Stories tagged Life Science

Oct
08
2007

Brain-eating buggers: Shown here are 1000 times magnification, Naegleria fowleri amoebas are embedded in and eating away at brain tissue. Six people in the U.S. this year have been died from having the amoebas get into their heads.
Brain-eating buggers: Shown here are 1000 times magnification, Naegleria fowleri amoebas are embedded in and eating away at brain tissue. Six people in the U.S. this year have been died from having the amoebas get into their heads.
This sounds like it could be the story arc for the movie Halloween 18, but it’s a real situation that has become a living nightmare for a handful of families living in the southern U.S.

Six people have died this season after encounters with Naegleria fowleri, a microscopic amoeba. Here’s the real horror movie part of the story, the deadly amoebas get sucked up the nose of the victim, work their way into the brain and feed on brain tissue until the host dies.

This year’s six reported deaths is a huge spike in cases that the Centers for Disease Control and Prevention have monitored. From 1995 to 2004, there were 23 people killed by the condition in the U.S. This year’s cases include three in Florida, two in Texas and one in Arizona. Naegleria fowleri was discovered in Australia in the 1960, and worldwide, there have only been a few hundred cases reported.

In Arizona, a 14-year-old boy had been swimming in Lake Havasu prior to developing headaches. They persisted for days, and no remedies were found even after going to the hospital, where the boy died nine days after swimming.

The deadly amoebas like warm water and live in lakes, warm springs and even swimming pools. A common pattern to exposure has people wading through the warm waters, stirring up the bottoms where the amoebas live and then getting some of that amoeba-infested water up their nose. Swimming or diving into that water could also provide exposure to the amoebas.

To make matters worse, there isn’t any clinical treatment for the condition. While several drugs have killed Naegleria in the lab, they’ve been ineffective when used to treat humans. Most cases involving humans have resulted in death.

Local government agencies in the areas where people have died are organizing education campaign in their communities about the condition. A fact sheet on Naegleria folweri is also available on the CDC website.

Oct
08
2007

Deer danger: The coming of fall also means the coming of greater risk for hitting a deer while you're driving on the roads. During mating season, deer are more active and less alert. (Photo from the oops list)
Deer danger: The coming of fall also means the coming of greater risk for hitting a deer while you're driving on the roads. During mating season, deer are more active and less alert. (Photo from the oops list)
It’s that time of year again when young deer’s thoughts turn to romance.

Fall is the season when deer are mating and they don’t have all their wits about them, kind of like the people hanging out in downtown Minneapolis late on Friday and Saturday nights.

What that means is that fall is also the prime time for car/deer collisions. I’ve been through several of these personally (I even hit two deer at once one time) and it’s not fun.

The Minnesota Department of Natural Resources reports that we have about 19,000 auto/deer collisions each year. Those result in around 450 injuries to humans and two deaths, on average.

On top of that, it’s not cheap to hit a deer. The average cost per insurance claim for collision damage is $2,800. If someone gets hurt, that average climbs to $10,000.

Fall is the peak time for the deer to be moving with November and December being the prime times. Here are some tips on how to deal with, and reduce, your exposure to smacking a deer on the road.

• Pay attention to deer crossing signs. They’re put up in places that traditionally have a lot of deer activity.
• Be especially aware around sunrise and sunset. That’s when deer are most often on the move.
• If you see a deer, be extra alert. There’s usually more. Deer usually travel in groups.

If you see a deer on the road:
• Slow down and blast your horn with a long blast to make it move.
• Brake firmly, but don’t leave your traffic lane. More serious accidents involving deer happen when drivers try to swerve to avoid hitting the deer, resulting in hitting other cars or obstacles along the road.
• Always wear a seatbelt. Most injuries in car/deer collisions could have been avoided by wearing a seatbelt.
• Don’t count on deer whistles, fences or reflectors to prevent deer from getting in your path. There is no proven information on these items reducing deer collisions.

