Light-powered bionic eye invented to help restore sight

A retinal implant - or bionic eye - which is powered by light has been invented by scientists at Stanford University in California.

Implants currently used in patients need to be powered by a battery.

The new device, described in the journal Photonics, uses a special pair of glasses to beam near infrared light into the eye.

This powers the implant and sends the information which could help a patient see.

Diseases such as age-related macular degeneration and retinal pigmentosa result in the death of cells which can detect light in the eye.

Eventually this leads to blindness.

Wiring eliminated

Retinal implants stimulate the nerves in the back of the eye, which has helped some patients to see.

Early results of a trial in the UK mean two men have gone from being totally blind to being able to perceive light and even some shapes.

However, as well as a fitting a chip behind the retina, a battery needs to be fitted behind the ear and a cable needs to join the two together.

Prof Robert MacLaren from Oxford Eye Hospital explains how a bionic eye implant works

The Stanford researchers say their method could be a step forward by "eliminating the need for complex electronics and wiring".

A retinal implant, which works in a similar way to a solar panel, is fitted in the back of the eye.

A pair of glasses fitted with a video camera records what is happening before a patient's eyes and fires beams of near infrared light on to the retinal chip.

The creates an electrical signal which is passed on to nerves.

Natural light is 1,000 times too weak to power the implant.

The researchers said: "Because the photovoltaic implant is thin and wireless, the surgical procedure is much simpler than in other retinal prosthetic approaches.

"Such a fully integrated wireless implant promises the restoration of useful vision to patients blinded by degenerative retinal diseases."

The implant has not been tested in people, but has been shown to work in rats.

Exercise Reduces Breast And Colon Cancer Death Rates

A study in the May 8 edition of the Journal of the National Cancer Institute reveals that physical activity is linked to lower rates of breast and colon cancer deaths. However, there is not enough evidence to link physical activity to other types of 


Cancer survivors are able to enjoy a longer life due to improved cancer therapies and screenings and they frequently study information on how life factors, such as exercise, can affect their prognosis. Various observational studies and randomized control trials (RCTs) have evaluated the potential impact of physical activity on cancer survivors.

Rachel Ballard-Barbash, M.D., of the Applied Research Program in the Division of Cancer Control and Population Sciences at the National Cancer Institute and her team reviewed 45 articles of observational studies and randomized controlled trials (RCTs), published between January 1950 and August 2011, that examined the relationship between physical activity and cancer mortality and/or cancer biomarkers amongst those who survived the disease. They discovered that the RCTs with biomarker endpoints indicate that exercise is potentially beneficial in terms of the survivors' insulin levels and also reduces inflammation and may improve immunity.

The strongest evidence was found in those who survived breast cancer, followed by those who survived colorectal cancer. Most studies displayed a statistically considerably decreased risk of breast cancer and all-cause mortality related to exercise.

The researchers highlight the fact that due to the diversity of the various studies, specific recommendations in terms of exercise types or timing cannot be made, however, they do confirm that exercise contributes to the cancer survivors' overall safety and to their physical and mental benefits. 

They continue saying that future RCTs should examine various types of exercise, including how obesity, weight loss and cancer treatments may impact the effects of exercise on biomarkers, as well as how exercise may influence comorbidities in cancer survivors.

Edward L. Giovannucci, M.D., ScD, of the Department of Nutrition at the Harvard School of Public Health writes in a linked article that physical activity may prolong cancer survivor's life span and their quality of life, writing:

"Even though direct effects of physical activity on cancer are not definitely proven, given that physical activity is generally safe, improves quality of life for cancer patients, and has numerous other health benefits, adequate physical activity should be a standard part of cancer care."

Children with cerebral palsy may benefit from playing video games

According to a study published online in the Archives of Physical Medicine and Rehabilitation, children with cerebral palsy (CP) may benefit from playing active video games (AVG), such as Nintendo's Wii. 

