Depression is a complex of psychological and physical symptoms. Low mood level or sadness is often the most prominent symptom. The common property of these symptoms is a decreased activity level in parts of the brain.
THE SYMPTOMS OF DEPRESSION
Depression may give one or more of these symptoms:
-Low mood level or sadness.
-Lack of joy or interest in activities that were joyful before.
-Pessimism.
-Feel of guilt of something without any substantial reason to feel so.
-Inferiority thoughts.
-Irritability.
-Slowness in the thought process.
-Slowness in interpreting sensorial stimuli.
-Slowness of digestion or other internal physical processes, and symptoms caused by this slowness, for example inflated stomach, constipation or difficulties by urination.
-Slow physical reactions.
Depression can be a mild disease that only causes some annoyance in the daily life, but can also get very serious and make a person totally unable to work and unable to participate in social life. By depression of some severity, there is also a greater risk of suicide.
Depression can occur in all age classes. In teenagers lack of interest in school work, withdrawal from social life and difficult mood can be signs of depression.
THE PHYSIOLOGICAL CHANGES THAT PRODUCE THE SYMPTOMS
By depression there is a decreased amount of neurotransmitters in parts of the central nervous system, mainly deficiency of serotonin, but also to some extend of noradrenalin, acetylcholine, dopamine or gamma-amino-butyric acid (GABA), or the nerve cells do not react properly by stimulation from neurotransmitters. A neurotransmitter is a signal substance that transmits the nerve signal through the junctions between two nerve cells.
Serotonin and noradrenalin cause nerve cells to send impulses along to other nerve cells, and thus increase the activity in the brain. Deficiency of these substances causes slowness in parts of the brain, and that again causes the depressive symptoms.
The role of GABA is the opposite, namely to slow down some nerve impulses, mainly those causing anxiety and panic response. Lack of GABA causes higher anxiety and easier panic response. Yet, lack of this transmitter also seems to cause depressive symptoms. This is because a too high activity in some brain processes may slow down other processes.
There are many causes and subtypes of depression with different physiological mechanisms involved.
TYPES OF DEPRESSION
Depression is often divided into subtypes according to exhibited symptoms.
1. Mono-polar depression and dysthymic disorder
By mono-polar depression there are pure depressive symptoms. Mild cases of mono-polar disorder that do not affect a persons ability to work and to participate in social activities are often called dysthymic disorder.
2. Bipolar disorder (manic-depressive disease) and cyclothymic disorder
In this condition there are periods with symptoms of depression – the depressive phase, alternating with periods of elevated mood level with increased mental and physical activity – the manic phase. In the manic phase, the affected person also sleeps poorly and has concentration difficulties. A mild form of this disease is called cyclothymic disorder.
3. Manic disorder
This condition is characterized by abnormally elevated mood, by unrealistic optimism, by lack of sleep and by hyperactive behaviour. Many psychiatrists think that this disorder is simply the same disease as bipolar disorder where the depressive face has not yet occurred.
4. Depression with mainly physical symptoms
Sometimes the physical symptoms of depression are alone or dominant, as for example: Digestive problems, constipation, difficulties with urination, slow response to sensorial stimuli or slow physical reactions.
CAUSES OF DEPRESSION
Two or more factors can have an effect simultaneously to cause depression. Depression can be an independent disease, or a part of other disease. Depression is also divided into different subtypes according to cause.
1. Reactive depression
This disease is simply a result from psychological stress, physical struggle or mental straining without proper rest or sleep over a long time period. The straining will simply wear out the nervous system or deplete the organism from nutrient necessary for the nervous system to work properly.
2. Endogenous depression
When there has not been any period of stress, straining or lack of rest that can explain the condition, the condition is often called endogenous depression. Inheritance is thought to be a part of the cause.
3. Depression by physical disease
Depression or depressive symptoms may be a symptom of physical disease. This is perhaps the most common cause of depression. Generally there are three categories of diseases that give depression:
Diseases often associated with depression are: Heart disease, Parkinson’s disease, stroke, hypertension or Cushing’s syndrome.
Mononucleosis or flu may trigger depression that continues after the infection has gone.
By lack of thyroid hormones, hypothyroidism, the metabolism in the whole body is slowed down, including the production of neurotransmitters in the brain. Therefore depression is an important symptom of hypothyroidism.
4. Depressive symptoms as a consequence of unsound lifestyle
A general unsound lifestyle with too less exercise, too much of stimulants like alcohol, coffee or tea, too less of important nutrient and too much of sugar and fat may give depressive symptoms, as well as physical problems.
5. Postnatal depression
Women will often have a period of depression after pregnancy and berth of the baby Pregnancy and berth is physically and mentally exhausting, and may drain the body for nutrient. This in turn can cause depressive symptoms
.
6. Seasonal affective disorder
Depression can occur in cold and dark periods of the year and go away in warm and light periods. Light stimulates brain activity, and lack of light is a causative factor.
TREATMENT OF DEPRESSION
Serious or prolonged depression is often treated with anti-depressive medication. Medicines used against depression generally increase the level of neurotransmitters like serotonin in the central nervous system, or they mimic the neurotransmitters.
The medications mostly used today increase the serotonin concentration by decreasing the removal of serotonin from the space around nerve cells. Examples of this medication type are: Fluoxetine (Prozac), fluvoxamine (Luvox), paroxetine (Paxil), escitalopram (Lexapro, Celexa), sentraline (zoloft).
By bipolar disorder in the manic face, heavy tranquilizers (neuroleptica) are used to stop the manic symptoms. By bipolar disorder, lithium salts are sometimes used to stabilize the condition, and prevent new outbreak of depressive or manic faces.
Psychotherapy is sometimes used by depression, usually in combination with medication.
