A - SENESCENCE - SENILITY:
represents normal ageing physiological.
represents a pathological rupture of physiological
ageing following accidents which modify normal
EVALUATION OF AGEING:
Ageing is a
whole of consequences of the action of time on the alive
different according to species' and, in the same
species, according to individuals'.
is biologically arbitrary.
make only one analytical approach of it.
resistance and less effectiveness.
reduction in the functional capacities.
one ages, the more one has risks to develop medical
less resistance to the infections.
does not want to say that the immune system is
effectiveness: reduction in the load-carrying capacity
(race, for example).
in the functional capacities: the maximum is reached
around 20 years.
years, the pulmonary capacity reaches approximately 45%
of what it was at 20 years.
function is also maximum at 20 years.
filtration is at 100%.
years, one lost 40% of this capacity.
creatininemy is 40% higher.
MANIFESTATIONS OF AGEING:
ageing for example.
Reduction in the functional capacities
The risk to
develop certain affections is greater.
The risk of
after-effects also increases.
in the risk of mortality
in the capacities of each function.
average longevity in the industrialized countries is
• 82 years
for the women
• 78 years
for the men
The risk of
mortality is primarily due to the heart diseases and
were decreased, one would currently increase the
longevity by 18 years.
CONCEPT OF AGEING PHYSIOLOGICAL:
PRIMARY EDUCATION AGEING:
characteristic of each species.
in the life expectancy:
possibility to traverse our life such as it is
registered according to our species.
Deterioration of the functions according to the
the same species, all the individuals age on the same
• But each
individual will age according to his own
factors of the way of life intervene to modify this
of certain affections (lithiasis example: renal
individual, the functions do not age in the same
risk of death at an old person is the pulmonary
infection, not because the immune system is weakened but
because the pulmonary capacity is reduced.
the renal function: an infection can be enough to cause
an acute renal insufficiency requiring dialysis with all
the consequences which follow.
CHARACTERIZATION Of a DISORDER BINDS TO PRIMARY
necessary that this disorder is:
Endogenous: not caused by an accident
Universal: corresponding to the normal ageing of the
BIOLOGICAL CHARACTER OF AGEING:
REDUCTION IN THE NUMBER OF CELLS:
Present at the level of all the bodies:
explain largest occurred of cancers.
an atrophy of the bodies:
crystalline lens starts to age as from 12 years.
Development of fabric of replacement:
Substitution of fabric of involving support for
other fabrics of the consequences on the level of
circulation: less vascularized fabric.
involves a reduction in the thin mass which constitutes
primarily the muscles.
INCREASE IN THE FATTY MASS:
is the thin mass which ensures the performances.
THEORIES OF AGEING:
THEORY OF AGEING PROGRAMS:
according to which ageing is under the dependence of a
would start our ageing.
however that our ageing obeys a biological clock.
this progression the possible biological accidents come
apoptose is synonymous with cellular death.
cellular clone has a capacity of 120 divisions.
certain number of factors will intervene to decrease the
number and to accelerate the rate/rhythm of these
THEORY OF THE FREE RADICALS:
which makes it possible to detect precociously occurred
of cancers in particular.
accumulation of errors in the reproduction of the cells
would have a mutagen action.
cellular renewal would be made in an erroneous way, upon
an attack, tissue, cellular, molecular, the reproduction
is followed on the basis of genetic inheritance.
highlighted the presence of genes which represented a
pejorative factor on occurred of cancers.
which develops generally knew 2 to 3 years of evolution
before being expressed.
A - PHYSIOLOGY:
manifestations of ageing:
of the neuronal cells:
We are born
with a definite neuronal stock.
cellular ageing, we regularly lose these cells as of the
in the weight of the brain.
development of an insanity can involve a loss from 40 to
50% of the weight of the brain.
of the cortical furrows:
which represented a virtual space widen, giving place to
a real space.
of space interventriculaire:
interventriculaire secretes the céphalo-rachidian liquid
at a rate of 2 ml/h.
widening of this space will involve a stagnation of the
cause an increase in the pressure and a phenomenon of
with the scanner.
must be the subject of a treatment.
Can lead to
severity of the irrational state is closely dependent on
the number of the lesions and their seat.
demonstrations appear when the lesions reach the
peripheral part of the cortex.
• With the
lower part of 5% of the lesions: no
• Between 5
and 7% beginning of the risk
10%, the irrational state is inescapable
Deterioration of dendrites which puts 5 to 6
years, even 7, to constitute itself without there being
dendrites are reached, the process is inexorable.
the cellular body.
functions by the production of neurotransmitters.
thought for example that the depression is under the
dependence of 2 neurotransmitters:
of Alzheimer or degenerative insanity:
Acetylcholine: cholinergic system
symptoms are directly related toits rate: the lower it
is, the more the symptoms are violent one.
modification of the behavior in depressive form can hide
the first steps of an insanity.
tracking of the evolution of an irrational problem is
treatments can operate only existing neurons.
precocity of the treatment is determining.
Beyond of a
year of evolution, the things are generally
neurotransmitter is synthesized and destroyed.
the enzymes which destroy neurotransmitter one increases
its lifespan and thus its action.
evolution from 5 to 6 years.
of the short-term memory and recent.
Conservation of the old memory
of the orientation temporo-spaciale
of the judgement: absurd acts, loss of
difficulties, but the patient is not aphasic
of the motor and gnostic functions
of the primitive functions: mood, abulia (food
treatment can only delay the evolution during
approximately 5 years.
considers new molecules which will give 10 years of
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