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The following, in reverse date
order, is all significant new research, news reports, new books, and new
resources concerning
Parkinson's Disease and those medical disorders that often coincide with Parkinson's
Disease : Parkinsonism, Essential Tremor, Dystonia, Restless Legs Syndrome. It is compiled from an analysis of all newly published research,
news reports, new clinical trials, all newly published books, and
new resources. A summary and analysis of the new research are provided, as
well as links to the complete abstracts and news reports.

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18th August 2008 - News report
california
funds numerous stem cell projects
California's stem cell agency has awarded
$59 million to support the budgets of 23 researchers to carry out new stem cell
research projects. Human stem cells, particularly those found in embryos, are
primitive cell types that can be made to differentiate into virtually all the
specialized cells and tissues of the body. The California Institute for
Regenerative Medicine was created with a $3 billion bond issue in 2004, which
had been approved by voters. The Institute has so far awarded more than $614
million. They are consequently the world's biggest funders of stem cell
research.
It is claimed that stem cell research may be
invaluable for various medical disorders including Parkinson's Disease.
For more
information go to the
Complete article.
Although Parkinson's Disease is often claimed to be one of the major
concerns of stem cell
research, virtually none of the projects actually deal specifically with
Parkinson's Disease, as can be seen by the list of
proposed
projects. Most of the projects are far removed from the biochemistry
of Parkinson's Disease. Stem cell therapy is claimed to be of potential use in
Parkinson's Disease because stem cells could replace the massive cell loss that
is supposed to cause Parkinson's Disease. However, not a single study in the
entire medical literature has ever shown that there actually is massive cell
loss in Parkinson's Disease, or that massive cell loss causes Parkinson's
Disease.
17th August 2008 - New research
yeast
reduces cell damage in parkinson's disease
Journal of Clinical Investigation [2008] Aug 14. [Epub ahead of print] (Christophe
Lo Bianco, James Shorter, Etienne Régulier,
Hilal Lashuel, Takeshi Iwatsubo, Susan
Lindquist, Patrick Aebischer)
Complete study
Alpha-Synuclein can appear in the cells
involved in Parkinson's Disease (the dopaminergic neurons). For more
information, go to
Alpha-Synuclein. It has been debated as to whether this is to protect the
cells from damage, or
causes
cell damage. Researchers used Hsp104, which is found in yeast, to reduce the
formation of alpha-synuclein, and to prevent cell damage caused by
alpha-synuclein. Hsp140 works with Hsp70 and Hsp40, which are also found in
yeast. It is claimed that Hsp140 protects the cells against the effects of
alpha-synuclein by preventing the accumulation of alpha-synuclein. Researchers
consequently claim that Hsp140 could be used therapeutically in Parkinson's
Disease to prevent the cell damage that often accompanies Parkinson's Disease.
Hsp140, even in theory, does nothing to
directly increase dopamine formation, whose deficiency is the primary fault in
Parkinson's Disease. Hsp140 is a protein (which is a long chain of amino acids).
Consequently it could not be used in Parkinson's Disease anyway, because
proteins are too big to pass the blood brain barrier (the barrier between the
brain and the blood that prevents large or toxic substances from entering).
15th August 2008 - New book
TAKE ME HOME : PARKINSON'S, MY FATHER, MYSELF
Jonathan Taylor
When
Jonathan Taylor was eight, he began to find his father puzzling. The first
thing that happened was that his father couldn't remember Jonathan's
sister's name. Then he began to shake, to drive badly, to forget who or
where he was, and to mistake his son for someone else entirely. "Help help
help," his father would say, on and on, but there seemed to be no helping
him. Doctors diagnosed Parkinson's disease and an associated form of
dementia, and Jonathan gradually became one of his father's carers, taking
it in turn with his family to look after him for the next thirteen years.