Do you have a deer crash story? Let us know about it here at Science Buzz.

Oct
05
2007

I was looking around at the number of people that visit which stories on our website this morning and noticed a huge spike in traffic to this story we wrote back in 2006 on Boxelder bugs. Just yesterday alone the number of people searching for the story went from an average of 40 people to about 250 in one day. This got me wondering, are you starting to notice that seasonal invasion of these bugs?

Leave a comment here to tell us about your box elder stories. 2006 was a big year for the little buggers and I wonder what differences you might see this year.

Oct
03
2007

Lately it seems like no newscast is complete without a story about a recall of toys that could be lead-poisoning risks to kids. We get the details of what toys are impacted, but we rarely get the details on how they’re dangerous. Do you know the threats lead-tainted toys pose to kids’ health?

Tasty, but possibly dangerous: The US government has banned or limited lead in consumer products—like children’s jewelry or paint on toys—but toys made in other countries may not meet US safety standards. (Photo courtesy Tim Brown, via Flickr)
Tasty, but possibly dangerous: The US government has banned or limited lead in consumer products—like children’s jewelry or paint on toys—but toys made in other countries may not meet US safety standards. (Photo courtesy Tim Brown, via Flickr)

Is lead really a big problem?
The CDC estimates that 890,000 US children between the ages of one and five have high levels of lead in their blood. Small children put toys, fingers, and other objects in their mouths—and expose themselves to lead paint and dust if there’s any present. Lead is invisible and has no smell. And most children with elevated blood lead levels have no symptoms. The only way to tell if a child has been exposed is to have his or her blood tested. Small amounts of lead can cause brain and nervous system damage, slowed growth, or hearing problems. Larger amounts can cause kidney damage, coma, or even death.

Caregivers should be especially careful of toys made in other countries and imported into the US, and antique toys and collectibles passed down through generations.

A bigger worry: Despite all the hype over lead-contaminated toys, lead dust is a bigger risk for kids. Before 1978, lead-based paint was used in many homes. When the paint is disturbed—through daily wear-and-tear or remodeling projects—lead dust gets created. And kids eat or breathe in the dust. (Photo courtesy Geekly, via Flickr)
A bigger worry: Despite all the hype over lead-contaminated toys, lead dust is a bigger risk for kids. Before 1978, lead-based paint was used in many homes. When the paint is disturbed—through daily wear-and-tear or remodeling projects—lead dust gets created. And kids eat or breathe in the dust. (Photo courtesy Geekly, via Flickr)

What can you do?

  • The Consumer Protection Safety Council encourages frequent checks for toy recalls. Parents should immediately dispose of recalled toys. (Photos and descriptions of recalled toys can be found at http://www.cpsc.gov or call 1-800-638-2772.)
  • Just dispose of suspect toys. Only a certified laboratory can accurately test a toy for lead. Do-it-yourself kits are available, but they don’t indicate how much lead is present and their reliability at detecting low levels of lead hasn’t been determined. Don't donate recalled toys or put them out at the curb; destroy them instead.
  • Wash your child’s hands frequently to help reduce exposure.
Oct
02
2007

Alzheimer's disease, often called "old timers disease" effects about 1 in 5 people over age 80. Called dementia, the symptoms include problems with memory, thinking, behavior, and emotion.

Alzheimer's similar to diabetes

Researchers at Northwestern University think that the mechanism of Alzheimer's involves insulin receptors in brain cells. In the brain, insulin and insulin receptors are vital to learning and memory.

A toxic protein found in the brains of individuals with Alzheimer's removes insulin receptors from nerve cells, rendering those neurons insulin resistant.
The protein, known to attack memory-forming synapses, is called an ADDL for "amyloid ß-derived diffusible ligand." Science Daily

William L. Klein, professor of neurobiology and physiology in the Weinberg College of Arts and Sciences, said he believes the findings are a major factor in the memory deficiencies caused by ADDLs in Alzheimer's brains and reveals a fundamental new connection between diabetes and Alzheimer's disease. This offers hope for therapeutics. Finding ways to make those insulin receptors themselves resistant to the impact of ADDLs. might not be so difficult.