Sometimes serious depression is treated by applying electric shock through the head, electroconvulsive therapy. The shock induces epileptic eruption of nerve signals through the brain and this gives cramps throughout the body. The cramps are alleviated or stopped by applying anaesthesia before the electroshock. This form of treatment is controversial, since it can cause memory loss and is suspected of causing brain damage. The possibility of brain damage is however denied by most psychiatrists.
By seasonal depression, light therapy maybe useful.
Adjustment of lifestyle should always be considered by depression or depressive symptoms. Lifestyle measures can sometimes be enough to cure depressive symptoms before a serious depression develop. Lifestyle adjustments can be:
– To slow down a stressful life with too much work or activities.
– Enough rest and sleep.
– A good diet with enough of necessary nutrients.
– Some physical exercise.
– Meditation.
– Supplement of vitamins, minerals, antioxidants, lecithin, amino acids and essential fatty acids.
– Stimulants like coffee or tea may help against depressive feelings in moderate amount. However, if you are a heavy user of these stimulants, you should cut down on your consumption.
There exist nutritional products in the marked to help against depressive symptoms. These contain ingredients that the brain uses as building blocks for neurotransmitters, for example amino acids and lecithin. They also often contain vitamins and minerals that the brain uses as tools to produce neurotransmitters, especially vitamin B6.
Supplements may further contain herbal extracts that trigger higher brain activity much like anti-depressive medications, but may have fewer side effects.
By: Knut Holt
Showing posts with label research. Show all posts
Showing posts with label research. Show all posts
Sunday, October 10, 2010
Saturday, July 10, 2010
Top Ten Things to Know About Stem Cell Treatments
by Juan Munevar
There are different types of stem cells—each with their own purpose.
There are many different types of stem cells that come from different places in the body or are formed at different times in our lives. These include embryonic stem cells that exist only at the earliest stages of development and various types of ‘tissue-specific’ or ‘adult’ stem cells that appear during fetal development and remain in our bodies throughout life.
Our bodies use different types of tissue-specific stem cells to fit a particular purpose. Tissue-specific stem cells are limited in their potential and largely make the cell types found in the tissue from which they are derived. For example, the blood-forming stem cells (or hematopoietic stem cells) in the bone marrow regenerate the blood, while neural stem cells in the brain make brain cells. A neural stem cell won’t spontaneously make a blood cell and likewise a hematopoietic stem cell won’t spontaneously make a brain cell. Thus, it is unlikely that a single cell type could be used to treat a multitude of unrelated diseases that involve different tissues or organs. Be wary of clinics that offer treatments with stem cells that originate from a part of the body that is different from the part being treated.
2. A single stem cell treatment will not work on a multitude of unrelated diseases or conditions.
As described above, each type of stem cell fulfills a specific function in the body and cannot be expected to make cell types from other tissues. Thus, it is unlikely that a single type of stem cell treatment can treat multiple unrelated conditions, such as diabetes and Parkinson’s disease. The underlying causes are very different and different cell types would need to be replaced to treat each condition. It is critical that the cell type used as a treatment be appropriate to the specific disease or condition.
Embryonic stem cells may one day be used to generate treatments for a range of human diseases. However, embryonic stem cells themselves cannot directly be used for therapies as they would likely cause tumors and are unlikely to become the cells needed to regenerate a tissue on their own. They would first need to be coaxed to develop into specialized cell types before transplantation. A major warning sign that a clinic may not be credible is when treatments are offered for a wide variety of conditions but rely on a single cell type.
3. Currently, there are very few widely accepted stem cell therapies.
The range of diseases where stem cell treatments have been shown to be beneficial in responsibly conducted clinical trials is still extremely restricted. The best defined and most extensively used is blood stem cell transplantation to treat diseases and conditions of the blood and immune system, or to restore the blood system after treatments for specific cancers. Some bone, skin and corneal diseases or injuries can be treated with grafting of tissue that depends upon stem cells from these organs. These therapies are also generally accepted as safe and effective by the medical community.
4. Just because people say stem cells helped them doesn’t mean they did.
There are three main reasons why a person might feel better that are unrelated to the actual stem cell treatment: the ‘placebo effect’, accompanying treatments, and natural fluctuations of the disease or condition. The intense desire or belief that a treatment will work can cause a person to feel like it has and to even experience positive physical changes, such as improved movement or less pain. This phenomenon is called the placebo effect. Even having a positive conversation with a doctor can cause a person to feel improvement. Likewise, other techniques offered along with stem cell treatment—such as changes to diet, relaxation, physical therapy, medication, etc.—may make a person feel better in a way that is unrelated to the stem cells. Also, the severity of symptoms of many conditions can change over time, resulting in either temporary improvement or decline, which can complicate the interpretation of the effectiveness of treatments. These factors are so widespread that without testing in a controlled clinical study, where a group that receives a treatment is carefully compared against a group that does not receive this treatment, it is very difficult to determine the real effect of any therapy. Be wary of clinics that measure or advertise their results primarily through patient testimonials.
5. A large part of why it takes time to develop new therapies is that science itself is a long and difficult process.
Science, in general, is a long and involved process. Understanding what goes wrong in disease or injury and how to fix it takes time. New ideas have to be tested first in a research laboratory, and many times the new ideas don’t work. Even once the basic science has been established, translating it into an effective medical treatment is a long and difficult process. Something that looks promising in cultured cells may fail as a therapy in an animal model and something that works in an animal model may fail when it is tried on humans. Once therapies are tested in humans, ensuring patient safety becomes a critical issue and this means starting with very few people until the safety and side effects are better understood.
