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Lots of Bacteria are Always Living in Our Bodies

My response to a question on Reddit – Ask Science:

Let’s say you get infected with a bacterium that causes annoying, but totally non-dangerous symptoms. If you just try to “live with it,” will your immune system eventually kill it, or does killing bacteria require antibiotics in all cases?

Your body definitely kills lots of bacteria.

Your body also has tons of bacteria all the time (many doing much more good than they do harm). These bacteria also compete with each other.

So your “existing” bacteria kill off others all the time too (you have lots of different types of bacteria full time in your body – they often settle into niches and fight off any others , which is normally good as they are long term residents your body has learned to live with them).

Also like everything bacteria die off themselves – though if the conditions are right they are multiplying like crazy so that exceeds die off.

An astonishing number and variety of microbes, including as many as 400 species of bacteria, help humans digest food, mitigate disease, regulate fat storage, and even promote the formation of blood vessels.

According to estimates, phages destroy up to 40 percent of the bacteria in Earth’s oceans each day.

Staphylococcal food poisoning – an example of bacteria infection my body dealt with quickly.

People talk about genetics impact on getting cavities and impact of brushing and flossing well. Also the makeup of bacteria can help or hurt. If your mouth is home to certain bacteria tooth decay is less likely, home to others it is more likely. They tend to remain fairly steady (a certain makeup of bacteria will be consist for a person over the long term – not perfectly that way but tend that way). A UCLA microbiologist developed a mouthwash to try and ceed your mouth with good bacteria and oust the bad guys.

Related: People Have More Bacterial Cells than Human CellsHuman Gene Origins: 37% Bacterial, 35% Animal, 28% Eukaryotic

Epigenetics, Scientific Inquiry and Uncertainty

Science is full of fascinating ideas. Epigenetics is one area I find particularly interesting. This previous post has a few links to learning more: DNA Passed to Descendants Changed by Your Life.

Angela Saini is one 109 people I follow on Twitter. I don’t see the point in “following” people on Twitter that you have no interest in, I only follow the small number of people that post Tweets I want to read.

In, Epigenetics: genes, environment and the generation game, Angela Saini looks at the confused state of current scientific understand now. It is very difficult to tell if, and if so, to what extent, epigenetic inheritance happens in people.

Professor Azim Surani, a leading developmental biologist and geneticist at the University of Cambridge, adds that while there is good evidence that epigenetic inheritance happens in plants and worms, mammals have very different biology. Surani’s lab carried out thorough studies on how epigenetic information was erased in developing mouse embryos and found that “surprisingly little gets through” the reprogramming process.

Professor Timothy Bestor, a geneticist at Columbia University in New York, is far more damning, claiming that the entire field has been grossly overhyped. “It’s an extremely fashionable topic right now. It’s very easy to get studies on transgenerational epigenetic inheritance published,” he says, adding that all this excitement has lowered critical standards.

Related: Epigenetic Effects on DNA from Living Conditions in Childhood Persist Well Into Middle AgeMedical Study Findings too Often Fail to Provide Us Useful KnowledgeScientific Inquiry Process Finds That Komodo Dragons Don’t have a Toxic Bite After All

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Lactic Acid Bacteria in Bees Counteracted Antibiotic-Resistant MRSA in Lab Experiments

13 lactic acid bacteria found in the honey stomach of bees have shown promising results as an antibiotic treatment in a series of studies at Lund University in Sweden (Open access paper: Lactic acid bacterial symbionts in honeybees – an unknown key to honey’s antimicrobial and therapeutic activities). The group of bacteria counteracted antibiotic-resistant MRSA in lab experiments. The bacteria, mixed into honey, has healed horses with persistent wounds. The formula has also previously been shown to protect against bee colony collapse.

photo of a bee on a flower

Photo by Justin Hunter

Raw honey has been used against infections for millennia, before honey – as we now know it – was manufactured and sold in stores. So what is the key to its’ antimicrobial properties? Researchers at Lund University in Sweden have identified a unique group of 13 lactic acid bacteria found in fresh honey, from the honey stomach of bees. The bacteria produce a myriad of active antimicrobial compounds.

These lactic acid bacteria have now been tested on severe human wound pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and vancomycin-resistant Enterococcus (VRE), among others. When the lactic acid bacteria were applied to the pathogens in the laboratory, it counteracted all of them.

