Clipmarks | Silkweaver's 'biology' clips

68 Molecules that hold the key to all Cellular Life

Fri, 05 Sep 2008 01:01:12 GMT

clipped by: Silkweaver
clipper's remarks: Currently, the vast majority of medical research looks to the human genome and proteome for answers, but those answers remain elusive, and perhaps for good reason.

“We have now found instances where the pathogenesis of widespread and chronic diseases can be attributed to a change in the glycome, for example, in the absence of definable changes in the genome or proteome,” Marth said, adding that, as biomedical researchers, “we need to begin to cultivate the integration of disciplines in a holistic and rigorous way in order to perceive and most effectively manipulate the biological mechanisms of health and disease.”

Marth believes that biology should become more integrative both in academic and research settings. “I’m one who believes that we don’t need to sacrifice breadth of knowledge in order to acquire depth of understanding.”

Clip Source: www.physorg.com

Clip Source: www.sciencedaily.com

Why is it that the origins of many serious diseases remain a mystery? In considering that question, a scientist at the University of California, San Diego School of Medicine has come up with a unified molecular view of the indivisible unit of life, the cell, which may provide an answer.

Reviewing findings from multiple disciplines, Jamey Marth, Ph.D., UC San Diego Professor of Cellular and Molecular Medicine and Investigator with the Howard Hughes Medical Institute, realized that only 68 molecular building blocks are used to construct these four fundamental components of cells: the nucleic acids (DNA and RNA), proteins, glycans and lipids.

Like the periodic table of elements, first published in 1869 by Russian chemist Dmitri Mendeleev, is to chemistry, Marth’s visual metaphor offers a new framework for biologists.

These 68 building blocks provide the structural basis for the molecular choreography that constitutes the entire life of a cell

Tags: biology, cell biology

Cell Division Study Resolves 50-year-old Debate

Fri, 05 Sep 2008 00:49:46 GMT

clipped by: Silkweaver
clipper's remarks: This is a basic biology must know breakthrough.

Clip Source: www.sciencedaily.com

A new study at Oregon State University has finally resolved a controversy that cellular biologists have been arguing over for nearly 50 years, with findings that may aid research on everything from birth defects and genetic diseases to the most classic "cell division" issue of them all – cancer.

The exact mechanism that controls how chromosomes in a cell replicate and then divide into two cells, a process fundamental to life, has never been completely pinned down, researchers say.

Two distinct theories were formed, called polar relaxation and equatorial stimulation, to explain this aspect of cell division – and some scientists have spent much of their careers arguing for one side or the other.

Turns out, Zhang said, that both sides were correct. Nature and evolution have actually created a basic way for a cell to divide with a backup system that can work if the other approach fails.

The findings, Zhang said, add significantly to the basic understanding of cell biology

Tags: biology, cell biology

Landmark study opens door to new cancer, aging treatments

Mon, 01 Sep 2008 01:02:41 GMT

clipped by: Silkweaver

Clip Source: www.nature.com

Telomerase protein structure will help research into ageing and cancer.

The part of the enzyme that controls the timing mechanism of cellular ageing has been revealed.

The X-ray crystal structure offers insights into the ageing process of normal cells, and may provide a safer method for treating up to 90% of human cancers.

Clip Source: www.physorg.com

Researchers have attempted for more than a decade to find drugs that shut down telomerase—widely considered the No. 1 target for the development of new cancer treatments—but have been hampered in large part by a lack of knowledge of the enzyme's structure.

In addition to its role in cancer, telomerase holds significant implications for the development of therapies to combat aging and other age-related diseases.

Finding ways to activate telomerase under controlled conditions and allow some cells to begin dividing again could result in healthier, younger-looking tissue that lives longer.

Tags: molecular biology, cancer, anti aging

From Egg to Chicken

Mon, 01 Sep 2008 00:26:32 GMT

clipped by: Silkweaver
clipper's remarks: So... Bottom line, what came first the egg or the chicken?

