Gene silencing prevents its first human disease

The discovery over a decade ago that snippets of RNA can be used as gene silencers in worms garnered a Nobel prize in 2006. Now, for the first time, RNA interference (RNAi) has been proven effective against a human disease – a common respiratory virus.

Under RNAi, short strands of RNA are added to cells to destroy any native RNA molecules with a complementary sequence of letters. Since genes use RNA molecules to make proteins, these snippets effectively “silence” genes that carry the same sequence. In animals, RNAi has shown promise, but progress in people has been slow.

John DeVincenzo studies paediatric infectious disease at the University of Tennessee Health Science Center in Memphis. He and his colleagues tested the ability of short interfering RNA (siRNA) to inhibit viruses of the respiratory tract, where cells are exceptionally willing to take up RNA snippets.

Eighty-five healthy adults were given a nasal spray containing either a placebo or siRNA designed to silence one of the genes of respiratory syncytial virus (RSV), which is the leading cause of infant hospitalisation in the US but fairly harmless in healthy adults.

Delivery issue

They were to use the spray daily for five days. On day two, all the volunteers were infected with live RSV. By day 11, just 44 per cent of those who received the RNAi nasal spray had RSV infections, compared with 71 per cent of the placebo group.

RNAi can trigger an immune response, which might have helped keep infections at bay. But blood samples showed that the risk of RSV infection did not depend on levels of immune molecules, suggesting that RNAi’s protective effect was due to the silencing of genes.

The team is now testing the therapy in lung-transplant patients, who take immunity-suppressing drugs that can make RSV infections deadly. DeVincenzo also hopes to test the therapy in infants soon.

For non-respiratory diseases, however, new ways of getting RNA into the target cells are still needed. “Delivery has always been the big issue for RNAi,” says John Rossi, a molecular geneticist at City of Hope medical centre in Duarte, California, who is testing RNAi’s potential to fight HIV.

Journal reference: Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0912186107

via Gene silencing prevents its first human disease – health – 26 April 2010 – New Scientist.

Revealed: The secret of how worms re-grow amputated body parts… and how humans could one day do the same

Scientists have discovered the gene that allows a worm to regenerate its own body parts after they are amputated, it was announced today.

The research into how Planarian worms can re-grow body parts – including a whole head and brain – could one day make it possible to regenerate old or damaged human organs and tissues, the University of Nottingham said.

The research, led by Dr Aziz Aboobaker, a Research Councils UK Fellow in the university’s School of Biology, shows a gene called ‘Smed-prep’ is essential for correctly regenerating a head and brain in Planarian worms.

The worms have the unusual ability to regenerate body parts, including a head and brain, following amputation.

They contain adult stem cells that are constantly dividing and can become all of the missing cell types.

They also have the right set of genes working to make this happen as it should so that when they re-grow body parts they end up in the right place and have the correct size, shape and orientation, the research showed.

The study is published today in the open access journal PLoS Genetics.

Dr Aboobaker said: ‘These amazing worms offer us the opportunity to observe tissue regeneration in a very simple animal that can regenerate itself to a remarkable extent and does so as a matter of course.

via Revealed: The secret of how worms re-grow amputated body parts… and how humans could one day do the same | Mail Online.

Scientists learn to block pain at its source

A substance similar to capsaicin, which gives chili peppers their heat, is generated at the site of pain in the human body. Scientists at The University of Texas Health Science Center at San Antonio have discovered how to block these capsaicin-like molecules and created a new class of non-addictive painkillers.

The findings were published April 26 in the Journal of Clinical Investigation. The senior investigator was Kenneth Hargreaves, D.D.S., Ph.D., professor and chair of the Department of Endodontics in the Dental School at the UT Health Science Center. Amol M. Patwardhan, M.B.B.S., Ph.D., a graduate of the Health Science Center’s Department of Pharmacology who worked under Dr. Hargreaves’ supervision, is the lead author.

“Nearly everyone will experience persistent pain at some point in their lifetime,” Dr. Hargreaves said. “Our findings are truly exciting because they will offer physicians, dentists and patients more options in prescription pain medications. In addition, they may help circumvent the problem of addiction and dependency to pain medications, and will have the potential to benefit millions of people who suffer from chronic pain every day.”

A ‘complex epidemic’

Pain has been called a “complex epidemic” in the United States. Nearly 50 million Americans live with chronic pain caused by disease or injury. Few physicians or dentists specialize in the field of pain medicine. With pain medication options largely limited to opioids (such as morphine) and aspirin-like drugs, some patients become addicted or dependent upon these drugs, or suffer side effects such as kidney or liver damage.