The researchers found that not only did children enjoy playing AVGs, the games can also help children attain moderate levels of physical activity and could potentially be used in rehabilitation therapy.

Lead researcher Elaine Biddiss, Ph.D., of Toronto's Bloorview Research Institute at Holland Bloorview Kids Rehabilitation Hospital, and the University of Toronto, Canada, explained:

"Active video games (AVG) provide a low-cost, commercially available system that can be strategically selected to address specific therapeutic goals.

While our results did not show that AVG game play can be regarded as a replacement for more vigorous physical activity or muscle strengthening, we found that some games may provide targeted therapy focused on specific joints or movements."

The researchers examined 17 children with CP whilst they played four AVGs: Wii Boxing, Tennis, Bowling, and Dance Dance Revolution (DDR). The team recorded data on energy, muscle activity and motion. Study participants were given a survey in order to mark their level of enjoyment playing the games.

In addition, the team assessed the therapeutic potential of AVG play, the intensity of the physical activity, as well as the practical considerations surrounding the of active video games to promote physical activity. 

The researchers found that although the games were not vigorous enough to build endurance or strength, children with mild CP were able to attain moderate levels of physical activity with games such as Wii Boxing and DDR that require full body movements. 

According to the researchers, AVG play could promote neuroplastic change as they encourage repetitive movements and provide feedback to the player via on-screen game scores and avatars. The children rated enjoyment levels of AVG game play as high, which also improves neuroplasticity.

Wii Boxing may be a good choice for encouraging and training faster wrist movements, the researchers note, which is vital, as children with GP often have difficulty extending their wrists. 

Furthermore, the team found that children with hemiplegia (a form of CP that affects the limbs on one side of the body) who played Wii Boxing or DDR engaged both upper limbs when playing.

Dr. Biddiss said:

"Wii boxing, or similar games, may be an effective motivational environment for encouraging increased movement speed of the hemiplegic limb, in addition to the bilateral use of the limbs, because in-game success is strongly linked to these two metrics."

According to the researchers, the range of motion of the dominant limb was well within the typical norms associated with upper limb movements in able-bodied individuals.

Although further studies regarding safety are required, this study indicates that AVG should be a fairly low impact activity for children with the disorder.

The team found significant differences in the strategies used by the children to succeed in the game. They discovered that children may adapt a movement that reduces physical effort in order to maximize in-game rewards. In a therapeutic setting, it may be necessary to train and provide rewards for appropriate movement styles.

Dr. Biddiss concludes:

"While not a replacement for structured exercise and physical therapy, AVGs may encourage children with CP to be physically active and to practice complex motor activities.

There are many opportunities for further research. Further development and optimization of AVG technologies may usher in a new age in physical rehabilitation where virtual environments provide an arena for neuroplastic change in the comfort of one's home."

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Here are some clues on How to Be an Active Patient.

People who are actively involved in their medical care stay healthier, recover quicker when they're ill and live longer, healthier lives, says the Agency for Healthcare Research and Quality.

Active patients participate as partners in their health care with their doctors and other providers. They don't make health care decisions on their own, but they're in charge of the process because they schedule appropriate visits to their health care providers, plan ahead to get the most out of those visits, learn about their conditions and medications, and follow through on treatments and lifestyle changes as agreed upon by them and their doctors.

Being informed about any health conditions you have can keep you from passively agreeing to tests and treatments.

Decide what you want to get out of an appointment before you walk into the office. Write down any questions you have and any issues you want to discuss beforehand. Bring your notes and refer to them.

Other ideas:

• Bring a list of all the prescribed and over-the-counter drugs, herbs, and supplements you take and note your dosages.
• Bring a list of any medicines to which you are allergic.
• Keep a health diary. If you have a chronic condition or specific health concern, make a dated log of your general health, taking special note of symptoms or changes. This will remind you to discuss certain things with your health care provider and also will help him or her chart any change in your symptoms over time.
• If you're seeing a new health care provider or a specialist for the first time, bring copies of your medical history and information on diseases, conditions, and cause of death of family members. This will help build your medical profile and put your current state of health into perspective. Write or call your previous health care provider and request that copies of your records and lab and X-ray reports be given to you or sent directly to the new provider.