Clip Source: www.picsyard.com

Can you imagine the progress from an egg to a chick? It’s amazing to see such progress in pictures.

Tags: biology, photography

Scientists find the secret to swatting flies

Sun, 31 Aug 2008 23:54:58 GMT

clipped by: Silkweaver
clipper's remarks: Handily, the research suggests an optimal method for successfully swatting a fly.

"It is best not to swat at the fly's starting position, but rather to aim a bit forward of that to anticipate where the fly is going to jump when it first sees your swatter,"

Clip Source: www.cosmosmagazine.com

Using high-speed video footage, bioengineers have discovered the key to the evasive manoeuvrability of flies – and found the best strategy for swatting them successfully.

Long before the fly leaps, its tiny 'brain' calculates the location of the impending threat, comes up with an escape plan, and places its legs in an optimal position to hop out of the way in the opposite direction. All of this action takes place within about 100 milliseconds after the fly first spots the swatter.

This illustrates how rapidly the fly's brain can process sensory information into an appropriate motor response,

We also found that when the fly makes planning movements prior to take-off, it takes into account its body position at the time it first sees the threat

Clip Source: www.cosmosmagazine.com

The results offer new insight into the nervous system of insects, and suggest that within the fly brain there is a map in which the position of the looming threat "is transformed into an appropriate pattern of leg and body motion prior to take off,

Tags: biology, biomechanics

Researchers turn one form of adult mouse cell directly into another

Wed, 27 Aug 2008 22:18:44 GMT

clipped by: Silkweaver
clipper's remarks: Joan Brugge, Chair of the Department of Cell Biology at Harvard Medical School, said the new study "provides exciting new insights into yet another aspect of cell plasticity that was not appreciated previously and that offers great potential therapeutically. Direct reprogramming represents a more straight-forward strategy to treat diseases involving loss of function of specific cell populations than approaches requiring an intermediate embryonic stem cell," she said.

Clip Source: www.physorg.com

In a feat of biological prestidigitation likely to turn the field of regenerative medicine on its head, Harvard Stem Cell Institute (HSCI) co-director Doug Melton and post doctoral fellow Qiao "Joe" Zhou report having achieved what has long been a dream and ultimate goal of developmental biologists – directly turning one type of fully formed adult cell into another type of adult cell.

The Melton team reports in today's online edition of the journal Nature that, using a technique it is calling "direct reprogramming," the team is able to turn mouse exocrine cells, which make up about 95 percent of the pancreas, into precious and rare insulin-producing beta cells. These beta cells, which comrpise about one percent of the pancreas, are the cells that die off in Type I diabetes.

In addition to its value for the field of regenerative medicine, the work also is a major step forward toward eventually developing a treatment for Type II – and eventually Type I – diabetes

Tags: molecular biology, cell plasticity, regenerative medicine

Future for clean energy lies in 'big bang' of evolution

Tue, 26 Aug 2008 15:45:01 GMT

clipped by: Silkweaver
clipper's remarks: For humans now there is the tantalising possibility of tweaking the photosynthetic reactions of cyanobacteria to produce fuels we want such as hydrogen, alcohols or even hydrocarbons, rather than carbohydrates.
Progress at the research level has been rapid, boosting prospects of harnessing photosynthesis not just for energy but also for manufacturing valuable compounds for the chemical and biotechnology industries. Such research is running on two tracks, one aimed at genetically engineering real plants and cyanobacteria to yield the products we want, and the other to mimic their processes in artificial photosynthetic systems built with human-made components. Both approaches hold great promise and will be pursued in parallel, as was discussed at a recent workshop focusing on the photosynthetic reaction centres of cyanobacteria, organised by the European Science Foundation (ESF).

Clip Source: scienceblogs.com

Clip Source: www.physorg.com

Amid mounting agreement that future clean, "carbon-neutral", energy will rely on efficient conversion of the sun's light energy into fuels and electric power, attention is focusing on one of the most ancient groups of organism, the cyanobacteria.