Take Me Home is the story of a son's struggle for recognition from a
father who is being transformed mentally and physically by a ruinous
disease, and a writer's struggle to discover a father's strange and
largely secret past - who he was before he became a disappointed
headmaster in Stoke-on-Trent and, at the last, a trembling Parkinsonian
who sometimes mistook his son for Humphrey Bogart or a giraffe.
Click here for more details.
13th August 2008 - New research
NSAIDS
increase parkinson's disease
Current Drug Safety [2006] 1 (3) : 223-225 (Etminan M, Suissa S.)
Complete abstract
NSAIDs (Non-steroidal anti-inflammatory drugs) are drugs with analgesic,
antipyretic and, in higher doses, anti-inflammatory effects. They can reduce
pain, fever and inflammation.
For more information and a list of NSAIDs go
to
NSAID.
Recent studies have found NSAIDs to be protective against the development of
Parkinson's Disease. However, researchers decided to test this hypothesis using
the Saskatchewan drug plan database. Cases were defined as those having received
three prescriptions for a dopamine agonist within a year. Controls were matched
for age, calendar time and index date. Past users of NSAIDs had a slightly
higher risk of developing Parkinson's Disease, increasing their chances by up to
20%. However, the occurrence of Parkinson's Disease was up to 50% higher amongst
those people that were currently using NSAIDs. The researchers have given no
biochemical explanation as to why this might occur.
10th August 2008 - New review
carbon
disulfide as a cause of parkinson's disease
Carbon disulfide, usually in solvents or pesticides, can cause Parkinson's
Disease that is associated with other neurological symptoms. The effects can
persist for years after exposure to the carbon disulfide has ceased.
Potential sources : pesticides used as fumigants
[1], disulfiram (a drug
used in the treatment of chronic alcoholism)
[2], industrial solvents
[4], solvents used in the
production of viscose rayon and cellophane film [8] [9].
Means of toxicity : This is not established. However, carbon disulphide
interferes with pyridoxal 5-phosphate. Pyridoxal 5-phosphate is essential for
the formation of dopamine from L-dopa. So carbon disulphide may cause
Parkinson's Disease symptoms by reducing the formation of L-dopa.
Symptoms : atypical Parkinsonism (cerebellar signs, hearing loss, sensory
changes, cogwheel rigidity, decreased associated movements, distal sensory
shading, intention tremulousness, resting tremulousness, and nerve conduction
abnormalities)
[1]; Parkinsonism and
frontal lobe-like syndrome associated with
bilateral lesions of the lentiform
nuclei
[2]; balance problems,
impotence, and irritability, without tremor, cogwheel rigidity,
bradykinesia, or changes in facial
expression
[3]; Parkinsonism,
pyramidal signs, mild cognitive decline, and unresponsiveness to levodopa.
Two patients had a predominantly axonal and sensory polyneuropathy of the lower
legs with fasciculations in one of them. Parkinsonian features were progressive,
even after the patients had stopped work
[4]; encephalopathy with
Parkinsonism, pyramidal signs, cerebellar ataxia, and cognitive impairments, as
well as axonal polyneuropathy
[5]; polyneuropathy,
encephalopathy, tremor; Parkinsonian features, Parkinsonian features without
polyneuropathy or cerebellar signs
[6]; Carbon disulfide
toxicity may persist for several years after exposure to carbon disulfide has
ceased
[7].
Further references : [8] Journal of neuropathology
and experimental neurology [1945] 4 : 324 (R.Richter), [9] British journal of
industrial medicine [1954] 11 : 235 (E.C.Vigliani).
8th August 2008 - News research
parkinson's disease
stem cell line created
Cell [2008] (In-Hyun Park, Natasha Arora, Hongguang
Huo, Nimet Maherali, Tim Ahfeldt, Akiko Shimamura, M.William Lensch, Chad Cowan,
Konrad Hochedlinger, George Q.Daley)
Complete study
A new collection of
disease-specific stem cell lines have been produced, all of which were developed
using the new induced pluripotent stem cell (iPS) technique. The new cell lines
were developed from the cells of patients suffering from a range of conditions
from Down Syndrome to Parkinson's disease. The cell lines the researchers
produced carry
the
genes or genetic components for 10 different diseases, including Parkinson's
Disease. They wanted to
produce
a large number of disease models for stem cell research community to accelerate
research. They believe that these cells are invaluable tools that will allow
researchers to watch the development diseases outside of the patients, and that
this will make it possible to find new treatments, and eventually drugs, to slow
or even stop the course of a number of diseases, including Parkinson's Disease.
