(WebMD)
http://www.cbsnews.com/stories/2008/08/28/health/webmd/main4394326.shtml?source=RSSattr=HOME_4394326
Treadmill exercise may improve stroke survivors' walking ability by rewiring parts of the brain, according to a new study. The study also shows treadmill exercise may be better than stretching, the traditional exercise prescribed after a stroke, both for walking and overall fitness.
Researchers at the University of Maryland and Baltimore Veterans Affairs Medical Center compared 37 patients who performed "progressive task repetitive treadmill therapy" with 34 patients who did stretching. The patients had chronic hemiparesis, which is weakness on one side of the body, at least six months after a stroke. The patients had all completed conventional rehabilitation. The treadmill group was given the goal of three 40-minute sessions per week on the treadmill at 60 percent of their heart rate reserve. They started out slower, adding duration and intensity every two weeks. The exercise program lasted six months. The stretching group had the same number of sessions, and the length of each session was also the same. They performed a variety of traditional stretches on a raised mat table with the assistance of an instructor.
Researchers measured results in three ways: by looking at brain activity on MRIs, by measuring walking ability, and by evaluating overall fitness level.
The treadmill group performed better in all three categories. Treadmill participants increased their activity in certain parts of the brain by 72 percent on imaging tests. Brain activity changes did not occur in patients who did stretching exercise. Researchers checked brain MRIs while participants did knee-flexing exercises that mimic walking. The MRIs showed increased blood oxygenation and flow in the brain stem and cerebellum of the stroke survivors who had used the treadmill but not in those who did stretching.
Researchers say the increases in blood oxygenation and flow indicated that the cerebellum and brain stem had been "recruited" to replace some of the walking functions of the cortical brain that had been damaged by the strokes. "We saw what we call an equivalent of neuroplasticity - a change in brain activation that reflects the brain's adaptability," says Andreas Luft, MD, in a news release. Luft is one of the study's lead authors and a professor of clinical neurology and neurorehabilitation in the department of neurology at the University of Zurich, Switzerland.
The treadmill group also increased their walking speed and their fitness more than those in the stretching group. This is particularly important because stroke survivors' immobility can lead to cardiovascular disease and diabetes. In the study, published in Stroke: Journal of the American Heart Association, the authors argue that treadmill exercise should be included in long-term therapy programs for stroke survivors. "It is promising that treadmill exercise can stimulate new or underused brain circuits and improve walking in stroke survivors even after completion of conventional rehabilitation therapy," Luft says.
By Caroline WilbertReviewed by Elizabeth Klodas
Thursday, September 18, 2008
Connection between Brain and Physical fitness
Brain and Mind Fitness News
Brain Weightlifting: More Weight, Less Memory – Connections Between Physical and Brain Fitness
October 11, 2006
A recently published study in the journal Neurology shows that people who were tested cognitively at age 11 in 1932 and were tested again almost 70 years later showed better cognitive function if they were in good physical shape. “The important result of the study is that fitness contributes to better cognitive ability in old age,” according to psychologist Ian J. Deary, Ph.D., of the University of Edinburgh. “Thus, two people starting out with the same IQ at age 11, the fitter person at age 79 will, on average, have better cognitive function.”
In a separate study published by The American Academy of Neurology, researchers found the corollary that “a higher BMI was associated with lower cognitive test scores. Results from a test involving word memory recall show people with a BMI of 20 remembered an average of nine out of 16 words, while people with a BMI of 30 remembered an average of seven out of 16 words.”
They did not, however, find a correlation between a change in BMI and a change in cognitive performance, according to epidemiologist Maxime Cournot, M.D. of Toulouse University Hospital.
Take-Home Points
Managing obesity in middle-aged adults might help reduce dementia later. John Gunstad, PhD, an assistant professor of psychology at Kent State University in Kent, Ohio says “We’ve known [for many years] that obesity is linked to high blood pressure and other problems. The fact that its impact on brain function may be independent [of other problems] is newer.”
It’s never too late to get your brain or your body in shape.
Physical Fitness – Brain Fitness – Social Fitness … they are all interconnected and essential to your general wellbeing.
Brain Weightlifting: More Weight, Less Memory – Connections Between Physical and Brain Fitness
October 11, 2006
A recently published study in the journal Neurology shows that people who were tested cognitively at age 11 in 1932 and were tested again almost 70 years later showed better cognitive function if they were in good physical shape. “The important result of the study is that fitness contributes to better cognitive ability in old age,” according to psychologist Ian J. Deary, Ph.D., of the University of Edinburgh. “Thus, two people starting out with the same IQ at age 11, the fitter person at age 79 will, on average, have better cognitive function.”
In a separate study published by The American Academy of Neurology, researchers found the corollary that “a higher BMI was associated with lower cognitive test scores. Results from a test involving word memory recall show people with a BMI of 20 remembered an average of nine out of 16 words, while people with a BMI of 30 remembered an average of seven out of 16 words.”
