Posts about biology

Parasite Evolved from Cnidarians (Jellyfish etc.)

This is another instance of science research providing us interesting details about the very odd ways life has evolved on earth.

Genome sequencing confirms that myxozoans, a diverse group of microscopic parasites that infect invertebrate and vertebrate hosts, are actually highly reduced cnidarians — the phylum that includes jellyfish, corals and sea anemones.

“This is a remarkable case of extreme degeneration of an animal body plan,” said Paulyn Cartwright, associate professor of ecology and evolutionary biology at the University of Kansas (KU) and principal investigator on the research project. “First, we confirmed they’re cnidarians. Now we need to investigate how they got to be that way.”

images of myxozoans parasite spores and a jellyfish

Not only has the parasitic micro jellyfish evolved a stripped-down body plan of just a few cells, but via data generated at the KU Medical Center’s Genome Sequencing Facility researchers also found the myxozoan genome was drastically simplified.

“These were 20 to 40 times smaller than average jellyfish genomes,” Cartwright said. “It’s one of the smallest animal genomes ever reported. It only has about 20 million base pairs, whereas the average Cnidarian has over 300 million. These are tiny little genomes by comparison.”

Despite its radical phasedown of the modern jellyfish’s body structure and genome over millions of years, Myxozoa has retained the essential characteristic of the jellyfish — its stinger, or “nematocyst” — along with the genes needed to make it.

“Because they’re so weird, it’s difficult to imagine they were jellyfish,” she said. “They don’t have a mouth or a gut. They have just a few cells. But then they have this complex structure that looks just like stinging cell of cnidarian. Jellyfish tentacles are loaded with them — little firing weapons.”

The findings are the stuff of scientific fascination but also could have a commercial effect. Myxozoa commonly plague commercial fish stock such as trout and salmon.

“They’re a very diverse group of parasites, and some have been well-studied because they infect fish and can wreak havoc in aquaculture of economic importance,” Cartwright said.

Continue reading

Fighting Superbugs with Superhero Bugs

As concerns over deadly antibiotic-resistant strains of ‘superbug’ bacteria grow, scientists at the Salk Institute are offering a possible solution to the problem: ‘superhero’ bacteria that live in the gut and move to other parts of the body to alleviate life-threatening side effects caused by infections.

Salk researchers reported finding a strain of microbiome Escherichia coli bacteria in mice capable of improving the animals’ tolerance to infections of the lungs and intestines by preventing wasting–a common and potentially deadly loss of muscle tissue that occurs in serious infections. If a similarly protective strain is found in humans, it could offer a new avenue for countering muscle wasting, which afflicts patients suffering from sepsis and hospital-acquired infections, many of which are now antibiotic resistant.

images of E. coli bacteria, salmonella typhimurium and burkholderia thailandensis

Salk scientists found a strain of E. coli bacteria (left) that were able to stop muscle wasting in mice infected with either Salmonella Typhimurium (center) and Burkholderia thailandensis (right). Image courtesy the Salk Institute.

“Treatments for infection have long focused on eradicating the offending microbe, but what actually kills people aren’t the bacteria themselves–it’s the collateral damage it does to the body,” says Janelle Ayres, a Salk assistant professor in the Nomis Foundation Laboratories for Immunobiology and Microbial Pathogenesis and senior researcher on the study.

“Our findings suggest that preventing the damage–in this case muscle wasting–can stave off the most life-threatening aspects of an infection,” she adds. “And by not trying the kill the pathogen, you’re not encouraging the evolution of the deadly antibiotic-resistant strains that are killing people around the world. We might be able to fight superbugs with ‘superhero’ bugs.”

Once the most powerful and revolutionary of drugs, antibiotics appear to have reached their limits, due to the ability of bacteria to rapidly evolve resistance to the medicines. The rise of antibiotic resistance presents a grave threat to people around the world, as diseases once easily controlled repel all attempts at treatment. A recent study found that up to half of the bacteria that cause infections in US hospitals after a surgery are resistant to standard antibiotics.