6. To be used in treatments, stem cells will have to be instructed to behave in specific ways.
Bone marrow transplantation is typically successful because we are asking the cells to do exactly what they were designed to do, make more blood. For other conditions, we may want the cells to behave in ways that are different from how they would ordinarily work in the body. One of the greatest barriers to the development of successful stem cell therapies is to get the cells to behave in the desired way. Also, once transplanted inside the body the cells need to integrate and function in concert with the body’s other cells. For example, to treat many neurological conditions the cells we implant will need to grow into specific types of neurons, and to work they will also have to know which other neurons to make connections with and how to make these connections. We are still learning about how to direct stem cells to become the right cell type, to grow only as much as we need them to, and the best ways to transplant them. Discovering how to do all this will take time. Be wary of claims that stem cells will somehow just know where to go and what to do to treat a specific condition.
7. Just because stem cells came from your body doesn’t mean they are safe.
Every medical procedure has risks. While you are unlikely to have an immune response to your own cells, the procedures used to acquire, grow and deliver them are potentially risky. As soon as the cells leave your body they may be subjected to a number of manipulations that could change the characteristics of the cells. If they are grown in culture (a process called expansion), the cells may lose the normal mechanisms that control growth or may lose the ability to specialize into the cell types you need. The cells may become contaminated with bacteria, viruses or other pathogens that could cause disease. The procedure to either remove or inject the cells also carries risk, from introducing an infection to damaging the tissue into which they are injected.
8. There is something to lose by trying an unproven treatment.
Some of the conditions that clinics claim are treatable with stem cells are considered incurable by other means. It is easy to understand why people might feel they have nothing to lose from trying something even if it is unproven. However, there are very real risks of developing complications, both immediate and long-term, while the chance of experiencing a benefit is likely very low. In one publicized case, a young boy developed brain tumors as a result of a stem cell treatment. Participating in an unproven treatment may make a person ineligible to participate in upcoming clinical trials (see also number 9). Where cost is high, there may be long-term financial implications for patients, their families and communities. If travel is involved there are additional considerations, not the least of which is being away from family and friends.
9. An experimental treatment offered for sale is not the same as a clinical trial.
The fact that a procedure is experimental does not automatically mean that it is part of a research study or clinical trial. A responsible clinical trial can be characterized by a number of key features. There is preclinical data supporting that the treatment being tested is likely to be safe and effective. Before starting, there is oversight by an independent group such as an Institutional Review Board or medical ethics committee that protect patients’ rights, and in many countries the trial is assessed and approved by a national regulatory agency, such as the European Medicines Agency (EMA) or the U.S. Food and Drug Administration (FDA). The study itself is designed to answer specific questions about a new treatment or a new way of using current treatments, often with a control group to which the group of people receiving the new treatment is compared. Typically, the cost of the new treatment and trial monitoring is defrayed by the company developing the treatment or by local or national government funding. Beware of expensive treatments that have not passed successfully through clinical trials.
Responsibly-conducted clinical trials are critical to the development of new treatments as they allow us to learn whether these treatments are safe and effective. The ISSCR supports participation in responsible clinical trials after careful consideration of the issues highlighted on this site and in discussion with a trusted physician.
10. Stem cell science is constantly moving forward.
Stem cell science is extraordinarily promising. There have been great advances in treating diseases and conditions of the blood system using blood-forming stem cells, and these show us just how powerful stem cell therapies can be. Scientists all over the world are researching ways to harness stem cells and use them to learn more about, to diagnose, and to treat various diseases and conditions. Every day scientists are working on new ways to shape and control different types of stem cells in ways that are bringing us closer to developing new treatments. Many potential treatments are currently being tested in animal models and some have already been brought to clinical trials. In February 2010 the British company ReNeuron announced it had been approved to conduct a Phase I clinical trial of a neural stem cell treatment for stroke. The first embryonic stem cell-based treatment for acute spinal cord injury is currently under review by the U.S. Food and Drug Administration (FDA) and will hopefully move into clinical trials soon. Although it is sometimes hard to see, stem cell science is moving forward. We are tremendously optimistic that stem cell therapies will someday be available to treat a wide range of human diseases and conditions.
There are different types of stem cells—each with their own purpose.
There are many different types of stem cells that come from different places in the body or are formed at different times in our lives. These include embryonic stem cells that exist only at the earliest stages of development and various types of ‘tissue-specific’ or ‘adult’ stem cells that appear during fetal development and remain in our bodies throughout life.
Our bodies use different types of tissue-specific stem cells to fit a particular purpose. Tissue-specific stem cells are limited in their potential and largely make the cell types found in the tissue from which they are derived. For example, the blood-forming stem cells (or hematopoietic stem cells) in the bone marrow regenerate the blood, while neural stem cells in the brain make brain cells. A neural stem cell won’t spontaneously make a blood cell and likewise a hematopoietic stem cell won’t spontaneously make a brain cell. Thus, it is unlikely that a single cell type could be used to treat a multitude of unrelated diseases that involve different tissues or organs. Be wary of clinics that offer treatments with stem cells that originate from a part of the body that is different from the part being treated.
2. A single stem cell treatment will not work on a multitude of unrelated diseases or conditions.
As described above, each type of stem cell fulfills a specific function in the body and cannot be expected to make cell types from other tissues. Thus, it is unlikely that a single type of stem cell treatment can treat multiple unrelated conditions, such as diabetes and Parkinson’s disease. The underlying causes are very different and different cell types would need to be replaced to treat each condition. It is critical that the cell type used as a treatment be appropriate to the specific disease or condition.
Embryonic stem cells may one day be used to generate treatments for a range of human diseases. However, embryonic stem cells themselves cannot directly be used for therapies as they would likely cause tumors and are unlikely to become the cells needed to regenerate a tissue on their own. They would first need to be coaxed to develop into specialized cell types before transplantation. A major warning sign that a clinic may not be credible is when treatments are offered for a wide variety of conditions but rely on a single cell type.
3. Currently, there are very few widely accepted stem cell therapies.
The range of diseases where stem cell treatments have been shown to be beneficial in responsibly conducted clinical trials is still extremely restricted. The best defined and most extensively used is blood stem cell transplantation to treat diseases and conditions of the blood and immune system, or to restore the blood system after treatments for specific cancers. Some bone, skin and corneal diseases or injuries can be treated with grafting of tissue that depends upon stem cells from these organs. These therapies are also generally accepted as safe and effective by the medical community.
