|
Vaccinazioni per l’infanzia ed
autismo
Metalli tossici
dei vaccini = Autismo vedi: PDF - dott.
M. Proietti
Sentenza 2012 - Trib. Rimini su
Vaccini=Autismo
Commento NdR: sulla sentenza di Rimini: vaccini =
autismo
BENE ha
fatto il Giudice del Tribunale di Rimini (Italia) a
sentenziare in quel modo, perche' egli non si e'
lasciato influenzare dalle FALSITA' del Ministero della "salute" (che e'
stato da noi
informato sui Danni dei vaccini dal 1996 e
se ne sta zitto.....assieme a
tutti gli altri "enti"....) fino agli ordini
dei medici......tutti al servizio di
Big Pharma !
- vedi lo studio del dott.:
Wakefield.htm
In CINA dopo le campagne vaccinali esplode
l'Autismo ! - Maggio 2016
http://yournewswire.com/autism-rates-explode-in-asia-after-introducing-western-vaccines/
VERISSIMO, ma non solo l'autismo....ma una
innumerevole sequela di altre
malattie....
Autismo
e non solo dai Vaccini:
USA, Giugno 2013 - AUTISMO = 1 bambino
autistico su 26, non come era nel 2010, 1
su 80 ....
vedi QUI:
http://autismovaccini.com/2012/05/01/statistiche-per-lautismo-a-confronto-probabile-1-ogni-29-anziche-1-ogni-88/
Ricordo che,
molta importanza hanno anche i cibi assunti non
adatti al gruppo sanguigno del soggetto.
I Tribunali anche USA, confermano tranquillamente che il
vaccino
MMR causa l'autismo. Austin (USA) - 27 Luglio 2013
Dopo decenni di appassionato dibattito, per i genitori che
probabilmente hanno perso i ripetuti ricorsi richiesti dalle
aziende farmaceutiche e governi, che i vaccini infatti causano
l'autismo.
Per i genitori interessati alla ricerca della verità, vale la
pena ricordare che le stesse persone che possiedono le aziende
farmaceutiche di tutto il mondo possono anche possedere agenzie
di stampa americane.
La Ricerca di informazioni prive di propaganda è stata fino ad
ora molto difficile.
Ma Whiteout Press non è qui per sostenere o contrastare i
vaccini. Siamo qui per portare i lettori la notizia che è il
tema e’ in black-out, cover-up e censurato dalle autorita’Sanitarie
e Governative.
Tratto da:
http://www.whiteoutpress.com/timeless/courts-quietly-confirm-mmr-vaccine-causes-autism/
La prova della FRODE del
CDC
per le cause dei
Vaccini
nell'Autismo
- CONFESSIONE di un alto dirigente
CDC, davanti al Congresso US
Gli esperti di
vaccini
del
CDC, hanno spesso
conflitti di
interesse
- 18/03/2010
CDC e
Conflitti di interesse - 1
+
CDC e Conflitti
di interesse - 2
+
CDC e Conflitti
di interesse - 3
+
Corruzione
+
Danni dei
Vaccini +
Contro Immunizzazione
CDC
conflitti di
interesse
anche per i vaccini +
anche per la FDA
http://healthimpactnews.com/2014/cdcs-purchase-of-4-billion-of-vaccines-a-conflict-of-interest-in-overseeing-vaccine-safety/
Davvero inquietante !
Questo medico il Dott.
Andrew Moulden è MORTO (probabilmente
assassinato) in modo inspiegabile nel
novembre 2013 al età di 49, subito dopo
aver pubblicato Le SUE RICERCHE che
DIMOSTRANO il DANNO CAUSATO dai VACCINI,
RICONOSCIBILI SOLO da un SEMPLICE ESAME
ESTERNO
http://vaccineimpact.com/2015/dr-andrew-moulden-learning-to-identify-vaccine-damage/
Parlamentari pagati dalle Lobbies ? -
Roma Ott. 2013
L'intervista a un assistente di un Senatore
che svelerebbe i traffici illeciti tra
parlamentari e
Lobbies.
