Letters: Blood and ME
Renee Twombly’s article ‘The trouble with ME’ (14 May) draws attention
to the diversity of opinion which characterises the disorder. At one end
of the spectrum are the viral/immunological theorists while the other extreme
might be typified by Peter Behan’s conclusion that CFS is a metabolic disease.
However, data exist which could bridge the gap between viral infections
and abnormal immune responses on the one hand, and oxygen scarcity and
reduced metabolic rates on the other.
It is assumed that normal metabolism of all tissue is dependent on a
supply of oxygen commensurate with the normal metabolic activity of the
tissue. This implies a need for normal capillary blood flow. Several authors
have emphasised that the brain has no provision for the storage of oxygen
or glucose and normal neuronal function is absolutely dependent on a continued
supply of those essential metabolites, via the capillary network.
Nondiscocytic red cells impair capillary blood flow and physiological
studies show that not only do shape-changed erythrocytes reduce capillary
flow velocity but they also have a reduced capacity for oxygen uptake and
release. Some viral infections cause changes in red cell shape and it seems
that increased concentration of plasma immunoglobulins has an echinocyte-transforming
effect on red cells.
A 1986 report showed that the flow properties of blood from ME patients
were abnormal when they were acutely unwell. Other observations on blood
samples from ME patients residing in Australia, New Zealand, South Africa,
The Netherlands, the United Kingdom and the United States of America showed
the presence of increased percentages of nondiscocytes. Such cells will
impair capillary blood flow and appear to be symptom-provoking as the severity
of patients’ symptoms is lessened when the percentage of nondiscocytes
is reduced.
The idea of nondiscocytic impairment of capillary blood flow is supported
by the results of studies using single photon emission computed tomography
(SPECT) in ME patients in Brtain and in CFS patients in the US. Surprisingly,
no SPECT study emphasises the consequences of impaired cerebral blood flow
for neuronal function.
Unless it is argued that capillary blood flow is not an important factor
in normal physiology, it seems that the information needed to understand
the metabolic nature of ME has been available for some time.
L. O. Simpson Otago Medical School University of Otago, New Zealand
Letters: Road referenda
I am grateful to M. W. Westerhuis for adding his voice in support of
local democracy and proclaiming his organisation’s commitment to an environmental
agenda (Letters, 25 June).
He will have a lot of explaining to do to link environmental responsibility
to his support for 12 000 kilometres of new motorway in Europe, and even
more to explain his organisation’s strategy for reducing CO2
emissions from the road transport sector. Nevertheless, I wish him luck
and look forward to IRF sponsored referenda in areas scheduled for new roads.
If the Swiss referendum in February resulting in a transit lorry ban is
anything to go by, we could see a welcome reduction in road construction
in the future.
John Whitelegg Lancaster
Letters: Road referenda
If roads and cars represent an ‘aspiration to freedom and prosperity’,
then how far is this the product of the car lobby? Car advertising constantly
depicts cars in beautiful, natural surroundings, on an open road without
another car in sight. Is this consistent with modern patterns of car use?
If there was a bit more honesty, people might not believe driving anywhere
at any time to be environmentally benign.
Liz Elliot Chorleywood, Hertfordshire
Letters: Pigs aren't people
The article entitled ‘The organ factory of the future?’ (18 June) mentions
some towering obstacles to be overcome before the transplanting of genetically
engineered animal organs into humans can become a reality.
One such obstacle is that pig liver contains uricase which breaks down
uric acid (the end product of urine metabolism in humans) to allantoin.
The pig is also probably the only species whose liver lacks the enzyme guanase,
a key enzyme in controlling guanine ribonucleotide concentrations which
regulate many cellular functions – including the immune response. An equally
important consideration is the activity of aldehyde oxidase which degrades
drugs such as cyclophosphamide and methotrexate to inactive metabolites.
Aldehyde oxidase activity in the human liver is far lower than in most
non-primates.
More importantly, pig kidney is almost unique in lacking the proximal
tubule brush-border anion exchanges which co-transport uric acid, so that
while human kidney reabsorbs around 90 per cent of uric acid, pig kidney
actually secretes it. Certainly this would eliminate the uric acid bolus
that has accumulated in renal failure, but the urinary overload could easily
precipitate acute uric acid nephropathy/renal failure. Of equal, if not
greater, concern is the implication for therapeutic levels of drugs having
affinities for this important luminal anion exchanger, which is absent in
pig kidney.
Consequently, there may be a much longer way to go than is currently
envisaged before surgeons’ dreams can become reality.