4. Just because people say stem cells helped them doesn’t mean they did.
There are three main reasons why a person might feel better that are unrelated to the actual stem cell treatment: the ‘placebo effect’, accompanying treatments, and natural fluctuations of the disease or condition. The intense desire or belief that a treatment will work can cause a person to feel like it has and to even experience positive physical changes, such as improved movement or less pain. This phenomenon is called the placebo effect. Even having a positive conversation with a doctor can cause a person to feel improvement. Likewise, other techniques offered along with stem cell treatment—such as changes to diet, relaxation, physical therapy, medication, etc.—may make a person feel better in a way that is unrelated to the stem cells. Also, the severity of symptoms of many conditions can change over time, resulting in either temporary improvement or decline, which can complicate the interpretation of the effectiveness of treatments. These factors are so widespread that without testing in a controlled clinical study, where a group that receives a treatment is carefully compared against a group that does not receive this treatment, it is very difficult to determine the real effect of any therapy. Be wary of clinics that measure or advertise their results primarily through patient testimonials.
5. A large part of why it takes time to develop new therapies is that science itself is a long and difficult process.
Science, in general, is a long and involved process. Understanding what goes wrong in disease or injury and how to fix it takes time. New ideas have to be tested first in a research laboratory, and many times the new ideas don’t work. Even once the basic science has been established, translating it into an effective medical treatment is a long and difficult process. Something that looks promising in cultured cells may fail as a therapy in an animal model and something that works in an animal model may fail when it is tried on humans. Once therapies are tested in humans, ensuring patient safety becomes a critical issue and this means starting with very few people until the safety and side effects are better understood.
6. To be used in treatments, stem cells will have to be instructed to behave in specific ways.
Bone marrow transplantation is typically successful because we are asking the cells to do exactly what they were designed to do, make more blood. For other conditions, we may want the cells to behave in ways that are different from how they would ordinarily work in the body. One of the greatest barriers to the development of successful stem cell therapies is to get the cells to behave in the desired way. Also, once transplanted inside the body the cells need to integrate and function in concert with the body’s other cells. For example, to treat many neurological conditions the cells we implant will need to grow into specific types of neurons, and to work they will also have to know which other neurons to make connections with and how to make these connections. We are still learning about how to direct stem cells to become the right cell type, to grow only as much as we need them to, and the best ways to transplant them. Discovering how to do all this will take time. Be wary of claims that stem cells will somehow just know where to go and what to do to treat a specific condition.
7. Just because stem cells came from your body doesn’t mean they are safe.
Every medical procedure has risks. While you are unlikely to have an immune response to your own cells, the procedures used to acquire, grow and deliver them are potentially risky. As soon as the cells leave your body they may be subjected to a number of manipulations that could change the characteristics of the cells. If they are grown in culture (a process called expansion), the cells may lose the normal mechanisms that control growth or may lose the ability to specialize into the cell types you need. The cells may become contaminated with bacteria, viruses or other pathogens that could cause disease. The procedure to either remove or inject the cells also carries risk, from introducing an infection to damaging the tissue into which they are injected.
8. There is something to lose by trying an unproven treatment.
Some of the conditions that clinics claim are treatable with stem cells are considered incurable by other means. It is easy to understand why people might feel they have nothing to lose from trying something even if it is unproven. However, there are very real risks of developing complications, both immediate and long-term, while the chance of experiencing a benefit is likely very low. In one publicized case, a young boy developed brain tumors as a result of a stem cell treatment. Participating in an unproven treatment may make a person ineligible to participate in upcoming clinical trials (see also number 9). Where cost is high, there may be long-term financial implications for patients, their families and communities. If travel is involved there are additional considerations, not the least of which is being away from family and friends.
9. An experimental treatment offered for sale is not the same as a clinical trial.
The fact that a procedure is experimental does not automatically mean that it is part of a research study or clinical trial. A responsible clinical trial can be characterized by a number of key features. There is preclinical data supporting that the treatment being tested is likely to be safe and effective. Before starting, there is oversight by an independent group such as an Institutional Review Board or medical ethics committee that protect patients’ rights, and in many countries the trial is assessed and approved by a national regulatory agency, such as the European Medicines Agency (EMA) or the U.S. Food and Drug Administration (FDA). The study itself is designed to answer specific questions about a new treatment or a new way of using current treatments, often with a control group to which the group of people receiving the new treatment is compared. Typically, the cost of the new treatment and trial monitoring is defrayed by the company developing the treatment or by local or national government funding. Beware of expensive treatments that have not passed successfully through clinical trials.
Responsibly-conducted clinical trials are critical to the development of new treatments as they allow us to learn whether these treatments are safe and effective. The ISSCR supports participation in responsible clinical trials after careful consideration of the issues highlighted on this site and in discussion with a trusted physician.
10. Stem cell science is constantly moving forward.
Stem cell science is extraordinarily promising. There have been great advances in treating diseases and conditions of the blood system using blood-forming stem cells, and these show us just how powerful stem cell therapies can be. Scientists all over the world are researching ways to harness stem cells and use them to learn more about, to diagnose, and to treat various diseases and conditions. Every day scientists are working on new ways to shape and control different types of stem cells in ways that are bringing us closer to developing new treatments. Many potential treatments are currently being tested in animal models and some have already been brought to clinical trials. In February 2010 the British company ReNeuron announced it had been approved to conduct a Phase I clinical trial of a neural stem cell treatment for stroke. The first embryonic stem cell-based treatment for acute spinal cord injury is currently under review by the U.S. Food and Drug Administration (FDA) and will hopefully move into clinical trials soon. Although it is sometimes hard to see, stem cell science is moving forward. We are tremendously optimistic that stem cell therapies will someday be available to treat a wide range of human diseases and conditions.
