Posts about biology

Biology: How Wounds to Our Skin Heal

This is an interesting webcast looking at how our bodies heal wounds to our skin.

Related: Science Explained: How Cells React to Invading VirusesTissue Regeneration in AnimalsScience Explained: Cool Video of ATP Synthase, Which Provides Usable Energy to UsLooking Inside Living CellsA Healthy Lifestyle is More About Health Care than the Sickness Management That We Call Health Care Is

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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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

Open Source Seeds

I find the current status of government granted patents to be very flawed, including patenting life.

Plant Breeders Release First ‘Open Source Seeds’

A group of scientists and food activists is launching a campaign Thursday to change the rules that govern seeds. They’re releasing 29 new varieties of crops under a new “open source pledge” that’s intended to safeguard the ability of farmers, gardeners and plant breeders to share those seeds freely.

Irwin Goldman, a vegetable breeder at the University of Wisconsin, Madison, helped organize the campaign. It’s an attempt to restore the practice of open sharing that was the rule among plant breeders when he entered the profession more than 20 years ago.

Good for them. This needs to be supported. The crazy practices of seed companies shouldn’t be legal but they pay lots of cash to politicians and the corrupt politicians (which seems to be an awful lot of them) write bad policy and encourage bad regulation.

Even those administrators taking control of universities have subjugated the search for knowledge and improvement to seek monetary gain instead of what the universities used to prioritize. It is a shame and those that have distorted universities so much should be ashamed.

Initial efforts that lead to the bad place we find universities in now were to promote the adoption of university research. To do so they partnered with business in sensible ways. Then administrators saw money was being made and turned the priority into making money and if that meant restricting the benefits to society of university research so be it. This has created universities that have lost ethical foundations and have destroyed a big part of the value universities used to provide society.

Related: Open-Source Biotech (2006)Scientists Say Biotechnology Seed Companies Prevent Research (2009)The A to Z Guide to Political Interference in ScienceArduino: Open Source Programmable HardwareMoney Is Corrupting Our Political Process

Goats Excel at Learning and Remembering a Complex Tasks

I like research showing animals using intelligence that seems advanced, for example: Crow Using a Sequence of Three ToolsInsightful Problem Solving in an Asian ElephantBird-brains smarter than your average apeTropical Lizards Can Solve Novel Problems and Remember the SolutionsPigeon Solves Box and Banana Problem.

I also like open access science, and this has both: Goats excel at learning and remembering a highly novel cognitive task

The majority of trained goats (9/12) successfully learned the task quickly; on average, within 12 trials. After intervals of up to 10 months, they solved the task within two minutes, indicating excellent long-term memory. The goats did not learn the task faster after observing a demonstrator than if they did not have that opportunity. This indicates that they learned through individual rather than social learning.”

The individual learning abilities and long-term memory of goats highlighted in our study suggest that domestication has not affected goat physical cognition. However, these cognitive abilities contrast with the apparent lack of social learning, suggesting that relatively intelligent species do not always preferentially learn socially. We propose that goat cognition, and maybe more generally ungulate cognition, is mainly driven by the need to forage efficiently in harsh environments and feed on plants that are difficult to access and to process, more than by the computational demands of sociality. Our results could also explain why goats are so successful at colonizing new environments.

The experiment was done with domesticated goats. I also learned this from the article, which I didn’t know before:

Domestication is known to strongly affect brain size. Consistent reductions in brain size relative to body size, as well as in brain size parts, have occurred in many domestic species.

Related: Orangutan Attempts to Hunt Fish with SpearFriday Fun: Bird Using Bait to FishPhoto of Fish Using a Rock to Open a Clam

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Refusal to Follow Scientific Guidance Results in Worms Evolving to Eat Corn Designed to Kill The Worms

An understanding of natural selection and evolution is fundamental to understanding science, biology, human health and life. Scientists create wonderful products to improve our lives: vaccines, antibiotics, etc.; if we don’t use them or misuse them it is a great loss to society.

There is also great value in genetic enhanced seeds and thus plants (through natural human aided processes such as breeding and providing good genetic material over a wide area – distances that would not be covered naturally, at least not in a time that helps us much). Genetic Modified Organisms (GMO) food, in which we tinker with the genes directly also holds great promise but has risks, especially if we forget basic scientific principles such as biodiversity.