Video dell'intervista:
http://www.video.mediaset.it/video/iene/puntata/390060/roma-parlamentari-pagati-dalle-lobbies.html
Informatore dei
CDC
CONFESSA la FRODE e le FALSIFICAZIONI sugli
studi della correlazione VACCINO=AUTISMO
II.
COMPARISON OF BIOLOGICAL ABNORMALITIES
Like
the similarities seen in observable symptoms, parallels between autism
and mercury poisoning clearly exist even at cellular and subcellular
levels. These similarities are summarized in tables after each
individual section.
a. Biochemistry
Sulfur:
Studies of autistic children with known chemical or food
intolerances show a low capacity to oxidize sulfur compounds and low
levels of sulfate (O’Reilly & Waring, 1993; Alberti et al, 1999). These findings were interpreted as suggesting that “there
may be a fault either in the manufacture of sulfate or that sulfate is
being used up dramatically on an unknown toxic substance these children
may be producing” (O'Reilly and Waring, 1993).
Alternatively, these observations may be linked to mercury, since
mercury preferentially forms compounds with molecules rich in sulfhydryl
groups (--SH), such as cysteine and glutathione,making them unavailable
for normal cellular and enzymatic functions (Clarkson, 1992). Relatedly,
mercury may cause low sulfate by its ability to irreversibly inhibit the
sulfate transporter Na-Si cotransporter NaSi-1 present in kidneys and
intestines, thus preventing sulfate absorption (Markovitch and Knight,
1998).
Among
the sulfhydryl groups, or thiols, mercury has special affinity for
purines and pyrimidines, as well as other subcellular substances
(Clarkson, 1992; Koos and Longo, 1976).
Errors in purine or pyrimidine metabolism are known to result in
classical autism or autistic features in some cases (Gillberg and
Coleman, 1992, p.209; Page et al, 1997; Page & Coleman, 2000; The
Purine Research Society), thereby suggesting that mercury’s disruption
of this pathway might also lead to autistic traits.
Likewise, yeast strains sensitive to Hg are those which have
innately low levels of tyrosine synthesis.
Mercury can deplete cellular tyrosine by binding to
the SH-groups of the tyrosine uptake system, preventing
colony growth (Ono et al, 1987), and Hg-depleted tyrosine
would be particularly significant in cells known to
accumulate mercury (e.g., neurons of the CNS, see below).
Similarly, disruptions in tyrosine production in
hepatic cells, arising from a genetic condition called
Phenylketonuria (PKU), also results in autism (Gillberg &
Coleman, 1992, p.203).
Glutathione:
Glutathione is one of the primary meansthrough which
the cells detoxify heavy metals (Fuchs et al, 1997), and
glutathione in the liver is a primary substrate by which
body clearance of organic mercury takes place (Clarkson,
1992). Mercury,
by preferentially binding with glutathione and/or preventing
absorption of sulfate, reduces glutathione bioavailability.
Many autistic subjects have low levels of
glutathione.
O’Reilly and Waring (1993) suggest this is due to an
“exotoxin” binding glutathione so it is unavailable for
normal biological processes.
Edelson and Cantor (1998) have found a decreased ability of
the liver in autistic subjects to detoxify heavy metals.
Alternatively, low glutathione can be a manifestation
of chronic infection (Aukrust et al, 1996, 1995; Jaffe et
al, 1993), and infection-induced glutathione deficiency
would be more likely in the presence of immune impairments
derived from mercury (Shenkar et al, 1998).
Glutathione peroxidase activities were reported to be
abnormal in the erythrocytes of autistic children (Golse et
al, 1978).
Mercury generates reactive oxygen species (ROS)
levels in cells, which increases ROS scavenger enzyme
content and thus glutathione, to relieve oxidative stress (Hussain
et al, 1999).
At high enough levels, mercury depletes rat
hepatocytes of glutathione (GSH) and causes significant
reduction in glutathione peroxidase and glutathione
reductase (Ashour et al, 1993).
Mitochondria:
Disturbances of brain energy metabolism have prompted autism
to be hypothesized as a mitochondrial disorder (Lombard,
1998).
