Saturday, July 27, 2013

NICE gives green light to treatment for wet AMD in final guidance

The National Institute for Health and Care Excellence (NICE) has published final guidance recommending aflibercept solution for injection as an option for treating wet age-related macular degeneration (AMD).
Wet AMD is an eye condition that affects the macula (a tiny part of the retina at the back of the eye). AMD causes problems with central vision - for example, straight lines may appear wavy and blind spots may develop in the field of vision.
Macular degeneration is diagnosed as either dry (non-neovascular) or wet (neovascular). Neovascular refers to growth of new blood vessels in an area, such as the macula, where they are not supposed to be.
There are an estimated 26,000 new cases of wet AMD in the UK each year. Risk factors include increasing age, cigarette smoking (smokers having a 3.6 times greater risk of developing age-related macular degeneration compared with people who have never smoked), and exposure to high levels of UV light. It is also more common in women than men [i].
Aflibercept is recommended as an option for treating wet age related macular degeneration only if: it is used in accordance with the recommendations for ranibizumab in NICE technology appraisal guidance 155 [ii] (re-issued in May 2012), and the manufacturer provides aflibercept solution for injection to the NHS under the terms agreed with the Department of Health as part of a patient access scheme.
Professor Carole Longson, Health Technology Evaluation Centre Director at NICE said: "Wet AMD can have a significant impact on vision, independence and quality of life. Today's guidance, which comes soon after aflibercept received its licence, provides healthcare professionals with clear advice on where and when this treatment can add value as another treatment option for those affected by this distressing condition. "
This is NICE's final guidance on this technology and now replaces local recommendations across the country.

About the guidance

  • The guidance is available on the NICE website.
  • People currently receiving aflibercept solution for injection whose disease does not meet the criteria detailed above should be able to continue treatment until they and their clinician consider it appropriate to stop.
  • Aflibercept solution for injection (Eylea, Bayer Pharma) is a soluble vascular endothelial growth factor (VEGF) receptor fusion protein which binds to all forms of VEGF-A, VEGF-B, and the placental growth factor. Aflibercept solution for injection prevents these factors from stimulating the growth of the fragile and permeable new blood vessels associated with wet age-related macular degeneration. Aflibercept solution for injection has a UK marketing authorisation 'for adults for the treatment of neovascular (wet) age-related macular degeneration (AMD)'.
  • The summary of product characteristics states that the recommended dose for aflibercept is 2 mg and that treatment should be given monthly for 3 consecutive 2 mg doses, followed by 1 injection every 2 months. Each 100 microlitre vial contains 4 mg of aflibercept. Aflibercept solution for injection must only be administered by a qualified doctor experienced in administering intravitreal injections. The summary of product characteristics also states that there is no need for monitoring between injections. After the first 12 months of treatment, the treatment interval may be extended based on visual and anatomic outcomes. In this case, the schedule for monitoring should be determined by the treating doctor.
  • The list price of aflibercept 40 mg/ml solution for injection is £816 per 100-microlitre vial (excluding VAT; 'British national formulary' [BNF] edition 52).
  • The Committee noted that its preferred analyses incorporated the confidential discount to the list price of aflibercept and a range of discounts (from 0 to 50%) to the list price of ranibizumab. It also noted that, when discounts to the list price of ranibizumab ranged from 0 to 45%, aflibercept had lower costs and quality-adjusted life years (QALYs) than ranibizumab, which resulted in ICERs for aflibercept compared with ranibizumab ranging from £1,692,500 to £16,700 saved per QALY lost and that, when a 50% discount was applied to the list price of ranibizumab, aflibercept was dominated by ranibizumab in both the worse-seeing eye and better-seeing eye model. However, the Committee was aware that, in both the manufacturer's and the ERG's analyses, the differences in total costs and QALYs were very small. The Committee therefore concluded that aflibercept could be recommended as a cost effective use of NHS resources if ranibizumab would otherwise be the treatment used.
  • The independent Appraisal Committee decided that an appraisal consultation document (ACD) was not needed for this appraisal, so the recommendations went straight to a final appraisal determination (FAD). This happens when the Committee recommends a treatment in line with its licensed indication.
  • The manufacturer of aflibercept has agreed a patient access scheme with the Department of Health. This involves a confidential discount applied to the list price of aflibercept solution for injection. The level of the discount is commercial-in-confidence.
  • NICE technology appraisals apply across the NHS in England and Wales.
  • Section 7(6) of the National Institute for Health and Care Excellence (Constitution and Functions) and the Health and Social Care Information Centre (Functions) Regulations 2013 requires clinical commissioning groups, NHS England and, with respect to their public health functions, local authorities to comply with the recommendations in this appraisal within 3 months of its date of publication.
  • Further details on NICE technology appraisals.

