at age 103, leading Rome’s mayor to declare the scientist’s death a loss “for all of humanity.” It may not be much of an exaggeration: The so-called “Lady of the Cells” faced many obstacles, reports the AP: a father who believed women should not study (she ultimately obtained a degree in medicine and surgery), a Fascist regime (Levi-Montalcini lost her neurobiology job in 1938 when Jews were banned from major professions), and the Nazis, whose 1943 invasion of Italy forced her family to flee to Florence and live underground.
But the petite woman’s determination was formidable: In the face of the Fascist regime she studied chicken embryos in a makeshift lab in her bedroom. She chose not to marry or have a family—without hesitation or regret, she once said—fearing doing so would weaken her independence. She claimed to sleep no more than three hours a night, and worked well into her final years. That effort produced contributions that were just as formidable.
Levi-Montalcini shared the Nobel medicine prize in 1986 with American biochemist Stanley Cohen for their groundbreaking cellular research. Her research increased the understanding of many conditions, including tumors, developmental malformations, and senile dementia.
(Image: AP Photo/Riccardo De Luca)
Stem Cells Could Extend Human Life by Over 100 Years
When fast-aging elderly mice with a usual lifespan of 21 days were injected with stem cells from younger mice at the Institute for Regenerative Medicine in Pittsburgh, the results were staggering. Given the injection approximately four days before they were expected to die, not only did the elderly mice live — they lived threefold their normal lifespan, sticking around for 71 days. In human terms, that would be the equivalent of an 80-year-old living to be 200.
Chimera Monkeys Created from Multiple Embryos
While all the donor cells were from rhesus monkeys, the researchers combined up to six distinct embryos into three baby monkeys. According to Dr. Mitalipov, “The cells never fuse, but they stay together and work together to form tissues and organs.” Chimera species are used in order to understand the role specific genes play in embryonic development and may lead to a better understanding of genetic mutation in humans.
New Research Shows Music Improves Health and Disease
Music has been incorporated into medical practice since before the ancient Greeks. However, though practitioners have been convinced of music’s health benefits for thousands of years, there had been little peer-reviewed research to back them up. But recent studies are providing an empirical backbone for the anecdotal evidence. A 2012 scientific review, published in the journal Nutrition, collects information from a number of studies to support music’s influence on the hypothalamic-pituitary-adrenal (HPA) axis, the sympathetic nervous system (SNS) and the immune system. These results support the experiences of complementary practitioners, who have long used music to help heal.
“As an integrative physician and traditional Chinese medicine practitioner, the healing power of music has always been an important part of my practice and family life,” says integrative medicine pioneer Isaac Eliaz, M.D. “Harmony and tempo help synchronize the rhythms of the natural world with the music of the heart – each person’s individual energetic pattern, expressed in their pulse.”
Proven Medicine
The review highlighted a number of studies that confirm music’s healing potential. For example, music reduces levels of serum cortisol in the blood. An important player in the HPA axis, cortisol increases metabolic activity, suppresses the immune system and has been associated with both anxiety and depression. A number of studies have shown that exposing post-operative patients to music dramatically lowers their cortisol levels, enhancing their ability to heal.
Other studies in the review measured music’s impact on congestive heart failure, premature infants, immunity, digestive function and pain perception. In particular, music’s effects on the limbic and hypothalamic systems reduced the incidence of heart failure. Other studies showed that surgical patients required less sedation and post-operative pain medication.
“These results only confirm what I have observed for many years in my practice,” says Dr. Eliaz. “Music produces quantifiable healing. For example, my daughter Amity, a professional musician, regularly plays her songs for chronically ill patients who express how uplifting her music is. These performances do more than encourage good feelings, they help the body heal on a molecular level.”
Powerful Impact
Perhaps the most interesting aspect of music’s healing properties is how widespread they are. For example, music also aided recovery time following strenuous exercise. Other studies showed that fast-paced music can increase resting metabolism, which may prove helpful for people trying to lose weight.
“Modern science has just begun to scratch the surface of music and sound in terms of healing potential,” says Dr. Eliaz. “However, traditional medical systems from around the world have long revered the beneficial vibrations of music, harmony and rhythm for health and vitality. The effects are instant and tangible, but they are also powerful and long lasting.”
Ontario man’s sight restored with help of stem cells
When Taylor Binns slowly began going blind because of complications with his contact lenses, he started to prepare for living the rest of his life without vision. But an innovative treatment using stem cells has changed all that, and returned to him the gift of sight.
Four years ago, while on a humanitarian work mission to Haiti, Binns developed intense eye pain and increasingly blurry vision. Doctors at home couldn’t figure out what was wrong and, over the next two years, Binns slowly went legally blind, no longer able to drive or read from his textbooks at Queens University, where he was studying commerce.
“Everything you could do before was being taken away, day by day, and it got worse and worse,” he recalls.
Doctors finally diagnosed him with a rare eye disease called corneal limbal stem cell deficiency, which was causing the normal cells on Binns’ corneas to be replaced with scar tissue, leading to painful eye ulcers that clouded over his corneas.