There is a frequent association of lactic acidosis
and carnitine deficiency in autistic patients, which
suggests excessive nitric oxide production in mitochondria
(Lombard, 1998; Chugani et al, 1999), and again, mercury may
be a participant.
Methylmercury accumulates in mitochondria, where it
inhibits several mitochondrial enzymes, reduces ATP
production and Ca2+ buffering capacity, and disrupts
mitochondrial respiration and oxidative phosphorylation
(Atchison & Hare, 1994; Rajanna and Hobson, 1985; Faro et
al, 1998).
Neurons have increased numbers of mitochondria (Fuchs et al,
1997), and since Hg accumulates in neurons of the CNS, an Hg
effect upon neuronal mitochondria function seems likely -
especially in children having substandard mercury
detoxification.
|
Table
XI: Abnormalities in Biochemistry Arising
from Hg Exposure & Present in Autism
|
| Mercury |
Autism |
| Ties
up sulfur groups; prevents sulfate absorption |
Low
sulfate levels |
| Has
special affinity for purines and pyrimidines |
Errors
in purine and
pyrimidine metabolism can lead to autistic features |
| Depletes
cellular tyrosine in yeast |
PKU,
arising from disruption in tyrosine production, results in autism |
| Reduces
bioavailability of glutathione, necessary in cells and liver for
heavy metal detoxification |
Low
levels of glutathione; decreased ability of liver to detoxify
heavy metals |
| Can
cause significant reduction in
glutathione peroxidase and glutathione reductase |
Abnormal
glutathione peroxidase activities in erythrocytes |
| Disrupts
mitochondrial activities, especially in brain |
Mitochondrial
dysfunction, especially in brain |
b. Immune System
A
variety of immune alterations are found in autism-spectrum children (Singh
et al, 1993;Gupta et al, 1996; Warren et al, 1986 & 1996; Plioplys et
al, 1994), and these appear to be etiologically significant in a variety
of ways, ranging from autoimmunity to infections and vaccination responses
(e.g., Fudenberg, 1996; Stubbs, 1976).
Mercury’s effects upon immune cell function are well documented
and may be due in part to the ability of Hg to reduce the bioavailability
of sulfur compounds:
“It has been
known for a long time that thiols are required for optimal primary in
vitro antibody response, cytotoxicity, and proliferative response to
T-cell mitogens of murine lymphoid cell cultures.
Glutathione and cysteine are essential components of lymphocyte
activation, and their depletion may result in lymphocyte dysfunction.
Decreasing glutathionelevels profoundly affects early signal
transduction events in human T-cells” (Fuchs & Schöfer, 1997).
Allergy,
asthma, and arthritis:
Individuals with autism are more likely to have allergies and
asthma, and autism occurs at a higher than expected rate in families with
a history of autoimmune diseases such as rheumatoid arthritis and
hypothyroidism (Comi and Zimmerman, 1999; Whitely et al, 1998).
Relative to the general population, prevalence of selective IgA
deficiency has been found in autism (Warren et al); individuals with
selective IgA deficiency are more prone to allergies and autoimmunity
(Gupta et al, 1996). Furthermore,
lymphocyte subsets of autistic subjects show enhanced expression of HLA-DR
antigens and an absence of interleuken-2 receptors,and these findings are
associated with autoimmune diseases like rheumatoid arthritis (Warren et
al). These observations suggest autoimmune processes are present
in ASD (Plioplys, 1989; Warren et al); and this possibility is reinforced
by Singh’s findings of elevated antibodies against myelin-basic protein
(Singh et al, 1993).
Atypical
responses to mercury have been ascribed to allergic or autoimmune
reactions (Gosselin et al, 1984; Fournier et al, 1988), and genetic
predisposition for Hg reaction may explain why sensitivity to this metal
varies so widely by individual (Rohyans et al, 1984; Nielsen &
Hultman, 1999). Acrodynia can
present as a hypersensitivity reaction (Pfab et al, 1996),
or it may arise from immune over-reactivity, and “children
who incline to allergic reactions have an increased
tendency to develop acrodynia” (Warkany & Hubbard, 1953).
Those with acrodynia are also more likely to suffer from
asthma, to have poor immune system function (Farnesworth,
1997), and to experience intense joint pains suggestive of
rheumatism (Clarkson, 1997).