Tuesday, June 22, 2010
Report: Spine Stimulation May Benefit Parkinson’s Disease Patients
By Steven Marsh
Patients who have been diagnosed with Parkinson’s disease (PD) may have relief from symptoms associated with the condition in the near future, according to a study presented at the 2010 American Society for Stereotactical and Functional Neurosurgery.
In an effort to find potential treatments for individuals with the nervous system disorder, a team of researchers at Rhode Island Hospital conducted a series of exercises that stimulated the spinal cord on an animal model, which showed signs of PD. Because the findings displayed better motor function in the animal, the investigators tested the treatment with spinal cord simulation on a male patient aged 82 years.
While the individual wasn’t receiving any form of medication as treatment for the disorder, researchers used different frequencies of stimulation to determine if a human would experience similar results compared to the animal model.
The researchers discovered that high stimulation frequencies made it easier for the patient to walk, while low frequencies worsened PD side effects.
While the results of the study did give investigators some insight as to how to treat PD patients, clinical trials with a larger group of patients would be more beneficial to developing treatment.
Finding therapies for this disorder is growing in interest throughout the medical world, as QR Pharma and Massachusetts General Hospital have launched research to determine a way to block a protein associated the development of PD.ADNFCR-1960-ID-19845071-ADNFCR
Patients who have been diagnosed with Parkinson’s disease (PD) may have relief from symptoms associated with the condition in the near future, according to a study presented at the 2010 American Society for Stereotactical and Functional Neurosurgery.
In an effort to find potential treatments for individuals with the nervous system disorder, a team of researchers at Rhode Island Hospital conducted a series of exercises that stimulated the spinal cord on an animal model, which showed signs of PD. Because the findings displayed better motor function in the animal, the investigators tested the treatment with spinal cord simulation on a male patient aged 82 years.
While the individual wasn’t receiving any form of medication as treatment for the disorder, researchers used different frequencies of stimulation to determine if a human would experience similar results compared to the animal model.
The researchers discovered that high stimulation frequencies made it easier for the patient to walk, while low frequencies worsened PD side effects.
While the results of the study did give investigators some insight as to how to treat PD patients, clinical trials with a larger group of patients would be more beneficial to developing treatment.
Finding therapies for this disorder is growing in interest throughout the medical world, as QR Pharma and Massachusetts General Hospital have launched research to determine a way to block a protein associated the development of PD.ADNFCR-1960-ID-19845071-ADNFCR
Sunday, May 10, 2009
Mayo Clinic Study Finds Anemia Might be Associated With Development of Parkinson's Disease
Mayo Clinic Study Finds Anemia Might be Associated With Development of Parkinson's Disease
ROCHESTER, Minn. — Results of a new Mayo Clinic study support an association between anemia experienced early in life and the development of Parkinson's disease many years later. The findings will be presented at the American Academy of Neurology Annual Meeting in Seattle on April 30, 2009.
"We were surprised to discover that chronic anemia or low levels of hemoglobin were linked to the risk of Parkinson's disease 20-30 years later," says Walter Rocca, M.D. an author of the study and a neurologist at Mayo Clinic.
Hemoglobin is the protein that transports oxygen in the blood, an essential element for life. "We looked at both anemia as diagnosed by a physician and low hemoglobin values," Dr. Rocca says. "Both were associated with an increased risk of Parkinson's disease. This might indicate that Parkinson's disease actually starts 20--30 years before we see any motor changes in the body."
The case-control study included 196 people who developed Parkinson's disease in Olmsted County, Minn., from 1976 through 1995. Each case was matched by age and sex to a general population control subject who was not affected by Parkinson's disease. The medical records of cases and controls were reviewed using the resources of the Rochester Epidemiology Project to determine if there was a link between anemia or low hemoglobin levels and the risk of developing Parkinson's disease many years later. Anemia was significantly more common in the history of cases than in the history of controls.
Dr. Rocca and his team hope to replicate these results in another population group. "We first need to confirm the study results. If the findings are replicated, we will try to understand what are the underlying mechanisms. Understanding the mechanisms may lead to new ways to prevent or treat Parkinson's disease," Dr. Rocca says.
Other members of the Mayo Clinic research team included Rodolfo Savica, M.D.; Justin Carlin; Brandon Grossardt; James Bower, M.D.; and Demetrius Maraganore, M.D.
ROCHESTER, Minn. — Results of a new Mayo Clinic study support an association between anemia experienced early in life and the development of Parkinson's disease many years later. The findings will be presented at the American Academy of Neurology Annual Meeting in Seattle on April 30, 2009.
"We were surprised to discover that chronic anemia or low levels of hemoglobin were linked to the risk of Parkinson's disease 20-30 years later," says Walter Rocca, M.D. an author of the study and a neurologist at Mayo Clinic.
Hemoglobin is the protein that transports oxygen in the blood, an essential element for life. "We looked at both anemia as diagnosed by a physician and low hemoglobin values," Dr. Rocca says. "Both were associated with an increased risk of Parkinson's disease. This might indicate that Parkinson's disease actually starts 20--30 years before we see any motor changes in the body."
The case-control study included 196 people who developed Parkinson's disease in Olmsted County, Minn., from 1976 through 1995. Each case was matched by age and sex to a general population control subject who was not affected by Parkinson's disease. The medical records of cases and controls were reviewed using the resources of the Rochester Epidemiology Project to determine if there was a link between anemia or low hemoglobin levels and the risk of developing Parkinson's disease many years later. Anemia was significantly more common in the history of cases than in the history of controls.
Dr. Rocca and his team hope to replicate these results in another population group. "We first need to confirm the study results. If the findings are replicated, we will try to understand what are the underlying mechanisms. Understanding the mechanisms may lead to new ways to prevent or treat Parkinson's disease," Dr. Rocca says.
