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FDA Approves First Bionic Eye

Argus II
Image Credit: Second Sight Medical Products

FDA approves first retinal implant for adults with rare genetic eye disease is good news. 

The Argus II Retinal Prosthesis System includes a video camera mounted on eyeglasses that transmits the image to a processing unit worn on the patient's belt that converts the image into signals that can be pulsed into the optic nerve.

It isn't Six Million Dollar Man quality (which would be $31 million today), because the electrodes only result in the spatial representation of light and dark.  Nonetheless, it is an amazing breakthrough because the patients can recognize large letters and street curbs.  It will help the patients identify the location and movement of objects or people.

The FDA approval is for adult patients with advanced retinitis pigmentosa (RP).  In a healthy eye, light-sensitive cells on the retina produce pulses to the optic nerve.  With RP, patients the light-sensitive cells degenerate, resulting in a loss of vision. 

Pretty amazing, isn't it?

 

Not So Good News About Strokes

Tracts of white matter in a mouse brain acquired with diffusion tensor imaging.
Image Credit: Susan Schwerin and LG Cohen

The National Institutes of Health explain a stroke is when the blood supply to the brain is suddenly interrupted or when a blood vessel inside the brain bursts.  The former is called a ischemic stroke whereas the latter is called a hemorrhagic stroke.

Long-awaited stroke studies show hopeful new treatment no better than older one explains that catheter removal of blood clot from a patient's brain is no better than the previous treatment of giving an IV does of clot-dissolving drug.  Physicians are discouraged, because it was hoped the new treatment would provide a superior treatment.

Providing additional information is Imaging acute ischemic stroke patients’ brains did not lead to improved outcomes.The trial was known as Mechanical Retrieval and Recanalization of Stroke Clots Using Embolectomy.  Patients underwent emergency brain scans to identify regions of the brain with decreased blood flow.  From the imagery, physicians then threaded a catheter to the site of a clot in the brain artery. 

But the news may not be all bad.  For the group of patients that have a large clot, Intravenous tissue plasminogen activator (t-PA), is not particularly effective.  For this group of patients, the new treatment may offer better treatment.

Two other stories about strokes today.  Southern diet has a tight grip on 'stroke belt' tells the southeastern U.S. has a 20 percent higher incidence of stroke.  Researchers believe that deep-fried chicken, fish, sweet tea, and other southern foods may explain the increased risk.

Bad news for pot smokers: double the stroke risk tells that in a New Zealand study, stroke victims between 18 and 55 were 2.3 times more likely to test positive for marijuana use than those that did not have a stroke.  In other words, smoking pot is beginning to look like it doubles the risk for a stroke.

 

The Difference Between a Sore Throat and Strep Throat

Note the moderate redness of the oropharynx, i.e., soft palate, and tonsillitis caused by group A streptococcus bacteria.
Image Credit: CDC

We know it as strep throat, but the docs know it as streptococcal pharyngitis, streptococcal tonsillitis, or streptococcal sore throat.

Is it strep throat?  tells that strep throat is spread by droplets from the patient's cough or sneeze.  Strep throat is caused by group A. Streptoccocus baceteria.  Other sore throats can be caused by postnasal drip and fungus, among other causes.

Strep throat can exhibit these symptoms:

• Sore throat, usually develops quickly
• Severe pain when swallowing
• Fever above 101 degrees F
• Red and swollen tonsils with white patches
• Swollen lymph nodes in the neck

Your doctor can use a swab of the throat to perfom a quick test for verification of strep throat.  If negative and your throat looks like the photograph, your doc may decide to perform a culture of the swab. 

If positive, antibiotics are typically prescribed, allowing you to feel better within 48 hours.  You should stay away from other people for the first 24 hours after beginning an antibiotic regimen to avoid infecting others. Wikipedia tells the antibiotic of choice in the U.S. is penicillin V, whereas amoxicillin is preferred in Europe.  Erythromycin is prescribed for those with penicillin allergies.

The best prevention - wash your hands!  It is spread by contact with an infected person's droplets.  Also, avoid drinking or eating after someone with a sore throat.

 

FDA Approves New Drugs for Type 2 Diabetes

Drawing showing how the pancreas responds to low or high blood glucose levels.
Image Credit: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH

Type 2 Diabetes was historically named non-insulin-dependent diabetes mellitus. Between 90 and 95 percent of adults with diabetes, have Type 2.  It typically begins with insulin resistance, or where the cells do not utilize insulin properly.  Eventually, as the body's cells require increasing amounts of insulin, the pancreas loses its ability to produce insulin.  Equally damaging is the high blood sugar levels which can lead to heart disease, blindness, and nerve and kidney damage.

