Category Archives: Life Science

European Eels in Crisis After 95% Decline in Last 25 years

Eels in crisis after 95% decline in last 25 years

But the action the Environment Agency is about to take is upsetting those who rely on the eel for their livelihoods. A ban on exporting eels out of Europe – they are a popular dish in the far east – is proposed, along with a plan to severely limit the fishing season and the number of people who will be allowed licences.

It seems pretty obvious we have over-fished the oceans. Without effective regulation we will destroy the future of both the wildlife and our food source.

The eel remains one of the world’s most mysterious creatures. It is generally accepted that European eels – Anguilla anguilla – are born in the Sargasso Sea near Bermuda.

As leaf-like larvae, they are swept by the Gulf Stream towards Europe, a journey that may take a year. When the larvae reach the continental shelf they change into “glass eels” and in the spring begin to move through estuaries and into freshwater.

The animals develop pigmentation, at which point they are known as elvers and are similar in shape to the adult eel. Elvers continue to move upstream and again change colour to become brown or yellow eels.

When the fish reach full maturity – some can live to 40 and grow to 1m long – they migrate back to the ocean. Females are reported to carry as many as 10m eggs. They return to the Sargasso Sea, spawn and die.

Antigen Shift in Influenza Viruses

Antigenic shift is the process by which at least two different strains of a virus, (or different viruses), especially influenza, combine to form a new subtype having a mixture of the surface antigens of the two original strains.

Pigs can be infected with human, avian and swine influenza viruses. Because pigs are susceptible to all three they can be a breeding ground for antigenic shift (as in the recent case of H1N1 Flu – Swine Flu) allowing viruses to mix and create a new virus.

Continue reading →

Merck and Elsevier Publish Phony Peer-Review Journal

Elsevier is one of those publishers fighting open science. They try to claim that the government publishing government funded research in an open way will tarnish science. The argument makes no sense to me. Here is another crazy action on their part: they published a “journal” funded by Merck to promote Merck products. Merck Makes Phony Peer-Review Journal:

Merck cooked up a phony, but real sounding, peer reviewed journal and published favorably looking data for its products in them. Merck paid Elsevier to publish such a tome, which neither appears in MEDLINE or has a website, according to The Scientist.
…
What’s sad is that I’m sure many a primary care physician was given literature from Merck that said, “As published in Australasian Journal of Bone and Joint Medicine, Fosamax outperforms all other medications….” Said doctor, or even the average researcher wouldn’t know that the journal is bogus. In fact, knowing that the journal is published by Elsevier gives it credibility!

As I have said the journals fighting open science should have their credibility questioned. They are putting their outdated business model above science. We should not see organizations that are focused on closing science research through deceptive publicity efforts and lobbying efforts as credible.

Influenza Pandemic Alert Raised to Level 5 (of 6)

WHO Director-General, Dr Margaret Chan, announced today that she has “decided to raise the current level of influenza pandemic alert from phase 4 to phase 5.” And she further comments:

Let me remind you. New diseases are, by definition, poorly understood. Influenza viruses are notorious for their rapid mutation and unpredictable behaviour. WHO and health authorities in affected countries will not have all the answers immediately, but we will get them.

WHO will be tracking the pandemic at the epidemiological, clinical, and virological levels. All countries should immediately activate their pandemic preparedness plans. Countries should remain on high alert for unusual outbreaks of influenza-like illness and severe pneumonia.

At this stage, effective and essential measures include heightened surveillance, early detection and treatment of cases, and infection control in all health facilities.

I have reached out to companies manufacturing antiviral drugs to assess capacity and all options for ramping up production. I have also reached out to influenza vaccine manufacturers that can contribute to the production of a pandemic vaccine.

The biggest question, right now, is this: how severe will the pandemic be, especially now at the start?

It is possible that the full clinical spectrum of this disease goes from mild illness to severe disease. We need to continue to monitor the evolution of the situation to get the specific information and data we need to answer this question.

From past experience, we also know that influenza may cause mild disease in affluent countries, but more severe disease, with higher mortality, in developing countries.

No matter what the situation is, the international community should treat this as a window of opportunity to ramp up preparedness and response.

Above all, this is an opportunity for global solidarity as we look for responses and solutions that benefit all countries, all of humanity. After all, it really is all of humanity that is under threat during a pandemic.