Methylmercury has altered thyroid function in rats
(Kabuto, 1991).
Rheumatoid arthritis with
joint pain has been observed as a familial trait in autism
(Zimmerman et al, 1993).
A subset of autistic subjects had a higher rate of
strep throat and elevated levels of B lymphocyte antigen
D8/17, which has expanded expression in rheumatic fever
and may be implicated in obsessive-compulsive behaviors (DelGiudice-Asch
& Hollander, 1997).
Mercury exposure frequently results in rheumatoid-like
symptoms.
Iraqi mothers and children developed muscle and
joint pain (Amin-Zaki, 1979), and acrodynia is marked by
joint pain (Farnesworth, 1997).
Sore throat is occasionally a presenting sign in mercury
poisoning (Vroom and Greer, 1972). A 12 year old with
mercury vapor poisoning, for example, had joint pains as
well as a sore throat; she was positive on a streptozyme
test, and a diagnosis of rheumatic fever was made; she
improved on penicillin (Fagala and Wigg, 1992). Acrodynia, which is almost never seen in adults, was also
observed in a 20 year old male with a history of
sensitivity reactions and rheumatoid-like arthritis, who
received ethylmercury via injection in gammaglobulin
(Matheson et al, 1980).
One effective chelating agent, penicillamine, is
also effective for rheumatoid arthritis (Florentine and
Sanfilippo, 1991).
Mercury can induce an autoimmune response in mice and
rats, and the response is both dose-dependent and
genetically determined.
Mice “genetically prone to develop spontaneous
autoimmune diseases [are] highly susceptible to
mercury-induced immunopathological alterations” (al-Balaghi,
1996).
The autoimmune response depends on the H-2
haplotype:
if the strain of mice does not have the
susceptibility haplotype, there is no autoimmune response;
the most sensitive strains show elevated antibody titres
at the lowest dose; and the less susceptible strain
responds only at a medium dose (Nielsen & Hultman, 1999).
Interestingly, Hu et al (1997) were able to induce
a high proliferative response in lymphocytes from even low
responder mouse strains by washing away excess mercury
after pre-treatment, while chronic exposure to mercury
induced a response only in high-responder strains.
Autoimmunity and neuronal proteins:
Based upon research and clinical findings, Singh
has been suggesting for some time an autoimmune component
in autism (Singh, Fudenberg et al, 1988).
The presence of elevated serum IgG “may suggest the
presence of persistent antigenic stimulation” (Gupta et
al, 1996).
Connolly and colleagues (1999) report higher rates
in autistic vs. control groups of elevated antinuclear
antibody (ANA) titers, as well as presence of IgG and IgM
antibodies to brain endothelial cells.
On the one
hand,since mercury remains in the brain for years after exposure,
autism’s persistent symptoms may be due to an on-going autoimmune
response to mercury remaining in the brain; on the other hand, activation
and continuation of an autoimmune response does not require the continuous
presence of mercury ions: in fact, once induced, autoimmune processes in
the CNS might remain exacerbated because removal of mercury after an
initial exposure can induce a greater proliferative response in
lymphocytes than can persistent Hg exposure (Hu et al, 1997).
In sera of male
workers exposed to mercury, autoantibodies (primarily IgG) to neuronal
cytoskeletal proteins, neurofilaments (NFs), and myelin basic protein
(MBP) were prevalent. These
findings were confirmed in rats and mice, and there were significant
correlations between IgG titers and subclinical deficits in sensorimotor
function. These findings
suggest that peripheral autoantibodies to neuronal proteins are predictive
of neurotoxicity, since histopathological findings were associated with
CNS and PNS damage. There was
also evidence of astrogliosis (indicative of neuronal CNS damage) and the
presence of IgG concentrated along the bbb (El-Fawal et al, 1999).
Autoimmune response to mercury has also been shown by the transient
presence of antinuclear antibodies (ANA) and antinucleolar antibodies
(ANolA) (Nielsen & Hultman, 1999; Hu et al, 1997; Fagala and Wigg,
1992).
