We can now try to
elaborate upon the science of these syndromes, realising that this is
work in progress.
We will now proceed
to look in some detail at elements that need understanding so that we
can look at the patterns that connect them.
This is written
with more technical data than I first intended.
From time to time
I will try to summarize the crucial information.
IDENTIFYING ABNORMALITIES
AND EXPLAINING MECHANISMS.
Here we are operating
in medical models, drawing upon scientific methods.
This chapter is
largely about genes and viruses.
The most likely
explanations relate to the following factors:
Genetic vulnerability.
It would be difficult to adequately describe the range of gene research
which is being undertaken in this early part of the 21st century, but
I want to mention the following,
Genes, which shape
gene products such as functional protein and enzyme activity levels.
These include genes,
which for example shape lipid profiles.
Some specific genes
shape immune responses.
(e.g.MHC genes commonly
described as HLA, genes which code for cytokines and for their receptors
and probably an array of genetic polymorphisms relating to substances
in cascades of events along complex immune pathways.)
Genes have times
of being activated such that their products come into action.
Germ cell DNA in
the ovum and sperm carries information from one generation to the next.
In somatic cells
the genes carry out their functions in every nucleated cell.
Somatic mutations
in these cells can have minor or major, as well as short term or long
term consequences for those cells and for the whole organism.
The ongoing work
on the complete human genome is already bearing fruit in very many diseases.
Human beings have
about 24,000 genes which code for protein synthesis.
These genes may
have tens of thousands to hundreds of thousands of base sequences.
Through the existence
of spliceosomes, genes can code for more than one protein.
Major Histocompatibility
Complex
Study of HLA and
major histocompatibility complex (MHC) molecules, is revealing intriguing
links with specific disorders.
The term histocompatibility
arose in the context of grafts (and acceptance or rejection) between
members of a species.
By international
agreement HLA is the logo for human MHC.
MHC can be used
as a term to cover the genes and gene products.
The MHC genes are
located on the short arm of chromosome 6.
Class I molecules
are expressed on virtually all cell surfaces and are products of 3
reduplicated loci: HLA-A, HLA-B and HLA-C.
Class II molecules
are restricted in expression to B-lymphocytes, dendritic cells, macrophages,
monocytes, antigen-activated T lymphocytes, and to epithelial and
endothelial cells that have been activated by interferon. They are
products of closely linked genes in the HLA-D region.
Class III molecules
are the C4, C2 and Bf components of complement.
Complement is a
cascading series of plasma enzymes, regulatory proteins and proteins
capable of cell lysis. Complement activity is involved in the opsonization
of bacteria, and some fractions are potent mediators of immune cell
activation (e.g. C5a is a potent chemo attractant for neutrophils and
monocyte-macrophages.)
I will expand on
the immunological mechanisms in later chapters..
One illustration
is the discovery that four environmental exposures may increase the
emergence of type1diabetes in people possessing certain HLA haplotypes.
These are exposures
to
(1) Certain coxsackie
B viruses,
(2) Beta casein
A1 from cow’s milk,
(3) Exposure to
cereals such as wheat (this latter at specific times of development
such as before 4 months of age)
(4) Vitamin D
deficiency during pregnancy
Environmental
stress.
Chemicals including pesticides, industrial products, intoxicants and
anaesthetics may cause severe, moderate or subtle effects on cellular
chemistry especially contributing to cell membrane abnormalities in
mitochondria. These changes may be evident quickly or may not emerge
or be detected for months, years or even decades.
DNA itself is susceptible
to injury, particularly in rapidly dividing cells.
Many experts suggest
that injury to mitochondria is important.
Mitochondria are
the cytoplasmic organelles, which provide 80% of the energy of eukaryotic
cells.
The mitochondrial
DNA is 10 times more susceptible to mutation than nuclear DNA, and mitochondrial
membranes are susceptible to oxidative injury.
One thing that appears
to be protective of nuclear DNA is the time it rests in a folded form
in between times of cell replication.
There is some evidence
that immune responses can be suboptimal in mammalian cells when pesticides
and some industrial products are present in very low concentrations.
Yet other environmental
chemicals appear to be hormone disrupters (eg oestrogen disrupters)
or diverters of steroid hormones into unwanted pathways.
This is pertinent
to recent and long-standing controversies such as hormone replacement
therapies.
There are reasons
to be alarmed about the extensive exposure of all living systems on
the earth to these chemicals!
This requires us
to ask all industries and their support systems, to act for all of the
people on the earth, rather than just for their shareholders.
A transparency and
honesty, which has been hitherto unknown on earth, is needed.
Scientists, who
are beholden to multinational or national corporate organizations, could
blaze a trail of friendship to knowledge and commitment to integrity
to bring about a new and healing era of our earth.
David Suzuki has
blazed a trail in creating and maintaining awareness of ecology.
PATHOGENS
At the beginning
of the following material on micro-organisms, I remind the reader that
we are looking at the earliest forms of life, including their evolution
and genetics, and sometimes, living pieces which have emerged such as
viruses.
The first forms
of life are likely to be primitive bacteria, which emerged on the earth
some 3.8 billion years ago.
All organisms which
have arisen since, live in the presence of and interact with the organisms
called prokaryotes.
In chapters to come,
I will elaborate on prokaryotes.
Celera, the private
team that completed the human genome project, describe the genome as
a dynamic and vibrant ecosystem.
This lifestyle diversity
owes itself to the ability to trade RNA and DNA.
Elisabet Sahtouris
writes” To this day, every bacterium on this planet can trade bits
of DNA with any other it can contact.”
What an amazing
contribution to our understanding of evolution!
Although I refer
to pathogens (disease causing agents), I am attentive to the potential
for organisms to give rise to certain kinds of injury in the host, albeit
as a survival mechanism for themselves, or to coexist in a non-damaging
way.
Micro-organisms
may evolve into complementary and benign roles and are probably essential
to many ecological balances.
In a strange way,
some organisms are pathogens for a time, or to some creature, or to
particular people, but not to others.
In the chapters
to follow I will discuss viruses, bacteria and other infective organisms.