Schedule and keep appropriate medical appointments.

Answer your health care provider's questions completely and truthfully. For example, if you're worried you'll have difficulty with a suggested treatment, say so.

Avoid saying what you believe your provider wants to hear. If you don't think your treatment is helping you, speak up. Share your fears and concerns about your condition. Ask what to expect while you're getting better and how long your provider thinks it will take before your illness is cured or your symptoms are under control. It's essential to speak openly about symptoms because your doctor uses the information you provide to make a diagnosis and determine a treatment plan. Plus, a problem will remain untreated if you don't discuss it.

Other ideas:

• Follow your provider's instructions. For example, be sure to take any medicine prescribed, as scheduled, and follow any other physical and dietary regimens he or she recommends. If you feel worse or you don't believe the treatment is working, call your doctor immediately. This feedback will help the two of you work together to adjust your treatment and find therapies that work best for you.
• Listen closely. Listening carefully to what your provider says about your condition is as important as giving him or her an accurate assessment of your health. Take notes during your visit if you think you may forget part of your treatment regimen.
• Be ready to answer specific questions. Your provider needs to know your specific symptoms, when they started, and if they appear at certain times of the day or after certain activities, such as eating.
• Advise your health care provider if you're pregnant. This will affect the treatment a physician recommends.
• Take all medications as directed. Follow drug dosages precisely. Taking more of a medication could be dangerous; taking less could delay your recovery.
• Make positive lifestyle changes to reinforce your medical treatment. Stop smoking, limit your alcohol intake, improve your diet, get enough rest, and exercise regularly; these can improve your immunity and your body's ability to heal itself.

Understanding your condition can help you manage and control chronic illnesses, such as asthma or heart disease.

Ask your health care provider to recommend additional sources of information if you want to know more about your condition. Libraries, valid Internet sites, support groups, and associations can be helpful. Be aware that advice given on some health-related Web sites and chat rooms may be hearsay.

If you have a serious condition, ask if there are other treatment options besides the one your doctor recommends.

You have a right to get the information you need to make decisions about your care.

This information may include:

• Explanations of the purpose of tests and procedures that may be costly, painful, or risky
• Explanations of the purpose and expected effectiveness, and side effects of treatments
• Clarification on any medical advice or words you don't understand

One of your doctor's primary roles is to prescribe and monitor your medication use. Your responsibility is to take the right amount at the right time.

Be sure you know the following before taking a prescription or OTC medication, herb, or supplement:

• The medicine's name and what it's supposed to do
• How often you should take it
• Any medicines, foods or beverages to avoid when taking it
• Its possible side effects
• What you should do if you forget a dose

Depressed Kids Need Help

A new label on some antidepressants, a so-called black box warning, cautions that they may make kids feel more suicidal. But that warning shouldn't stop parents from considering their use for depressed teens, psychiatrists say.

In short, teen depression is a serious illness. The benefits of getting help, including taking medications if needed, far outweigh the potential risks.

A specific group of antidepressants called selective serotonin reuptake inhibitors (SSRIs) has been shown to help children and teens with depression, according to the National Institute of Mental Health (NIMH). The black box warning applies to these SSRIs and the U.S. Food and Drug Administration (FDA) says that suicidal thoughts or behavior are more likely in the first four weeks of use or when dosages are changed. Psychiatrists say the warning was meant, in part, to alert other doctors and parents to the need for closer monitoring.

The FDA says that children and teens who begin taking SSRIs should be closely watched for any worsening of depression, suicidal thoughts or behavior, or any unusual changes in behavior, including sleeplessness, agitation or withdrawal from social situations.