A high incidence of
anti-cerebellar immunoreactivity which was both IgG and IgM in nature has
been found in autism, and there is a higher frequency of circulating
antibodies directed against neuronal antigens in autism as compared to
controls (Plioplys, 1989; Connolly et al, 1999).
Furthermore, Singh and colleagues have found that 50% to 60% of
autistic subjects tested positive for the myelin basic protein antibodies
(1993) and have hypothesized that autoimmune responses are related to an
increase in select cytokines and to elevated serotonin levels in the blood
(Singh, 1996; Singh, 1997). Weitzman
et al(1982) have also found evidence of reactivity to MBP in autistic
subjects but none in controls.
Since
anti-cerebellar antibodies have been detected in autistic blood samples,
ongoing damage may arise as these antibodies find and react with neural
antigens, thus creating autoimmune processes possibly producing symptoms
such as ataxia and tremor. Relatedly,
the cellular damage to Purkinje and granule cells noted in autism (see
below) may be mediated or exacerbated by antibodies formed in response to
neuronal injury (Zimmerman et al, 1993).
T-cells,
monocytes, and natural killer cells:
Many autistics have skewed immune-cell subsets and abnormal T-cell
function, including decreased responses to T-cell mitogins (Warren et al,
1986; Gupta et al, 1996). One recent study reported increased neopterin levels in urine
of autistic children, indicating activation of the cellular immune system
(Messahel et al, 1998).
Workers exposed
to Hgo
exhibit diminished capacity to produce the cytokines TNF (alpha) and IL-1
released by monocytes and macrophages (Shenkar et al, 1998).
Both high dose and chronic low-level mercury exposure kills
lymphocytes, T-cells, and monocytes in humans.
This occurs by apoptosis due to perturbation of mitochondrial
dysfunction. At low, chronic
doses, the depressed immune function may appear asymptomatic, without
overt signs of immunotoxicity. Methylmercury
exposure would be especially harmful in individuals with already
suppressed immune systems (Shenker et al, 1998).
Mercury increases cytosolic free calcium levels [Ca2+]i in T
lymphocytes, and can cause membrane damage at longer incubation times (Tan
et al, 1993).
Hg has also
been found to cause chromosomal aberrations in human lymphocytes, even at
concentrations below those causing overt poisoning (Shenkar et al, 1998;
Joselow et al, 1972), and to inhibit rodent lymphocyte proliferation and
function in vitro.
Depending on
genetic predisposition, mercury causes activation of the immune system,
especially Th2 subsets, in susceptible mouse strains (Johansson et al,
1998; Bagenstose et al, 1999; Hu et al, 1999).
Many autistic children have an immune portrait shifted in the Th2
direction and have abnormal CD4/CD8 ratios (Gupta et al, 1998; Plioplys,
1989). This may contribute to
the fact that many ASD children have persistent or recurrent fungal
infections (Romani, 1999).
Many autistic
children have reduced natural killer cell function (Warren et al, 1987;
Gupta etal, 1996), and many have a sulfation deficiency (Alberti, 1999).
Mercury reduces --SH group/sulfate availability, and this has
immunological ramifications. As
noted previously, decreased levels of glutathione, observed in autistic
and mercury poisoned populations, are associated with impaired immunity
(Aukrust et al, 1995 and 1996;
Fuchs and Schöfer, 1997).
Decreases in NK T-cell activity have in fact been detected in
animals after methylmercury exposure (Ilback, 1991).
Singh detected
elevated IL-12 and IFNg in the plasma of autistic subjects (1996). Chronic
mercury exposure induces IFNg and IL-2 production in mice, while
intermittent presence of mercury suppresses IFNg and enhances IL-4
production (Hu et al, 1997). Interferon
gamma (IFNg) is crucial to many immune processes and is released by T
lymphocytes and NK cells, for example, in response to chemical mitogens
and infection; sulfate
participates in IFNg release, and “the effector phase of cytotoxic
T-cell response and IL-2-dependent functions is inhibited by even a
partial depletion of the intracellular glutathione pool” (Fuchs &
Schöfer, 1997). A
mercury-induced sulfation problem might, therefore, impair responses to
viral (and other) infections - via disrupting cell-mediated immunity as
well asby impairing NK function (Benito et al, 1998).
