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Month: December 2011

Dear Doc: One-time flu shot in the pipeline?

Dear Doc: One-time flu shot in the pipeline?

Dear Dr. K: I heard there is work being done on a one-time flu shot. Is this true?

Yes, Virginia, there is a Santa Claus and with any luck, there may also be a one-time flu vaccine. Before I discuss this new research let me review the current vaccine.

Traditional influenza vaccines target the globular outer region of the viral hemaggluttinin protein. This part of the protein is constantly changing and accounts for the new strains of flu seen each year. Moreover, for each year’s vaccine to work, scientists must accurately predict these new strains so that the vaccine is effective.

The new vaccine research is targeting the stem of the hemaggluttinin protein, which rarely changes. This stem protein is found across the board in all influenza strains. Thus, eliciting antibody production to this common protein will create broadly neutralizing immunity to all flu viruses. Therefore, one vaccine will prevent all types of flu.

Researchers have already tested this vaccine in mice and it protected them from a lethal dose of flu. If further tests in animals have success, human studies will soon follow.

Indoor plants: Put ‘em to work

Indoor plants: Put ‘em to work

Household HVAC (heating and air conditioning) systems use filters that are good for removing particles such as dust, mold and pollen, but have no benefit for removing volatile pollutants.

There are chemical filters that are produced, but they are extremely expensive and beyond the budget of most private households. Such filters typically are used for special clean-room research or in NASA’s space vehicles.

Indoor plants offer a viable alternative to man-made filters. The most common indoor pollutants that can cause respiratory harm are formaldehyde, benzene and trichloroethylene.

The most common sources of formaldehyde are carpeting, particle board, new clothing, foam insulation, plywood and some household cleaners.

Sources of benzene are tobacco smoke, gasoline, synthetic film, plastics, inks, dyes, some detergents and resins. Sources of trichloroethylene are dry cleaning, inks, paints, varnishes, lacquers and adhesives.

Certain plants are more effective at removing one chemical than another. The plants that work best for formaldehyde are spider plant, ivy, aloe vera, Boston fern, ficus and schefflera. The best plants for benzene are ivy, peace lily, peperonia, daisy and chrysanthemum. The best plants for trichloroethylene are arrowhead, dracaena, ivy, mother-in-law’s tongue and parlor palm.

As you may have noted, ivy plant leaves do have the broadest spectrum of chemical absorption.

Keep in mind that plants cannot only remove harmful chemicals, but they also add oxygen to the air.

Even in food families: we get along with some relatives better than others

Even in food families: we get along with some relatives better than others

Food families have similar proteins and this can lead to cross-reactive allergy. That having been said, not all families have the same degree of cross-reactivity.

Peanut allergy is often severe but, luckily, has one of the lowest levels of cross-reactivity with other legumes. There is only a 5 percent risk of cross-reactivity for peanut with beans, peas and soybeans.

Cow-milk allergy is the highest (at 90 percent), with other mammals and milks from sheep and goat. Yet, people with cow-milk allergy almost never react to mare’s milk, donkey’s milk or dolphin’s milk.

Shellfish cross-reactivity is high at 75 percent. Thus if an individual is allergic to shrimp, he or she has a three in four chance of also being allergic to lobster, crabs or crawfish. This high degree of cross-reactivity is not true for non-crustacean shellfish such as clams and oysters.

Fish cross-reactivity is roughly 50 percent.

Tree nut allergy is about 35 percent cross-reactive across the board. However, certain nuts seem more closely linked. Pistachio is very similar to cashew, walnut to pecan and almond to hazelnut. Nut allergy does not translate to seed allergy such as sesame seed, but sesame, poppy and sunflower tend to be cross-reactive with one another.

On a practical level, if an individual with a specific food allergy has already tolerated other foods in the same family, that person should continue to be safe in eating these family-related foods. Still, foods in the same family that have not yet been tried should be considered suspect, and the individual may want to undergo allergy testing to determine the safety of the particular food.

Add one to the OK list for coffee and tea drinkers

Add one to the OK list for coffee and tea drinkers

 Coffee and tea have long been known to have antimicrobial benefit. Because of this knowledge, researchers at the Medical University of South Carolina decided to study whether drinking these beverages impacted the carrier rate of methicillin-resistant Staphylococcus aureus, the multi-drug-resistant staph infection known as MRSA.

An estimated 3-million Americans are carriers of MRSA. This represents almost two percent of the population. By monitoring nasal swab cultures, the university scientists were able to demonstrate a 50 percent reduction in carrier state of MRSA in individuals who drink coffee and or tea. No reduction in carrier state was seen in people who drink sodas, even if they contain caffeine.

For millions of asthmatics, hopeful gene therapy studies

For millions of asthmatics, hopeful gene therapy studies

The lead article in The New England Journal of Medicine in September discussed novel research on genetic variation in asthma. More than 300-million people worldwide have asthma, and up to 20 percent of these show poor or no response to corticosteroid medication, which is usually their main controller medicine.

Researchers at Harvard speculated this lack of response to corticosteroid medicines might be genetically linked and they sought to find the gene.

By screening 530,000 single-nucleotide polymorphisms (SNPs – pronounced snips) in a large group of asthmatics they discovered one SNP called rs37973 that showed up in the non-steroid responders. Furthermore, they discovered that rs37973 decreases the effectiveness of gene GLCCI-1, which is the gene that controls response to steroids.

Their hope is that new therapies will soon be discovered that “up-regulate” (turn on) the depressed GLCCI-1 gene.