Statement from RNIB

Steve Winyard, RNIB's Head of Campaigns, said: "We welcome the news NICE has approved the use of a further drug to treat the biggest cause of sight loss in the UK.
"Not only does it mean patients now have the choice of two different drugs to treat their condition, it also means if they choose the newly approved drug it could mean less visits to the hospital.
"Some people with wet AMD do not respond to the current NICE approved treatment and another option could mean the difference between saving and losing their sight.
"We've recently launched a national campaign encouraging over 50s to spot the signs of wet AMD, which affects about 40,000 people each year and can destroy a person's sight in as little as three months.
"Losing your central vision can have profound consequences with many people unable to carry out basic tasks such as driving, chopping vegetables, or writing a shopping list. However, it doesn't have to be this way and people should not be losing their sight unnecessarily when there's treatment available."
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New links between diet and acne

A review carried out by the University of Hull has shed new light on the relationship between acne and diet.
Published in Dermatological Nursing, the comprehensive review assesses the latest evidence and findings about the effects of food and nutrition on acne and suggest that high glycemic index foods such as milk could exacerbate the skin condition.
The review was carried out by HONEI (Humber Obesity Nutrition Education and Innovation) a centre for food research, based at the University of Hull.
Acne is one of the most common skin conditions and is often associated with adolescents but its prevalence among adults is increasing.
Facial acne can be stigmatising and deeply upsetting. Research has shown that the adverse social, psychological and emotional effects of acne can be comparable to those of more serious chronic conditions such as; epilepsy, diabetes arthritis or psoriasis.
Extensive studies have been carried out to assess the impact diet has on acne and research has so far suggested some diets, such as those containing high glycemic index foods e.g. milk can exacerbate acne.
HONEI is a world-leading centre of food related research and has previously conducted studies into the effect of dark chocolate on cholesterol levels as well as studies on soy to determine whether it could help combat certain health problems associated with osteoporosis and type 2 diabetes. HONEI is also currently undertaking extensive research into the benefits of polyphenols on cardiovascular health.
Dr Katerina Steventon, Research Fellow with HONEI and the University of Hull's Faculty of Health and Social Care, said: "There is growing evidence of the link between diet and acne which is becoming stronger as new evidence comes to light, although nothing has been fully proven yet, it is only a matter of time.
"The research review suggests a low glycemic index diet but also a healthy diet, rich in fruit and vegetables, can have a protective effect on acne. Further research is needed to fully understand the role diet plays in acne in specific populations."
HONEI will be carrying out its own primary research examining the effects of certain foods on acne later this year.
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Full moon affects not only werewolves but human sleep too

It appears there is some truth in the saying that it is harder to get a good night's sleep when the moon is full. Tests on Swiss volunteers as they spent nights in a sleep lab showed a link between moon phases and sleep patterns: sleep was more disturbed when there was a full moon.
Led by a team from the University of Basel, the researchers report in the July 25th online issue of Current Biology how they found a full moon disrupts sleep quality.
Lead author Professor Christian Cajochen, who is based at the Centre for Chronobiology at the Psychiatric Hospital of the University of Basel, and colleagues analyzed data taken from over 30 healthy volunteers of various ages as they slept in a sleep lab.
As the participants slept, their brain activity, eye movements, and hormone levels in different phases of sleep were measured.
Neither the lab researchers who took the sleep measurements nor the participants were aware that the authors were later going to do an analysis of the sleep data against moon cycles.
It was only after the lab results were produced that it was decided to compare them to moon phases.
Also, the participants could not see the moon from their beds in the sleep lab.
The analysis showed that the participants did not sleep so well when there was a full moon. This was reflected in both subjective measures (where the participants themselves said whether their night's sleep had been good or not) and the objective measures.
On nights with a full moon:
  • Brain activity associated with deep sleep (during non-rapid eye movement) fell by nearly a third,
  • On average it took the volunteers 5 minutes longer to fall asleep, and their sleep was 20 minutes shorter, and
  • There was a drop in levels of melatonin, a protein that helps regulate sleep and wake cycles.
The authors write:
"This is the first reliable evidence that a lunar rhythm can modulate sleep structure in humans when measured under the highly controlled conditions of a circadian laboratory study protocol without time cues."
Cajochen suggests the response to moon phase that they observed, which they call the "circalunar rhythm," could be a relic of ancient times when human behavior was more heavily influenced by the moon.
It would seem that even for some of today's humans, paying attention to phases of the moon can be a lifesaver. A study published in 2011 suggests you are less likely to end up as a lion's dinner if you pay close attention to the moon; in southeastern Tanzania, that is.
There is evidence that many organisms, especially those that live in the sea, are influenced by moonlight.
However, this study finds that even without being able to see the moonlight, the body is somehow still responding to the fact it is a full moon.
It remains for other studies now to uncover the biology that explains this influence.
A large study from the Netherlands published earlier this month suggests that a good night's sleep boosts the benefits of a healthy lifestyle on the heart.
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'Marijuana in adolescence can cause permanent brain damage'