In animals, Hg exposure has led to decreases in production of
antibody-producing cells and in antibody titres in response to inoculation
with immune-stimulating agents (EPA, 1997, review, p.3-84).
|
Table
XII: Summary of Immune System Abnormalities
in
Mercury Exposure & Autism
|
| Mercury |
Autism |
| Individual
sensitivity due to allergic or autoimmune reactions; sensitive
individuals more likely to have allergies and asthma,
autoimmune-like symptoms, especially rheumatoid-like ones |
More
likely to have allergies and asthma; familial presence of autoimmune
diseases, especially rheumatoid arthritis; IgA deficiencies |
| Can
produce an immune response, even at low levels; can remain in CNS
for years |
Indications
of on-going immune response in CNS |
| Presence
of autoantibodies (IgG) to neuronal cytoskeletal proteins,
neurofilaments, and myelin basic protein; astrogliosis; transient
ANA and AnolA |
Presence
of autoantibodies (IgG and IgM) to cerebellar cells, myelin basis
protein |
| Causes
overproduction of Th2 subset; diminishes capacity to produce
TNF(alpha) and IL-1; kills lymphocytes, T-cells, and monocytes;
inhibits lymphocyte production; decreases NK T-cell activity; may
induce or suppress IFN(gamma) and IL-2 production |
Skewed
immune-cell subset in the Th2 direction and abnormal CD4/CD8 ratios;
decreased responses to T-cell mitogens; increased neopterin; reduced
NK T-cell function; increased IFN(gamma) and IL-12 |
c. CNS Structure
Autism
is primarily a neurological disorder (Minshew, 1996), and mercury
preferentially targets nerve cells and nerve fibers (Koos and Longo,
1976). Experimentally,
primates have the highest levels in the brain relative to other organs
(Clarkson, 1992). Methylmercury
easily crosses the blood-brain barrier by binding with cysteine to form
a molecule that is nearly identical to methionine.
This molecule - methylmercury cysteine - is transported on the
Large Neutral Amino Acid across the bbb (Clarkson, 1992).
Once
in the CNS, organic mercury is converted to the inorganic form (Vahter
et al, 1994). Inorganic mercury is unable to cross back out of the bbb
(Pedersen et al, 1999) and is more likely than the organic form to
induce an autoimmune response (Hultman and Hansson-Georgiadis, 1999).
Furthermore, although most cells respond to mercurial injury by
modulating levels of glutathione, metallothionein, hemoxygenase, and
other stress proteins, “with few exceptions, neurons appear to be
markedly deficient in these responses” and thus more prone to injury
and less able to remove the metal (Sarafian et al, 1996).
While
damage has been observed in a number of brain areas in autism, many
functions are spared (Dawson, 1996).
In mercury exposure, damage is also selective (Ikeda et al, 1999;
Clarkson, 1992), and the list of Hg-affected areas is remarkably similar
to the neuroanatomy of autism.
Cerebellum, Cerebral Cortex, &
Brainstem: Autopsy studies of carefully
selected autistic individuals revealed cellular changes in cerebellar
Purkinje and granule cells (Bauman and Kemper, 1988; Ritvo
et al, 1986). MRI
studies by Courchesne and colleagues (1988; reviewed in ARI Newslett,
1994) described cerebellar defects in autistic subjects, including
smaller vermal lobules VI and VII and volume loss in the parietal lobes.
The defects werepresent independently of IQ.
“No other part of the nervous system has been shown to be so
consistently abnormal in autism.”
Courchesne (1989) notes that the only neurobiological abnormality
known to precede the onset of autistic symptomatology is Purkinje neuron
loss in the cerebellum.
Piven
found abnormalities in the cerebral cortex in seven of 13
high-functioning autistic adults using MRI (1990).
Although more recent studies have called attention to amygdaloid
and temporal lobe irregularities in autism (see below), and cerebellar
defects have not been found in all ASD subjects studied (Bailey et al,
1996), the fact remains that many and perhaps most autistic children
have structural irregularities within the cerebellum.
