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Wed, May 25, 2005
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Mother’s Milk Lowers Blood Pressure
Lattice Trap Can Improve Optical Clocks
Stem Cell Hope for Liver Disease

Mother’s Milk Lowers Blood Pressure
Being breastfed as a baby has a beneficial impact on blood pressure, a study suggests.
According to BBC News website, researchers found it was as good for children’s blood pressure as exercise and cutting salt intake is for adults.
And the longer a baby was breastfeed, the more impact it had on the child’s blood pressure.
The study, of more than 2,000 children by the University of Bristol, is published in the journal Archives of Disease in Childhood.
The researchers studied children from Denmark and Estonia to try to establish whether there was a relationship between breastfeeding and a range of conditions which can lead to coronary heart disease.
There did not appear to be any impact on some of the conditions examined.
But children who had been exclusively breastfed as babies did seem to have lower blood pressure.
The pattern could be seen in both countries, irrespective of the differences in diet and social conditions between the two.
After taking account of children’s differing heights, weights and stages of development, the researchers found babies who had been exclusively breastfed for at least six months had a systolic blood pressure reading on average 1.7mm Hg lower than those who had not.
By comparison cutting salt is thought to reduce adults’ systolic blood pressures by around 1.3mm Hg and physical activity by around 0.7mm Hg.
The impact of breastfeeding on blood pressure also appeared to be more marked the longer babies were breastfed.
The researchers said their findings suggested a direct causal link between breastfeeding and lower blood pressure in older children.

Lattice Trap Can Improve Optical Clocks
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A cloud of laser cooled atoms in the vacuum chamber being cooled by blue laser light. The clock transition is at a red wavelength of 698-nm.
Researchers in Japan have demonstrated a way to trap neutral atoms that could herald a new era in timekeeping. The team believes that an optical clock based on strontium atoms trapped in an optical lattice could lead to clocks that are accurate to one part in 1018, PhysicsWeb.org said.
The gold standard in timekeeping is currently the caesium-133 atomic clock, which is accurate to 1 part in 1015 and is used to define the second.
Optical clocks--based on single trapped ions or cooled atoms--are promising candidates to replace the atomic clock but they are hard to stabilize.
However, this could be about to change thanks to work being carried out by Hidetoshi Katori and colleagues at the University of Tokyo and the National Metrology Institute of Japan.
By trapping a cloud of 10,000 cold strontium atoms at a temperature of just 2 microkelvin in a one-dimensional “optical lattice“ the Japanese team says it has created a highly stable optical clock with an oscillator frequency of 429 terahertz.
The lattice is formed by the peaks and troughs of the standing wave formed by reflecting light with a wavelength of 813.4 nm from a mirror. The atoms are trapped at the peaks of the standing wave.
Trapping the atoms in the lattice enhances the stability of the clock by preventing the collisions between atoms that plague traditional neutral atom clocks. At the same time, the large number of atoms gives a strong signal. Single-ion clocks, on the other hand, emit a weak signal that needs to be averaged over a long time period.

Stem Cell Hope for Liver Disease
Researchers have begun a pioneering trial using patients’ own stem cells to treat their chronic liver disease, BBC News website said.
A team at London’s Hammersmith Hospital is attempting to reverse cirrhosis of the liver by harnessing and enhancing the body’s own repair mechanism.
They are using adult stem cells extracted from patients’ bone marrow to generate new tissue in damaged areas.
A Japanese group is also testing adult stem cells as a treatment for liver fibrosis.
Liver disease is dramatically on the increase in the UK - something doctors mostly blame on burgeoning lifestyles of excess.
Deaths from alcoholic liver disease have doubled in the last 10 years, with figures for the condition in young people increasing eight-fold due to binge drinking.
Add to that a growing obesity problem and a predicted trebling of the disorder from viral hepatitis in the next 20 years and it is clear that this condition is becoming a major challenge for the NHS.
The liver is a forgiving organ and can tolerate, and recover from, a certain amount of abuse so long as the damage is not too advanced.
However, the liver is also rather stoic and there are often no warning signals until it is too late.
There is no equivalent dialysis machine for liver disorders so patients with chronic disease are eventually left with two stark outcomes, organ transplantation or death.
Putting aside the rigors of a transplant operation and a life on immunosuppressant regime, patients often do not even get offered that choice.
Only a few will be deemed suitable for transplant and although there are about 600-700 liver transplants a year, for every donor organ there are 10 patients on the waiting list.