"The cell lines available from the iPS Core will allow stem cell researchers
around the world to explore possible gene therapies for some conditions, and
will aid in the development of drugs for others," Daley said.
The biochemistry of the dopaminergic neurons (the cells involved in Parkinson's
Disease) is already well known. Therefore, there is limited potential benefit
from further examination of these cells. Most medical researchers are not aware
of what is already known of the biochemistry of Parkinson's Disease.
Consequently, the vast majority of research being carried out in Parkinson's
Disease is fundamentally
flawed because of false assumptions concerning even the basic biochemistry.
4th August 2008 - News report
a ten year old
with parkinson's disease
At the age of ten, Andrew
Carnegie who is now 12 years old, started developing Parkinson's Disease
symptoms. He suffered from stiffness and cramps in the muscles. He lost his
balance easily, and fell frequently. Numerous attempts at obtaining a diagnosis
failed. He was not readily diagnosed with Parkinson's Disease because he was so
much younger than the false and stereotypical view of Parkinson's Disease only
occurring in old people. After he was eventually diagnosed, regular Sinemet
readily rid his symptoms.
For more information go to the
Complete article.
There
have previously
been children even younger than 10 years old who have had Parkinson's
Disease. The youngest known case of Parkinson's Disease was described in 1875 by
Henri Huchard who had a patient that had all of the symptoms of
Parkinson's Disease who was only three years old. A ten year old American girl
experienced her first symptom at only two
years old. It is uncommon for people under the age of thirty to develop
Parkinson's Disease, which usually occurs when people are significantly older.
However, Parkinson's Disease does not become progressively more likely with age,
because amongst the very oldest of people (those between 110 and 119 years old)
Parkinson's Disease is hardly known.
3rd August 2008 - New forum
the irish parkinson's disease
forum
The
Irish Parkinson's Disease Forum has been set up for Irish people with an
interest in Parkinson's Disease to
discuss Parkinson's Disease, and the issues and events in Ireland concerning it.
This includes the work and activities of the two Irish Parkinson's Disease
organisations : The Parkinson's Association of Ireland, and PALS support group,
which is primarily for younger people. The Irish Parkinson's Disease Forum is at
present the only Parkinson's Disease Forum for Irish people. The forum is new,
independent and open to anyone to become a member. For their web site,
double click on
The Irish Parkinson's Disease Forum
2nd August 2008 - New research
an
autoimmune hypothesis of parkinson's disease
Cell Transplantation [2008] 17
(4) : 363-372 (Monahan AJ, Warren M, Carvey PM.)
Complete abstract
Studies have
demonstrated that a number of substances readily cause toxic damage to the cells
that produce dopamine. However, neuroprotective strategies aimed at dealing with
this toxicity have been largely ineffective in treating Parkinson's Disease. The
researchers suggest that this may be because the progression of Parkinson's
Disease is a consequence of an additional mechanism. Whilst they considered
this, they discovered that animals whose dopamine producing cells were
exposed to the neurotoxins exhibited blood-brain barrier (BBB)
dysfunction.
The
blood brain barrier is what usually protects the brain from a number of
damaging substances. If the blood-brain barrier (BBB) in people with Parkinson's
Disease is disrupted, immune cells could enter brain and produce a
self-perpetuating (progressive) degenerative process. In this review, the
authors propose that peripheral immunity contributes to the degenerative process
of Parkinson's Disease and may be responsible for the progressive nature of the
disease. In order to understand this hypothesis, the authors claim that the
reader must question the conventional wisdom that the blood-brain barrier
is intact in Parkinson's Disease.