Anne Simmonds Guy’s Hospital, London Francoise Roch-Ramel Institut de
Pharmacologie, Lausanne
Letters: Pigs aren't people
In an age of supposed respect for the natural world and the creatures
within it, the research on xenotransplantation stands out like a sore thumb.
Are we really set to become total parasites? Because that’s what we’re
talking about. Laboratories filled with sad humano-pigs awaiting the removal
of their vital organs, so that we humans may, and only may, prolong our
lives for a year or two.
Genetic engineering of animals – be they farm animals designed for increased
productivity, or laboratory animals designed to model human disease – runs
totally counter to the far more positive attitude to animals which society
is starting to adopt.
Joyce D’Silva Compassion in World Farming Petersfield, Hampshire
Letters: Biodiesel boob
Your Letters page of 2 July wrongly attributes to me a letter promoting
the virtues of biodiesel. The letter was written by Nick Tapp of the British
Association of Bio Fuels and Oils, and copied to me for information; presumably
my name was at the foot of the letter as a result, and used in error.
My view is that although the idea of renewable sourcing of automotive
fuels appears an attractive idea, a full lifecycle assessment of biodiesel
production suggests the energy inputs to the production process are of the
same order of magnitude as the output. In other words, it doesn’t make sense
in energy terms.
Proponents of biodiesel suggest that production could be justified by
factoring in the by-products of the process (glycerine and rapeseed meal)
and using EC subsidies for growing nonfood crops. However, the pressure
for biofuels is coming not from environmentalists, but from farmers.
Tim Brown National Society for Clean Air and Environmental Protection
Brighton
Letters: Hard graft
In the article by Sarah Bunney, Katherine Wright is said to criticise
the view that Upper Palaeolithic hunter-gatherers chose to settle down and
farm because of the ease and attractiveness of cereal farming (New 杏吧原创,
Science, 25 June). This view rested on the assumption that hunter-gatherers
led a Hobbesian ‘nasty, brutish and short’ existence and that their life
was a constant search for food, a view discredited by the work of R. B.
Lee among the !Kung Bushmen of the Kalahari Desert in the early 1960s.
It has been understood by archaeologists that this view was untenable
since at least as early as the publication of Binford’s seminal study, ‘Post-Pleistocene
Adaptations’, in 1968. This was reinforced by studies by K. V. Flannery
published in 1969 and 1973.
The labour involved in the processing of grain was obvious to everyone
who considered the problem, as was the necessity of a sedentary lifestyle
for those dependent on grain as a dietary staple – as was pointed out by
Flannery in one of archaeology’s most quoted passages, ‘After all, where
can you go with a . . . (tonne) . . . of cleaned wheat?’
The role of population expansion in the origin of the Neolithic was
highlighted by M. N. Cohen in his book The Food Crisis in Prehistory (1977).
In 1989 Molleson demonstrated the effects of the hand grinding of grain
on the skeleton. In short, the view which Wright is said to criticise has
had no credence among archaeologists since at least the mid-1970s, and,
contrary to the rather surprising assertion attributed to Wright, the majority
of scholars have long held the views which she has expressed.
Rupert L. Chapman III Benfleet, Essex
Letters: Lost over looper
I, too, am worried about the release of the genetically engineered AcNPV
virus at Wytham and agree that there are questions that require answering;
moreover, I cannot understand why the cabbage looper, Trichoplusia ni, is
claimed as a major pest of cabbages and why the Wytham experiment involves
this species (Focus, 25 June).
In more than forty years of moth trapping I have never encountered Trichoplusia
ni in Britain. Skinner (Colour Identification Guide to Moths of the British
Isles, 1984) writes of this species, ‘An uncommon and irregular visitor,
found mostly in southern England . . . The most favoured years were 1982
(69), 1953 (20), 1968 (16) and 1952 (11). Four feral larvae have been recorded:
two at Portland, Dorset in 1894: on marigold at Teignmouth, Devon, on 18
August 1968; and on sea rocket at Dawlish, Devon, on 25 August 1968.’
Hardly a major pest of cabbages, at least not British cabbages. Indeed
I would rejoice in finding one on the cabbages in my garden.
Denis Owen Oxford Brookes University
Letters: Lost over looper
Andy Coghlan writes: The Institute of Virology and Environmental Microbiology
acknowledges that the cabbage looper is rare in Britain, but says that the
species is a serious pest of cotton, cabbages and other legumes in tropical
and subtropical regions. The team at the IVEM is using the looper mainly
because it is easy to work with experimentally. However, the investigators
say that the virus they are developing as a pesticide might ultimately be
used in regions such as Central America where the looper is a problem.