New research may give backing to parents telling teens to "just say no." A study in mice from the University of Maryland School of Medicine reveals that regular use of marijuana during adolescence could damage brain function, potentially increasing the risk for schizophrenia and other psychiatric problems.
The study, which was recently published in Neuropsychopharmacology, had scientists examining cortical oscillations - patterns of the brain's neuron activity - in mice. These oscillations become abnormal when schizophrenia or other psychiatric disorders are present.
Researchers exposed young mice to low doses of tetrahydrocannabinol (THC), which is the active ingredient present in marijuana, for 20 days. Then the mice were returned to their family to continue developing.
When the mice became adults, the scientists discovered that their cortical oscillations were severely modified, and the mice showed signs of impaired cognitive functions.
Sylvina Mullins Raver from the University of Maryland says: "The striking finding is that, even though the mice were exposed to very low drug doses, and only for a brief period during adolescence, their brain abnormalities persisted into adulthood."

Effects of marijuana (or not) on adult brains

Interestingly, the researchers originally set out to test a hypothesis that marijuana use effects cortical oscillations in adults. But when they repeated the experiment on adult mice who had never been exposed to the drug previously, they found that both the oscillations and cognitive behavior stayed normal.
So, it appears that adolescence is the period of development when marijuana use can take its biggest toll. Senior author Dr. Asaf Keller adds:
"We looked at the different regions of the brain. The back of the brain develops first, and the frontal parts of the brain develop during adolescence.
We found that the frontal cortex is much more affected by the drugs during adolescence. This is the area of the brain that controls executive functions, such as planning and impulse control. It is also the area most affected in schizophrenia."

Implications for marijuana legalization

Now that marijuana has been legalized in 19 US states and the District of Columbia, the study's results about long-term effects of marijuana use are particularly relevant. The authors point to controversy spanning back to 20 years ago about whether or not marijuana use can cause permanent damage and contribute to psychiatric disorders.
Dr. Keller adds: "There is likely a genetic susceptibility, and then you add marijuana during adolescence and it becomes the trigger."
The research team will continue to study the changes in cortical oscillations with a view to potentially reverse the effects some day.
"We are hoping we will learn more about schizophrenia and other psychiatric disorders, which are complicated conditions,"
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Visit gym or take a pill? Drug mimics exercise

Science gets a lethargic cheer from lazy people around the world this week, as a study published in Nature magazine reveals that we may one day be able to take a compound that produces similar effects in the body as exercise.
The study comes from researchers at the Scripps Institute in Jupiter, FL, who injected overweight mice with a compound they created. As reported in the New York Times, the results show that the researchers' compound increased activation of Rev-erb, a protein involved in controlling circadian rhythms and biological clocks. As such, the mice lost weight and improved their cholesterol, even while continuing to eat a high-fat diet.
What's more, the mice used more oxygen during the day and 5% more energy than the control group. The interesting thing to note here is that the treated mice did not exercise any more than the untreated mice. In some cases, the Times report says, the treated mice were lazier and more inactive than they were before the injections.

How the compound works

People exercising in gym
Though researchers from Scripps Institute created a compound that mimics exercise, they still say many benefits of exercising cannot be recreated in a drug.
In muscles, regular exercise increases the amount and power of mitochondria, which are the powerhouses that generate most of the cell's energy.
When the researchers injected their compound into various muscle cells in the mice, those cells then released an increased amount of Rev-erb. As a result, those cells created new mitochondria and strengthened the existing ones.
Thomas Burris, co-author of the study, said that the drug "certainly seems to act as an exercise mimic," and reportedly said that the drug might be able to allow people who are disabled or incapacitated to attain benefits of exercise without actually physically doing it.

