Let’s look inside your brain…
We broke the genetic code when we
unraveled the human genome, but that most certainly is not the end of the
research that needs to be done on us, the species that prides itself on
being the top of the food chain.
The new goal is to learn how all 85
billion neurons in the human brain are wired up, and we have a chap called
Jeff Lichtman working in a laboratory at Harvard University who is
systematically slicing up brains to see if he can work out the human wiring
diagram. And that is not an easy job. This is called the human
Jeff Lichtman began many years ago by
slicing up mouse brains to see if he could demonstrate all the electrical
connections in our rodent friends. The initial results were promising, so
he shifted the research to the human brain. Incidentally, to complete every
part of the mouse brain study he calculated how long it might take to image
every slice of a 1 centimeter mouse brain. The answer was 7000 years!
Hoping that he could complete the study
in his own lifetime, he began the human research. The human brain is
another story. There are 85 billion neurons in the 1.4 kilograms of squishy
tissue between our ears (though I have met some whom I am sure have a six
inch stainless steel bar to hold their ears apart).
Each ‘electrical’ neuron has a cell
body (the grey matter) and long, thin extensions called dendrites and axons
(the white matter) that reach out and link to others. Most neurons have
lots of dendrites that receive information from other nerve cells, and one
axon that branches on to other cells and sends information out. On average,
each neuron forms 10,000 connections, through synapses (connections) with
other nerve cells. Altogether, Lichtman estimates there are between 100
trillion and 1000 trillion connections between neurons. That makes the
‘connectome’ study look fairly impossible as far as completion in a human
life span timetable is concerned.
Whilst Lichtman’s study is to be
commended for its thoroughness, there are others in the research field who
claim that this degree of trying to identify all pathways is really too
much. Olaf Sporns, the neuroscientist at Indiana University, who coined the
term ‘connectome’ in 2005 says that, “If you want to study the rainforest,
you don’t need to look at every leaf and every twig and measure its position
and orientation. It’s too much detail.”
Sporns and other neuroscientists are
focusing on what they believe is achievable today, under the $40 million
Human Connectome Project.
One hurdle which must be overcome is
the fact that all our brains are different in many details, though similar
on a large scale. Neuroscientists have some idea of how brains are wired,
but the variability between even healthy people is substantial.
The connectomes mapped out by the
Connectome Project will (hopefully) show scientists what healthy brain
wiring looks like. But is there a difference with dysfunctional brains, in
psychiatric cases, for example?
“'With a lot of psychiatric disorders,
like schizophrenia, drug addiction, obsessive-compulsive disorder and
depression, you can look at a brain scan and there’s nothing you can see
that stands out as an abnormal hotspot on the scan,” Ed Bullmore, a
neuroscientist at Cambridge University, says. That scanning is with the
technology available today, such as MRI investigations.
Adding to the complexity, the cerebral
cortex makes up 80 percent of the human brain, but holds only a fifth of its
neurons. Tucked beneath the cerebral hemispheres, the cerebellar cortex
occupies only a tenth of the brain’s volume but contains 80 percent of its
neurons. Again, even with the naked eye, the brain’s lobes and lobules
differ markedly from person to person.
These differences are vital in trying
to understand the complex workings, and the Connectome Project is studying
twins and their non-twin siblings. The researchers should also come to
Suvarnabhumi airport, as many visitors appear to leave their brains there!
Finally Jeff Lichtman says, “All the
normal functions of the brain, the storage of information about the world,
our memories, the way we perceive the world, the behaviors we learn, are all
probably encoded in connectivity.”
Health food shop for sale
Spotted the following item in the
Classified section: “Health Food Store for sale. Genuine reason for quick
sale. Current owner too ill to continue working.”
OK, perhaps I used a little poetic
license there, but the real situation is the fact that recent studies have
shown that health food supplements give no guarantees of superior health,
and in fact some supplements may even be harmful!
A panel of five experts, led by Dr
Maria Elena Martinez, from the University of California at San Diego, wrote,
“Undoubtedly, use is driven by a common belief that supplements can improve
health and protect against disease, and that at worst, they are harmless.
However, the assumption that any dietary supplement is safe under all
circumstances and in all quantities is no longer empirically reasonable.”
The US scientists said there was no
good evidence that supplement pills and capsules reduced the risk of cancer
in healthy individuals, pointing out that antioxidants such as beta
carotene, and vitamins C and E might even have biological effects that
promote cancer. Now that is certainly not good news for the “anti-oxidant”
One of the biggest problems to be
overcome, from the lay persons point of view, is that they are bombarded
with amazing claims by the health food industry with health supplements
sales estimated at USD 30 billion, said the scientists, who assessed the
evidence relating to several supplements including antioxidants, folic acid,
vitamin D and calcium.