Researchers at the UT Health Science Center found a new family of fatty acids, produced by the body itself, that play an important role in the biology of pain.

“Capsaicin is an ingredient in hot chili peppers and causes pain by activating a receptor called transient potential vanilloid 1 (TRPV1). We started out seeking the answer to the question “Why is TRPV1 consistently activated in the body upon injury or painful heat? We wanted to know how skin cells talk to pain neurons,” Dr. Hargreaves said. “What we found was much more surprising and exciting. We have discovered a family of endogenous capsaicin-like molecules that are naturally released during injury, and now we understand how to block these mechanisms with a new class of non-addictive therapies.” …

“We found that in the skin flaps heated at greater than 43 degrees Celsius, the cells’ pain neurons showed tremendous activity in the wild type, but not in neurons from mice that lacked TRPV1,” Dr. Hargreaves said. He indicated that this novel phenomenon was taking place because the cells, in response to the heat, began to create their own natural endogenous capsaicins, which they later identified as a series of compounds or fatty acids called oxidized linoleic acid metabolites (OLAMs).

Linoleic acid is one of the most abundant fatty acids in the human body. Under conditions such as inflammation, low blood pressure and some other illnesses, linoleic acid is rapidly oxidized to form biologically active metabolites. However, little else is understood about these substances. The metabolites that were consistently seen in increased amounts in the mouse skin biopsies exposed to heat temperatures greater than 43 degrees Celsius are called 9- and 13-HODE (hydroxyoctadecadienoic acid).

‘Major breakthrough’

“This is a major breakthrough in understanding the mechanisms of pain and how to more effectively treat it,” Dr. Hargreaves said. “These data demonstrate, for the first time, that OLAMs constitute a new family of naturally occurring capsaicin-like agents, and may explain the role of these substances in many pain conditions. This hypothesis suggests that agents blocking either the production or action of these substances could lead to new therapies and pharmacological interventions for various inflammatory diseases and pain disorders such as arthritis, fibromyalgia and others, including pain associated with cancer.”

The research has led Dr. Hargreaves’ team to develop two new classes of analgesics using drugs that either block the synthesis of OLAMs or antibodies that inactivate them. These drugs could eventually come in the form of a topical agent, or a pill or liquid that could be ingested, or in the form of an injection. Both approaches have the potential to block pain at its source, unlike opioid narcotics that travel to the brain and affect the central nervous system.

via Scientists learn to block pain at its source.

Study finds body’s response to repetitive laughter is similar to the effect of repetitive exercise

Laughter is a highly complex process. Joyous or mirthful laughter is considered a positive stress (eustress) that involves complicated brain activities leading to a positive effect on health. Norman Cousins first suggested the idea that humor and the associated laughter can benefit a person’s health in the 1970s. His ground-breaking work, as a layperson diagnosed with an autoimmune disease, documented his use of laughter in treating himself—with medical approval and oversight—into remission. He published his personal research results in the New England Journal of Medicine and is considered one of the original architects of mind-body medicine.

Dr. Lee S. Berk, a preventive care specialist and psychoneuroimmunology researcher at Loma Linda University’s Schools of Allied Health (SAHP) and Medicine, and director of the molecular research lab at SAHP, Loma Linda, CA, and Dr. Stanley Tan have picked up where Cousins left off. Since the 1980s, they have been studying the human body’s response to mirthful laughter and have found that laughter helps optimize many of the functions of various body systems. Berk and his colleagues were the first to establish that laughter helps optimize the hormones in the endocrine system, including decreasing the levels of cortisol and epinephrine, which lead to stress reduction.

They have also shown that laughter has a positive effect on modulating components of the immune system, including increased production of antibodies and activation of the body’s protective cells, including T-cells and especially Natural Killer cells’ killing activity of tumor cells. Their studies have shown that repetitious “mirthful laughter,” which they call Laughercise©, causes the body to respond in a way similar to moderate physical exercise. Laughercise© enhances your mood, decreases stress hormones, enhances immune activity, lowers bad cholesterol and systolic blood pressure, and raises good cholesterol (HDL).

As Berk explains, “We are finally starting to realize that our everyday behaviors and emotions are modulating our bodies in many ways.” His latest research expands the role of laughter even further. …

via Study finds body’s response to repetitive laughter is similar to the effect of repetitive exercise.