Early detection of Alzheimer's Disease

Klein not only helped identify the bio-marker, ADDL, but also helped develop a technique to detect it in patients with early stage Alzheimer's using bio-bar-code amplification technology.

To detect ADDLs, a magnetic microparticle and a gold nanoparticle are each outfitted with an antibody specific to the ADDL antigen. When in solution, the antibodies “recognize” and bind to the ADDL, sandwiching the protein between the two particles. Fienberg School of Medicine

After the “particle-ADDL-particle” sandwich is removed magnetically from solution, the bar-code DNA is removed from the sandwich and read using standard DNA detection methodologies. The researchers next would like to develop the technology so that the test could be done using a blood or urine sample instead of cerebrospinal fluid, which is more difficult to obtain.

Sep
30
2007

Drowning his sorrows: Sorry, little buddy, but it won't work.  (Photo courtesy of AlexK100 on flickr.com)
Drowning his sorrows: Sorry, little buddy, but it won't work. (Photo courtesy of AlexK100 on flickr.com)
Scientists are giving alcohol to little ratsies and discovering that drinking may, in fact, strengthen memory. At first glance, this flies in the face of hundreds of years of college students waking up with skinned knees, burned fingers, and mystery bruises, and then wondering how they possibly could have obtained them, but the methods employed by Ohio State researchers are hilarious enough, in a casual cruelty kind of way, that one has to take notice.

The researchers found that moderate consumption of alcohol seems to benefit memory, while the consumption of large amounts tends to impair it, except in situations involving “heightened emotion.”

These conclusions were reached by giving rats liquid food solutions containing 0, 2.5, or 5 percent alcohol. According to their report, “the lower dose of alcohol is equivalent to a couple of glasses of wine a day and produces blood-alcohol levels well below typical legal driving limits. The higher dose gave the rats equivalent blood-alcohol levels well above the driving limits.”

I wasn’t aware rats were even legally able to drive in the first place, but, then again, I’ve never been to Ohio.

The moderate drinking rats were found to have improved “neutral” memory (like the ability to recall the location of objects), as well as “emotional” memory (the emotional incident apparently being an electric shock to the foot). The heavy drinking rats were less able to remember the location of objects, but recalled the emotional memory (electrocution) very well.

The researchers think that the benefit of moderate drinking may be from the brain sensing the alcohol as a mild injury, and becoming stronger as a response – sort of like physical exercise, where muscles are challenged and then strengthen.

Apparently the idea of “drinking to forget” only works if you’re a very committed drinker, and even then you probably won’t forget your divorce. Finding your keys will be more difficult, though.

This all, of course, leaves the rats in something of a bind. With self-medication out of the picture, one wonders how they’re supposed to deal with the boozy food, as well as the constant electrocutions and memory tests. Talk therapy might be less than adequate.

Sep
25
2007

Blood test for detecting lung cancer

Lung cancer is a killer
Lung cancer is a killer
A simple blood test that identifies early lung cancer before it has had a chance to spread could save lives by alerting doctors to the need for treatment. Lung cancer is responsible for 1.3 million deaths each year worldwide. Detecting lung tumors in the earliest stages now looks promising.

HAAH protein is an indicator

Mark Semenuk, a researcher at Panacea Pharmaceuticals in Gaithersburg, Maryland, US, presented the lung cancer test at a meeting in Atlanta, Georgia, US, on molecular diagnostics in cancer therapeutic development run by the American Association for Cancer Research. Semenuk and colleagues developed the test, which measures levels of a protein called human aspartyl beta-hydroxylase (HAAH) in the blood.