Other members of the Mayo Clinic research team included Rodolfo Savica, M.D.; Justin Carlin; Brandon Grossardt; James Bower, M.D.; and Demetrius Maraganore, M.D.
Saturday, May 2, 2009
Parkinson's Disease: More Than Shaking Going On Researchers discovering non-motor symptoms may happen first
Parkinson's Disease: More Than Shaking Going On Researchers discovering non-motor symptoms may happen first
(live-PR.com) - TORONTO, ONTARIO -- (Marketwire) -- 04/21/09 -- Parkinson's is much more than a tremor. That's a message Parkinson Society Canada hopes to drive home this April during Parkinson's Awareness Month.
In Parkinson's, the most common symptoms are movement-related: tremor, slowness, muscle stiffness and balance problems. However, by the time Parkinson's is diagnosed, people have already lost 60 to 70 percent of the dopamine-producing cells. Now researchers are discovering that non-motor symptoms such as sleep problems, depression and smell loss may represent the earliest signs of Parkinson's, for some people, and may appear years before the diagnosis.
In research at Montreal's Sacre-Coeur Hospital, Dr. Ronald Postuma, assistant professor of neurology at McGill University found that people with a rare sleep disorder where they physically acted out their dreams had a 50% risk of developing Parkinson's disease or dementia within 12 years. The patients had REM-sleep behaviour disorder, which Postuma describes as "punching and yelling or kicking out while asleep. It mostly affects people in their 60s and 70s, almost always men." Not all will develop a neurodegenerative disease but Postuma says, "Patients with true REM-sleep behaviour disorder have a considerable risk of developing Parkinson's disease."
Depression and anxiety can surface early in Parkinson's. "Many people, as they're starting to lose their dopamine, may not yet have developed a tremor, slowness or trouble walking, but may feel anxious and depressed," says Dr. Susan Fox, assistant professor of neurology at University of Toronto. "Depression is also part of Parkinson's disease itself and not just a reaction to having a chronic neurological disorder." Fox notes untreated depression can reduce quality of life.
Smell loss is a common occurrence. "The general consensus is that the changes in olfaction (sense of smell) occur about five years before the Parkinson's diagnosis." says Dr. Harold Robertson, a professor in the Brain Repair Centre and Department of Pharmacology at Dalhousie University in Halifax. "That could give us enough lead time to try to stop the process."
Joyce Gordon, Parkinson Society Canada President and CEO says "The more dollars we can put towards Parkinson's research, the sooner we may be able to establish if there is a definite link to Parkinson's when a person has sleep problems, depression or loss of smell. This would lay the groundwork for developing treatments to delay or stop this debilitating disease in its tracks. The answers can't come soon enough for the 100,000 Canadians who have Parkinson's disease and those who are unknowingly at risk."
In the meantime, the first step for anyone experiencing difficulties with sleep or mood is to see a doctor for a proper diagnosis. REM sleep behaviour disorder and depression are treatable. Smell loss is not currently treatable but is worth mentioning to the doctor, during a routine visit, as it may be due to a variety of causes.
Parkinson's is a progressive neurological disease for which there is no known cause or cure. When cells in the brain that normally produce a chemical called "dopamine" die, symptoms of Parkinson's appear. The most common symptoms are: tremor (shaking), slowness in movements, muscle stiffness and problems with balance. Other symptoms that may also occur for some people include fatigue, difficulties with speech and writing, sleep disorders, depression and cognitive changes.
For over 40 years, Parkinson Society Canada (PSC) has been the national voice of people living with Parkinson's disease. PSC has over 230 chapters and support groups. PSC's mission is to fund research, support services, advocacy and education.
For more information on Parkinson's disease and Parkinson Society Canada, visit the PSC website at www.parkinson.ca : www.parkinson.ca or call 1-800-565-3000.
Contacts:
Parkinson Society Canada
John Provenzano
416-227-3399 or 1-800-565-3000 ext 3399
John.provenzano@parkinson.ca : John.provenzano@parkinson.ca
(live-PR.com) - TORONTO, ONTARIO -- (Marketwire) -- 04/21/09 -- Parkinson's is much more than a tremor. That's a message Parkinson Society Canada hopes to drive home this April during Parkinson's Awareness Month.
In Parkinson's, the most common symptoms are movement-related: tremor, slowness, muscle stiffness and balance problems. However, by the time Parkinson's is diagnosed, people have already lost 60 to 70 percent of the dopamine-producing cells. Now researchers are discovering that non-motor symptoms such as sleep problems, depression and smell loss may represent the earliest signs of Parkinson's, for some people, and may appear years before the diagnosis.
In research at Montreal's Sacre-Coeur Hospital, Dr. Ronald Postuma, assistant professor of neurology at McGill University found that people with a rare sleep disorder where they physically acted out their dreams had a 50% risk of developing Parkinson's disease or dementia within 12 years. The patients had REM-sleep behaviour disorder, which Postuma describes as "punching and yelling or kicking out while asleep. It mostly affects people in their 60s and 70s, almost always men." Not all will develop a neurodegenerative disease but Postuma says, "Patients with true REM-sleep behaviour disorder have a considerable risk of developing Parkinson's disease."
Depression and anxiety can surface early in Parkinson's. "Many people, as they're starting to lose their dopamine, may not yet have developed a tremor, slowness or trouble walking, but may feel anxious and depressed," says Dr. Susan Fox, assistant professor of neurology at University of Toronto. "Depression is also part of Parkinson's disease itself and not just a reaction to having a chronic neurological disorder." Fox notes untreated depression can reduce quality of life.
Smell loss is a common occurrence. "The general consensus is that the changes in olfaction (sense of smell) occur about five years before the Parkinson's diagnosis." says Dr. Harold Robertson, a professor in the Brain Repair Centre and Department of Pharmacology at Dalhousie University in Halifax. "That could give us enough lead time to try to stop the process."