But is taking a pill for exercise really recommended?

The results of the study will prompt several discussions about the ethical, as well as the physical, implications of using a pill to achieve exercise results. For example, would it become a banned doping drug used by professional athletes?
Thomas Burris says that he has been warned by other scientists "to expect some weird phone calls." But he says his main goal is to help people who are unable to exercise rather than those who choose not to.
Burris also notes that there are many benefits to exercising that cannot all be recreated in a drug.
Recent studies have shown that exercise can have an effect at the DNA level against fat cells, as well as help the brain become more resilient.
In short, if you are able to exercise, you probably should.
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Common blood pressure drugs may slow dementia decline

A class of drug used to lower blood pressure could potentially slow the rate of cognitive decline in dementia and even boost brain power, according to a study published by BMJ Open.
Researchers from Ireland analyzed the cognitive decline and brain power of 361 patients with an average age of 77. All had been diagnosed with either Alzheimer's disease, vascular dementia, or a mixture of both.
Of these patients, 85 were already using the blood pressure-lowering (antihypertensive) drugs known as ACE inhibitors (angiotensin-converting enzyme inhibitors). This is a commonly used class of antihypertensive drug. Thirty of the patients who were newly prescribed ACE inhibitors during the first six months of treatment were also analyzed for their brain power activity.
Between the years 1999 and 2010, the researchers used the Standardized Mini Mental State Examination (SMMSE) or the Quick Mild Cognitive Impairment (Qmci) to test the cognitive decline of each patient. This was done on two separate occasions, six months apart.
The patients who were taking ACE inhibitors had slower rates of cognitive decline in the study compared with patients who were not taking the drugs.
The study also revealed that in patients who had been newly prescribed the ACE inhibitors over the six-month period, their brain power improved in comparison with both those already taking them and those not taking them at all.
However, the study authors add that this could be due to the newly prescribed patients having better control over their medication regimen, or due to better blood pressure control or improved blood flow to the brain.
The researchers say:
"This [study] supports the growing body of evidence for the use of ACE inhibitors and other [blood pressure-lowering] agents in the management of dementia.
Although the differences were small and of uncertain clinical significance, if sustained over years, the compounding effects may well have significant clinical benefits."
The researchers warn, however, that previous research has indicated that ACE inhibitors may be harmful in some cases, so if future benefit of the drugs in dementia is proven, it may be limited to certain groups of patient.
The study authors call for further research and a controlled trial to confirm their findings. They say:
"If these data can be reproduced in a randomized trial of sufficient length, incorporating appropriate outcome measures, such as an amyloid positron emission tomography (PET), then these agents are likely to have significant benefits in delaying or even preventing dementia."
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Virus discovery: 'blast' mechanism used to infect host

Researchers have discovered the first "pressure-driven infection mechanism" in a human virus, which blasts infectious DNA into cells with pressure eight times higher than that of a typical car tire.
The study, published in the Journal of the American Chemical Society, suggests that this discovery could open the door to new treatments for viral infections.
Researchers from the US and Sweden analyzed the pressure inside the herpes simplex virus 1 (HSV-1), the infection that causes cold sores.
It was found that the HSV-1 virus enters human cells, settles on the nucleus and then blasts its way into DNA using high pressure built up from a "nanometer-scale protein shell" called the capsid, researchers explain. The capsid is the shell that contains the viral genome.
The researchers say that the viruses responsible for infections such as influenza and HIV are quickly becoming resistant to drugs that target viral proteins. The proteins can quickly disguise themselves and become resistant to ant-viral drugs as a result of genetic mutation.
For example, previous research published in PLoS Computational Biology has suggested that drug resistance to HIV, the virus that causes AIDS, can be caused by pre-existing mutations, which can actually progress even more once treatment is initiated.
Findings such as this one have led to a search for weaknesses in viruses that do not involve viral proteins, the researchers add, a reason why this study was conducted.
Previous research has also shown many viruses that infect bacteria, called bacteriophages, use the same pressure-driven mechanism in order to blast their DNA into bacteria nuclei.
They add that the same mechanism also exists in eight related viruses, including chickenpox in children, shingles in adults, and the virus responsible for mononucleosis.
The researchers believe that evolution has meant that this technique is now apparent in viral infection, paving the way for the development of treatments that can defeat particular viruses, such as HSV-1, in the same way.
They say:
"Despite billions of years of evolution separating eukaryotic viruses and bacteriophages, pressure-driven DNA ejection has been conserved. This suggests it is a key mechanism for viral infection and thus presents a new target for antiviral therapies."
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"More harm than good" from red grape antioxidant