Looking at the well known
anti-oxidants, they are believed to counter the destructive effects of rogue
oxygen molecules called free radicals. Oxidative stress by free radicals,
which attack cell membranes, proteins and DNA, has been linked to cancer and
heart disease. But the US authors, writing in the Journal of the
National Cancer Institute, argue that the supposed benefits of
antioxidant supplements are largely a myth, saying people were misled by
“messages from supplement manufacturers” promoting the health benefits of
their products, including cancer prevention.
Now, conventional medicine is subject
to rigorous testing (though I will admit we do make some mistakes from time
to time) and this is called Evidence Based Medicine, or EBM as we love
Now according to the US studies, some
animal, laboratory and observational studies had appeared to show that
dietary supplements could lower cancer risk; however, those findings were
not confirmed by the “gold-standard” in evidence-based medicine, which
requires randomized controlled trials (RCTs). Only a small number of RCTs
had been carried out to test the effectiveness of dietary supplements, said
the experts - and several of these had reported increased risks.
There are those who will claim that
because the “natural” products come from plants, the ingredients are
therefore OK for us humans. This is pseudo-scientific nonsense. Extracts
of plants and herbs are chemicals - and some chemicals can kill, that is why
wild animals can die after eating the wrong plants. So can you!
Unfortunately, despite all the advances
in conventional medicine, I have to admit that it is still somewhat of an
inexact ‘science’. We do not have the cures for all ailments, in fact far
from it. We continue to try and most importantly, to test. With EBM we
must test until we have the evidence that any drug or treatment really does
work. This all takes time, as the evidence cannot just hang on one person
who got better. It requires huge series, across the globe.
However, as patients, or sufferers of
any complaint, we want that “cure” right now! Consequently, with all
medical conditions where we cannot give the patient the “wonder drug” there
is then a tendency for them to try something else, anything else, hoping for
the relief that conventional medicine has not promised or delivered.
This turning towards alternatives is
then quite easily understood. For the musculo-skeletal conditions, for
example, the “alternatives” are multiple, from magnets to mussels from New
Zealand. But do they really work? According to the pundits, the green
lipped mussels have had numerous clinical trials, and unfortunately, the
same number of clinical failures! However, I believe they are quite nice
steamed with garlic, ginger and shallots!
Consider the evidence before expensive
(Thank you Dr. William for bringing
this item to my attention.)
The Communications Game
As a profession, doctors are
notoriously bad communicators. Patients complain that after seeing their
doctor they come out of the consulting room and have no real idea of what is
wrong with them or what caused the problem.
And that scenario is not just here in
Thailand where either the doctor or the patient is having to speak in a
‘foreign’ language, but is true for Australian patients with their
Australian doctor, and likewise for UK patients with their native English
I was reminded of this the other day,
when a chap with prostate cancer saw me wanting to discuss his medical
situation. “Am I stage 1, stage 2, stage 3 or stage 4?” he asked. He had
plenty of results, had seen local doctors, hospital doctors, cancer hospital
doctors and he was just as much in the dark as he was when first diagnosed.
Of course, staging prostate cancer can
be confusing. The Prostate Specific Antigen levels (PSA) are only a guide.
There is also the simple four stage typing. Then there are other scales
such as the TNM (tumor, node, metastases) and yet another called the Gleason
score. With all those complications it is no wonder patients get confused.
I dealt with prostate cancer a few
months ago, but it is obvious I should touch on the subject again. Firstly,
is prostate cancer rising? Not really. One reason for the ‘apparent’
increase in prostate cancer is the fact that prostate cancer is a disease of
aging, and we are all living longer. The statistics would show that by age
50, almost 50 percent of American men will have microscopic signs of
prostate cancer. By age 75, almost 75 percent of men will have some
cancerous changes in their prostate gland. Do the math. By 100 we’ve all
So does this mean that life really ends
at around 76? Fortunately no. Most of these cancers stay within the
prostate, producing no signs or symptoms, or are so slow-growing, that they
never become a serious threat to health.
While the numbers quoted above look
fearsome, the real situation is not quite so bad. A much smaller number of
men will actually be treated for prostate cancer. About 16 percent of
American men will be diagnosed with prostate cancer during their lives; 8
percent will develop significant symptoms; but only 3 percent will die of
the disease. Put another much more positive way, 97 percent won’t die from
prostate cancer. This means I must be OK, as my three friends with prostate
cancer hopefully make up the three percent of my acquaintances.
