Sunday, July 17, 2011

Another nanoparticle study

This is another study purporting to show bad effects from motor vehicle exhausts. Sadly, the topic has become involved with Greenie beliefs. Read here what happens if your findings don't suit the Greenie agenda. In the circumstances all findings in the area have to be treated with a priori suspicion. Only findings that suit the Greenie agenda are likely to get published.

Aside from a priori doubts, however, there are clear weaknesses in this study particularly. The "sample" size of only 16 is amazingly small and could easily give unreplicable results.

And what they found borders on the trivial. They found that inhaling diesel exhaust increased blood pressure and reduced the tendency of blood vessels to dilate. I think being made to inhale diesel exhaust would raise my blood pressure too! The smell alone is pretty obnoxious.

And (pace the Daily Mail) there was no evidence of the blood vessel effects doing any wider damage

Combustion-derived nanoparticulate induces the adverse vascular effects of diesel exhaust inhalation

By Nicholas L. Mills et al.


Aim: Exposure to road traffic and air pollution may be a trigger of acute myocardial infarction, but the individual pollutants responsible for this effect have not been established. We assess the role of combustion-derived-nanoparticles in mediating the adverse cardiovascular effects of air pollution.

Methods and results: To determine the in vivo effects of inhalation of diesel exhaust components, 16 healthy volunteers were exposed to (i) dilute diesel exhaust, (ii) pure carbon nanoparticulate, (iii) filtered diesel exhaust, or (iv) filtered air, in a randomized double blind cross-over study.

Following each exposure, forearm blood flow was measured during intra-brachial bradykinin, acetylcholine, sodium nitroprusside, and verapamil infusions.

Compared with filtered air, inhalation of diesel exhaust increased systolic blood pressure (145 ± 4 vs. 133 ± 3 mmHg, P< 0.05) and attenuated vasodilatation to bradykinin (P= 0.005), acetylcholine (P= 0.008), and sodium nitroprusside (P< 0.001).

Exposure to pure carbon nanoparticulate or filtered exhaust had no effect on endothelium-dependent or -independent vasodilatation.

To determine the direct vascular effects of nanoparticulate, isolated rat aortic rings (n= 6–9 per group) were assessed in vitro by wire myography and exposed to diesel exhaust particulate, pure carbon nanoparticulate and vehicle.

Compared with vehicle, diesel exhaust particulate (but not pure carbon nanoparticulate) attenuated both acetylcholine (P< 0.001) and sodium-nitroprusside (P= 0.019)-induced vasorelaxation. These effects were partially attributable to both soluble and insoluble components of the particulate.

Conclusion: Combustion-derived nanoparticulate appears to predominately mediate the adverse vascular effects of diesel exhaust inhalation. This provides a rationale for testing environmental health interventions targeted at reducing traffic-derived particulate emissions.


The 'super tomatoes' fortified with minerals that combat cancer

This is just speculation. No proof of any benefit

It is the perfect excuse to have that last piece of pizza. ‘Super tomatoes’ fortified with minerals have just hit shelves across the UK.

Ordinary tomatoes – which are already viewed as one of the superfoods – have been enriched with selenium, a powerful anti-oxidant that boosts the immune system and may prevent cancer. The mineral, found naturally in foods such as Brazil nuts, shellfish and liver, is also important for the thyroid gland, which determines how quickly the body uses energy and also produces proteins.

The new tomatoes, which cost £1.99 for 300g, have gone on sale in Marks & Spencer. Food scientists for the company turned their attention to the mineral because it is lacking in UK diets. Low concentrations in farm soil means little of the mineral finds its way into home-grown foods. There is evidence that a deficiency may lead to heart disease and, while it does not tend to directly cause illnesses, it can make the body more likely to catch infections.

Dr Carina Norris, of the Nutrition Society, said the tomatoes were a great way to get the nutrient into our diets. ‘Selenium plays an important role in supporting the immune system, and it’s thought that getting adequate selenium reduces our risk of cancer,’ she said.

‘But many people in the UK don’t get enough from their diets – the latest data suggests the average person consumes well below the (daily) target of 60microgrammes for women and 75 for men.

‘So to get a “difficult” nutrient like selenium into a food that more or less everyone eats – such as tomatoes – has to be a good thing.’ The tomato is the latest product developed by Marks & Spencer to try to improve customers’ health.

It follows the store’s Vitamin D-enriched milk, yoghurts and juice developed to help tackle health problems caused by a lack of sunshine, such as rickets.

M&S produce technologist Dr Simon Coupe said: ‘We want to make it easy for our customers to eat healthily and our new tomatoes are win-win – the taste of summer with a boost for your immune system.’


1 comment:

Wireless.Phil said...

New rice?

Climate Adaptation of Rice 4 days ago

Seattle – Rice – which provides nearly half the daily calories for the world’s population – could become adapted to climate change and some catastrophic events by colonizing its seeds or plants with the spores of tiny naturally occurring fungi, just-published U.S. Geological Survey-led research shows.