While the effect on human bacteria has only been tested in a lab environment thus far, the lactic acid bacteria has been applied directly to horses with persistent wounds. The LAB was mixed with honey and applied to ten horses; where the owners had tried several other methods to no avail. All of the horses’ wounds were healed by the mixture.

The researchers believe the secret to the strong results lie in the broad spectrum of active substances involved.

“Antibiotics are mostly one active substance, effective against only a narrow spectrum of bacteria. When used alive, these 13 lactic acid bacteria produce the right kind of antimicrobial compounds as needed, depending on the threat. It seems to have worked well for millions of years of protecting bees’ health and honey against other harmful microorganisms. However, since store-bought honey doesn’t contain the living lactic acid bacteria, many of its unique properties have been lost in recent times”, explains Tobias Olofsson.

This is a very cool: “When used alive, these 13 lactic acid bacteria produce the right kind of antimicrobial compounds as needed, depending on the threat.” As is the note that store bought honey doesn’t contain the living bacteria. My guess is some honey bought directly from farmers or bee-keepers, at farmer’s markets may well still have those live bacteria – but I am just guessing I may be wrong.

The next step is further studies to investigate wider clinical use against topical human infections as well as on animals.

The findings have implications for developing countries, where fresh honey is easily available, but also for Western countries where antibiotic resistance is seriously increasing.

Related: People are Superorganisms With Microbiomes of Thousands of SpeciesThe Search for Antibiotic Solutions Continues: Killing Sleeper Bacteria CellsOur Dangerous Antibiotic Practices Carry Great RisksPotential Antibiotic Alternative to Treat Infection Without Resistance
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The Feynman Lectures on Physics Available Online

The Feynman Lectures on Physics are now available to read online. They are a great collection of lectures covering physics and touching on many areas including: the Mechanisms of Seeing, Semiconductors and Algebra. This is a fantastic resource for learning about physics.

You can also get a boxed set of The Feynman Lectures on Physics for those that like paper. It is fantastic but not cheap.

Bill Gates bought the rights to the rights to The Character of Physical Law, 7 lectures Feynman gave at Cornell University (these are separate from the lectures listed above) and made them available online, which is great. Unfortunately the website is based on Microsoft tools and therefore quite a bother for many (or maybe even impossible with Linux computers – I am not sure). I guess since he made all his money via Microsoft it isn’t that surprising but it would have been nice if he provide the content in a more easily accessible way (even if they didn’t do the fancy additions they did on the Microsoft site. These are great enough videos to probably be worth the bother of installing proprietary Microsoft software in order to view them.

Related: Video of Young Richard Feynman Talking About Scientific ThinkingFeynman “is a second Dirac, only this time human” (Oppenheimer) – Classic Feynman: All the Adventures of a Curious Character

Why do Bats Transmit so Many Diseases like Ebola?

Bats are generally wonderful creatures and helpful to us. For example, they eat lots of insects that are annoying (like mosquitoes) and pollinate lots of plants. Of course, they also eat lots of good (for us humans) insects but the insects still seem to be able to fulfill their environmental niches so all is good.

And they are flying mammals which is, of course, cool.

But bats also transmit virus to us, which do us lots of damage. As the video explains as we have intruded into bat territory and chopped down their natural feeding spots we have come into contact with them more. And because bats evolved to be very resilient to virus and they live in large colonies (for easy transmission of the viruses to lots of bats) they can host viruses and survive long enough to infect lots of other bats, and to infect us if we meet them.

I actually didn’t know this (mentioned in the video): most viruses have a very difficult time surviving even with temperatures a bit above the normal human temperature (98 degrees Fahrenheit). Bats, while they fly, have internal temperatures that soar to 104 degrees (40 degrees centigrade) which kills off most viruses, but certain hardy viruses survive. This also explains why we run fevers when we are sick (which then can kill off viruses) – which I am sure I learned at some point but I forgot. But for the bat viruses that strategy doesn’t work.

Bats, of course, are not impervious to disease. In the USA a disease has killed more than 90 percent of the cave bats in Eastern states.

One of the causes of the current ebola outbreak is believed to be people eating bats in West Africa.