Scientists believe HAAH migrates to the surface of a cell to help make it receptive to chemical cues that promote growth. Laboratory findings also suggest that if the protein stays too long at the cell's surface, it may fail to mature properly, and can become cancerous.

The test received approval for limited laboratory testing in July 2007, but the FDA has yet to approve a commercial version of the test.

In one experiment, they used this test to screen blood serum taken from 303 people, 160 of whom were known to have lung cancer at various stages of development. Their test accurately identified the presence of cancer in all but one of the patients with the disease.
In a second experiment, the team screened blood from a further 60 patients with lung cancer at several known stages of development. This included 15 people with stage 1 lung cancer – the earliest stage of this illness and at which point the cancer has not yet spread. All 60 samples tested positive for cancer, indicating that the test can reliably detect the illness early on. New Scientist

.

Detection (99%), false positives (8%)

More than 3 nanograms of HAAH per milliliter of blood is considered to be abnormal. In the test, people with lung cancer had an average HAAH count of 34 ng/ml of blood. Although the HAAH levels for the rest of the group, which included 93 non-smokers and 50 smokers, were much lower, about 8 % of those without the cancer had more than 3 ng/ml, triggering a handful of false positive results.

Sep
24
2007

Graphite drawing of Velociraptor sp: Image courtesy Matt Martyniuk via Wikipedia.
Graphite drawing of Velociraptor sp: Image courtesy Matt Martyniuk via Wikipedia.
More questions submitted to one of our featured Scientists on the Spot that were off topic for them to answer, but interestingly have some current news and connections.

Velociraptors don’t have feathers, do they?

Yes, they did. According to an article in the September 21, 2007 journal Science:

Some nonavian theropod dinosaurs were at least partially covered in feathers or filamentous protofeathers. However, a complete understanding of feather distribution among theropod dinosaurs is limited because feathers are typically preserved only in lagerstätten like that of Solnhofen, Germany or Liaoning, China. Such deposits possess clear taphonomic biases toward small-bodied animals, limiting our knowledge regarding feather presence in larger members of feathered clades.

We present direct evidence of feathers in Velociraptor mongoliensis based on the presence of quill knobs on the posterior forearm. In many living birds, raised knobs along the caudal margin of the ulna reveal where the quills of the secondary feathers are anchored to the bone by follicular ligaments. Quill knobs are variably present in extant bird species and are present in only a few basal taxa such as Ichthyornis , so their absence does not necessarily indicate a lack of feathers. Their presence, however, is a direct indicator of feathers of modern aspect (e.g., feathers composed of a rachis and vanes formed by barbs).

So, the theory is currently that they did have feathers, and may have looked something like the image in this article.

While doing some velociraptor-related reading for this question I learned that September is National Velociraptor Awareness Month, co-sponsored by the The American Society for Velociraptor Attack Prevention, the North American Velociraptor Defense Association and the United Velociraptor Widows Fund.

Why are apples good for you?

This question probably comes from the old saying that, “an apple a day keeps the doctor away”. And while just eating apples won’t by itself “keep the doctor away” it does not hurt either. Apples are a fruit, and like most fruit, it contains nutrients that are good for you, and it is a low calorie snack. Apples are source of both kinds of fiber. The soluble fiber in apples helps to prevent cholesterol buildup and as a result reduces the incident of heart disease, while the insoluble fiber in apples helps cleanse and move food quickly through the digestive system. Recent research suggests that apples may reduce the risk of certain cancers, and neurodegenerative diseases as Alzheimer's and Parkinsonism.

Speaking of apples now is a perfect time to eat them as they are being harvested. Check out a local apple orchard and try out some of the hundreds of different kinds of apples out there. (My current favorite is the Honey Crisp.) You can even send in suggestions to name a new apple developed by the University of Minnesota!

Current tiger range map in relation to historic distribution: Image courtesy Save the Tiger Fund.
Current tiger range map in relation to historic distribution: Image courtesy Save the Tiger Fund.
Where are there tigers?