In support of their
theory, the leading researcher concerning the blood brain barrier in Parkinson's
Disease claimed several years ago that the blood brain barrier was dysfunctional
in Parkinson's Disease
[1]
[2]. However, these
studies were not age controlled, which is a considerable failing, because people
with Parkinson's Disease tend to be older. His subsequent studies effectively
nullified the basis for the blood brain barrier theory being dysfunctional in
Parkinson's Disease. He first found that the blood brain barrier tended towards
being dysfunctional in older people anyway, regardless of whether or not they
had Parkinson's Disease
[3]. He also found that
when people developed Parkinson's Disease they did not have a dysfunctional
blood brain barrier
[4]. The blood brain
barrier being no more dysfunctional in Parkinson's Disease than in anyone else
of a similar age leaves the autoimmune theory of Parkinson's Disease without the
basis it requires.
31st July 2008 - News release
michael j.fox foundation funds "RAPID
RESPONSE AWARDS"
The
Michael J. Fox Foundation is funding what they describe as "Cutting-edge
Approaches to Parkinson's Disease" under Rapid Response Innovation Awards 2008.
Among the projects funded are : (1) To determine whether a gene
silencing technique can be effective in reducing alpha-synuclein, a protein
whose aggregation, or clumping, in the
brain
is sometimes found in Parkinson’s
Disease. (2) Using newly induced pluripotent stem cell technology to shed
greater light on the Parkinson’s-implicated genes parkin and LRRK2. (3) To
better understand epidemiological findings that have consistently shown smoking
may protect against Parkinson's Disease. Researchers hope to elucidate the
mechanisms by which nicotine may protect dopamine neurons through development of
a screening test for small molecules that could increase nicotine receptor
expression in the brain. (4) To find better treatments for the digestive
problems that affect Parkinson’s patients’ quality of life, as well as test the
Braak hypothesis, which claims that Parkinson’s disease progresses through the
body to the brain in a series of stages starting in the gastrointestinal system.
For more information go to
The Michael J.Fox Foundation.
These latest projects,
are lacking in a sound scientific rationale : (1) Alpha synuclein cannot
logically be claimed to cause Parkinson's Disease because alpha synuclein occurs
in people without any trace of Parkinson's Disease. (2) The Parkin and LRRK2
genes have merely inclined a small proportion of people towards Parkinson's
Disease. They certainly aren't inevitable causes of Parkinson's Disease, even in
the small proportion of people that are affected by them. (3) Nicotine receptors
have never been shown to be responsible for Parkinson's Disease. Drugs already
known to affect the nicotine receptors have never rid anyone of Parkinson's
Disease. (4) The Braak hypothesis that Parkinson's Disease is caused by the
gastrointestinal system is equally unsound. L-dopa rids Parkinson's symptoms
despite not having any beneficial effect on the gastro-intestinal system. There
are dozens of cell types in the brain that would be affected by Braak's theory.
Yet Parkinson's Disease can occur without somebody simultaneously suffering from
every other neurological disorder.
28th July 2008 - New
review
parkinson's disease SYMPTOM QUESTIONNAIRES
Despite the increasing use of scanning methods to diagnose Parkinson's Disease,
symptom questionnaires remain the most common method of assessing symptoms.
The most commonly used symptom questionnaire is the
Unified Parkinson Disease Rating Scale (UPDRS).
The UPDRS was developed to address
the need for a comprehensive Parkinson's Disease measurement tool.
It encompasses earlier rating scales : Hoehn and Yahr staging scale, and the
modified Schwab and England activities of daily living scale. In monotherapy, a “Total UPDRS”
score is the combined sum of parts I, II, and III: 0 (not affected) to 176 (most
severely affected). In adjunct therapy, part IV is included. Part IV contains 11
questions and the scale can range from 0 to 23. For an understanding of the
UPDRS go to
UPDRS.