Related: Ebola Outbreak in Uganda (2007)A Breakthrough Cure for Ebola (2010)Swine Flu: a Quick Overview (2009)

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Crows can Perform as Well as 7 to 10-year-olds on cause-and-effect Water Displacement Tasks

In Aesop’s fable about the crow and the pitcher, a thirsty bird happens upon a vessel of water, but when he tries to drink from it, he finds the water level out of his reach. Not strong enough to knock over the pitcher, the bird drops pebbles into it — one at a time — until the water level rises enough for him to drink his fill.

Highlighting the value of ingenuity, the fable demonstrates that cognitive ability can often be more effective than brute force. It also characterizes crows as pretty resourceful problem solvers. New research conducted by UC Santa Barbara’s Corina Logan, with her collaborators at the University of Auckland in New Zealand, proves the birds’ intellectual prowess may be more fact than fiction. Her findings, supported by the National Geographic Society/Waitt Grants Program, appear today in the scientific journal PLOS ONE: Modifications to the Aesop’s Fable Paradigm Change New Caledonian Crow Performances.

photo of Corina Logan

Researcher Corina Logan with a great-tailed grackle and a night heron at the Santa Barbara Zoo. The zoo is one of the sites where Logan is gathering data to compare and contrast the cognitive abilities of grackles and New Caledonian crows.
Photo Credit: Sonia Fernandez

Logan is lead author of the paper, which examines causal cognition using a water displacement paradigm. “We showed that crows can discriminate between different volumes of water and that they can pass a modified test that so far only 7- to 10-year-old children have been able to complete successfully. We provide the strongest evidence so far that the birds attend to cause-and-effect relationships by choosing options that displace more water.”

Logan, a junior research fellow at UCSB’s SAGE Center for the Study of the Mind, worked with New Caledonian crows in a set of small aviaries in New Caledonia run by the University of Auckland. “We caught the crows in the wild and brought them into the aviaries, where they habituated in about five days,” she said. Keeping families together, they housed the birds in separate areas of the aviaries for three to five months before releasing them back to the wild.

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Looking Inside Living Cells

Johns Hopkins’ molecular biologist Jin Zhang explains how she uses light to see where and when within cells specific molecular processes occur and what happens when they go wrong.

Related: How Lysozyme Protein in Our Tear-Drops Kill BacteriaScience Explained: How Cells React to Invading VirusesNobel Prize in Physiology or Medicine 2012 for Reprogramming Cells to be PluripotentWebcast Exploring Eukaryotic Cells

Starting a Career in Science to Fight Cancer

Keven Stonewall Preventing Colon Cancer from VNM USA on Vimeo.

Keven Stonewall is a student at the University of Wisconsin – Madison working to prevent colon cancer.

Related: I Always Wanted to be Some Sort of ScientistHigh School Student Creates Test That is Much More Accurate and 26,000 Times Cheaper Than Existing Pancreatic Cancer TestsWebcast of a T-cell Killing a Cancerous Cell

A Healthy Lifestyle is More About Health Care than the Sickness Management That We Call Health Care Is

American Heart Association Recommendations for Physical Activity in Adults

Being physically active is important to prevent heart disease and stroke, the nation’s No. 1 and No. 4 killers. To improve overall cardiovascular health, we suggest at least 150 minutes per week of moderate exercise or 75 minutes per week of vigorous exercise (or a combination of moderate and vigorous activity). Thirty minutes a day, five times a week is an easy goal to remember. You will also experience benefits even if you divide your time into two or three segments of 10 to 15 minutes per day.

For people who would benefit from lowering their blood pressure or cholesterol, we recommend 40 minutes of aerobic exercise of moderate to vigorous intensity three to four times a week to lower the risk for heart attack and stroke.

The simplest, positive change you can make to effectively improve your heart health is to start walking. It’s enjoyable, free, easy, social and great exercise. A walking program is flexible and boasts high success rates because people can stick with it.

It really is important for giving yourself the best chance for health by taking sensible steps to exercise based on your own situation (obviously some health conditions may limit your ability to exercise safely, which is something each person has to judge and see a doctor about if necessary).