Voracious Worm Evolves to Eat Biotech Corn Engineered to Kill It

First planted in 1996, Bt corn quickly became hugely popular among U.S. farmers. Within a few years, populations of rootworms and corn borers, another common corn pest, had plummeted across the midwest. Yields rose and farmers reduced their use of conventional insecticides that cause more ecological damage than the Bt toxin.

By the turn of the millennium, however, scientists who study the evolution of insecticide resistance were warning of imminent problems. Any rootworm that could survive Bt exposures would have a wide-open field in which to reproduce; unless the crop was carefully managed, resistance would quickly emerge.

Key to effective management, said the scientists, were refuges set aside and planted with non-Bt corn. Within these fields, rootworms would remain susceptible to the Bt toxin. By mating with any Bt-resistant worms that chanced to evolve in neighboring fields, they’d prevent resistance from building up in the gene pool.

But the scientists’ own recommendations — an advisory panel convened in 2002 by the EPA suggested that a full 50 percent of each corn farmer’s fields be devoted to these non-Bt refuges — were resisted by seed companies and eventually the EPA itself, which set voluntary refuge guidelines at between 5 and 20 percent. Many farmers didn’t even follow those recommendations.

Using extremely powerful tools like GMO requires society to have much better scientific literacy among those making decisions than any societies have shown thus far. The failure of our governments to enforce sensible scientific constraints on such use of genetic engineering creates huge risks to society. It is due to this consistent failure of our government to act within sensible scientific constraints that causes me to support efforts (along with other reasons – economic understanding – the extremely poor state of patent system, risk reduction…) to resist the widespread adoption of GMO, patenting of life (including seeds and seeds produced by seeds).

Wonderful things are possible. If we grow up and show a long term track record of being guided by scientific principles when the risks of not doing so are huge then I will be more supportive of using tactics such as GMO more easily. But I don’t see us getting their anytime soon. If anything we are much less scietifically minded and guided than we were 50 years ago: even while we bask in the glorious wonders science has brought us on a daily basis.

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More Muscle Mass Appears Linked to Longer Life

New UCLA research suggests that the more muscle mass older Americans have, the less likely they are to die prematurely. The findings add to the growing evidence that overall body composition — and not the widely used body mass index, or BMI — is a better predictor of all-cause mortality. The study was published in the in a closed science journal (it is too bad UCLA promotes such anti-science practices). The research was funded by the NIH (who also shouldn’t allow such anti-science practices).

Dr. Preethi Srikanthan: “many studies on the mortality impact of obesity focus on BMI. Our study indicates that clinicians need to be focusing on ways to improve body composition, rather than on BMI alone, when counseling older adults on preventative health behaviors.”

The researchers analyzed data collected by the National Health and Nutrition Examination Survey (NHANES) III, conducted between 1988 and 1994. They focused on a group of 3,659 individuals that included men who were 55 or older and women who were 65 or older at the time of the survey. The authors then determined how many of those individuals had died from natural causes based on a follow-up survey done in 2004.

The body composition of the study subjects was measured using bioelectrical impedance, which involves running an electrical current through the body. Muscle allows the current to pass more easily than fat does, due to muscle’s water content. In this way, the researchers could determine a muscle mass index — the amount of muscle relative to height — similar to a body mass index. They looked at how this muscle mass index was related to the risk of death.

They found that all-cause mortality was significantly lower in the fourth quartile of muscle mass index compared with the first quartile.

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Why Don’t All Ant Species Replace Queens in the Colony, Since Some Do

My response to: There are other species of ants that do replace the queen, so why did some species not do this?

Basically the method they evolved copes well with losing the queen. Out of various ways of dealing with having a dominant Queen some may lead to replacement if she dies.

There are lots of examples of method is very effective at creating lots of successful offspring but happens to be less than ideal in some situations. Natural selection is pretty amazing and awesome at creating effective genes but we certainly can look at the results sometimes and see improvements that would be useful.