Diabetes Type 2 was also known as adult-onset diabetes, because it is associated with older age, obesity, and family history. 

The best prevention against Type 2 Diabetes is lifestyle.  A healthy diet and physical exercise can reduce the probablity of Type 2 diabetes by 58 percent, and increases to 71 percent for adults over 60.

Control of blood sugar for Type 2 diabetics can reduce the chances of organ damage by 40 percent or more. 

FDA approves three new drug treatments for type 2 diabetes tells that three drugs are: Nesina, Kazano, and Oseni. All three drugs contain alogliptin, which helps to stimulate the release of insulin after a meal.  It was developed by the Takeda Pharmaceutical Company.

 

What is Causing Tau Protein in Football Players?

Loss of neuron connectivity due to tau protein
Image Credit: National Institutes of Health

I have blogged considerably about Alzheimer's Disease, because I fear it is an emerging pandemic for the world.  I am suspicious there is a correlation with all of the processed foods we are consuming, but so far there is not conclusive evidence.

We don't know the cause of Alzheimer's disease, but an indicator is abnormal amounts of the tau protein.  Scan may detect signs of NFL players' brain disease tells that tau protein has been identified in former football players. 

Previously, athletes subject to repeated concussions had be diagnosed with chronic traumatic encephalopathy (CTE) in an autopsy after death.  Although the tau protein is an indicator, along with neurofibrillary tangles, similar to Alzheimer's Disease, it is found deeper within the brain.  (With Alzheimer's, the protein is found in the cortex.)  Beta amyloid plaque, also an indicator of Alzheimer's Disease, is not a consistent indicator with chronic traumatic encephalopathy. 

The new study described in the CNN report tells that researchers were able to use a radioactive marker that attaches to tau protein similar to a PET scan for Alzheimer's Disease and were able to detect CTE in living athletes.  This is a first, because it allows early diagnosis of CTE. 

The reason for the abnormal production of tau protein and what to do with it, remains a mystery, as with Alzheimer's disease.

 

Developing a Therapy for Peanut Allergy

Peanuts!
Image Credit: Scott Bauer, USDA

Mmm.  I think peanuts go better with chocolate.  Most of us remember from elementary school that George Washington Carver popularized the peanut.  Wikipedia explains that post Civil War South's agricultural productivity was dismal after decades of wearing the soil out with the same crop of cotton.  George Washington Carver provided the South with an alternative crop to cotton with the peanut. 

Unfortunately between 1 and 2 percent of Americans have a peanut allergy.  It appears the human immune system reacts to peanuts as if they were a threat.  Symptoms can vary from hives and itching to life-threatening anaphylaxis, which includes throat swelling, a drop in blood pressure and other symptoms.  Because of Washington Carver's success with the peanut, it is difficult to completely avoid exposure to peanuts and the many products made with them.

Therapy Shows Promise for Peanut Allergy tells that a research team has been testing sublingual immunotherapy as a treatment.  Basically under medical supervision, a small amount of peanut powder is is placed under the tongue to decrease sensitivity to the allergen.  In the trial, 70 percent of the participants were able to eat ten times the amount of peanut powder after 44 weeks of therapy than before.  It was a small sample of volunteers, and more testing is required, but researchers were pleased such a simple therapy was so effective.  One thing though - if you have a peanut allergy, don't try this at home - obtain the assistance of a trained clinician. 

 

Vaccine Possible for Alzheimer's Disease?

The fibrous structures are amyloid plaques in brain tissue
Image Credit: Sherif Zaki; MD; PhD; Wun-Ju Shieh; MD; PhD; MPH

The National Institutes of Health has a new 2011-2012 Alzheimer's Disease Progress Report. 

You probably recall the human brain has billions of neurons, which receive and transmit information via electrical and chemical messages.  A neuron has a cable-like structure named an axon that communicates to a receptor structures named dendrites on nearby neurons.  There is an gap between axons and dendrites and the gap allows more than one neuron to receive a message called synapse from another neuron.  Perhaps as many as 7,000 neurons can receive a single message.

Alzheimer's Disease interrupts this communication between neurons.  When neurons become isolated, they die.  Although some loss of neurons happens with aging, the loss is much, much, greater with Alzheimer's Disease.  Unlike many other cells of our body, neurons do not replace themselves continually.  A neuron cell can live over 100 years.  To live this long, they have specialized repair mechanisms and ten times the number of neurons as helper cells within the brain.