Joyce Gordon, Parkinson Society Canada President and CEO says "The more dollars we can put towards Parkinson's research, the sooner we may be able to establish if there is a definite link to Parkinson's when a person has sleep problems, depression or loss of smell. This would lay the groundwork for developing treatments to delay or stop this debilitating disease in its tracks. The answers can't come soon enough for the 100,000 Canadians who have Parkinson's disease and those who are unknowingly at risk."
In the meantime, the first step for anyone experiencing difficulties with sleep or mood is to see a doctor for a proper diagnosis. REM sleep behaviour disorder and depression are treatable. Smell loss is not currently treatable but is worth mentioning to the doctor, during a routine visit, as it may be due to a variety of causes.
Parkinson's is a progressive neurological disease for which there is no known cause or cure. When cells in the brain that normally produce a chemical called "dopamine" die, symptoms of Parkinson's appear. The most common symptoms are: tremor (shaking), slowness in movements, muscle stiffness and problems with balance. Other symptoms that may also occur for some people include fatigue, difficulties with speech and writing, sleep disorders, depression and cognitive changes.
For over 40 years, Parkinson Society Canada (PSC) has been the national voice of people living with Parkinson's disease. PSC has over 230 chapters and support groups. PSC's mission is to fund research, support services, advocacy and education.
For more information on Parkinson's disease and Parkinson Society Canada, visit the PSC website at www.parkinson.ca : www.parkinson.ca or call 1-800-565-3000.
Contacts:
Parkinson Society Canada
John Provenzano
416-227-3399 or 1-800-565-3000 ext 3399
John.provenzano@parkinson.ca : John.provenzano@parkinson.ca
Sunday, April 19, 2009
Shedding some light on Parkinson's treatment
Shedding some light on Parkinson's treatment
EUREKALERT
Contact: Lisa Van Pay
lvanpay@nsf.gov
703-292-8796
National Science Foundation
Scientists use optical approach to study deep brain stimulation
A research team lead by Karl Deisseroth in the bioengineering department at Stanford University has developed a technique to systematically characterize disease circuits in the brain. By precisely controlling individual components of the circuit implicated in Parkinson's disease, the team has identified a specific group of cells as direct targets of deep brain stimulation (DBS), a Parkinson's treatment.
Termed optogenetics, the NSF-funded technology uses light-activated proteins, originally isolated from bacteria, in combination with genetic approaches to control specific parts of the brain. The technique is a vast improvement over previous methods because it allows researchers to precisely stimulate neurons and measure the effect of treatment simultaneously in animals with Parkinson's-like symptoms.
Published in the April 17 issue of Science, Deisseroth's team found they could reduce disease symptoms by preferentially activating neurons that link to the subthalamic nucleus region of the brain. First, these specific cells were treated in a way that made them sensitive to stimulation by blue light, then the team implanted an optical fiber in the brain.
When researchers rapidly flashed blue light inside the animals' brains the disease symptoms improved. In contrast, treating with slower flashes of light actually made the symptoms worse, and targeting other kinds of cells had no effect at all, indicating both proper cell type and stimulation frequency are crucial components of effective treatment. Flashing blue light on portions of the same neurons found closer to the outer surface of the brain had an effect similar to treatment deep within the brain, raising the possibility that researchers may be able to develop treatments that are less invasive than current options.
Approved as a medical treatment in 1997, DBS remains controversial because it doesn't work on all patients. Used to treat Parkinson's disease, depression and movement disorders, DBS involves surgical implantation of a brain pacemaker, which sends electrical impulses into the brain. In the past, researchers have been unable to understand the effective mechanism of DBS because the electrical signal emitted by DBS devices interferes with the ability to observe brain activity.
Explains Deisseroth, "The brain is an electrical device, but it is a very complicated device. Think of it as an orchestra without sections: all of the types of instruments, or cells, are mixed together. Treatments like DBS are unrefined, in that they stimulate all of the cells or instruments. The optogenetic approach allows us to control stimulation of specific cells in the brain on the appropriate timescale, much like a conductor directing specific sections of an orchestra at the appropriate time."
Production of new therapies is always a long-term goal, but for now Deisseroth and his group are focused on mapping disease circuits and understanding brain function. "We need to understand the players before we can develop effective treatment strategies," he stated.
EUREKALERT
Contact: Lisa Van Pay
lvanpay@nsf.gov
703-292-8796
National Science Foundation
Scientists use optical approach to study deep brain stimulation
A research team lead by Karl Deisseroth in the bioengineering department at Stanford University has developed a technique to systematically characterize disease circuits in the brain. By precisely controlling individual components of the circuit implicated in Parkinson's disease, the team has identified a specific group of cells as direct targets of deep brain stimulation (DBS), a Parkinson's treatment.
Termed optogenetics, the NSF-funded technology uses light-activated proteins, originally isolated from bacteria, in combination with genetic approaches to control specific parts of the brain. The technique is a vast improvement over previous methods because it allows researchers to precisely stimulate neurons and measure the effect of treatment simultaneously in animals with Parkinson's-like symptoms.
Published in the April 17 issue of Science, Deisseroth's team found they could reduce disease symptoms by preferentially activating neurons that link to the subthalamic nucleus region of the brain. First, these specific cells were treated in a way that made them sensitive to stimulation by blue light, then the team implanted an optical fiber in the brain.
When researchers rapidly flashed blue light inside the animals' brains the disease symptoms improved. In contrast, treating with slower flashes of light actually made the symptoms worse, and targeting other kinds of cells had no effect at all, indicating both proper cell type and stimulation frequency are crucial components of effective treatment. Flashing blue light on portions of the same neurons found closer to the outer surface of the brain had an effect similar to treatment deep within the brain, raising the possibility that researchers may be able to develop treatments that are less invasive than current options.
