Monday, 26 May 2008

Weekly BioNews 19 - 26 May 2008

- Scientists 'paint' viruses to track their fate in the body

May 20, 2008 05:40 PM

Biologists from Austria and Singapore developed a technique that adds a new twist on the relationship between biology and art. In an article recently published online in The FASEB Journal ( and scheduled for the August 2008 print issue, these researchers describe how they were able to coat—or paint—viruses with proteins.

This breakthrough should give a much-needed boost to the efficiency of some forms of gene therapy, help track and treat viral disease and evolution, improve the efficiency of vaccines, and ultimately allow health care professionals track the movement of viral infections within the body. Specifically, the new method should make it easier to track and treat infectious diseases such as HIV/AIDS, influenza, hepatitis C, and dengue fever. And because viruses can also be used to introduce biotechnology drugs and replacement genes, and act as vaccines, this research should lead to new treatments for cancer, cardiovascular, metabolic and inherited disorders.....

- Fluorescent nano-barcodes could revolutionize diagnostics

May 22, 2008 07:31 PM

A new technology with research and clinical application including the early detection of disease has been invented and developed by University of Queensland researchers.

Dr Krassen Dimitrov, from UQ's Australian Institute for Bioengineering & Nanotechnology, has developed fluorescent “barcodes” called nanostrings, offers greater sensitivity and accuracy than current detection methods.

The research has been published the prestigious international journal Nature Biotechnology.

Dr Dimitrov said nanostrings bind to RNA molecules for digital gene expression analysis.

“Because this system can count the exact number of biomolecules present we can get an extremely accurate and sensitive picture of gene expression at a particular point in time,” Dr Dimitrov said.

“This quantitative data is superior to other gene expression systems such as microarrays, which rely on the analogue measurement of fluorescence and therefore are less accurate and have a limited range.

“The nanostring is an important technological development in both clinical and research settings. We will be able to more accurately detect molecules associated with particular diseases and in the research arena, we will be able to identify new molecules associated with diseases and trace these back to the genes responsible."

- Plant Flavonoid In Celery And Green Peppers Found To Reduce Inflammatory Response In The Brain

ScienceDaily (May 23, 2008)

Researchers at the University of Illinois report that a plant compound found in abundance in celery and green peppers can disrupt a key component of the inflammatory response in the brain. The findings have implications for research on aging and diseases such as Alzheimer's and multiple sclerosis.

Inflammation can be a blessing or a blight. It is a critical part of the body's immune response that in normal circumstances reduces injury and promotes healing. When it goes awry, however, the inflammatory response can lead to serious physical and mental problems.

Inflammation plays a key role in many neurodegenerative diseases and also is implicated in the cognitive and behavioral impairments seen in aging.

The new study looked at luteolin (LOO-tee-OH-lin), a plant flavonoid known to impede the inflammatory response in several types of cells outside the central nervous system. The purpose of the study was to determine if luteolin could also reduce inflammation the brain, said animal sciences professor and principal investigator Rodney Johnson....

- Many Paths, Few Destinations: How Stem Cells Decide What They'll Become

ScienceDaily (May 24, 2008)

How does a stem cell decide what specialized identity to adopt -- or simply to remain a stem cell? A new study suggests that the conventional view, which assumes that cells are "instructed" to progress along prescribed signaling pathways, is too simplistic. Instead, it supports the idea that cells differentiate through the collective behavior of multiple genes in a network that ultimately leads to just a few endpoints -- just as a marble on a hilltop can travel a nearly infinite number of downward paths, only to arrive in the same valley.

When exposed to a growth factor, a blood stem cell, represented by a blue marble, falls into a new "attractor state," depicted as a valley in a landscape, to become a red blood cell. Different influences, such as differentiation factors, can lead stem cells to the same attractor state, but each cell can take very different paths though the landscape to get there (just as a marble might take a different path each time it rolls down a hill). (Credit: Children's Hospital Boston)

The findings, published in the May 22 issue of Nature, give a glimpse into how that collective behavior works, and show that cell populations maintain a built-in variability that nature can harness for change under the right conditions. The findings also help explain why the process of differentiating stem cells into specific lineages in the laboratory has been highly inefficient.

Led by Sui Huang, MD, PhD, a Visiting Associate Professor in the Children's Hospital Boston Vascular Biology Program (now also on the faculty of the University of Calgary), and Hannah Chang, an MD/PhD student in Children's Vascular Biology Program, the researchers examined how blood stem cells "decide" to become white blood cell progenitors or red blood cell progenitors......