A natural antioxidant found in red grapes, resveratrol, may not be as beneficial as previously thought. New research in older men suggests that it may counteract the benefits of cardiovascular exercise.
The study comes from researchers at the University of Copenhagen, who suggest that eating an antioxidant-rich diet may hinder the health benefits of exercise, such as lower blood pressure and cholesterol.
The researchers note that since aging is associated with impaired vascular functions due to oxidative strain, resveratrol - which has been shown to decrease vascular disease and improve cardiovascular health - was initially expected to improve cardiovascular health in older men. After all, it has been proven in animal studies to be of benefit in that department.
But in a surprise twist, the researchers found that unlike in our animal counterparts, resveratrol actually impairs the cardiovascular benefits of exercise in older men.
For 8 weeks, the researchers followed 27 men who were around 65 years of age and in good health. During that time, the men all took part in high-intensity exercise, but half of the men received 250 mg of resveratrol each day, while the other half received a placebo pill.
Lasse Gliemann, a researcher who worked on the study, explains the results and design of the experiment:
"The study design was double-blinded, thus neither the subjects nor the investigators knew which participant received either resveratrol or placebo."
"We found that exercise training was highly effective in improving cardiovascular health parameters, but resveratrol supplementation attenuated the positive effects of training on several parameters, including blood pressure, plasma lipid concentrations and maximal oxygen uptake."
So even though the men were gaining health benefits from exercising, the ones who took a daily dose of resveratrol saw many of these benefits effectively wiped out.
There have been several studies lately both lauding and denouncing the health benefits of resveratrol. A 2012 study, for example, shows resveratrol's potential as a therapy for diabetes, Alzheimer's disease and heart disease. Yet, another study from the same year reveals that the antioxidant may not benefit healthy women.
Though there are arguments for and against the compound found in red wine, this particular study from the University of Copenhagen suggests that "reactive oxygen species, generally thought of as causing aging and disease, may be a necessary signal that causes healthy adaptions in response to stresses like exercise."
In short, ingesting too many antioxidants may not be a good thing, but the researchers do say that the amount of resveratrol given to the men in the study exceeds what would normally be ingested through food alone.
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Hope that nerve damage in MS could be repaired

By shedding light on how cells regenerate the myelin sheath surrounding nerve fibres in the brain, a new study published in Nature Neuroscience opens the door to treatments that could repair nerve damage and restore lost function in patients with multiple sclerosis (MS).
MS is a disease in which the immune system attacks and destroys myelin, the protein that insulates the nerves in the spinal cord, brain and optic nerve and stops the electrical signals from leaking out.
As the myelin is gradually destroyed, patients experience symptoms ranging from mild numbness in the limbs to paralysis or blindness.
The disease progresses not just because the immune system gradually destroys the myelin, but also because a natural repair process fails. Cells called oligodendrocytes are able to repair the myelin damage themselves - "remyelination" - but in MS this fails after a while.
There are over 400,000 living with MS in the European Union. There are currently no approved therapies that tackle the disease by promoting regeneration of the myelin.

Two immune cell findings may be important for future therapy

In this latest study, led by the Universities of Edinburgh and Cambridge in the UK, researchers describe how they studied immune cells called macrophages, known to be involved in remyelination, and found two important features that could lead to new therapies that promote myelin regeneration:
  1. For remyelination to proceed, macrophages have to become anti-inflammatory
  2. Macrophages release a protein called activin-A that actively encourages remyelination.
First author Dr Veronique Miron, of the Medical Council Centre for Regenerative Medicine at the University of Edinburgh, says in a statement:
"Approved therapies for multiple sclerosis work by reducing the initial myelin injury - they do not promote myelin regeneration.
This study could help find new drug targets to enhance myelin regeneration and help to restore lost function in patients with multiple sclerosis."
For their study, Miron and colleagues examined myelin regeneration in human tissue samples and in mice.
They wanted to understand what stimulates remyelination and which biological molecules, cells, or other factors may be involved that could serve as targets for regenerative treatments that restore lost vision, movement and other functions in people with MS.
Previous studies have shown that macrophages - immune cells that gobble up disease pathogens, debris and other undesirable materials, among other things - are also involved in regeneration.
For example, there is a group of macrophages called M2 that is essential for regenerating skin and muscle.