They did not, however, find a correlation between a change in BMI and a change in cognitive performance, according to epidemiologist Maxime Cournot, M.D. of Toulouse University Hospital.
Take-Home Points
Managing obesity in middle-aged adults might help reduce dementia later. John Gunstad, PhD, an assistant professor of psychology at Kent State University in Kent, Ohio says “We’ve known [for many years] that obesity is linked to high blood pressure and other problems. The fact that its impact on brain function may be independent [of other problems] is newer.”
It’s never too late to get your brain or your body in shape.
Physical Fitness – Brain Fitness – Social Fitness … they are all interconnected and essential to your general wellbeing.
Can food improve brain function?
by Pascale Michelon, Ph. D
http://www.sharpbrains.com/blog/2008/09/08/can-food-improve-brain-health/
In other words, may some foods be specifically good for brain function?
For a great in-depth review of the effects of food on the brain you can check out Fernando Gomez-Pinilla’s recent article in Nature Reviews Neuroscience (reference below). Here is an overview of the state off the research.
Several components of diet seem to have a positive effect on brain function.
Omega-3 fatty acids
These acids are normal constituents of cell membranes and are essential for normal brain function. Omega-3 fatty acids can be found in fish (salmon), kiwi, and walnuts. Docosahexaenoic acid, or DHA, is the most abundant omega-3 fatty acid in cell membranes in the brain. The human body produces DHA but not enough. So we are dependent on the DHA that we get from what we eat.
A randomized double-blind controlled trial (which means seriously conducted scientific study) is currently looking at the effect of taking omega-3 fatty acids on children’s performance at school in England. Preliminary results (Portwood, 2006) suggest that the group of children who received omega-3 fatty acids showed some level of improvement in school performance compared to the group of children who received a placebo. More research is needed to confirm these results but they look promising.
Fatty acids are also regarded as a promising but untested treatment as mood stabilizer. Hibbeln (1998) showed a negative correlation between fish consumption (i.e., omega-3 fatty acid intake) and major depression in many countries including the United States, Canada, Germany and France. A negative correlation means that as consumption of omega-3 decreases, the prevalence of major depression increases. Note that a correlation does not imply causation: we cannot conclude that low omega-3 consumption causes major depression.
Folic acid (or folate)
Folate is generated by the liver, after the intestine has absorbed vitamin B. It is found in spinach, orange juice and yeast. Adequate levels of folate are essential for brain function.
Corrada and colleagues (2005) have shown that people who take more folate than others have less risks of developing Alzheimer’s disease. Note again that this is a correlation so more research is needed to determine whether folate is indeed responsible for the risk reduction.
Flavonoids
These are found in cocoa, green tea, Ginko biloba tree, citrus fruits, wine and dark chocolate. The antioxidant effects of flavonols have been shown in vitro (in the test tube) but more research is needed to establish the effects of flavonols in vivo (in a living organism). So far, Ginko biloba extracts have been shown to reduce memory impairment in mice…with mixed effects in humans, at best.
Antioxidant foods
The brain is highly susceptible to oxidative damage. This is why antioxidant food has become popular for their positive effects on brain function.
Antioxidants are found in a variety of food: Alpha lipoic is found in spinach, broccoli and potatoes; Vitamin E is found in vegetable oils, nuts, green leafy vegetables; Curcumin is found in the curry spice; Vitamin C is found in citrus fruit and several plants and vegetables. Berries are well known for their antioxidant capacity but it is not clear which of their many components has an effect on cognition.
Guts and the brain
We have seen that what we eat can affect brain function. Interestingly, it has also been shown that guts hormones themselves can directly influence brain function. Indeed, several gut hormones such as leptin (which sends signals to the brain to reduce appetite), ghrelin (which acts as an appetite stimulant) or insulin (which is secreted by the anticipation of meals and during digestion) have been found to enhance memory formation through their action on the hippocampus. As you know, the hippocampus is one of the brain structures crucial for spatial learning and memory formation. These gut hormones have an effect on the plasticity (the ability to change) of the connections between neurons in the hippocampus. For instance ghrelin promotes the formation of new synapse during learning. Insulin can enter the brain and interact directly with cells in the hippocampus.
Final note of caution
Please note that most of the studies showing positive effects of all these nutrients on the brain have been conducted in mice. A few human studies are now published but more research is clearly needed to establish and understand the effects of specific foods on brain function.
http://www.sharpbrains.com/blog/2008/09/08/can-food-improve-brain-health/
In other words, may some foods be specifically good for brain function?
For a great in-depth review of the effects of food on the brain you can check out Fernando Gomez-Pinilla’s recent article in Nature Reviews Neuroscience (reference below). Here is an overview of the state off the research.