Letters: Prescient skipping
There has been much correspondence on the subject of who or what was
the first object to appear on television (Letters, 14 May and 4 June) and
I have been struck by the thought that things could so easily have been
different.
I have an early textbook in which apparatus easily recognisable as a
television receiver/transmitter is described (although the word ‘television’
was obviously not in use at that time). The apparatus is of the scanning
type, like that currently in use albeit not with interlaced scan as with
modern receivers; more importantly it is quite unlike that attributed to
Baird many years later.
The description, written in Patent Office-style prose, describes how
the scanning is to be accomplished by a beam of light projected by a mechanism
not unlike a mirror galvanometer with deflection coils in two planes, and
describes how ‘an image of a girl skipping’ in York could be viewed simultaneously
in London. This invention is credited to Professors Ayrton and Perry.
To me the really interesting thing is that this was published in 1888,
which predates Baird somewhat; my copy was actually printed in 1900. It
is intriguing to think that the ‘girl in York’ could easily have scooped
the ‘first appearance’ contest and changed history.
Alan Gamble Ormskirk, Lancashire
Letters: Attic paras
Re ‘Parachutes and straw hats’ (Review, 18 June). Heracles won the princess
Iole in an archery contest, but was bilked of his prize by her father, King
Eurytus. Heracles and his friends attacked and pillaged Oechalia, and killed
the king and his son. Determined not to surrender to Heracles, Iole leapt
from the city wall. She survived because her skirts billowed out and broke
her fall.
This aspect of the story would seem to indicate the Greeks were aware
of the principle of the parachute. It was recorded by Plutarch, but must
have been circulating much earlier.
D. G. Shouler Wellington, New Zealand
Letters: Correction
The mighty electron failed us in ‘Anatomy of a metal’ (Inside Science
72, 11 June). After final proofs, a text-wrap error skimmed off three lines
on page 1. The first line of text immediately below the diagram in the first
column should have read ‘colour, their ability to resist corrosion and’,
in the second column ‘ordinary conditions – becomes a metal un-‘ and the
third ‘physicist, and then modified by Niels Bohr,’
Letters: Odd women
I greatly enjoyed Jim Baggott’s article, ‘The disappearing dons’ (Forum,
18 June), and share his regrets. Indeed, I would go further and say that
we destroy ‘these quite remarkable creatures’ at our peril, for they were,
and are, some of our most original thinkers and innovators. But why does
he ignore the women, and tell us that his dons were ‘exclusively male’?
They were not, and are not. I see why women are invisible; even now men
seem to be totally unwilling to abandon the idea that they alone count.
Baggott’s examples relate to the 20th century, so he is plainly not
describing a past time when women were barred from teaching in universities.
Women in this century have been quite as scholarly and quite as odd and
idiosyncratic, though perhaps in some different ways, as the men. Why not
acknowledge their existence?
My dismay at your journal’s masculine viewpoint is increased by another
article in the same issue, ‘Taking the measure of the growing population’
(Technology). It is clear that the author is solely concerned with the increasing
height of males, and the different measures now needed for their chairs,
car seats, and so on. Why not also consider fitting chairs and car seats
to women’s frames? As a woman user of libraries I am constantly sitting
uncomfortably on chairs of the wrong height, designed for men. I know another
woman scholar, shorter than myself, who often has to sit on her knees, and
was once reprimanded in one of our great libraries for not sitting properly.
Joan Thirsk Tonbridge, Kent
Letters: Noncentric
At the risk of appearing ‘Eurocentric’ (Letters, 2 July), I am still
convinced by Lewis Wolpert’s arguments for the unique origin of science,
just as I am convinced about the unique origin of human language – yet that
doesn’t make me ‘Afrocentric’.
Notice that Wolpert’s science is very nonpragmatic in character, concerned
to understand how the natural world is, without worrying too much how that
affects human life, or what moral lessons we should draw from it. I think
Derrick dislikes this ‘separation of man from nature’.
Wolpert never called Chinese technology ‘primitive’ – rather he referred
to the Chinese as ‘brilliant engineers’. His careful contrasts between ‘science’
and ‘technology’ as well as ‘science’ and ‘common-sense’ have passed Reg
Dennick by completely, and Wolpert’s central claim – that science (as he,
I and every dictionary define it) is unique – receives a curt dismissal
as a ‘schism’.
Nicholas Bone University of Oxford