Approved as a medical treatment in 1997, DBS remains controversial because it doesn't work on all patients. Used to treat Parkinson's disease, depression and movement disorders, DBS involves surgical implantation of a brain pacemaker, which sends electrical impulses into the brain. In the past, researchers have been unable to understand the effective mechanism of DBS because the electrical signal emitted by DBS devices interferes with the ability to observe brain activity.
Explains Deisseroth, "The brain is an electrical device, but it is a very complicated device. Think of it as an orchestra without sections: all of the types of instruments, or cells, are mixed together. Treatments like DBS are unrefined, in that they stimulate all of the cells or instruments. The optogenetic approach allows us to control stimulation of specific cells in the brain on the appropriate timescale, much like a conductor directing specific sections of an orchestra at the appropriate time."
Production of new therapies is always a long-term goal, but for now Deisseroth and his group are focused on mapping disease circuits and understanding brain function. "We need to understand the players before we can develop effective treatment strategies," he stated.
Monday, March 30, 2009
23andMe already testing for rare Parkinson's mutations?
23andMe already testing for rare Parkinson's mutations?
Posted on: March 23, 2009 9:15 AM, by Daniel MacArthur
This casual aside on a recent post on personal genomics company 23andMe's corporate blog caught my eye:
Mutations in several other genes have also been associated with Parkinson's disease, but these are extremely rare. Many have been found only in one or two families. While these mutations are so rare that they are not covered by 23andMe (to date we have found no customers with any of them), studying them could help scientists better understand the mechanisms of Parkinson's generally... [my emphasis]
In other words, the company already has probes on its custom chip targeting these variants, but it isn't yet reporting results back to customers.
Why isn't it reporting back? If you'd asked me a couple of months ago, I'd say the motivation was probably to avoid the regulatory hassles associated with testing overtly clinical markers - but the company's willingness to provide results for large-effect variants associated with breast cancer pretty much rules that out.
Instead, the most likely reason to hold back on giving results back to consumers is (perfectly reasonable) caution about the reliability of the test. Screening for extremely rare variants is tricky for two reasons: firstly, since there are very few individuals around who carry the mutation, obtaining positive controls is difficult; and secondly, screening accuracy needs to be extremely high to keep down the rate of false positives.
To illustrate that last point, let's say there was a genetic variant with a population frequency of just 0.1% (1 in every 1000 people carry it)*. Now, let's say you have a test with false positive and false negative rates of just 1 in every 1000 tests, and you run that test on one million people. Of the 1000 carriers in the population, the test will only miss one; but it will also give a positive result for 999 people who are non-carriers. In other words, even for this extremely accurate hypothetical test, only 50% of the people who test positive are actually carriers.
This means that testing for rare variants requires exceptionally high standards of accuracy, probably higher than could reasonably be expected from chip-based assays. Given the risks of reporting potentially unreliable results back to customers for serious risk variants it makes good sense for 23andMe to hold off until it has developed extra assays for quality control; and it's unlikely to do this until it has seen at least a few customers who actually do test positive for the variant in question.
As for obtaining samples from real carriers to enable the development of validation assays: what better way to do that than to recruit 10,000 customers suffering from Parkinson's? Targeted recruitment of customers with other diseases will no doubt follow.
It is now abundantly clear that 23andMe is intent on moving into the overtly clinical domain; Navigenics' purchase of its Affymetrix testing lab and deCODE's move into disease-specific genetic tests are other signs that this is a shift that will involve the entire personal genomics industry.
Personal genomics is getting serious.
Posted on: March 23, 2009 9:15 AM, by Daniel MacArthur
This casual aside on a recent post on personal genomics company 23andMe's corporate blog caught my eye:
Mutations in several other genes have also been associated with Parkinson's disease, but these are extremely rare. Many have been found only in one or two families. While these mutations are so rare that they are not covered by 23andMe (to date we have found no customers with any of them), studying them could help scientists better understand the mechanisms of Parkinson's generally... [my emphasis]
In other words, the company already has probes on its custom chip targeting these variants, but it isn't yet reporting results back to customers.
Why isn't it reporting back? If you'd asked me a couple of months ago, I'd say the motivation was probably to avoid the regulatory hassles associated with testing overtly clinical markers - but the company's willingness to provide results for large-effect variants associated with breast cancer pretty much rules that out.
Instead, the most likely reason to hold back on giving results back to consumers is (perfectly reasonable) caution about the reliability of the test. Screening for extremely rare variants is tricky for two reasons: firstly, since there are very few individuals around who carry the mutation, obtaining positive controls is difficult; and secondly, screening accuracy needs to be extremely high to keep down the rate of false positives.
To illustrate that last point, let's say there was a genetic variant with a population frequency of just 0.1% (1 in every 1000 people carry it)*. Now, let's say you have a test with false positive and false negative rates of just 1 in every 1000 tests, and you run that test on one million people. Of the 1000 carriers in the population, the test will only miss one; but it will also give a positive result for 999 people who are non-carriers. In other words, even for this extremely accurate hypothetical test, only 50% of the people who test positive are actually carriers.
This means that testing for rare variants requires exceptionally high standards of accuracy, probably higher than could reasonably be expected from chip-based assays. Given the risks of reporting potentially unreliable results back to customers for serious risk variants it makes good sense for 23andMe to hold off until it has developed extra assays for quality control; and it's unlikely to do this until it has seen at least a few customers who actually do test positive for the variant in question.
As for obtaining samples from real carriers to enable the development of validation assays: what better way to do that than to recruit 10,000 customers suffering from Parkinson's? Targeted recruitment of customers with other diseases will no doubt follow.
It is now abundantly clear that 23andMe is intent on moving into the overtly clinical domain; Navigenics' purchase of its Affymetrix testing lab and deCODE's move into disease-specific genetic tests are other signs that this is a shift that will involve the entire personal genomics industry.
Personal genomics is getting serious.
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