Dramatic progress has been made over the last decade understanding the fundamental reaction of photosynthesis that evolved in cyanobacteria 3.7 billion years ago, which for the first time used water molecules as a source of electrons to transport energy derived from sunlight, while converting carbon dioxide into oxygen.

The light harvesting systems gave the bacteria their blue ("cyano") colour, and paved the way for plants to evolve by "kidnapping" bacteria to provide their photosynthetic engines, and for animals by liberating oxygen for them to breathe, by splitting water molecules.

Tags: clean energy, molecular biology

Pioneering Research in Neuromorphic Electronics that Function Like the Biological Brain

Mon, 25 Aug 2008 12:36:58 GMT

clipped by: Silkweaver
clipper's remarks: The HRL team's ultimate goal is to build a low-power, compact electronic chip combining a novel analog circuit design and a neuroscience-inspired architecture that can address a wide range of cognitive abilities--perception, planning, decision making, and motor control. In the initial two phases of the SyNAPSE program, the team will translate the neuronal and synaptic functions of the biological cortex into similar microelectronic functions.

Clip Source: www.alzheimer.ca

Clip Source: www.prweb.com

HRL Laboratories, LLC, will begin pioneering research to develop electronics that will simulate the cognitive capabilities and efficiencies of the biological brain.

The daunting undertaking is part of the Defense Advanced Research Project Agency's (DARPA) SyNAPSE, or Systems of Neuromorphic Adaptive Plastic Scalable Electronics, program. HRL will lead a group of industry and university research laboratories with expertise in core areas of neuro and cognitive science in the groundbreaking research.

Despite exponential advances in computing technology over the last decade, the limitations of hardware and architecture prohibit computers from functioning independently in real-world scenarios. The goal of the SyNAPSE program is to bridge biology and electronics and establish a new paradigm for creating more intelligent machines that can interact with, react to, and actually learn from their environments.

Tags: technology, neuromorphic electronics, electronics

The Secret Of Fast Complex Brain Restructuring

Mon, 25 Aug 2008 12:29:42 GMT

clipped by: Silkweaver
clipper's remarks: Up to now, it had been assumed that nerve cells can only exchange information via the synapses which are special contact points. However, synapses require up to two days to become fully functional - a waste of time and energy if the contact is to be broken down again. The brain could take almost 1000 years to develop if a synapse had to mature at each cell contact.

It appears that nerve cells can also obtain information about their neighbours even without a synapse. Neurobiologists Christian Lohmann and Tobias Bonhoeffer from the Max Planck Institute for Neurobiology have now explained how they do that.

The secret to how the information is exchanged: local calcium signals very quickly transmit all the necessary information to the cell. A synapse only actually develops when the cell and the contact point prove to be suitable candidates for long-term contact.

Clip Source: www.physorg.com

Nerve cells constantly create new contact points to their neighbouring cells.

This is how the basic structure of our brain develops. In adults, new contact makes learning and memory possible. However, not all contact between cells is useful - most of it is dismantled again very quickly.

Scientists at the Max Planck Institute for Neurobiology in Martinsried near Munich have now described a completely new technique with which nerve cells can evaluate the quality of the cells they contact in a very time- and energy-saving way.

During brain development, young nerve cells must come into contact with the correct partner cells so that the brain can carry out its complex functions. However, contact between nerve cells is also constantly being set up and dismantled in adults. It is this continuous restructuring of the brain that allows us to learn and to forget.

Tags: neuroscience, molecular biology

On Law and Neuroscience

Mon, 25 Aug 2008 12:06:32 GMT

clipped by: Silkweaver
clipper's remarks: An interesting read describing the influence of evolution theory and neuroscience on basic legal and moral concepts such as responsibility and free will.

Clip Source: darwinianconservatism.blogspot.com

Farahany is a law professor at Vanderbilt University who brings together law, philosophy, and biology in studying the fundamental assumptions about human nature in criminal law.

paper on "Law and Behavioral Morality

In this paper, she considers how research in evolutionary science and neuroscience might influence our view of criminal responsibility and culpability.