Hunt for potential drug targets

So what Miron and the team wanted to find out was whether M2 macrophages were also involved in myelin regeneration, and if so, were there particular molecules involved in stimulating remyelination that could serve as useful drug targets?
On examining a mouse model of human myelin damage and regeneration, the team found that M2 macrophages were present and increased in number when remyelination started. This suggests, they say, that M2 macrophages may control remyelination.
Previous research had already established that oligodendrocytes are the cells that normally produce the myelin found in the brain and spinal cord, so Miron and colleagues set about trying to discover if M2 macrophages were able to trigger the oligodendrocytes on their own, or whether they needed to work with another group of cells or processes.
To find out they put some oligodendrocytes in a test tube and exposed them to proteins released by M2 macrophages.
The result was a success. Exposure to M2 macrophage proteins spurred the oligodendrocytes to make more myelin.
The researchers also found that when they took M2 macrophages out of the equation, remyelination dramatically reduced, showing they were necessary for myelin to regenerate.
This was confirmed in further examinations of mouse models of remyelination, and brain tissue from people with MS. The researchers found in both cases that high numbers of M2 macrophages are present when remyelination is efficient, and the numbers are vastly reduced when it is not.
The team also found that a protein produced by macrophages, activin-A, contributes to the regenerative effects of M2 macrophages.
They found high levels of activin-A in M2 macrophages when remyelination was starting and also when they added the protein to oligodendrocytes in test tubes they started to make myelin.
To confirm the role of activin-A, the researchers blocked its effect on oligodendrocytes after myelin damage, and discovered the M2 macrophages were not as able to stimulate them to make more myelin.
They conclude that their findings point to a key step in myelin regenration, namely that when M2 macrophages release activin-A, they spur oligodendrocytes to make myelin.

Potential for synergistic drugs

The study suggests it may be possible to partner drugs that reduce the initial myelin damage, with ones that regenerate it in the central nervous system and thus restore lost functions in MS patients.
The researchers now plan to look in more detail at how activin-A works and whether its effects can be enhanced.
The study was funded by the MS Society, the Wellcome Trust and the Multiple Sclerosis Society of Canada.
In another study published earlier this year, researchers described how a new treatment for MS that resets the patient's immune system was found to be safe and well tolerated in a small trial.
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Future blindness cure? Stem cell success in lab

Scientists are one step closer to curing blindness, after they carried out the first successful transplant of light-sensitive photoreceptor cells from a synthetic retina that was grown from embryonic stem cells.
Researchers from University College London (UCL) and Moorfields Eye Hospital in the UK, transplanted the photoreceptor cells in to night-blind mice and found that the cells developed normally.
The cells integrated into the existing retina in the mice and formed the required nerve connections that transmit visual information to the brain.
The study, published in the journal Nature Biotechnology, shows embryonic stem cells could potentially be used to provide an "unlimited supply of healthy photoreceptors for retinal cell transplantations to treat blindness in humans."

The need for photoreceptor transplantations

Photoreceptors are light-sensitive nerve cells found in the retina of the eye. There are two types of photoreceptors - rods and cones.
The cones provide the eye's color sensitivity. The rods are not sensitive to color, but are more sensitive to light than the cones and are particularly important for providing the ability to see in the dark.
Photograph of an eye
Researchers say this study is one more step towards treating blindness.
According to researchers, the loss of photoreceptors in the eye is a leading cause of sight loss in degenerative eye diseases such as retinitis pigmentosa, diabetes-related blindness and age-related macular degeneration.
Last year, the team conducted research that involved transplanting photoreceptors into mice suffering from retinal degeneration, using cells taken from healthy mice with normal sight.
However, the researchers say that this method of transplantation would "not be practical for the thousands of patients in need of treatment."
Back then, the researchers said: "We are hopeful that we will soon be able to replicate this success with photoreceptors derived from embryonic stem cells and eventually to develop human trials."
Professor Robin Ali, of the Institute of Ophthalmology at UCL and Moorfields Eye Hospital, told Medical News Today:
"Much of this work has been done in mice in the past. Photoreceptor precursor cells taken from the developing mouse retina and pumped into adult mice shows that this can be effective in restoring vision for the mice that lack vision. This really gave the framework for our translation program. To make it practical, we needed to find a cell source from which we can get these photoreceptor precursors."
"We have been working on trying to find ways of repairing the retina by transplanting photoreceptor cells, and we have demonstrated proof of concept of that development. They are not stem cells, they are not fully mature photoreceptor cells, but they are immature photoreceptor cells."

