A gene that makes bugs highly resistant to almost all known antibiotics has been found in bacteria in water supplies in New Delhi used by local people for drinking, washing and cooking, scientists said on Thursday.

The NDM 1 gene, which creates what some experts describe as "super superbugs," has spread to germs that cause cholera and dysentery, and is circulating freely in other bacteria in the Indian city capital of 14 million people, the researchers said.

"The inhabitants of New Delhi are continually being exposed to multidrug-resistant and NDM 1-positive bacteria," said Mark Toleman of Britain's Cardiff University School of Medicine, who published the findings in a study on Thursday.

A "substantial number" of them are consuming such bacteria on a daily basis, he told a briefing in London. "We believe we have discovered a very significant underlying source of NDM 1 in the capital city of India," he said.

NDM 1, or New Delhi metallo-beta-lactamase 1, makes bacteria resistant to almost all antibiotics, including the most powerful class, called carbapenems.

It first emerged in India three years ago and has now spread across the world. It has been found in a wide variety of bugs, including familiar pathogens like Escherichia coli, or E. coli.

No new drugs are on the horizon for at least 5-6 years to tackle it and experts are concerned that only a few major drug companies, such as GlaxoSmithKline and AstraZeneca, still have strong antibiotic development programmes.

Toleman's study, carried out with Cardiff University's Timothy Walsh and published in The Lancet Infectious Diseases journal, investigated how common NDM 1-producing bacteria are in community waste seepage -- such as water pools or rivulets in streets -- and tap water in urban New Delhi.

The researchers collected 171 swabs from seepage water and 50 public tap water samples from sites within a 12 kilometer radius of central New Delhi between September and October 2010.

The NDM 1 gene was found in two of the drinking-water samples and 51 of seepage samples, the researchers said, and bacteria positive for NDM 1 were grown from two drinking-water samples and 12 seepage samples.

"We would expect that perhaps as many as half a million people are carrying NDM 1-producing bacteria as normal (gut) flora in New Dehli alone," Toleman said.

Experts say the spread of superbugs threatens whole swathes of modern medicine, which cannot be practiced if doctors have no effective antibiotics to ward off infections during surgery, intensive care or cancer treatments like chemotherapy.

In a commentary about Walsh and Toleman's findings, Mohd Shahid from Jawaharlal Nehru Medical College and Hospital in Uttar Pradesh, India, said global action was needed.

"The potential for wider international spread of ... NDM 1 is real and should not be ignored," he wrote.

The World Health Organization (WHO) has designated April 7 as World Health Day and under the slogan "No action today, no cure tomorrow" it is campaigning about the risks of life-saving antibiotics losing their healing power.

Teenagers who undergo spine fusion for scoliosis using the newest surgical techniques can expect to be doing well 10 years after surgery, according to a Hospital for Special Surgery study published online ahead of print in the TK issue of the journal Spine. Researchers had thought that the surgery would cause damage to the spine just below the fused discs, but the study showed that this was not the case.

"Fusion for adolescent idiopathic scoliosis using the newer generation spine implants appears to spare junctional disc degeneration and allows patients ten years out to have a relatively normal pain free lifestyle," said Daniel Green, M.D., a pediatric orthopedic surgeon at Hospital for Special Surgery in New York who led the study.

Scoliosis is a condition in which a person's spine is curved. The condition can be classified as congenital (caused by vertebral anomalies present at birth), idiopathic (arising after birth and caused by unknown factors) or neuromuscular, where it is a secondary symptom of another condition such as spina bifida. Starting in the early 1960s and up until the late 1990s, scoliosis was treated with surgery with so-called Harrington rods that were implanted along the spinal column. Starting in the late 1990s, surgeons started using newer techniques to fuse the spinal column together and these straight rods became obsolete. Spinal fusion is basically a procedure where doctors "weld" parts of the spine together, so the vertebral column heals into a single, solid rigid unit.

The modern surgery is superior to the Harrington rods surgery because it allows the spine to be corrected in a much more natural, physiologic way, but there haven't been many studies evaluating how patients who undergo the surgery fare years down the road. To remedy this, HSS investigators conducted a pre- and post-operative MRI analysis in patients undergoing the surgery with modern techniques.

The investigators reviewed all spinal fusions performed by four senior scoliosis surgeons at HSS between 1991 and 1997. Patients were included in the study if they had idiopathic scoliosis, were 21 years or younger and had surgery that had the surgeon approach the patient's spine from the patient's back versus the front or side. Patients had to have fusion of the spine in their lower back (between vertebra T12 and L3).

Thirty-three potential study participants were located and 20 agreed to participate. These patients returned for a physical examination by an orthopedic surgeon that included an MRI. Doctors recorded their medical history with special attention to level and location of pain and whether or not the patient was taking pain medication. Doctors compared the new MRIs to the ones taken ten years prior, before the surgery.

"We wanted to see how the patients were doing ten years down the road, specifically focusing on the part of the spine that didn't have surgery. The standard belief was that the area of the spine just below the surgery would wear out, because of the increased stress that the surgery or the fusion would put on that part of the spine," Dr. Green said. "That isn't what we found. We found that the area of the spine adjacent to the fusion was pretty healthy and didn't show any major degeneration ten years later. While mild degenerative changes were noted in almost every patient, the severe changes that we were concerned that we might find were not there at all."

The investigators also found that patients had good functional scores and maintenance of balance. No patients reported significant lower back pain. No patients took analgesic medications for their pain, with the exception of four patients (20%) who took occasional non-prescription non-steroidal anti-inflammatory drugs.