She claims that as evolutionary biology and cognitive neuroscience provide biological explanations of human morality, this will strengthen the power of "behavioral morality--the idea that any behavior with a physical cause is either not blameworthy, or is less so.

She seems to assume that "blameworthiness" presupposes "free will" understood as an uncaused cause.

I disagree with her. As I have said in some previous posts, I see no reason to believe that legal responsibility and culpability must rest on the idea of "free will" understood as uncaused cause.

Tags: law, morality, neuroscience

Exploding chromosomes fuel research about evolution of genetic storage

Sat, 23 Aug 2008 13:01:12 GMT

clipped by: Silkweaver
clipper's remarks: Dinoflagellates are stuffed at the core with tightly compacted chromosomes, yet these organisms contain neither histones nor nucleosomes. "What takes care of neutralizing DNA, to allow chromosomes to condense?" Levi-Setti asked. "Most biology books do not tell you."

Other scientists had already identified positively charged atoms called cations as neutralizing factors. They found that dinoflagellate chromosomes explode upon the removal of calcium and magnesium cations.

Levi-Setti has produced the first images of the distribution of these cations in dinoflagellate chromosomes. These images verify that cations, mainly of calcium and magnesium, neutralize DNA's enormous negative charge, and further suggest a critical role in folding the protein as well.

The finding raises questions about the evolution of chromosomes, Rizzo said. "Did dinoflagellates once have histones and then lost them? Or did dinoflagellates never have histones and just 'figured out' a different way to fold lar

Clip Source: www.labspaces.net

Human cells somehow squeeze two meters of double-stranded DNA into the space of a typical chromosome, a package 10,000 times smaller than the volume of genetic material it contains.

"It is like compacting your entire wardrobe into a shoebox," said Riccardo Levi-Setti, Professor Emeritus in Physics at the University of Chicago.

Now research into single-celled, aquatic algae called dinoflagellates is showing that these and related organisms may have evolved more than one way to achieve this feat of genetic packing.

Even so, the evolution of chromosomes in dinoflagellates, humans and other mammals seem to share a common biochemical basis

Packing the whole length of DNA into tiny chromosomes is problematic because DNA carries a negative charge that, unless neutralized, prevents any attempt at folding and coiling due to electrostatic repulsion.

In humans and mammals, proteins called histones partially neutralize the DNA's negative charge.

Tags: genetics, chromosomes, evolution

Transformers - The Nature of Alien Life

Sat, 23 Aug 2008 12:52:47 GMT

clipped by: Silkweaver
clipper's remarks: The driving factor is a pragmatic desire to improve mental capacity. Alien beings may have already reached a point in their evolution where, having exhausted the potential of their biological brains, they have taken the next logical step and opted for robotic brains equipped with artificial intelligence. This brain swap may not be as far off for humans as one might think. In only a few decades, the computer revolution here on Earth has produced supercomputers capable of performing more than a quadrillion calculations per second.

According to research by Hans Moravec, an artificial-intelligence expert at Carnegie Mellon University, that rate trumps the human brain’s estimated top speed of 100 trillion calculations per second. Some scientists speculate that in a few decades, an event called the technological singularity will occur, and machines armed with computer brains will become sentient and surpass human intelligence. Civilizations equipped with technology light-years ahead

Clip Source: kemo-d7.livejournal.com

The existence of a race of sentient alien robots might be
not just possible, but inevitable.

Daniel C. Dennett points out that we do not consider chemicals to be alive. Even self-replicating crystals and clever nanobots are not "living"; we consider them to be completely mechanical. Yet we are made of these non-living, "mechanical" chemicals. Not only are we made of robots, and we still consider ourselves to be valid conscious life, but the evolution of all life is from such mindless robots.

As life is based in biology, and biology in biochemistry, chemistry is based on the cold, non-living laws of physics.

Given the current pace of development, it is easy to imagine artificial life venturing out into the universe and leaving us fragile humans behind.