In the United States alone, two million people annually become infected with bacteria that are resistant to antibiotics and at least 23,000 people die each year as a direct result of these infections, according to the U.S. Centers for Disease Control.

Continue reading

Funding Sources for Independent Postdoctoral Research Projects in Biology

Here is a nice list of funding sources for independent postdoctoral research projects in biology.

Some examples:

Directory of select science and engineering scholarships and fellowships for undergraduates, graduates and faculty on our blog.

Related: Science, Engineering and Math Fellowships (2008)Proposal to Triple NSF GFRP Awards and the Size of the Awards by 33% (2007)HHMI Expands Support of Postdoctoral ScientistsNSF Graduate Research Fellow Profiles (Sergy Brin, Google co-founder)

In Many Crops Ants Can Provide Pest Protection Superior or Equal to Chemicals at a Much Lower Cost

Ants are as Effective as pesticides

The review [of over 70 studies] was conducted by Aarhus University’s Dr Joachim Offenberg, an ecologist who has studied ants for almost 20 years. It includes studies of more than 50 pest species on nine crops across eight countries in Africa, South-East Asia and Australia.

Most of the studies in Offenberg’s review are on weaver ants (Oecophylla), a tropical species which lives in trees and weaves ball-shaped nests from leaves. Because weaver ants live in their host trees’ canopy, near the flowers and fruit that need protection from pests, they are good pest controllers in tropical orchards.

All farmers need to do is collect ant nests from the wild, hang them in plastic bags among their tree crops and feed them a sugar solution while they build their new nests. Once a colony is established, farmers then connect the trees that are part of the colony with aerial ‘ant walkways’ made from string or lianas.

After that, the ants need little, except for some water in the dry season (which can be provided by hanging old plastic bottles among the trees), pruning trees that belong to different colonies so that the ants do not fight, and avoiding insecticide sprays.

The review shows that crops such as cashew and mango can be exceptionally well protected from pests by weaver ants.

One three-year study in Australia recorded cashew yields 49% higher in plots patrolled by ants compared with those protected by chemicals. Nut quality was higher too, so net income was 71% higher with ants than with chemicals.

Similar studies in Australian mango crops found that ants could produce the same yield as chemical control, but because the ants were cheaper, and fruit quality better, net income from mangoes produced with ant protection was 73% higher.

Those crops are special cases in which the ants are vastly superior. But in many other cases ants are as effective and much cheaper than chemical options. Different species of ants are suited to protecting different types of drops. Weaver ants require a canopy, other ants can protect crops without a canopy.

I hope more farmers adopt ants to help protect their crop yields.

Related: Pigs Instead of PesticidesWhy Don’t All Ant Species Replace Queens in the Colony, Since Some DoHow To Make Your Own Pesticide with Ingredients from Your KitchenAnother Bee Study Finds CCD is Likely Due to Combination of Factors Including Pesticides (2013)

Exercise Is Really Really Good for You

Nice webcast that reviews the benefits of exercise that are confirmed by medical studies.

Other than [not] smoking there are few modifiable risk factors that seem to have the huge impact on heath activity does…

150 minutes a week of moderate (walking briskly, biking, even mowing the lawn maybe) activity (30 minutes a day 5 days a week) is a decent target for a minimum amount of activity for most people. I have not bought a car since my move (2 months ago) and walk to the grocery store, library, bank, subway, restaurants which is easily 30 minutes and usually more each trip. And for further away places I am biking.

Another option is 25 minutes of vigorous activity 3 times a week and 2 days a week of weight training. Basketball is my favorite form of vigorous activity and sometimes my biking and yard work reach that mark. I like swimming (and I did swim a fair amount when I had a pool at my condo but I don’t swim now as it isn’t right downstairs from my bedroom). I like vigorous activity as I end up feeling refreshed and it serves as a noticeable form of stress release for me.

Related: Better Health Through Exercise, Not Smoking, Low Weight, Healthy Diet and Low Alcohol IntakeExamining the Scientific Basis Around Exercise and Diet ClaimsInactivity Leads to 5.3 Million Early Deaths a Year

Scientific Inquiry Leads to Using Fluoride for Healthy Teeth

This webcast, from the wonderful SciShow, explores how we discovered fluoride helps prevent tooth decay and how we then used that knowledge and finally discovered why it worked.