As I have said, we do not have all the answers right now, but we will get them.
—- end of her remarks —-
The latest WHO Epidemic and Pandemic Alert and Response release puts the total number of confirmed cases at 148, in 9 countries, with 8 deaths. Mexico has many more suspected cases but just 26 confirmed cases. The CDC Swine Influenza site, puts the total number of confirmed cases in the USA at 91, in 10 states, with 1 death.

Swine Flu: a Quick Overview

World Health Organization on Swine influenza

After reviewing available data on the current situation, Committee members identified a number of gaps in knowledge about the clinical features, epidemiology, and virology of reported cases and the appropriate responses. The Committee advised that answers to several specific questions were needed to facilitate its work.

The Committee nevertheless agreed that the current situation constitutes a public health emergency of international concern.

Based on this advice, the Director-General has determined that the current events constitute a public health emergency of international concern, under the Regulations.

Swine flu: a quick overview–and new New York and Kansas cases by Tara Smith

while the cases in the US have been mild and no deaths have occurred that we’re aware of, it seems in Mexico that young people are dying from this–a group that is typically not hard-hit by seasonal influenza viruses. Readers familiar with influenza and know the history of the 1918 influenza pandemic will recall that the “young and healthy” were disproportionally struck by that virus as well–so this knowledge is currently disconcerting and worrisome, but there are so many gaps in our information as far as what’s really going on in Mexico that it’s difficult to make heads or tails out of this data right now.

Third, is this really a new virus? So few influenza isolates are actually analyzed each year (in proportion to the number of people infected) that we aren’t sure yet whether this is something brand-new, or something that has been circulating at a low level for awhile, but just hadn’t been picked up. After all, H1N1 is a common serotype, so additional molecular testing is needed to determine that it’s “swine flu” versus “human” H1N1.
…
this is a fast-developing story, and it will take much more investigation and field work to determine the true extent of the virus’s spread in the population; to figure out… how efficiently it’s transmitted…

This is very early in the scientific inquiry process looking into what exactly is going on. It is too early to tell how serious a threat this is. The reaction of WHO, CDC though shows they are taking the threat seriously. By far the biggest danger in such situations, is reacting too slowly to serious and contagious threats. If you wait to react until proof exists that the situation is very serious the situation can be almost impossible to control. So you need to react quickly to shut down the spread of the threat, hopefully before it has spread too far.

Iron-breathing Species Isolated in Antarctic for Millions of Years

Graphic showing environment of Antarctic subglacial microbes

Graphic of Blood Falls showing microbial community environment in the Antarctic by Zina Deretsky at NSF)

A reservoir of briny liquid buried deep beneath an Antarctic glacier supports hardy microbes that have lived in isolation for millions of years, researchers report this week. The discovery of life in a place where cold, darkness, and lack of oxygen would previously have led scientists to believe nothing could survive comes from a team led by researchers at Harvard University and Dartmouth College.

Despite their profound isolation, the microbes are remarkably similar to species found in modern marine environments, suggesting that the organisms now under the glacier are the remnants of a larger population that once occupied an open fjord or sea.

“It’s a bit like finding a forest that nobody has seen for 1.5 million years,” says Ann Pearson, Thomas D. Cabot Associate Professor of Earth and Planetary Sciences in Harvard’s Faculty of Arts and Sciences. “Intriguingly, the species living there are similar to contemporary organisms, and yet quite different — a result, no doubt, of having lived in such an inhospitable environment for so long.”

“This briny pond is a unique sort of time capsule from a period in Earth’s history,” says lead author Jill Mikucki, now a research associate in the Department of Earth Sciences at Dartmouth and visiting fellow at Dartmouth’s Dickey Center for International Understanding and its Institute of Arctic Studies. “I don’t know of any other environment quite like this on Earth.”

Chemical analysis of effluent from the inaccessible subglacial pool suggests that its inhabitants have eked out a living by breathing iron leached from bedrock with the help of a sulfur catalyst. Lacking any light to support photosynthesis, the microbes have presumably survived by feeding on the organic matter trapped with them when the massive Taylor Glacier sealed off their habitat an estimated 1.5 to 2 million years ago.
Continue reading →

Nanoparticles With Scorpion Venom Slow Cancer Spread

In a, chlorotoxin molecules, colored blue and green, attach themselves to a central nanoparticle. In b, each nanoprobe offers many chlorotoxin molecules that can simultaneously latch on to many MMP-2s, depicted here in yellow, which are thought to help tumor cells travel through the body. In c, over time nanoprobes draw more and more of the MMP-2 surface proteins into the cell, slowing the tumor’s spread. Image from the University of Washington.