How was the synthetic retina grown?

The researchers say the new technique was developed using 3D culture and differentiation of mouse embryonic stem cells, a method recently developed in Japan.
Retinal precursor cells were grown using the 3D culture method and they were closely compared to normally developed cells, with the researchers noting different stages of development.
The researchers also carried out tests to ensure that the genes being expressed by the two types of cells were "biologically equivalent" to each other.
From this, the scientists were able to grow the synthetic retinas "in a dish" which contain all the nerve cells need to provide sight.
Prof. Ali explains:
"What we have been able to do is build on work of a Japanese group from a study a couple of years ago, in order to make a synthetic retina from embryonic stem cells. We have adapted that and we have shown for the first time that we can use embryonic stem cells to make a retina in a dish."

No more "three blind mice"

The researchers injected around 200,00 of the artificially grown cells into the retinas of the night-blind mice.
Professor Ali and his research team
Professor Ali and his research team completed the first successful photoreceptor transplant using cells grown from a synthetic retina. Photo credit: UCL/MRC.
The study reports that three weeks after transplantation, the cells from the synthetic retina had "moved and integrated" within the the mice retina and began to look like "normal mature rod cells," which continued to be present after six weeks.
The researchers add that nerve connections (synapses) developed, meaning that the transplanted cells had the ability to connect with the existing connections within the retina.
Prof. Ali adds:
"This now means we have a cell source. This has all been done with mouse embryonic stem cells, but if we do it with human embryonic stem cells then we can do this for the first time using an embryonic stem cell source."
"That means we have got room to think about a human trial and repeat all this using human embryonic stem cells, and investigate whether we can repair the retina in conditions in which blindness is caused by loss of photoreceptor cells ."
Prof. Ali says that it will be a few years before this research will be used within a human trial, but the team have already started working with human embryonic stem cells.
He says:
"There are a number of ways that we can use this research to develop ways of treating blindness through gene therapy and artificial retinas. This is a very exciting approach because it has the ability to restore vision in patients who have very little vision, and the main cause of this in the developing world is loss of photoreceptors. Currently there is no treatment for that."
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Drinking coffee linked to lower suicide risk in adults

Drinking coffee is linked to lower suicide rates, suggests a study published in The World Journal of Biological Psychiatry.
Researchers from the Harvard School of Public Health (HSPH) reviewed data from three large US studies. This consisted of 43,599 men involved in the Health Professionals Follow-up study (HPFS), 73,820 women in the Nurses' Health Study (NHS) and 91,005 women in the NHS II.
The researchers analyzed data regarding consumption of caffeine, coffee and decaffeinated coffee every 4 years through food-frequency questionnaires, while the deaths from suicide were analyzed by physician review of death certificates.
The amount of caffeine consumption was assessed from both coffee and non-coffee sources, including chocolate, tea and caffeinated soft drinks. But the researchers add that coffee was the main source, accounting for a minimum of 71% in all three studies.
Over the study period, 277 deaths were a result of suicide.
Results revealed that the risk of suicide for adults who drank between 2-4 cups of coffee each day was 50% lower when compared with adults who drank decaffeinated coffee, very little or no coffee.
The researchers reported that there were no major differences in the risk of suicide between those who consumed 2-3 cups of coffee per day and those who drank 4 or more cups per day, but they note that this may be due to a smaller number of suicides in these categories.
Coffee cup and coffee beans
Researchers on this study say that the risk of suicide was 50% lower in adults who drank 2-4 cups of coffee each day. However, a previous study suggested heightened depression in adults who drank 4 or more cups of coffee per day.
However, the study notes that a previous study from HSPH analyzing how coffee was related to depression revealed that researchers saw a heightened depression effect in those who drank 4 or more cups per day.
The researchers report that as well as stimulating the central nervous system, caffeine acts as a mild anti-depressant by boosting the production of particular neurotransmitters in the brain. These include noradrenaline, dopamine, and serotonin. They add that this could explain the results of studies in the past that have linked the consumption of coffee to a lower risk of depression.
Regardless of the study's results, the authors say this does not mean the consumption of coffee should be increased.
The recommended coffee intake for the average healthy adult is around 2-4 cups per day. Experts advise that too much caffeine can have unpleasant side effects, such as insomnia, nervousness, restlessness, muscle tremors and a fast heartbeat.
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Eat breakfast to improve your heart health