I love stories of how we learn for observing what is happening. We don’t always need to innovate by thinking up creative new ideas. If we are observant we can pick up anomalies and then examine the situation to find possible explanations and then experiment to see if those explanations prove true.

When working this way we often are seeing correlation and then trying to figure out which part of the correlation is an actual cause. So in this dental example, a dentist noticed his patients had bad brown stains on their teeth than others populations did.

After investigation the natural fluoridation of the water in Colorado Springs, Colorado, USA seemed like it might be an explanation (though they didn’t understand the chemistry that would cause that result). They also explored the sense that the discolored teeth were resistant to decay.

Even without knowing why it is possible to test if the conditions are the cause. Scientists discovered by reducing the level of fluoridation in the water the ugly brown stains could be eliminated (these stains took a long time to develop and didn’t develop in adults). Eventually scientists ran an experiment in Grand Rapids, Michigan and found fluoridation of the water achieved amazing results for dental health. The practice of fluoridation was then adopted widely and resulted in greatly improved dental health.

In 1901, Frederick McKay, a recent dental school graduate, opened a dental practice in Colorado Springs, Colorado. He was interested in what he saw and sought out other dentists to explore the situation with him but had little success. In 1909, he found some success when renowned dental researcher Dr. G.V. Black collaborate with him.
Dr. H. Trendley Dean, head of the Dental Hygiene Unit at the National Institute of Health built on their work when he began investigating the epidemiology of fluorosis in 1931. It wasn’t until 1945 that the Grand Rapids test started. Science can take a long time to move forward.

Only later did scientists unravel why this worked. The fluoride reacts to create a stronger enamel than if the fluoride is not present. Which results in the enamal being less easily dissolved by bacteria.
Health tip: use a dental stimudent (dental picks) or floss your teeth to maintain healthy gums and prevent tooth decay. It makes a big difference.

Related: Why does orange juice taste so bad after brushing your teeth?Microbiologist Develops Mouthwash That Targets Only Harmful Cavity Causing BacteriaUsing Nanocomposites to Improve Dental Filling PerformanceFinding a Dentist in Chiang Mai, ThailandFalse Teeth For CatsWhy Does Hair Turn Grey as We Age?

We Have Thousands of Viruses In Us All the Time

Biology and the amazing interactions within a human body are amazing. Our bodies are teeming with other life (and almost life – viruses). All these microbes have a drastic impact on our health and those impacts are not always bad.

A Virus In Your Mouth Helps Fight The Flu

Hidden inside all of us are likely thousands of viruses — maybe more. They just hang out, harmlessly. We don’t even know they’re there.

But every once in a while, one of these viral inhabitants might help us out.

Young people infected with a type of herpes virus have a better immune response to the flu vaccine than those not infected, scientists at Stanford University report Wednesday. In mice, the virus directly stops influenza itself.

We’re talking about a ubiquitous critter, called cytomegalovirus. About half of all Americans carry it. And so do nearly 100 percent of people in developing countries.

In younger people, CMV had the opposite effect that Davis had predicted: “The virus ramped up the immune system to give better protection from pathogens,” Mark Davis says. “We tested only for the flu, but I speculate it protects against everything.”

So should we all go out and get infected with CMV? No way! Davis exclaims.

You see, CMV has a dark side. It can become dangerous if the immune system is suppressed, which happens after an organ transplant or during treatments for autoimmune disorders. CMV is also a concern for pregnant woman. It’s the top viral cause of birth defects worldwide.

The human microbiome is incredible and teams with thousands of species (bacteria, viruses, members of domain Archaea, yeasts, single-celled eukaryotes, helminth parasites and bacteriophages). The complexity of interactions between all the elements of what is in our bodies and cells is one of the things that makes health care so challenging. It is also fascinating how these interactions provide benefits and costs as they work within our bodies.