The Hoen and Yahr
characterises patients according to a scale of five stages of severity, from
Stage 1, which is mild, to Stage 5, which is incapacitated. For the
questionnaire go to the
Hoehn and Yahr scale.
The Schwab and England Activities of Daily Living assesses
patients in terms of their degree of independence concerning their functions -
with a range a percentages from 100% to 0%.
Rating can be assigned by the rater or the patient.
For the questionnaire go
to the
Schwab and England.
The PDQ39 assesses
the quality of life.
The PDQ-39 is the most widely used Parkinson's
Disease specific measure of health status. It contains thirty nine questions,
covering eight aspects of quality of life. Scores on the PDQ range from 0 to
100, with higher scores reflecting greater problems. For the questionnaire go to
PDQ 39. The PDQL is a self
administered measure that contains 37 items contained in four sub-scales :
parkinsonian symptoms, systemic symptoms, social functioning. An overall scale
can be derived, with a higher score indicating better perceived quality of life. For
the questionnaire go to the
PDQL.
For more information on the diagnosis of Parkinson's Disease, go to
Diagnosis of Parkinson's Disease.
26th July 2008 - New
research
HALLUCINATIONS IN parkinson's disease
Practical Neurology
[2008] 8 (4) : 238-241 (Poewe W.)
Complete abstract
Visual hallucinations occur in up to 40% of people with Parkinson's disease.
However, hallucinations are not actually due to Parkinson's Disease. Age and
cognitive decline are the most important intrinsic risk factors, but
hallucinations are often triggered by conditions such as infection and
dehydration.
The single most important trigger, however, is the use of CNS drugs,
especially drugs for Parkinson's Disease.
While hallucinations and psychosis can be triggered by amantadine and
anticholinergics, they are more commonly
experienced after changes in dopaminergic drugs. Dopamine agonists have the
greater potential to induce hallucinations compared with L-dopa. Attempting to
reduce Parkinson's Disease drugs is an important part in the management of these
symptoms, but atypical neuroleptics like clozapine or quetiapine are often also
used. Visual hallucinations in Parkinson's disease patients with dementia can
also be improved by treatment with the cholinesterase inhibitor rivastigmine.
22nd July 2008 - New
research
blood mechanisms claimed to cause
parkinson's disease
Many people with Parkinson's
Disease have elevated levels of a protein
called alpha-synuclein in their brains. As alpha-synuclein accumulates,
the resulting toxicity is claimed to cause damage to the cells that produce
dopamine. Researchers were surprised to notice that there were also large
amounts of alpha-synuclein in the blood. The
researchers
discovered that the activity of genes that control the formation of hemoglobin,
which is what enables blood to carry oxygen, precisely matched the activity of
the alpha-synuclein gene, suggesting a common switch controlling both the
formation of blood, and the damage that occurs in Parkinson's Disease. The protein called GATA-1, which turns on the
genes in the blood, was also a major switch for producing alpha-synuclein. They
also demonstrated that a related protein, GATA-2, was produced in brain cells
that were vulnerable to Parkinson's Disease. The researchers claim that being
able to reduce the formation of alpha-synuclein by 40% may be enough to
treat some forms of Parkinson's disease.
For more information go to the
Complete article.
The main weakness in the
claim that alpha-synuclein causes Parkinson's Disease and that its reduction
will rid it, is that a lot of people with Parkinson's Disease do not have large
amounts of alpha-synuclein. There is no evidence that alpha-synuclein actually
causes Parkinson's Disease, only that it can be associated with it.
Alpha-synuclein is associated with a variety of medical disorders that are not
Parkinson's Disease. Parkinson's Disease does not usually coincide with these
medical disorders as it would if alpha-synuclein was the cause of Parkinson's
Disease. Alpha-synuclein produced in the blood is unable to pass in to the brain
in order to cause Parkinson's Disease anyway.