Physicists capture first images of atomic spin

Though scientists argue that the emerging technology of spintronics may trump conventional electronics for building the next generation of faster, smaller, more efficient computers and high-tech devices, no one has actually seen the spin—a quantum mechanical property of electrons—in individual atoms until now.

In a study published as an Advance Online Publication in the journal Nature Nanotechnology on Sunday, physicists at Ohio University and the University of Hamburg in Germany present the first images of spin in action.

The researchers used a custom-built microscope with an iron-coated tip to manipulate cobalt atoms on a plate of manganese. Through scanning tunneling microscopy, the team repositioned individual cobalt atoms on a surface that changed the direction of the electrons’ spin. Images captured by the scientists showed that the atoms appeared as a single protrusion if the spin direction was upward, and as double protrusions with equal heights when the spin direction was downward.

The study suggests that scientists can observe and manipulate spin, a finding that may impact future development of nanoscale magnetic storage, quantum computers and spintronic devices.

“Different directions in spin can mean different states for data storage,” said Saw-Wai Hla, an associate professor of physics and astronomy in Ohio University’s Nanoscale and Quantum Phenomena Institute and one of the primary investigators on the study. “The memory devices of current computers involve tens of thousands of atoms. In the future, we may be able to use one atom and change the power of the computer by the thousands.”

Unlike electronic devices, which give off heat, spintronic-based devices are expected to experience less power dissipation.

The experiments were conducted in an ultra-high vacuum at the low temperature of 10 Kelvin, with the use of liquid helium. Researchers will need to observe the phenomenon at room temperature before it can be used in computer hard drives.

But the new study suggests a path to that application, said study lead author Andre Kubetzka of the University of Hamburg. To image spin direction, the team not only used a new technique but also a manganese surface with a spin that, in turn, allowed the scientists to manipulate the spin of the cobalt atoms under study.

“The combination of atom manipulation and spin sensitivity gives a new perspective of constructing atomic-scale structures and investigating their magnetic properties,” Kubetzka said. …

via OHIO: Research | Physicists capture first images of atomic spin.

US Republicans block debate of finance rules reform

US Republican senators have blocked moves to start a debate on a bill to introduce the most significant reforms to financial regulations for 60 years.

Needing 60 votes in the 100-seat Senate to begin debating the bill, Democratic leaders fell three votes short.

Democratic Senator Ben Nelson joined 39 Republicans in voting against it.

Republicans says the bill does not go far enough in its reforms, while Democrats say their opponents want to protect wealthy corporate interests.

Both parties say they expect the overhaul eventually will be approved.

Correspondents say that with Wall Street reeling from a fraud case against Goldman Sachs they are eager to act before November’s Congressional elections.

Goldman executives are due to appear before a Senate committee later. On Monday, the committee said the bank had made billions of dollars at its clients’ expense during the housing market collapse. …

via BBC News – US Republicans block debate of finance rules reform.

Robot vessels used to cap Gulf of Mexico oil leak

Robotic submersibles are being used to try to stop oil leaking into the Gulf of Mexico from a damaged well almost a mile (1.5km) below the surface.

Some 1,000 barrels (42,000 gallons) of oil a day have been gushing from the well since a drilling rig exploded and sank off the Louisiana coast last week.

British oil company BP, which leased the rig, said the “first-of-its-kind” attempt would take 24 to 36 hours.

A nearby oil platform has been evacuated as a precaution.

Workers on the rig, the Ocean Endeavour, were taken away because the oil slick was coming dangerously close, said the US Minerals Management Service.

Conservation experts say the oil has the potential to damage beaches, barrier islands, wetlands and wildlife reserves along hundreds of miles of coastline in four US states.

Whales have been spotted near the spill but they did not appear to be in distress.

For now, the weather conditions are keeping the oil away from the shore and it is hoped the waves will break up the heavy crude oil, allowing it to harden and sink back to the ocean floor.

The oil is not expected to reach land for at least another three days.

Officials are monitoring the environmental effects by boat and plane.

‘Very serious’

BP – which is responsible under federal law for the clean-up – said it was using four submersible vehicles, equipped with cameras and remote-controlled arms, to try to activate a blow-out preventer – a series of pipes and valves that could stop the leak. …

via BBC News – Robot vessels used to cap Gulf of Mexico oil leak.

Panama’s Noriega is extradited from US to France

The former Panamanian leader, Manuel Noriega, has been extradited to France by the United States after spending more than 20 years in a prison there.

US Secretary of State Hillary Clinton signed a “surrender

warrant” after all judicial challenges were resolved.

French officials later confirmed he was on board an Air France flight to Paris.