However, the great majority of prostate
cancers are slow growing, and it can be decades between the early diagnosis
and the cancer growing large enough to produce symptoms.
So let’s look at diagnosis and get the
“blood test” out of the way first. Unfortunately, PSA is not a go-no go
test. Serial PSA examinations can show the rate of growth, another good
reason for regular check-ups.
Like many other cancers, prostate
cancer can only be fully diagnosed by examining prostate tissue samples
under the microscope. When your doctor suspects prostate cancer on the
basis of your symptoms, or the results of a clever finger rectal examination
(DRE), and/or a PSA test - the definitive diagnosis will need a biopsy.
So let’s imagine that now you have had
a positive biopsy. You’ve got it! What are the real options? Actually
very many and depend mainly upon the ‘stage’ of the cancer and your age at
the time of diagnosis.
Simple ‘Staging’ has four main grades.
Stage I cannot be felt and is diagnosed through pathological testing. Stage
II can be felt, but it is confined to the prostate. Stage III is coming out
of the gland and Stage IV has grown into nearby tissues.
Treatment can be ‘watch and wait’,
surgery, radiation, and hormone therapy.
Watch and wait has much going for it,
but you must be prepared to get to know your urologist on first name terms.
You will be seeing a lot of him over the years, so pick a young one with
good English! Medical communication can be something of a minefield.
How’s the family’s health?
I often write about the value of check-ups, as I am a
firm believer in catching reversible medical conditions before they become
terminal medical conditions. I know we are all going to die one day - even
me, though having been told you can’t take it with you, I have decided I’m
not going! But do you want to spend your final decade incapacitated,
because you didn’t know your blood pressure was so high you ended up with a
stroke? Wheelchairs aren’t all that much fun, they tell me.
As we get older, be prepared for some
“normal” changes. Yes, as your body’s skin gets older, it starts to show
it. It becomes less elastic, folds start to form everywhere, it gets
thinner and tears easily, and small bruises form just below the top layer.
Women try and counteract this aging process with all kinds of creams, but
quite frankly, I think they are wasting their (husbands?) money. You can
rub ‘moisturizing’ cream into the skin as much as you like, it will remain
impervious to water.
Unfortunately, as we get older, this
body of ours tends to become a very high maintenance item. Unless we have
medically planned for our future, we (that’s you) will find that it becomes
an expensive item.
Take for example, your weight. Eating
is fun and pleasurable, but too much of the good thing and you become
overweight. When you are 30 or 40 you can joke about the beer belly, but
when you are 50 and 60 and you have become diabetic and your arteries are
blocked, you are in for some expensive medications for the rest of your
life, some life saving cardiac surgery and you may even need to have your
lower leg amputated.
Another item that we watch changing as
we get older is our blood pressure. The old adage used to be that your
blood pressure should be your own age plus 100. Like many old adages, that
was total nonsense too. A 60 year old man should not ignore a BP (systolic)
of 160. The cardiologists and the kidney specialists will tell you that you
should maintain your BP at around 125/70 for all your life if you don’t want
to have cardiac and renal problems as you get on in years.
One other aging factor that we should
look out for is cancer. We know the majority of cancers develop as we get
older. Should you wait for them to come, and then try to stop the
progression? Stopping the cancer with expensive surgery and even more
expensive chemotherapy, or stop putting ourselves ‘at risk’ in our younger
years? This ‘at risk’ behavior means smoking, of course. Not just for lung
cancer, but for all cancers. The expensive habit of a lifetime becomes a
very expensive end of your lifetime. Why do it? It makes no sense at all.
There is no ‘justification’, I’m sorry.
Unfortunately, our bodies are very much
like our cars. If you look after your transport, have it regularly
serviced, replace the bits that are wearing out before they totally fail and
then damage the rest of the car, then your vehicle will last for many years
and give very close to ‘as new’ performance for as long as you keep it. The
costs involved in that preventive maintenance are very low compared to
having to replace major parts.
Using that analogy on your body, if you
look after it, it can also give you good service. Preventive maintenance by
having regular check-ups makes sense. Look for the warning signs and
correct the problems. You can even screen for ‘cancer markers’ such as
alpha-Fetoprotein (AFP), Carcinoembryonic antigen (CEA), Prostate specific
antigen (PSA), Pap smears and colonoscopies. If you are a young woman you
can even immunize against Human Papilloma Virus.
We do tend to look upon our own health,
but we should also be thoughtful of our partner’s health as well. Get that
check-up, and one for your partner as well. Isn’t it time you gave your
bodies the once-over?