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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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