A variety of things can cause the condition, including chemical and thermal burns to the corneas, which are the glass “domes” over the coloured part of our eyes. But it’s also thought that microbial infections and wearing daily wear contact lenses for too long without properly disinfecting them can lead to the disease, too.
Since a corneal transplant was not an option for Binns, his doctors at Toronto Western Hospital proposed something new: a limbal stem cell transplant.
The limbus is the border area between the cornea and the whites of the eye where the eye normally creates new epithelial cells. Since Binns’ limbus was damaged, doctors hoped that giving him healthy limbal cells from a donor would cause healthy new cells to grow over the surface.
While the treatment is available in certain centres around the U.S., Binns became the first patient to try the treatment at a new program at Toronto Western Hospital.
“Within a month he could see 20/40,” says ophthalmologist Dr. Allan Slomovic. “His last visit he was 20/20 and 20/40.” Slomovic says “it’s extremely exciting” that the procedure was a success, “especially when you realize there is really nothing else that would have worked for him.”
Binns is now living pain-free, returning to doing everything he used to before his three-year sight loss. “Being able to see my computer, being able to go for a walk or a drive — I am so happy for that,” he says.
The Toronto team hopes to do many more of these procedures in the future, says Dr. Sherif El Defrawy from the Canadian Ophthalmological Society and University of Toronto’s ophthalmology department.
“We are already seeing this in a number of centres across the country and you will see it more and more as we understand how to improve the success rate,” he says.
For Binns, the experience has been life-changing in one more important way: He has now decided to switch his studies from commerce to medicine, and hopes to go to school to become an ophthalmologist.
Research offers new targets for stroke treatments
New research from the University of Georgia identifies the mechanisms responsible for regenerating blood vessels in the brain.
Looking for ways to improve outcomes for stroke patients, researchers led by the UGA College of Pharmacy assistant dean for clinical programs Susan Fagan used candesartan, a commonly prescribed medication for lowering blood pressure, to identify specific growth factors in the brain responsible for recovery after a stroke.
The results were published online Dec. 4 in the Journal of Pharmacology and Experimental Therapeutics
Although candesartan has been shown to protect the brain after a stroke, its use is generally avoided because lowering a person’s blood pressure quickly after a stroke can cause problems-like decreasing much-needed oxygen to the brain-during the critical period of time following a stroke.
"The really unique thing we found is that candesartan can increase the secretion of brain derived neurotrophic factor, and the effect is separate from the blood pressure lowering effect," said study coauthor Ahmed Alhusban, who is a doctoral candidate in the College of Pharmacy. "This will support a new area for treatments of stroke and other brain injury."
Alhusban and Fagan worked with Anna Kozak, a research scientist in the college, and Adviye Ergul, a professor and director of the physiology graduate program at Georgia Health Sciences University. They are the first to show that the positive effects of candesartan on brain blood vessel growth are caused by brain derived neurotrophic factor, or BDNF.
The research shows that when candesartan blocks the angiotensin II type 1 receptor, which lowers blood pressure, it stimulates the AT2 receptor and increases the secretion of BDNF, which encourages brain repair through the growth of new blood vessels.
"BDNF is a key player in learning and memory," said Fagan, the Albert W. Jowdy Professor. "A reduction of BDNF in the brain has been associated with Alzheimer’s disease and depression, so increasing this growth factor with a common medication is exciting."
AT2 is a brain receptor responsible for angiogenesis, or the growth of new blood vessels from pre-existing vessels. Angiogenesis is a normal and vital process in human growth and development-as well as in healing.
(Image: iStock)
Hybrid tunnel may help guide severed nerves back to health
Building a tunnel made up of both hard and soft materials to guide the reconnection of severed nerve endings may be the first step toward helping patients who have suffered extensive nerve trauma regain feeling and movement, according to a team of biomedical engineers.
"Nerve injury in both central nervous system and peripheral nervous system is a major health problem," said Mohammad Reza Abidian, assistant professor of biomedical engineering, Penn State. "According to the National Spinal Cord Injury Statistical Center, there are approximately 290,000 individuals in the US who suffer from spinal cord injuries with about 12,000 new injuries occurring each year."
Spontaneous nerve regeneration is limited to small lesions within the injured peripheral nerve system and is actively suppressed within central nervous system. When a nerve in the peripheral nervous system is cut slightly, nerve endings can regenerate and reconnect. However, if the distance between the two endings is too far, the growth can go off course and fail to connect.
The researchers, who published their results in the current issue of Advanced Healthcare Materials, developed a novel hybrid conduit that consisted of a soft material, called a hydrogel, as an external wall along with an internal wall made of an electrically-active conducting polymer to serve as a tunnel that guides the regrowth and reconnection of the severed nerve endings.
Abidian said that the method could offer advantages over current surgeries that are used to reconnect severed nerves.
"Autografts are currently the gold standard for bridging nerve gaps," said Abidian. "This is an operation that takes the nerve from another portion of the body — for instance — from a tendon, and then it is grafted onto the injured nerve."
However, the operation can be painful and there are often mismatches in size between the severed nerve endings and the new grafted portion of the nerve, Abidian said.