19th July 2008 - News
release
michael j.fox foundation funds nine new
approaches
The Michael J. Fox Foundation
for Parkinson’s Research has announced approximately $2.4 million funding for
nine research projects. This annual program provides resources to help push
potential Parkinson's Disease drug targets toward clinical trials. Target
validation is a phase of drug development in which researchers work to determine
whether a molecule or mechanism of interest is a true drug target.
The
nine projects are (1) CaMKII as a Therapeutic Target in Parkinson's Disease, (2)
Evaluation of the Striatum-enriched Genes CalDAG-GEF1 and CalDAG-GEF2 as Targets
for the Treatment and Prevention of L-DOPA Induced Dyskinesia, (3) Hsp90 as a
Target for Neuroprotective Agents in Parkinson's Disease, (4) NBD Peptides in a
Non-Human Primate Model of Parkinson's Disease, (5) Mu Opioid Receptors as a
Drug Target for Treating Motor Fluctuations in PD, (6) Dopaminergic
Neuroprotection by Regulator of G-protein Signaling 10 (RGS10), (7) Validation
of the NR2D Subunit of the NMDA Receptor as a Therapeutic Target for Parkinson's
Disease, (8) NR2B as a Therapeutic Target in Parkinson's Disease, (9) SIRT1
Activators as Therapy for Parkinson's Disease.
For more information go to
The Michael J.Fox Foundation.
These projects all aim at
finding targets for new drugs. However, none of them, even in theory, address
the known biochemical fault in Parkinson's Disease, which is insufficient
formation of dopamine. All of the projects are biochemically far removed from
the possibility of increasing dopamine formation, and are consequently without
any scientific rationale that would justify their use. The Michael J.Fox
Foundation web site claims "We don't just fund research. We fund results."
However, despite their good intentions, none of the projects ever funded by the Foundation have resulted in anyone being rid of Parkinson's Disease.
16th July 2008 - New
research
suicide in parkinson's disease
Movement Disorders [2008] Jul
10; [Epub ahead of print] (Nazem S, Siderowf AD, Duda JE, Brown GK, Ten Have T,
Stern MB, Weintraub D.)
Complete abstract
In
Parkinson's disease, there is a high prevalence of depression. This is because
dopamine, whose deficiency normally causes the muscular symptoms of Parkinson's
Disease, also affects the emotions. Many people with Parkinson's Disease
consequently effectively become biochemically depressed. Depression increases
the likelihood of suicide and thoughts of death. However, little was known of
their prevalence in Parkinson's Disease. People with Parkinson's Disease were
assessed using the Paykel scale. Respondents answer each item either "yes"
or "no" to the following questions. The items can assess suicidality during the
past week, month, year or lifetime. More relevant to somebody with Parkinson's
Disease is for the answers to concern recent months :
1. Have you ever felt that life
was not worth living ?
2. Have you ever wished you were dead? for instance, that you could go to sleep
and not wake up ?
3. Have you ever thought of taking your life, even if you would not really do it
?
4. Have you ever reached the point where you seriously considered taking your
life or perhaps made plans how you would go about doing it?
5. Have you ever made an attempt to take your life ?
Extensive psychiatric,
neuropsychological, and neurological assessments were also carried out. Thoughts
of death occurred in 28% of patients. Thoughts of suicide occurred in 11% of
patients. Thoughts of either had occurred in 30% of patients. Of all those
assessed, 4% had attempted suicide during their lifetime. Depression was far
more common than normal. Even more common was impulse control disorder, but this
was probably due to Parkinson's Disease drugs, especially dopamine agonists.
Psychosis was also far more common in Parkinson's Disease, but this was also
probably due to Parkinson's Disease drugs, especially L-dopa.
13th July 2008 - New
research
essential tremor developing in to
parkinson's disease
Movement Disorders [2008] Jul
10; [Epub ahead of print] (Minen MT, Louis ED.)
Complete abstract
There is a blurred distinction between Essential Tremor and Parkinson's Disease.