Scientists do not know the cause of Alzheimer's Disease, but they have identified three common abnormalities.  First, there are amyloid plaques, or protein fragments that clump together.  Second are neurofibrillary tangles are clumps of protein within the neuron's cell body.  Third is the loss of synaptic connections which isolates the neurons.

Major Step Toward an Alzheimer's Vaccine tells that researchers have discovered a molecule which stimulate's the brain's repair mechanisms to more urgently remove amyloid plaque.  This molecule is known as MPL (monophosphoryl lipid A) and has been studied for several years.  Experiments with laboratory mice have been promising.

 

What to do when you catch a cold

Image Credit: National Institutes of Health

Wikipedia tells us the phrase, 'patent medicine' originated in the late 17th century.  It essentially meant that royalty approved the medical elixir.  (Surprisingly, WIkipedia adds that chemical patents were not granted in the United States until 1925.) 

Key to the patent medicine era was advertising.  The ingredients of the elixirs varied from worthless and harmless to harmful.  Wikipedia tells that some names that survived the patent medicine era include Coca Cola, 7-Up, Dr Pepper, Bayer Aspirin, Luden's Throat Drops and Vicks VapoRub.

Your child has a bad cold and feels awful?  Don't bother with those cold meds has some interesting recommendations.  Young children might catch a cold almost every month during the school year, while adults only suffer two to four times a year.  For children, the conclusion on over-the-counter medicine is, "there is no evidence of effectiveness..."  And guess what?  For adults, they might distract you from your cold. 

Cold remedies: What works, what doesn't, what can't help advises the single best remedy is fluids.  A salt water gargle can help a sore throat. 

Their recommendations for over-the-counter medicines?  They comment that pain relievers might offer some relief, but side effects should be considered.

Something that I discovered this evening, researching this blog - Pillbox by the National Institutes of Health.  It helps you identify an unknown pill with pictures.  Nice product.

 

FDA Issues Safety Announcement on Sleeping Pills

Image Credit: FDA

A couple of things about sleeping pills that you should know.  WebMD tells that a study showed sleeping pill users falling asleep 22 minutes faster than non-users.  Know why sleeping pills help you doze off tells of a study showing about half of sleeping pills benefit is because of the placebo effect.  In other words, the study concludes that sleeping pills work because you believe in them.

Mmm.  I'm skeptical of that study.  Zolpidem is the active ingredient in products such as Ambien, Ambien CR, Edluar, and Zolpimist.  Wikipedia tells that it generally works within 15 minutes and has a 2-3 hour half-life. Also, the medication can be effective in getting you to sleep, but not so effective in keeping you asleep.

Today the FDA issued a safety announcement on insomnia drugs.  The government agency first reminds the public that patients can suffer drowsiness and impaired driving the next morning after taking the medication the previous evening.  The newer extended-release medications are especially at risk. 

The warning in the announcement though, was a recommendation that physicians prescribe 50 percent lower dosages for women in the immediate release products and almost a 50 percent reduction in the extended release.  The announcement also suggested that the lower dosage for men should be considered as well.

Almost a year ago, I blogged, Sleeping Pills Much More Dangerous Than Expected.  There is a study that shows users of sleeping pills have a much higher incidence of sudden death.  Only 1-18 pills a year can result in a 3.6 times higher mortality rate. 

 

Flu Season In Full Swing

Image Credit: CDC

Best illustrated by the graphic on the left, flu season is in full bloom.  The CDC's FluView reports both influenza A and influenza B viruses are circulating, with with Influenza A about 4 times more prevalent.

Something that I found interesting is the second graphic, which shows when most people receive their flu vaccinations.  As shown, not many people are vaccinated by early flu season.  (I''m still impressed though, by the coverage of vaccination.  Almost 50% for the population is pretty good for a voluntary vaccination.)

The first line of defense against the flu is to be vaccinated before being exposed to the virus. The second line of defense is antiviral drugs, which must be taken within 2 days of becoming infected.  So far this season, anti-viral medications oseltamivir and zanamivir are effective for most cases.  There are some 2009 H1N1 and H3N2 variants appearing that are resistant to the anti-viral drugs.  The CDC's information on antiviral drugs tells that generally they only shorten the time you are sick by 1 or 2 days.  In addition, there are some side effects.  But for individuals with high risk medical conditions, they could prevent a hospitalization.