Mercury
can induce cellular degeneration within the cerebral cortex and leads to
similar processes within granule and Purkinje cells of the cerebellum
(Koos and Longo, 1976; Faro et al, 1998; Clarkson, 1992; see also
Anuradha, 1998; Magos et al, 1985). Furthermore, cerebellar damage
isimplicated in alterations of coordination, balance, tremors, and
sensations (Davis et al, 1994; Tokuomi et al, 1982), and these findings
are consistent with Hg-induced disruption in cerebellar synaptic
transmission between parallel fibers or climbing fibers and Purkinje
cells (Yuan & Atchison, 1999).
MRI studies have documented Hg-effects within visual and sensory
cortices, and these findings too are consistent with the observed
sensory impairments in victims of mercury poisoning (Clarkson, 1992;
Tokuomi et al, 1982). Acrodynia, a syndrome with symptoms similar to autistic
traits, is considered a pathology mainly of the CNS arising from
degeneration of the cerebral and cerebellar cortex (Matheson et al,
1980). In monkeys, mercury preferentially accumulated in the deepest
pyramidal cells and fiber systems.
Mercury
causes oxidative stress in neurons.
The CNS cells primarily affected are those which are unable to
produce high levels of protective metallothionein and glutathione.
These substances tend to inhibit lipid peroxidation and thereby
suppress mercury toxicity (Fukino et al, 1984).
Importantly, granule and Purkinje cells have increased risk for
mercury toxicity because they produce low levels of these protective
substances (Ikeda et al, 1999; Li et al, 1996).
Naturally low production of glutathione, when combined with
mercury’s ability to deplete usable glutathione reserves, provides a
mechanism whereby mercury is difficult to clear from the cerebellum --
and this is all the more significant because glutathione is a primary
detoxicant in brain (Fuchs et al, 1997).
Mercury’s
induction of cerebellar deterioration is not restricted to high-doses.
Micromolar doses of methylmercury cause apoptosis of developing
cerebellar granule cells by antagonizing insulin-like growth factor
(IGF-I) and increasing expression of the transcription factor c-Jun
(Bulleit and Cui, 1998).
Several
researchers have found evidence of a brainstem defect in a subset of
autistic subjects (Hashimoto et al, 1992 and 1995; McClelland et al,
1985); and MRI studies have revealed brainstem damage in a few cases of
mercury poisoning (Davis et al, 1994).
The peripheral polyneuropathy examined in Iraqi victims was
believed to have resulted from brain stem damage (Von Burg and Rustam,
1974).
Amygdala & Hippocampus:
Atypicalities in other brain areas are remarkably similar in ASD and
mercury poisoning. Pathology
affecting the temporal lobe, particularly the amygdala, hippocampus, and
connected areas, is seen in autistic patients and is characterized by
increased cell density and reduced neuronal size (Abell et al, 1999;
Hoon and Riess, 1992; Otsuka, 1999; Kates et al, 1998; Bauman and
Kemper, 1985).
The basal
ganglia also show lesions in some cases (Sears, 1999), including
decreased bloodflow (Ryu et al, 1999).
Mercury
can accumulate in the hippocampus and amygdala, as well as the striatum
and spinal chord (Faro et al, 1998; Lorscheider et al, 1995; Larkfors et
al, 1991). One study has
shown that areas of hippocampal damage from Hg were those which were
unable to synthesize glutathione (Li et al, 1996).
A 1994 study in primates found that mercury accumulates in the
hippocampus and amygdala, particularly the pyramidal cells, of adults
and offspring exposed prenatally (Warfvinge et al, 1994).
The
documenting of temporal lobe mercury provides a direct link between
autism and mercury because, as cited previously, (i) mercury alters
neuronal function, and (ii) the temporal lobe, and the amygdala in
particular, are strongly implicated in autism (e.g., Aylward et al,
1999; Bachevalier, 1994; Baron-Cohen, 1999; Bauman & Kemper, 1985;
Kates et al, 1998; Nowell et al, 1990; Warfvinge et al, 1994).
Bachevalier (1996) has shown that infant monkeys with early
damage to the amygdaloid complex exhibitmany autistic behaviors,
including social avoidance, blank expression, lack of eye contact and
play posturing, and motor stereotypies.