Likely if losing the queen was very common a good way of dealing with that would be found (or that species would be disadvantaged and at risk). If the queen happens to evolve to being very reliable coping with her death becomes less important. If they produce lots of useful offspring but have a less than ideal method of coping with their home colony losing her it is entirely sensible to imagine that species could flourish.

I would imagine species with queens that had shorter lifespans, that invested more in the home colony, that were less effective at setting up new colonies… would be more likely to have better queen replacement strategies/results.

Related: Ants, Ants, AntsE.O. Wilson: Lord of the AntsAmazonian Ant Species is All Female, Reproduces By CloningRoyal Ant GenesHuge Ant Nest

How Our Brains React to Sugar

The dopamine reaction to sugar leads us to seek out that good feeling. Sugars can lead us astray by encouraging us to seek more than is good for us.

A sensible explanation is that sugars provide high calories and were rare and so the more we could find the better. Evolution takes a long time to adjust though (and of course misses things that don’t affect passing on successful genes) so long (in our human timeframe, short in evolutionary timeframe) after we have far too much sugar available our brains our encouraging us to eat all we can find. This of course, at best, is a very oversimplified view.

Related: Can Just A Few Minute of Exercise a Day Prevent Diabetes?Does Diet Soda Result in Weight Gain?How Caffeine Affects Your Body

DNA Contains Gene Control Instructions

Scientists discover double meaning in genetic code

Scientists have discovered a second code hiding within DNA. This second code contains information that changes how scientists read the instructions contained in DNA and interpret mutations to make sense of health and disease.

“For over 40 years we have assumed that DNA changes affecting the genetic code solely impact how proteins are made,” said Stamatoyannopoulos. “Now we know that this basic assumption about reading the human genome missed half of the picture. These new findings highlight that DNA is an incredibly powerful information storage device, which nature has fully exploited in unexpected ways.”

The genetic code uses a 64-letter alphabet called codons. The UW team discovered that some codons, which they called duons, can have two meanings, one related to protein sequence, and one related to gene control. These two meanings seem to have evolved in concert with each other. The gene control instructions appear to help stabilize certain beneficial features of proteins and how they are made.

The discovery of duons has major implications for how scientists and physicians interpret a patient’s genome and will open new doors to the diagnosis and treatment of disease.

“The fact that the genetic code can simultaneously write two kinds of information means that many DNA changes that appear to alter protein sequences may actually cause disease by disrupting gene control programs or even both mechanisms simultaneously,” said Stamatoyannopoulos.

The wonder of DNA continues to amaze.

Related: Epigenetic Effects on DNA from Living Conditions in Childhood Persist Well Into Middle AgeDNA Passed to Descendants Changed by Your LifeDNA based Algorithmic Self-Assembly

Outdoor Air Pollution Resulted in 223,000 Cancer Deaths in 2010

The specialized cancer agency of the World Health Organization, the International Agency for Research on Cancer (IARC), announced today that it has classified outdoor air pollution as carcinogenic to humans.

After thoroughly reviewing the latest available scientific literature, the world’s leading experts convened by the IARC Monographs Programme concluded that there is sufficient evidence that exposure to outdoor air pollution causes lung cancer. They also noted a positive association with an increased risk of bladder cancer.

Particulate matter, a major component of outdoor air pollution, was evaluated separately and was also classified as carcinogenic to humans.

The IARC evaluation showed an increasing risk of lung cancer with increasing levels of exposure to particulate matter and air pollution. Although the composition of air pollution and levels of exposure can vary dramatically between locations, the conclusions of the Working Group apply to all regions of the world.

Air pollution is already known to increase risks for a wide range of diseases, such as respiratory and heart diseases. Studies indicate that in recent years exposure levels have increased significantly in some parts of the world, particularly in rapidly industrializing countries with large populations. The most recent data indicate that in 2010, 223,000 deaths from lung cancer worldwide resulted from air pollution.

“The air we breathe has become polluted with a mixture of cancer-causing substances,” says Dr Kurt Straif.

The stories of amazingly high (and persistent) air pollution levels in China have been continuing for years. But, while China, likely represents several of the worst existing air pollution conditions hundreds of thousands have died outside China due to air pollution just in the last 5 years.

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