Sadly, tiger populations are shrinking. Back in 2006 a study of tiger habitats found that tigers reside in a 40% smaller region then they did 10 years earlier, and currently only occupy 7% of their historic habitat areas. Tigers are found in the wild on the continent of Asia, currently in the countries of India, Bangladesh, Bhutan, Myanmar, Nepal, Cambodia, China, Laos, Thailand, Malaysia, Indonesia, Vietnam and the Amur region of far eastern Siberia. You might also be able to see a tiger in your local zoo.

Three species of tigers have already become extinct: the Balinese tiger, the Javan tiger and the Caspian tiger. More information on current tiger populations can be found here.

Sep
21
2007

This won't hurt, really: The FDA recently okayed even younger kids, those ages 2 to 4, to be eliglble for receiving their annual flu shot in a new nasal mist form.
This won't hurt, really: The FDA recently okayed even younger kids, those ages 2 to 4, to be eliglble for receiving their annual flu shot in a new nasal mist form.
If you’re young and squeamish about shots, there’s good news for you this year on the flu shot front.

The U.S. Food and Drug Administration has okayed the use of a flu shot nasal spray product – FluMist – for treating kids ages 2 to 4. The product has been on the market for a few years for people ages 5-49 who are in good health and not pregnant.

Obviously, this is pretty significant news since the biggest criers during the process of receiving a flu shot are between the ages of 2 to 4. In recent testing, those receiving the nasal flu shot had a 92-percent reduction in the rate of catching the flu than those who didn’t.

Furthermore, the nasal spray will work for people who have minor illnesses. But, obviously, those suffering conditions with nasal congestion might not get the full benefits of the nasal spray.

Here are the side effects to watch out for after application on children: runny nose, headache, wheezing, vomiting muscle aches and fever. For adults, the side effects include: runny nose, headache, sore throat and cough.

The calendar is quickly turning to the best time to get your flu shot as a nasal blast or a vaccine. October and November are the best times of the year. The Center for Disease Control suggests that children receiving a flu shot for the first time receive a nasal application in October. They’ll also need a second dose one month later.

If you’ve had flu shots in the past, it’s okay to receive your flu dosage this year nasally if you meet other qualifying criteria.

Of course, most people don’t bother to be vaccinated against the flu most years. The Minneapolis Star-Tribune reports that a record amount of doses – 130 million – are available this year, but as past practices show, only a fraction of them will be used.

Only about one in five babies who should receive a flu shot get one, the report said, and nationwide last year, about 36,000 people died from health complications from getting the flu.

Sep
20
2007

Life cycle of Naegleria fowleri: Image courtesy CDC.
Life cycle of Naegleria fowleri: Image courtesy CDC.
A friend sent me this story. Apparently a single cell amoeba – Naegleria fowleri – is appearing in some warm Orlando-area fresh water lakes and has caused at least three deaths.

In humans, once Naegleria fowleri is exposed to the human brain through the nasal passages, it is almost always fatal. Naegleria fowleri can cause Primary Amoebic Meningoencephalitis, which affects the central nervous system. Symptoms exhibited by people exposed to the amoeba start out being flu like, but also can include changes to their sense of taste and smell, which are followed rapidly (within 14 days) by confusion, lack of attention, loss of balance, seizures, coma and finally death. People exposed to Naegleria fowleri are not contagious, but there is currently no successful treatment for it – almost all cases result in death.

Naegleria fowleri infections are very rare, with only 23 documented cases between 1995 and 2005. What exactly is the cause for this sudden cluster of infections is unknown. Theories suggest that a warmer than usual summer combined with lower than average rainfall resulted in increased Naegleria fowleri populations. As a result of these three cases, warnings about the amoeba have been posted at 15 area parks and lakes encouraging bathers to stay out of water warmer than 80 degrees Fahrenheit and wearing nose clips when swimming.

The CDC has on line resources for healthy swimming posted on its website.