Hippocampal lesions, when combined with amygdaloid damage,
increases the severity of symptoms.
Also
noteworthy is the fact that amygdala findings in autism and mercury
literatures are paralleled in fragile X syndrome, a genetic disorder
wherein many affected individuals have traits worthy of an autism
diagnosis. These traits
include sensory alterations, emotional lability, appetite dysregulation,
social deficits, and eye-contact aversion (Hagerman).
Not only are fraX-related proteins (FRM1, FMR2) implicated in
amygdaloid function (Binstock, 1995; Yamagata, 1999), but neurons
involved in gaze- and eye-contact-aversion havebeen identified within
the primate temporal lobe and amygdaloid subareas (Rolls 1992, reviewed
in Binstock 1995). These
various findings in ASD, mercury poisoning, and fragile X suggest that
amygdaloid mercury is a mechanism for inducing traits central to or
associated with autism and the autism-spectrum of disorders.
Neuronal Organization & Head
Circumference: Several autism brain
studies have found evidence of increased neuronal cell replication, a
lowered ratio of glia to neurons, and an increased number of glial cells
(Bailey et al, 1996). Based
on these and other neuropathological findings, autism can be
characterized as “a disorder of neuronal organization, that is, the
development of the dendritic tree, synaptogenesis, and the development
of the complex connectivity within and between brain regions”
(Minshew, 1996).
Mercury
can interfere with neuronal migration and depress cell division in the
developing brain.
Post-mortem
brain tissue studies of exposed Japanese and Iraqi infants revealed
“abnormal neuronal cytoarchitecture characterized by ectopic cells and
disorganization of cellular layers” (EPA, 1997, p.3-86; Clarkson,
1997). Developmental neurtoxicity of Hg may also be due to binding of
mercury to sulfhydryl-rich tubulin, a component of microtubules
(Pendergrass et al, 1997). Intact
microtubules are necessary for proper cell migration and cell division
(EPA, review, 1997, p.32-88).
Rat pups dosed postnatally with methylmercury had significant reductions
in neuralcell adhesion molecules (NCAMs), which are critical during
neurodevelopment for proper synaptic structuring.
Sensitivity of NCAMs to methylmercury decreased as the
developmental age of the rats increased.
“Toxic perturbation of the developmentally-regulated expression
of NCAMs during brain formation may disturb the stereotypic formation of
neuronal contacts and could contribute to the behavioral and
morphological disturbances observed following methylmercury
poisoning" (Deyab et al, 1999).
Plioplys et al (1990) have found depressed expression of NCAM
serum fragments in autism.
Abnormalities
in neuronal growth during development are implicated in head size
differences found in both autism and mercury poisoning.
In autism, Fombonne and colleagues (1999) have found a subset of
subjects with macrocephaly and a subset with microcephaly.
The circumference abnormalities were progressive, so that, while
micro- and macrocephaly were present in 6% and 9% respectively of
children under 5 years, among those age10-16 years, the rates had
increased to 39% and 24% respectively.
Another study, by Stevenson et al (1997), had found just one
subject out of 18 with macrocephaly who had this abnormality present at
birth. The macrocephaly in
autism is generally believed to result from “increased neuronal growth
or decreased neuronal pruning.” The
cause of microcephaly has not been investigated.
The most
detailed study of head size in mercury poisoning, by Amin-Zaki et al
(1979), involved 32 Iraqi children exposed prenatally and followed up to
age 5 years. Eight (25%) had progressive microcephaly, i.e., the condition
was not present at birth. None
had developed macrocephaly, at least at the time of the study.
The microcephaly has been ascribed to neuronal death or apoptosis
from Hg intoxication.
vedi:
AUTISMO
+
Autism
REFERENCES
+
Autismo dai VACCINI
+
Autismo - La prova dei
Danni dei Vaccini
+
Bibliografia su Autismo dai vaccini +
Bibliografia
Danni dei vaccini +
Bibliografia danni
2 + Amish
senza autismo perche' NON vaccinano +
1.000 studi sui Danni dei Vaccini
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