Antidepressants don't work in every case. Prozac, for example, helps only about two-thirds of those who take it, the FDA says, and some children experience side effects such as agitation.

Suicidal thoughts are very common in adolescents. Fortunately, few succeed. Usually, they don't tell anybody about it.

Studies involving about 4,400 depressed kids led to the new warning. Those who took antidepressants were twice as likely to express suicidal thoughts as those who took placebos (sugar pills). The numbers were small—4 percent for those on the drugs versus 2 percent on placebos. There were no actual suicides.

If you think your child might have depression, don't worry about trying to define what it is, just get it checked out. See a mental health professional and get a comprehensive evaluation. The good news is that if it is depression, most kids can be helped.

Here are some suggestions from the NIMH:

• Realize that depression in your child or teen is a serious condition that should be treated and monitored.
• Your child should be thoroughly evaluated by a health care provider to determine if medication is appropriate. If an SSRI is prescribed, the child should be closely monitored, particularly during the first four weeks. And if suicidal thoughts or agitation develop, notify your provider at once.
• Medications are not the only treatment for depression, but are usually required if the depression is more than mild. Many times psychotherapy is given as the first treatment for mild forms of depression. For more severe forms, medication may be given in combination with psychotherapy.
• If your child expresses suicidal thoughts or behavior or even intimates these, or has nervousness, agitation, irritability, sleeplessness or easily changeable moods, have him/her evaluated without delay.
• If your child is already taking an SSRI, he/she should not stop taking the medication without discussing it with a health care provider. The child also should continue to be monitored to see that the medication is helping.
• Realize that any medication may have side effects. Talk to your health care provider if you have concerns about side effects.

Why is the Doctor pressing your abdomen? check it out.

For those trained in such touching, pressing on your abdomen can provide significant clues to potential problems.

The external examination with the hands gives doctors information about such important structures as the liver, spleen, kidneys, intestines, pancreas, bladder, gallbladder, appendix, abdominal aorta (the major blood vessel from your heart to your legs), and in females, the uterus and ovaries.

When the doctor presses on your abdomen, he or she is feeling to see if any of these are enlarged or tender, making them painful to touch, which could indicate disease.

Doctors use two different techniques to examine your abdomen: palpation and percussion.

A diagnosis is rarely made from only a manual examination of the abdomen, but this procedure can turn up what appear to be abnormalities, warranting further examination or testing.

Palpation means pushing down to see if the organs can be felt. For example, the aorta that supplies blood to the lower extremities runs directly beneath the navel and should be only an inch wide; if it is wider than that, there could be a problem such as an aneurysm.

The doctor also looks for tenderness, or pain that you experience when he depresses then quickly lifts his hands off your stomach (rebound tenderness). Such pain indicates that the peritoneum, or the membrane that lines the abdominal cavity, is inflamed--as often happens when the appendix becomes diseased, the bowel is perforated or there is peritonitis.

Then there's the spleen. If you're a healthy adult, the doctor shouldn't be able to feel it. If he can, that means the spleen is enlarged. The next step is finding the reason for the enlargement--possibly disease, such as infectious mononucleosis or leukemia.

Percussion means tapping the abdomen and listening to the sounds. It's similar to the tapping done by shoppers who know a ripe watermelon sounds different from an unripe one. When the doctor taps below the rib cage, he can hear the sounds made by a normal liver. But when he taps beyond where the liver should extend, the same sound could indicate an enlarged liver. Fluid in the abdominal cavity (ascites), a result of heart, liver or kidney disease, can sometimes be detected by percussion.

Why the Doctor Asks for your Urine Sample.

It's probably safe to say that no one really likes giving a urine sample. But the fact is that few tests can match the routine urine analysis for telling your doctor about what's going on inside your body.