The fact that we have evolved in concert with all these interactions is one of the big problems with anti-biotics. Antibiotics are miraculous when they work, but they can also decimate our natural micro-biomes which does create risks.

I would have thought Stanford wasn’t still supporting closed science :-( Sadly this research is not published in an open science manner.

Related: Foreign Cells Outnumber Human Cells in Our BodiesMicrobes Flourish In Healthy PeopleTracking the Ecosystem Within UsPeople Have More Bacterial Cells than Human CellsCats Control Rats With ParasitesSkin Bacteria

Defying Textbook Science, Study Finds Proteins Built Without DNA Instructions

Open any introductory biology textbook and one of the first things you’ll learn is that our DNA spells out the instructions for making proteins, tiny machines that do much of the work in our body’s cells. Results from a recent study show for the first time that the building blocks of a protein, called amino acids, can be assembled without blueprints – DNA and an intermediate template called messenger RNA (mRNA). A team of researchers has observed a case in which another protein specifies which amino acids are added.

“This surprising discovery reflects how incomplete our understanding of biology is,” says first author Peter Shen, Ph.D., a postdoctoral fellow in biochemistry at the University of Utah. “Nature is capable of more than we realize.”

To put the new finding into perspective, it might help to think of the cell as a well-run factory. Ribosomes are machines on a protein assembly line, linking together amino acids in an order specified by the genetic code. When something goes wrong, the ribosome can stall, and a quality control crew is summoned to the site. To clean up the mess, the ribosome is disassembled, the blueprint is discarded, and the partly made protein is recycled.

Yet this study reveals a surprising role for one member of the quality control team, a protein conserved from yeast to man named Rqc2. Before the incomplete protein is recycled, Rqc2 prompts the ribosomes to add just two amino acids (of a total of 20) – alanine and threonine – over and over, and in any order. Think of an auto assembly line that keeps going despite having lost its instructions. It picks up what it can and slaps it on.

“In this case, we have a protein playing a role similar to that filled by mRNA,” says Adam Frost, M.D., Ph.D., assistant professor at University of California, San Francisco (UCSF) and adjunct professor of biochemistry at the University of Utah. He shares senior authorship with Jonathan Weissman, Ph.D., a Howard Hughes Medical Institute investigator at UCSF, and Onn Brandman, Ph.D., at Stanford University. “I love this story because it blurs the lines of what we thought proteins could do.”

Continue reading

Virgin Births in the Animal Kingdom

Spectacular and Real Virgin Births

Scientists are discovering that virgin births occur in many different species; amphibians, reptiles, cartilaginous and bony fish and birds and it happens for reasons we don’t quite understand.

Initially, a virgin birth, also known as parthenogenesis, was thought to be triggered by extreme situations; it was only documented among captive animals, for example, perhaps by the stress, or isolation. A way to continue the bloodline when all other options had gone, when there was no other choice.

Not necessarily. It now appears that some virgin females produce offspring even in the presence of males.

Another interesting area of research for scientists. The value of sex to aid a species’ success is well understood. The value of being able to produce offspring when no males are around seems obvious also. But how this all works is quite interesting and again shows how much we have to learn.

Related: Fungus-gardening Ant Species Has Given Up Sex Completely (2010)Some Female Sharks Can Reproduce All by Themselves (2007)Amazon Molly Fish are All Female (2008)Bdelloid Rotifers Abandoned Sex 100 Million Years Ago (2007)

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
Continue reading

  • Recent Comments:

    • Douglas Sciortino: I’m still skeptical. Sure they got the board to float, but what happens when you...
    • ahmedmanoo: It’s really a wonderful picture
    • Nasiru Dauran: It was very unfortunate for missing such a great hero. I haven reading some of his...
    • Matt: I’m impressed with these innovative inventions. Glad that we still have young scientists that...
    • Burhan Nova: Wow wow wow! Fantastic idea man !
    • Stella: Very interesting. Imagine a “available tonight” in hidden ink. edit: didn’t...
    • Tanzila: It’s very essential post for us. we learn more about source of Independent Postdoctoral...
    • Ahmed: Oh i did not know that
  • Recent Trackbacks:

  • Links