A new study appears to confirm that when you eat is just as important for health as what and how much you eat.
US researchers asked men to complete questionnaires about what they ate and when they ate it, then tracked their health for 16 years. Those who said they skipped breakfast were found to have a higher risk of heart attack or fatal coronary heart disease.
Lead author Leah Cahill, of the Harvard School of Public Health (HSPH), and colleagues, write about their findings in a July 23rd issue of the American Heart Association journal Circulation.
In a statement, Leah Cahill, who is a postdoctoral research fellow in the department of nutrition at HSPH, explains what may lie behind the findings:
"Skipping breakfast may lead to one or more risk factors, including obesity, high blood pressure, high cholesterol and diabetes, which may in turn lead to a heart attack over time."
For their study the researchers analyzed food frequency questionnaires completed by 26,902 male health professionals aged between 45 and 82 years and tracked their health for 16 years from 1992 to 2008. The men were free of heart disease and cancer at the start of the study.
Over the follow-up, 1,572 men experienced non-fatal heart attacks or died of coronary heart disease.
When they analyzed the data the researchers found men who said they did not have breakfast had a 27% higher risk of heart attack or death from coronary heart disease than men who said they ate breakfast.

Men who skipped breakfast had other risk factors

The men who said they skipped breakfast tended to be younger, single, smokers, who worked full time, did not do much exercise and drank more alcohol.
The researchers also found when they adjusted the results to take out the effect of body mass index, high blood pressure, high cholesterol and diabetes, the links between skipping breakfast and higher risk for heart attack or death from coronary heart disease became much weaker: they were no longer statistically significant.
They note this suggests "eating habits may affect risk of coronary heart disease through pathways associated with these traditional risk factors."
They also found no links between how many times a day the men said they ate and risk of coronary heart disease.

Eating late at night linked to heart disease

They did find a link, however, between eating late at night and coronary heart disease. Compared with men who said they did not eat late at night, among those who did, there was a 55% higher risk of coronary heart disease.
But the authors note that, judging by the few men in the study who ate late at night, this was unlikely to be a major public health concern.
Leah Cahill says the message from the study, which reinforces previous research, is: "Don't skip breakfast." Eating a healthy meal at the start of the day is linked to lower risk of heart attacks.

Breakfast tips

Incorporate many types of healthy foods into your breakfast, Leah Cahill advises - as this is "an easy way to ensure your meal provides adequate energy and a healthy balance of nutrients, such as protein, carbohydrates, vitamins and minerals."
Bowl of breakfast cereal
Adding nuts and chopped fruit to cereal is "great way to start the day," the authors say

If eating a bowl of cereal, try adding nuts and chopped fruit, or steel-cut oatmeal. This is a "great way to start the day," Leah Cahill adds.
Senior author Eric Rimm, associate professor of medicine at the Harvard Medical School, says the team has spent decades looking at the effects of quality and composition of diet on health, and now this new study suggests overall dietary habits should also be considered in lowering risk of heart disease.
At a conference in 2012, UK scientists presented a study that explained why people who skip breakfast tend to find high calorie food more appealing later in the day: their brain circuits may be primed toward seeking it when fasting.

Comments from heart health charity

The British Heart Foundation's senior dietitian, Victoria Taylor, has responded to the current research news on breakfast benefits. She says:
"In the morning rush it can be all too easy to skip breakfast, but this study suggests this could have a bigger impact on our health than we might think.
However, these researchers only looked at men aged over 45, so we would need to see further research to confirm that breakfast has the same impact on the heart health of other groups of people."
Victoria Taylor adds: "What we do know is that a healthy and filling breakfast can make that mid-morning biscuit less tempting, as well as giving you another opportunity to widen the variety of foods in your diet.
"Wholegrain toast, or cereals like porridge with low-fat milk are a good way to start the day. Try a sliced banana or dried fruit on top and you'll be on your way to five-a-day before you've even left the house."
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