The bladder can hold almost 2 cups of urine for two to five hours comfortably, and excretes about 2 quarts of waste products and additional water daily. And just as you use a dipstick to check your car's engine oil, doctors rely on a specially treated "dipstick," a plastic stick that has segments imbedded with different chemical indicators on it, to test urine. Unusual amounts of certain substances in your urine can indicate conditions ranging from minor urinary tract infections to diabetes and other more serious conditions.

One portion of the dipstick, for instance, measures the specific gravity (a measure of the amount of substances dissolved in the urine). The higher the specific gravity, the more concentrated the urine is. Using a numerical scale, the dipstick shows whether you're drinking enough fluids and how well your kidneys are filtering wastes from your body. Very concentrated urine suggests you are probably not drinking enough fluids, making it harder for your body to flush wastes. Urine is normally darker--more concentrated--in the morning, because your body's been storing wastes all night.

The dipstick registers the presence of a variety of chemicals that the kidneys filter, such as glucose (sugar) or minerals. Healthy people generally don't excrete sugar in their urine. Its presence may mean that you have diabetes or another condition that prevents your body from efficiently converting blood sugar into energy.

The urine test also can indicate infections by measuring nitrites and leukocytes. Bacteria produce an enzyme that converts nitrates, which are normally present in urine to nitrites. Leukocytes are the white blood cells that fight infection. The presence of either indicates that your body may be fighting an infection in the bladder or somewhere else along the urinary tract. They also can indicate something even more serious, such as a tumor, but further tests are needed to confirm these findings.

The dipstick gauges protein and pH levels. Urine shouldn't contain much, if any, protein, although some perfectly normal people do excrete tiny amounts. Urine pH, or acidity, normally ranges between 4.5 and 8, with most people's urine falling between 5.5 and 6.5. Significantly high protein or pH levels can suggest kidney or other renal dysfunction.

Ketones can be detected by dipsticks. They are substances produced when fat is used by the body for energy. They are eliminated from the body in the urine. Large amounts of urinary ketones indicate a diet low in carbohydrates, starvation, or, in a person with diabetes, a dangerous condition known as diabetic ketoacidosis.

Advantages and Disadvantages of having a home birth

Can I have a home birth?

You can 'book' a home birth with your GP, or direct with a community midwife. You can also do this through an independent midwife, although you will have to pay.

There are some health and pregnancy issues that make a home birth less suitable for some women, but it’s still your choice. Things you need to think about before reaching a decision are:

Advantages

• You'll be in a familiar, relaxing and private environment
• There should be no quick dash to hospital once you go into labour – you can stay put
• You can choose who you want there during labour, so if you want your other children around that's fine
• You may feel more in control at home
• After your baby's born, you can get into your own bath and your own bed

Disadvantages

• There may be fewer options for pain relief at home
• You may have to transfer to hospital if there are complications and this may be an issue if you live some distance away
• There is no emergency paediatric care on hand if your baby needs it

How do I arrange a home birth?

Once you've had your pregnancy confirmed, talk to your GP or midwife about a home birth. They'll discuss your choice and make the necessary arrangements.

If your GP's concerned about your choice, contact the manager of your local community midwifery services.

The earlier in your pregnancy you decide on a home birth, the easier it is to arrange one, and you can change your mind and opt for a hospital birth at any point.

Once labour begins, your community midwife may visit you once, twice, or more. When your baby's birth is imminent she'll stay with you.

Will I need any special equipment?

Your midwife will bring all the equipment she needs. You don't need to provide very much, but you should ensure your home is warm.

You'll need:

• Plastic sheets to protect your bed and carpet
• Warm towels and warm clothes for your baby
• A bright lamp so the midwife can see what she's doing
• A packed overnight bag, including baby clothes, in case you need to be transferred to hospital

If you'd like to use a birthing pool at home, these are available for hire.

What if I need to go to hospital?

If there are complications during your labour, the midwife may decide you or your baby would be safer in hospital.