University of Washington researchers found they could cut the spread of cancerous cells by 98 percent, compared to 45 percent for the scorpion venom alone, by combining nanoparticles with a scorpion venom compound already being investigated for treating brain cancer.

For more than a decade scientists have looked at using chlorotoxin, a small peptide isolated from scorpion venom, to target and treat cancer cells. Chlorotoxin binds to a surface protein overexpressed by many types of tumors, including brain cancer. Previous research by Miqin Zhang‘s group combined chlorotoxin with nanometer-scale particles of iron oxide, which fluoresce at that size, for both magnetic resonance and optical imaging.

Chlorotoxin also disrupts the spread of invasive tumors — specifically, it slows cell invasion, the ability of the cancerous cell to penetrate the protective matrix surrounding the cell and travel to a different area of the body to start a new cancer. The MMP-2 on the cell’s surface, which is the binding site for chlorotoxin, is hyperactive in highly invasive tumors such as brain cancer. Researchers believe MMP-2 helps the cancerous cell break through the protective matrix to invade new regions of the body. But when chlorotoxin binds to MMP-2, both get drawn into the cancerous cell.

Research showed that the cells containing nanoparticles plus chlorotoxin were unable to elongate, whereas cells containing only nanoparticles or only chlorotoxin could stretch out. This suggests that the nanoparticle-plus-chlorotoxin disabled the machinery on the cell’s surface that allows cells to change shape, yet another step required for a tumor cell to slip through the body.

So far most cancer research has combined nanoparticles either with chemotherapy that kills cancer cells, or therapy seeking to disrupt the genetic activity of a cancerous cell. This is the first time that nanoparticles have been combined with a therapy that physically stops cancer’s spread.

Full press release

Amazonian Ant Species is All Female, Reproduces By Cloning

Ants inhabit ‘world without sex’

The ants reproduce via cloning – the queen ants copy themselves to produce genetically identical daughters. This species – the first ever to be shown to reproduce entirely without sex – cultivates a garden of fungus, which also reproduces asexually.
…
Dr Himler’s interest in Mycocepurus smithii was originally sparked not by their unusually biased sex ratio, but by their ability to cultivate crops. “Ants discovered farming long before we did – they have been cultivating fungus gardens for an estimated 80 million years.

“They collect plant material, insect faeces and even dead insects from the forest floor and feed it to their crops,” she said.

Bacteria Communicate Using a Chemical Language

Each person has about 1 trillion human cells and about 10 trillion bacterial cells. In the webcast Bonnie Bassler, Department of Molecular Biology at Princeton University, discusses the chemical language that lets bacteria coordinate defense and mount attacks (quorum sensing). The find has stunning implications for medicine, industry — and our understanding of ourselves.

Bacteria do all sorts of amazing things for us: educating your immune system to keep bad microbes out, they digest our food, they make our vitamins…

E.O. Wilson: Lord of the Ants

This is a great webcast on E.O Wilson‘s career studying ants and animal behavior from NOVA.

Not only is the scientific knowledge very interesting it again shows that challenging conventional wisdom, while part of the scientific method, does not mean it is an easy process for those pioneers. From his web site:

In 1971 Wilson published his second major synthesis, The Insect Societies, which formulated the existing knowledge of the behavior of ants, social bees, social wasps, and termites, on a foundation of population biology. In it he introduced the concept of a new discipline of sociobiology, the systematic study of the biological basis of social behavior in all kinds of organisms. In 1975 he published Sociobiology: The New Synthesis, which extended the subject to vertebrates and united it more closely to evolutionary biology. The foundational discoveries of sociobiology are generally recognized to be the analysis of animal communication and division of labor, in which Wilson played a principal role, and the genetic theory of the origin of social behavior, which he helped to promote and apply in his 1971 and 1975 syntheses. Sociobiology: The New Synthesis was later ranked in a poll of the officers and fellows of the international Animal Behaviour Society as the most important book on animal behavior of all time, and is regarded today as the founding text of sociobiology and its offshoot, evolutionary psychology.

Related: Journey to the Ants: A Story of Scientific Exploration
by Bert HÃ¶lldobler and Edward O. Wilson – Huge Ant Nest – Symbiotic relationship between ants and bacteria – Royal Ant Genes – posts on ants – Encyclopedia of Life