There are people with Essential Tremor who have a degree of muscle rigidity,
which is more characteristic of Parkinson's Disease. Most people with
Parkinson's Disease have tremor, but around 30% don't have tremor at all.
Patients with essential tremor can develop Parkinson's Disease. However, few
studies have examined the clinical features of this combination syndrome.
Patients with ET-PD were compared to those with Parkinson's Disease and others
with only Essential Tremor. the time it took to go from the onset of Essential
Tremor to Parkinson's Disease was brief - less than five
years in nearly 40% of people, but in around 30% of people, Essential Tremor
took over 20 years before developing
in
to Parkinson's Disease. The gender
distribution of ET-PD was identical to the male dominance seen in Parkinson's
Disease (67.9% male), making it appear to be the same illness. This differed
from the gender distribution in Essential Tremor, in which there are roughly
equal numbers of men and women. The initial cardinal symptom of people who went
from Essential Tremor to Parkinson's Disease was rest tremor in 100% of
patients. In ET-PD, the side of greatest initial Essential Tremor severity
usually matched that of the greatest Parkinson's Disease severity. So the
co-occurrence of the two diagnoses in the same patient may be mechanistically
related.
10th July 2008 - New
review
dopamine receptors and dopamine agonists
It is widely claimed that
Parkinson's Disease is primarily due to a lack of dopamine, and L-dopa, which
forms it. However, dopamine on its own does nothing at all. Dopamine has to
stimulate the dopamine receptors before it has any effect. Dopamine receptors
are proteins, which means that they are a long chain of amino acids - just like
a pearl necklace is a long chain of pearls. There are five types of dopamine
receptor : D1, D2, D3, D4, D5. Each of them are different sizes, as they have a
different number of amino acids. D1 has 446. D2 has short and long versions,
with the short version being 414 long, and the long version being 443 long. D3
is 400 amino acids long. D4 is usually 387 amino acids long. However, there are
a large number of genetic variants of D4, especially amongst Americans.
Each
of these variants is less functional than the main form of D4, and so may
constitute one of the causes of Parkinson's Disease. D5 is 477 amino acids long.
The dopamine receptors do not all function in the same way either. The receptors
D2, D3 and D4 inhibit the excessive muscle contraction seen in Parkinson's
Disease. However, the receptors D1 and D5 are stimulatory, and so increase
muscle contraction. Dopamine (and L-dopa, which makes it) reduce the primary
symptoms of Parkinson's Disease, which is excessive muscle contraction because
the combined effect of D2, D3 and D4 is more powerful than the combined
stimulatory effect of D1 and D5.
Dopamine agonists make use of
the different functions of the dopamine receptors by primarily stimulating those
dopamine receptors that reduce excessive muscle contraction - usually D2 or D3.
For example, Mirapex primarily stimulates D3. Parlodel primarily stimulates D2.
Whilst Neupro stimulates three dopamine receptors D1, D2, D3. The problem with
taking dopamine agonists is that this can disproportionately stimulate certain
dopamine receptors rather than others - often giving rise to compulsive
behaviours, especially with those that stimulate D3. Continuous use of dopamine
agonists also makes the dopamine receptors progressively less sensitive.
Dopamine agonists consequently have progressively less effect, and can also
cause naturally produced dopamine to be less effective. In the long term this
can make Parkinson's Disease progressively worse.
5th July 2008 - New research
CALCIUM channel BLOCKERS - A CAUSE OF
PARKINSON'S DISEASE
Parkinsonism Related
Disorders [1998] 4 (4) : 211-214 (Garcia-Ruiz PJ, Javier Jimenez-Jimenez F,
Garcia de Yebenes J.)