She'll discuss this with you and your partner, and will call an ambulance. She'll go with you and may continue with your care depending on how many hours she's already worked.

If you use an independent midwife she may not be able to assist you at the hospital, although she can remain with you as a supporter.

After a home birth

Your midwife will stay for some time after the placenta has been delivered, and will check your baby and help you to breastfeed.

Your midwife, or one of her colleagues, will visit you every day for a few days and your GP will carry out a complete check on your baby.

Disclaimer

All content within Ask-Med-Blog is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. Ask-Med-Blog is not responsible or liable for any diagnosis made by a user based on the content of this Blog. Ask-Med-Blog is not liable for the contents of any external internet sites listed, nor does it endorse any commercial product or service mentioned or advised on any of the sites.  Always consult your own GP if you're in any way concerned about your health.

3D images may help treat cancer

Three-dimensional images of tissue samples could help spot cancer early, say researchers.

Scientists from the University of Leeds have created a technique to generate hi-resolution, colour 3D images of a piece of tissue.

The images can be rotated on a computer screen and examined from any angle.

Cancer Research UK said the technology could help researchers understand how cancer grew and spread, and learn how to treat it more effectively.

The findings are published in the American Journal of Pathology.

Digital microscopy is not new - tissue scanning first appeared a decade ago, replacing the conventional method of manually cutting ultra-thin slices of tissue one by one to then examine them under a microscope.

But these scanners, which are now used around the world, produce two-dimensional images, revealing only one cross-section of that particular piece of tissue.

And this has drawbacks, according to Dr Derek Magee, one of the researchers involved in the study.

Realistic image

"The tissue is of course three-dimensional, and in a lot of applications this three-dimensional nature is important," he told BBC News.

"For example, if you take a blood vessel, which is a branching network of tubes, and you take a slice of it, the 2D image that you get is an ellipse.

"This tells you absolutely nothing about the connectivity, or the specific branching, of that particular network of blood vessels, which could be particularly important for cancer specialists."

A 3D image could help provide much more information than a simple 2D scan.

To create one, a piece of tissue must be cut with an ultra-precise machine called microtome into hundreds of very thin slices.

Each slice is then put onto a 1mm-thick piece of glass and loaded into a digital scanner.

The scanner then creates 2D impressions of each cross-section, and this is where the new technology comes into play.

The software developed by the Leeds University team generates a three-dimensional shape from these virtual slides, creating a realistic image that a researcher can manipulate and spin around.

Spotting cancer

"This may help spot small tumours that could be missed by conventional approaches," said Dr Magee.

"Also, if there is a major blood vessel fairly nearby, it will be possible to see if a tumour has reached it.

"And if it has not, you can probably cut it out very safely."

It is the same with organs, added Dr Magee - if a surgeon wants to remove a tumour near a very sensitive organ, the main question is about the safety of the procedure.

It is also possible to reconstruct 3D images of whole sections - as seen with this mouse embryo, created with 200 slides

This technology could help researchers understand more about the disease, and how to treat it more effectively, said Dr Kat Arney, science information manager at Cancer Research UK.

"We're beginning to understand just how complex cancer is," she told the BBC.

"A tumour is a complex three-dimensional 'organ' made of cancerous and healthy cells, including blood vessels, immune cells and other 'normal' cells.

"It will be fascinating to see how this exciting new technique is taken forward by cancer researchers, and what secrets it can yield about the disease."

In the past, there have been attempts to create 3D images of tissue samples.

But the images were low resolution and hence not very detailed, generated after taking photos of slides on a microscope with a camera, one by one, and then assembling them digitally.

But the Leeds University team said that their approach was the first time a standard digital scanner had been used to produce high-resolution images.

"Up until now, the use of 3D imaging technology to study disease has been limited because of low resolution, and the time and difficulty associated with acquiring large numbers of images with a microscope," said lead researcher Dr Darren Treanor.