The investigators say the study results are good news for patients. Dr. Green also said the results may cause worry for investigators and companies who are trying to develop surgeries for scoliosis that do not involve fusing the spine. "There is a lot of research and investment being done looking for new technologies that do not use fusion," Dr. Green said. "This study would suggest that there is a challenge for those trying to do that because the patients doing fusion are doing well."

In a study of twin veterans, antidepressant use has been linked to thicker arteries, possibly contributing to the risk of heart disease and stroke.

Depression can heighten the risk for heart disease, but the effect of antidepressant use revealed by the study is separate and independent from depression itself, says first author Amit Shah, a cardiology fellow at Emory University School of Medicine.

The data suggest that antidepressants may combine with depression for a negative effect on blood vessels, he says. Shah is a researcher working with Viola Vaccarino, chair of the Department of Epidemiology at Emory's Rollins School of Public Health.

The study included 513 middle-aged male twins who both served in the U.S. military during the Vietnam War.

Twins are genetically the same but may be different when it comes to other risk factors such as diet, smoking and exercise, so studying them is a good way to distill out the effects of genetics, Shah says.

Researchers measured carotid intima-media thickness - the thickness of the lining of the main arteries in the neck -- by ultrasound. Among the 59 pairs of twins where only one brother took antidepressants, the one taking the drugs tended to have higher carotid intima-media thickness (IMT), even when standard heart disease risk factors were taken into account.

The effect was seen both in twins with or without a previous heart attack or stroke. A higher level of depressive symptoms was associated with higher IMT only in those taking antidepressants.

"One of the strongest and best-studied factors that thickens someone's arteries is age, and that happens at around 10 microns per year," Shah says. "In our study, users of antidepressants see an average 40 micron increase in IMT, so their carotid arteries are in effect four years older."

Antidepressants' effects on blood vessels may come from changes in serotonin, a chemical that helps some brain cells communicate but also functions outside the brain, Shah says.

The most commonly prescribed antidepressants are selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine (Prozac), which increase the level of serotonin in the brain. Other types of antidepressants also affect serotonin levels, and antidepressants can act on other multi-functional brain chemicals such as norepinephrine.

In the study, researchers saw higher carotid IMT in both participants who used SSRIs (60 per cent of those who took antidepressants) and those who used other types of antidepressants.

Most of the serotonin in the body is found outside the brain, especially in the intestines, Shah notes. In addition, serotonin is stored by platelets, the cells that promote blood clotting, and is released when they bind to a clot. However, serotonin's effects on blood vessels are complex and act in multiple ways. It can either constrict or relax blood vessels, depending on whether the vessels are damaged or not.

"I think we have to keep an open mind about the effects of antidepressants on neurochemicals like serotonin in places outside the brain, such as the vasculature. The body often compensates over time for drugs'' immediate effects," Shah says.

"Antidepressants have a clinical benefit that has been established, so nobody taking these medications should stop based only on these results. This isn't the kind of study where we can know cause and effect, let alone mechanism, and we need to see whether this holds up in other population groups."

A new study has suggested a connection between migraine headaches in children and a heart defect called patent foramen ovale.

Roughly 15% of children suffer from migraines, and approximately one-third of these affected children have migraines with aura, a collection of symptoms that can include weakness, blind spots, and even hallucinations.

Rachel McCandless and colleagues from the Primary Children's Medical Center and the University of Utah studied children 6-18 years old who were diagnosed with migraines between 2008 and 2009. The 109 children enrolled in the study were treated at the Primary Children's Medical Center, which serves kids from Utah, Idaho, Montana, Nevada, Colorado, and parts of Wyoming.

The researchers took two-dimensional echocardiograms of each child's heart, looking for a patent foramen ovale (PFO), a common defect in the wall between the two upper chambers of the heart. Although a PFO is not necessarily dangerous, it can allow unfiltered blood to bypass the lungs and circulate throughout the body.

McCandless explained, "Some adult studies have suggested a link between having a PFO and migraine headaches."

Of the studied children who had migraines with aura, 50% also had a PFO; this is nearly double the PFO rate of the general population. However, only 25 pc of children who had migraines without aura had a PFO.

McCandless and colleagues hypothesize that if a causal relationship can be established, closure of a PFO with a catheter device may help in the treatment of certain kinds of migraines, specifically migraines with aura. It is her hope that "our study will help guide future research about this difficult problem."

The study will be published in The Journal of Paediatrics.

Walnuts are the healthiest of all the nuts and should be eaten more as part of a healthy diet, US scientists say.

Scientists from Pennsylvania told the American Chemical Society that walnuts contain the highest level of antioxidants compared to other nuts.

Antioxidants are known to help protect the body against disease.

The scientists said that all nuts have good nutritional qualities but walnuts are healthier than peanuts, almonds, pecans and pistachios.

Dr Joe Vinson, from the University of Scranton, analysed the antioxidant levels of nine different types of nuts and discovered that a handful of walnuts contained twice as many antioxidants as a handful of any other commonly eaten nut.

He found that these antioxidants were higher in quality and potency than in any other nut.

Antioxidants are good because they stop the chain reactions that damage cells in the body when oxidation occurs.
Roasted nuts

The antioxidants found in walnuts were also two to 15 times as powerful as vitamin E, which is known to protect the body against damaging natural chemicals involved in causing disease, the study says.

Nuts are known to be healthy and nutritious, containing high-quality protein, lots of vitamins and minerals as well as dietary fibre. They are also dairy and gluten-free.

Previous research has shown that regular consumption of small amounts of nuts can reduce the risk of heart disease, some types of cancer, type two diabetes and other health problems.

Dr Vinson said there was another advantage in choosing walnuts as a source of antioxidants: "The heat from roasting nuts generally reduces the quality of the antioxidants.

"People usually eat walnuts raw or unroasted, and get the full effectiveness of those antioxidants."