Complete abstract
Calcium channel blockers are
drugs that are widely used to reduce high blood pressure. For more information
go to
Calcium channel blockers. The symptoms of Parkinson's Disease are a frequent
side effect of some calcium channel blockers (CCB). CCB-induced Parkinsonism
usually improves spontaneously after discontinuation of the offending
drug, but many
patients still exhibit persistent symptoms after their withdrawal. It is not
known whether
Parkinsonism
caused by Calcium channel blockers
represents sub-clinical Parkinson's disease unmasked by drugs. Researchers
studied the development of patients with CCB-induced Parkinsonism, and compared
their clinical characteristics with those people with idiopathic Parkinson's
Disease. Most patients with CCB-induced Parkinsonism improved spontaneously. Two
years after Calcium channel blocker withdrawal, only 14% exhibited akinetic
rigid syndrome. However, 92% of them still had tremor. Those people whose
Parkinson's Disease symptoms were caused by Calcium channel blockers differed
from other people with Parkinson's Disease in : age at onset (averaging 70
years old rather than 59 years old), presenting symptom (tremor at first
evaluation being more common), and a far more common history of arterial
hypertension.
4th July 2008 - News release
spheramine (retinal cell therapy) fails
clinical trials
It had been claimed
that a cell therapy using retinal pigment epithelial (RPE) cells, called
Spheramine, could improve the symptoms of people with Parkinson’s disease.
Spheramine consists of retinal pigment epithelial (RPE) cells attached to tiny
gelatin bead microcarriers implanted in the brain. The microcarriers
are
necessary for the cells to
survive in the brain. However, the
manufacturers, Titan Pharmaceuticals, have announced that Spheramine did not
meet the Phase IIb clinical study’s primary or secondary endpoints. There was no
significant difference in effect detected between Spheramine and sham surgery.
The Phase IIb trial was designed to explore the safety, tolerability and
efficacy of Spheramine. For
the statement go to
Titan Pharmaceuticals.
It
was pointed out on the Viartis web site, over two months before the clinical
trial results were known, that Spheramine did not account for the insufficient
dopamine formation that is known to cause Parkinson's Disease.
3rd July 2008 - New research
THYROID FUNCTION IN PARKINSON'S
DISEASE
Parkinsonism Related Disorders
[1999] 5 (1-2) : 49-53 (Bonuccelli U, D'Avino C, Caraccio N, Del Guerra P,
Casolaro A, Pavese N, Del Dotto P, Monzani F.)
Complete abstract
Thyroid disease is the endocrine dysfunction most frequently reported in
association with idiopathic Parkinson's Disease. The aim of this study was to
assess thyroid function in Parkinson's Disease, and to verify the effect of long
term
L-dopa or dopaminergic therapy on thyroid function. Thyroid dysfunction was
observed in over than 10% of people with Parkinson's Disease. No significant
difference in the prevalence of thyroid autoimmunity and dysfunction was found
between people with Parkinson's Disease and those with other nerological
disorders. Treatment with L-dopa and other dopaminergic drugs did not affect
thyroid function. The severity of Parkinson's Disease did not affect thyroid
function either. L-dopa and the thyroid hormones are made from L-tyrosine - a
nutrient normally consumed in the diet. Therefore, somebody who has both
Parkinson's Disease and Hypothyroidism may be suffering, at least partially,
from L-tyrosine deficiency, a problem that can be readily resolved using an
L-tyrosine supplement.
1st July 2008 - New web site
Hacia
adelante
- SPANISH LANGUAGE WEB SITE FOR PARKINSON'S
DISEASE
Hacia
adelante is a new Spanish language web site for Parkinson's Disease.
For the web site
go to :
Hacia adelante. “Hacia adelante” provides useful information for patients
and caregivers from diagnosis through disease progression, including information
on
managing Parkinson's Disease, treatment options, medical worksheet templates,
and resource links. Teva created the Spanish-language resource guide as part of
its commitment to providing helpful resources for all people affected by
Parkinson's Disease. “Hacia adelante” is available to anyone through their
neurologist or by simply visiting
www.parkinsonshealth.com under the "Take
Control" section. The free resource is available for viewing or download in
both Spanish and English.
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