Scientists Back The Use Of Maize As An Efficient 'Factory' For Protein-based Pharmaceutical Products
ScienceDaily (May 25, 2008)
Scientists from the Universidad de Lleida (University of Lleida) have published a study supporting the argument that maize seeds are an effective and sure platform within molecular agriculture to alleviate diseases. Over the next few years AIDS could be one of the first diseases to benefit from these results, although regulations for this technology are being developed at the same time as research is being undertaken.

Maize, the third most important cereal in the world, has a great number of advantages for molecular agriculture. Among these are its physiology, its capacity to express recombinant proteins in the seeds, its widespread cultivation and its genetic diversity, as well as being anti-allergenic and non-toxic.

Last March, transgenic maize became the first plant to be developed commercially for medical use. The PNAS review published the following findings: a maize seed with genes from the 2G12 antibody (already known for its capacity to neutralise infection from the virus) could produce antibodies against the transmission of HIV. Researchers from the Departamento de Producción Vegetal y Ciencia Forestal [Department of Plant Production and Forest Science] at the Universidad de Lleida, were those who actually designed this drug during an international project known as Pharma-Planta (made up of 39 European and South African teams), and headed by the British man Paul Christou...

- Real-time Observation Of DNA-repair Mechanism

ScienceDaily (May 25, 2008)

For the first time, researchers at Delft University of Technology have witnessed the spontaneous repair of damage to DNA molecules in real time. They observed this at the level of a single DNA molecule. Insight into this type of repair mechanism is essential as errors in this process can lead to the development of cancerous cells.

Researchers from the Kavli Institute of Nanoscience Delft are to publish an article on this in the journal Molecular Cell.

Cells have mechanisms for repairing the continuous accidental damage occurring in DNA. These damages can vary from a change to a single part of the DNA to a total break in the DNA structure. These breaks can, for instance, be caused by ultraviolet light or X-rays, but also occur during cell division, when DNA molecules split and form two new DNA molecules. If this type of break is not properly repaired it can be highly dangerous to the functioning of the cell and lead to the creation of a cancerous cell.

One major DNA-repair mechanism involved in repairing these breaks is known as homologous recombination. This mechanism has been observed for the first time by Delft University of Technology researchers in real time and at the level of a single DNA molecule....

- Seasonal patterns of flu

Date: 21/05/2008

Outbreaks of the most common type of influenza virus, A (H3N2), are seeded by viruses that originate in East and Southeast Asia and migrate around the world, new research has found. This discovery may help to further improve flu vaccines and make the evolution of the virus more predictable.Scientists at the University of Cambridge, in collaboration with scientists from the World Health Organisation (WHO) Global Influenza Surveillance Network, found that each year since 2002 influenza A (H3N2) viruses have migrated out of what the authors call the 'East and Southeast Asian circulation network' (which includes tropical, subtropical, and temperate countries) and spread throughout the world. Their findings are reported in the current edition of Science.

Annual influenza epidemics are thought to infect 5 - 15 per cent of the world population each year, cause 3 to 5 million cases of severe illness, and between 250000 and 500 000 deaths, according to the WHO. The flu vaccine protects the 300 million people vaccinated each year.

Because the flu virus evolves so quickly, there are a number of challenges involved in making the vaccine.

In order to create an effective vaccine, each year in February and September a WHO committee meets to select the strains of flu to use in the influenza virus vaccine.

These scientists (many of whom are co-authors on this study) decide which strains pose the greatest threat for the next flu season.....

- Turning back the clock

Date: 19/05/2008

Myelin-making Schwann cells have an ability every ageing Hollywood star would envy: they can become young again. According to a study appearing in the May 19 issue of the Journal of Cell Biology, David B. Parkinson (University College London, London, UK) and colleagues have pinned down a protein that returns the cells to their youth, a finding that might help researchers understand why myelin production falters in some diseases.Wrapped around neurons in the peripheral nervous system, Schwann cells can "dedifferentiate" into a state in which they can't manufacture myelin. Reverting to an immature type of cell speeds healing of injured nerves. Researchers knew that the protein Krox-20 pushes immature Schwann cells to specialise and form myelin, but they didn't know what prompts the reversal. One suspect was a protein called c-Jun, which youthful Schwann cells make but Krox-20 blocks.

Parkinson et al. cultured neurons with Schwann cells whose c-Jun gene they could activate. Turning on the gene curbed myelination, suggesting that c-Jun prevents young Schwann cells from growing up. c-Jun also prodded mature Schwann cells to become youthful again, the researchers discovered. Schwann cells that are separated from neurons normally dedifferentiate, but the team found that the cells remained specialised if c-Jun was missing. They suspect that c-Jun works in part by activating Sox-2, as this protein also inhibits myelination.....

No comments:

Opinions – Suggestions - Remarks