Doing small things like using a treadmill while you watch TV or taking the stairs instead of the elevator for short trips can help. Another option is to walk instead of driving your car, or if you drive parking a few blocks away (or at the far side of the parking lot) walking, or if you are running several errands walk between those that you can even if you are using your car. Biking to work is another healthy lifestyle choice (if you city has made this safe – too often they fail to do sensible things).

photo of a forest

Forest hike on Hole in the Wall trail, Olympic National Park, Oregon, USA by John Hunter

Swimming is good exercise and something I took up several years ago (I was super lame at first but within a month or two it was better. I love hiking through national parks. A standing desk (or treadmill desk) is another option to reduce the damage of our sedentary lives.

Another thing to remember is losing weight is hard. It is better to avoid gaining too much weight in the first place. Avoiding the weight gain may also be a challenge but it is better than the alternative.

Too often we treat “health care” as sickness management. Doing things like creating a healthy lifestyle are are health care. Taking pills and antibiotics is mainly about sickness management.

Related: Better Health Through Exercise, Not Smoking, Low Weight, Healthy Diet and Low Alcohol IntakePhysical Activity for Adults: Inactivity Leads to 5.3 Million Early Deaths a YearHealthy Diet, Healthy Living, Healthy WeightStudy Finds Obesity as Teen as Deadly as Smoking

Massive Blast of Measles Vaccine Wiped Out Cancer In Study

Unfortunately these stories are not uncommon but the hoped for follow through of practical solutions that work at all are rare. But we keep learning and while the breakthroughs based on these news stories is rare we do keep finding new and better methods to cope with health issues.

Mayo Clinic trial: Massive blast of measles vaccine wipes out cancer

Stacy Erholtz was out of conventional treatment options for blood cancer last June when she underwent an experimental trial at the Mayo Clinic that injected her with enough measles vaccine to inoculate 10 million people.

The 50-year-old Pequot Lakes mother is now part of medical history.

The cancer, which had spread widely through her body, went into complete remission and was undetectable in Erholtz’s body after just one dose of the measles vaccine, which has an uncanny affinity for certain kinds of tumors.

Erholtz was one of just two subjects in the experiment and the only one to achieve complete remission. But the experiment provides the “proof of concept” that a single, massive dose of intravenous viral therapy can kill cancer by overwhelming its natural defenses, according to Dr. Stephen Russell, a professor of molecular medicine who spearheaded the research at Mayo.

Researchers have known for decades that viruses can be used to destroy cancer. They bind to tumors and use them as hosts to replicate their own genetic material; the cancer cells eventually explode and release the virus. Antiviral vaccines that have been rendered safe can produce the same effects and can also be modified to carry radioactive molecules to help destroy cancer cells without causing widespread damage to healthy cells around the tumors. The body’s immune system then attacks any remaining cancer that carries remnants of the vaccine’s genetic imprint.

Mayo started out giving patients 1 million infectious units and gradually cranked up the dosage — but it didn’t work until Erholtz and another patient were injected with 100 billion infectious units, he said.

While the treatment worked in Erholtz, whose tumors were primarily in her bone marrow, the results weren’t sustained in the second patient, whose tumors were largely confined to her leg muscles. Russell said researchers need to study how the nature of the tumor affects the lethality of the virus.

One challenge of health research on fatal health conditions is that the experimentation with people is usually limited to people that have no available options left from the approved treatments. So, in general they are very sick. And the great complexity of dealing with human immune systems, the variation in the disease and in people create a very difficult research environment. Thankfully we have many great scientists dedicated to finding new treatments.

Related: Virus Kills Breast Cancer Cells in LaboratoryVirus Engineered To Kill Deadly Brain TumorsUsing Bacteria to Carry Nanoparticles Into CellsWebcast of a T-cell Killing a Cancerous Cell

Science Explained: How Cells React to Invading Viruses

This illustrated webcast introduces the microscopic arsenal of weapons and warriors that play a role in the battle for your health.

TED education has been putting out some good videos which is a wonderful thing to see. It is wonderful to let people everywhere (kids and adults) that are interested in learning (and that have internet access) can learn about the world around us. Traditional educational institutions have not done much with this opportunity to broaden their impact.

The video looks at the cells reaction to a virus infiltrating the cell.

Related: Cells AliveScience Explained: Cool Video of ATP Synthase, Which Provides Usable Energy to UsThis webcast is packed with information on the makeup and function of eukaryotic (animal) cellsCool Animation of a Virus Invading a Person’s BodyCell Aging and Limits Due to TelomeresWebcast of a T-cell Killing a Cancerous Cell

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