A court in France convicted Noriega in his absence in 1999 for laundering money through French banks, though it says he will be granted a new trial.

The 76-year-old had wanted to be sent back to Panama after finishing his 17-year jail sentence in 2007.

But in February the US Supreme Court rejected his final appeal against extradition to France.

The former Panamanian leader, Manuel Noriega, has been extradited to France by the United States after spending more than 20 years in a prison there.

US Secretary of State Hillary Clinton signed a “surrender warrant” after all judicial challenges were resolved.

French officials later confirmed he was on board an Air France flight to Paris.

A court in France convicted Noriega in his absence in 1999 for laundering money through French banks, though it says he will be granted a new trial.

The 76-year-old had wanted to be sent back to Panama after finishing his 17-year jail sentence in 2007.

But in February the US Supreme Court rejected his final appeal against extradition to France.

Panama’s government said it respected the “sovereign decision” the state department took to extradite Noriega.

But it insisted it would seek his return to serve outstanding prison sentences there.

Noriega was escorted onto an Air France passenger jet at Miami International Airport on Monday afternoon, shortly after Mrs Clinton signed the extradition order, US officials said. …

via BBC News – Panama’s Noriega is extradited from US to France.

George W Bush book to tell of ‘flaws and mistakes’

The memoir of former US President George W Bush will be a candid account of his “flaws and mistakes” as well as his achievements, his publishers said. The book, Decision Points, will offer “never-before-heard detail” on some of the key events of Mr Bush’s presidency, Crown Publishers announced.

Due for release in November, the book also covers Mr Bush’s family life. The former Texas governor left office in 2009 with one of the lowest presidential approval ratings ever. Correspondents say his legacy has been damaged by unpopular wars in Iraq and Afghanistan and the global financial crisis.  In a statement, Crown Publishers said Decision Points would centre on 14 decisions Mr Bush made during his eight years in office.

The attacks of 11 September 2001 and devastation caused by Hurricane Katrina are among key events covered, it adds.

… “Since leaving the Oval Office, President Bush has given virtually no interviews or public speeches about his presidency,” the statement said.

“Instead, he has spent almost every day writing Decision Points, a strikingly personal and candid account revealing how and why he made the defining decisions in his consequential presidency and personal life. “The cover features a photograph of Mr Bush standing outside the White House during his presidency, holding a briefing folder. A publishing industry source told the Associated Press news agency that Mr Bush had finished a first draft and was editing the manuscript in his office in Dallas, Texas.The book is due to go on sale on 9 November. Mr Bush will promote it with a nationwide tour. The memoirs of Mr Bush’s wife, Laura, are due out on 4 May.

via BBC News – George W Bush book to tell of ‘flaws and mistakes’.

“Buy my book so I can make even more money.  Suckers.”

How colourful fish could explain why life on Earth is so diverse | Mail Online

Scientists had once believed hamlet fish evolved into different colours because of their specific locations – such as the blue hamlet which is found in the Florida region.

It was thought that falling sea levels in the past could have divided the original species. Then when levels increased the differently evolved species were thrown back together.

But on some reefs as many as seven varieties are found in one place, calling into question the theory that geographical separation was the key to their diversity.

Since different species hotspots overlap and many species have more than one hotspot, the results do not support the theory that hamlets originated independently.

Instead a new study from the University of East Anglia has shown ecological factors, such as competition for food or habitat, may influence how different hamlet species co-exist.

Lead author Dr Ben Holt said the most fascinating aspect was that despite their different colours all the hamlets had more or less identical DNA.

This means the splitting of the species is likely to be at a very early stage – giving scientists a unique opportunity to monitor the hamlets as they continue to evolve.

Dr Holt said: ‘A lot of stuff is fairly well known about evolution but speciation – the evolutionary process by which new species arrive – is pretty unknown.

‘Everything is either one type of species, or evolved into a different species millions of year ago.

‘Many scientists believe hamlets are beginning to evolve into a new species and this latest discovery will shed light on this process.

‘The interest in these type of fish is that they all look so different, but their DNA has shown they are almost the same.

‘This suggests there is an ecological reason for why they are evolving apart even though they are clustered together in some areas.

‘They are not just like people with different hair colour, they could be the beginning of a new species.

‘The interesting question which needs more work is why this happening. It could be to do with the ecology, where they live, what they eat, a number of things.’

The study used data from around 5,000 different surveys taken at roughly 1,000 coral reef sites by volunteer scuba divers working on the REEF project.

via How colourful fish could explain why life on Earth is so diverse | Mail Online.