In fact, we might be living in a "post-biological universe" right now, in which intelligent extraterrestrials somewhere have exchanged organic brains for artificial ones.

Tags: ai, science fiction, alien life

Researchers discover technology that silences genes

Mon, 18 Aug 2008 20:01:29 GMT

clipped by: Silkweaver
clipper's remarks: A safe and reliable gene silencing technology might be a component of a larger arsenal of gene therapies. It is a ground breaking research.

Clip Source: www.physorg.com

Mount Sinai researchers have developed a new gene silencing technology that could be used to target genes that can lead to the development of certain diseases.

This technology could pave the way for preventing diseases where gene dysfunction plays a role.

By being able to silence certain genes, we may be able to suppress genes that can cause diseases such as HIV/AIDS, cancer, inflammation and diseases of the central and peripheral nervous systems.

In the study

discovered that Paramecium bursaria chlorella virus uses a viral protein to modify host DNA packing chromatin and switch host transcription machinery for viral replication.

Based on this finding, researchers were able to develop a new gene targeting technology that effectively suppresses transcriptional expression of targeted genes in human cells, including genes that are linked to the onset of a number of diseases.

Tags: gnetics, medicine, molecular biology

A Study of Women Scientists, Part 4

Mon, 18 Aug 2008 02:36:44 GMT

clipped by: Silkweaver
clipper's remarks: There are many more...

Clip Source: sciencewomen.blogspot.com

Sophie Germain (1776-1831), mathematician who was forced to take on the identity of a man

Grace Hopper (1906-1992), pioneer computer scientist and Rear Admiral in the US Navy

Dorothy Hodgkin (1910-1994), one of the main founders of protein crystallography

Hypatia of Alexandria (370-415), mathematician and astronomer who was killed by a mob, who "felt threatened by her scholarship and scientific knowledge"

Hedy Lamarr (1913-2000), actress and inventor of "frequency hopping" method that is used in modern communication technology

Ada, Countess Lovelace (1915-1852), founder of scientific computing

Lise Meitner (1878-1968), physicist who described nuclear fission

Rosalyn Yalow (1921-), "medical physicist" who "won a Nobel prize for her work developing the radioimmunoassay technique"

Christiane Nusslein Volhard (1942 - ), developmental biologist and Director of the Max Planck Institute for Experimental Biology

Rita Levi-Montalcini (1909 - ), biologist who first isolated nerve grown factor

Tags: female scientists

Cooking and Cognition: How Humans Got So Smart

Fri, 15 Aug 2008 21:55:09 GMT

clipped by: Silkweaver
clipper's remarks: We started innovating. We tried different materials, such as bone, and invented many new tools, including needles for beadwork. Responding to, presumably, our first abstract thoughts, we started creating art and maybe even religion.

To understand what caused the cognitive spurt, Khaitovich and colleagues examined chemical brain processes known to have changed in the past 200,000 years. Comparing apes and humans, they found the most robust differences were for processes involved in energy metabolism.

The finding suggests that increased access to calories spurred our cognitive advances, said Khaitovich, carefully adding that definitive claims of causation are premature.

The research is detailed in the August 2008 issue of Genome Biology.

Clip Source: www.livescience.com

After two tremendous growth spurts — one in size, followed by an even more important one in cognitive ability — the human brain is now a lot like a teenage boy.

It consumes huge amounts of calories, is rather temperamental and, when harnessed just right, exhibits incredible prowess.

The brain's roaring metabolism, possibly stimulated by early man's invention of cooking, may be the main factor behind our most critical cognitive leap, new research suggests.

About 2 million years ago, the human brain rapidly increased its mass until it was double the size of other primate brains.

"This happened because we started to eat better food, like eating more meat," said researcher Philipp Khaitovich

For a long time, we were pretty dumb. Humans did little but make "the same very boring stone tools for almost 2 million years," he said. Then, only about 150,000 years ago, a different type of spurt happened — our big brains suddenly got smart.

Tags: brain, culture, intelligence, nutrition