Several components of diet seem to have a positive effect on brain function.
Omega-3 fatty acids
These acids are normal constituents of cell membranes and are essential for normal brain function. Omega-3 fatty acids can be found in fish (salmon), kiwi, and walnuts. Docosahexaenoic acid, or DHA, is the most abundant omega-3 fatty acid in cell membranes in the brain. The human body produces DHA but not enough. So we are dependent on the DHA that we get from what we eat.
A randomized double-blind controlled trial (which means seriously conducted scientific study) is currently looking at the effect of taking omega-3 fatty acids on children’s performance at school in England. Preliminary results (Portwood, 2006) suggest that the group of children who received omega-3 fatty acids showed some level of improvement in school performance compared to the group of children who received a placebo. More research is needed to confirm these results but they look promising.
Fatty acids are also regarded as a promising but untested treatment as mood stabilizer. Hibbeln (1998) showed a negative correlation between fish consumption (i.e., omega-3 fatty acid intake) and major depression in many countries including the United States, Canada, Germany and France. A negative correlation means that as consumption of omega-3 decreases, the prevalence of major depression increases. Note that a correlation does not imply causation: we cannot conclude that low omega-3 consumption causes major depression.
Folic acid (or folate)
Folate is generated by the liver, after the intestine has absorbed vitamin B. It is found in spinach, orange juice and yeast. Adequate levels of folate are essential for brain function.
Corrada and colleagues (2005) have shown that people who take more folate than others have less risks of developing Alzheimer’s disease. Note again that this is a correlation so more research is needed to determine whether folate is indeed responsible for the risk reduction.
Flavonoids
These are found in cocoa, green tea, Ginko biloba tree, citrus fruits, wine and dark chocolate. The antioxidant effects of flavonols have been shown in vitro (in the test tube) but more research is needed to establish the effects of flavonols in vivo (in a living organism). So far, Ginko biloba extracts have been shown to reduce memory impairment in mice…with mixed effects in humans, at best.
Antioxidant foods
The brain is highly susceptible to oxidative damage. This is why antioxidant food has become popular for their positive effects on brain function.
Antioxidants are found in a variety of food: Alpha lipoic is found in spinach, broccoli and potatoes; Vitamin E is found in vegetable oils, nuts, green leafy vegetables; Curcumin is found in the curry spice; Vitamin C is found in citrus fruit and several plants and vegetables. Berries are well known for their antioxidant capacity but it is not clear which of their many components has an effect on cognition.
Guts and the brain
We have seen that what we eat can affect brain function. Interestingly, it has also been shown that guts hormones themselves can directly influence brain function. Indeed, several gut hormones such as leptin (which sends signals to the brain to reduce appetite), ghrelin (which acts as an appetite stimulant) or insulin (which is secreted by the anticipation of meals and during digestion) have been found to enhance memory formation through their action on the hippocampus. As you know, the hippocampus is one of the brain structures crucial for spatial learning and memory formation. These gut hormones have an effect on the plasticity (the ability to change) of the connections between neurons in the hippocampus. For instance ghrelin promotes the formation of new synapse during learning. Insulin can enter the brain and interact directly with cells in the hippocampus.
Final note of caution
Please note that most of the studies showing positive effects of all these nutrients on the brain have been conducted in mice. A few human studies are now published but more research is clearly needed to establish and understand the effects of specific foods on brain function.
Sunday, September 14, 2008
Guidelines Updated for Diagnosis and Treatment of Rhinitis
News Author: Laurie Barclay, MD
CME Author: Laurie Barclay, MD
August 18, 2008 —The Joint Task Force on Practice Parameters, representing the American Academy of Allergy, Asthma & Immunology; the American College of Allergy, Asthma and Immunology; and the Joint Council of Allergy, Asthma and Immunology have issued updated guidelines for the diagnosis, management, and treatment of rhinitis. The updated recommendations are published in the August issue of the Journal of Allergy and Clinical Immunology.
"Rhinitis is characterized by 1 or more of the following symptoms: nasal congestion, rhinorrhea (anterior and posterior), sneezing, and itching," write Dana V. Wallace, MD, from Nova Southeastern University in Davie, Florida, and colleagues from the Joint Task Force on Practice Parameters. "Rhinitis is usually associated with inflammation, but some forms of rhinitis such as vasomotor rhinitis or atrophic rhinitis are not predominantly inflammatory. Rhinitis frequently is accompanied by symptoms involving the eyes, ears, and throat."
Key updates included in these guidelines are as follows:
- Pharmacologic products that have become available since publication of the previous 1998 guidelines on diagnosis and management of rhinitis are reviewed.
- On the basis of more recent evidence, positioning of agents used in management, such as leukotriene receptor antagonists (LTRA), is better defined.
- The term episodic is introduced referring to rhinitis brought about by sporadic exposures to inhalant aeroallergens, and implications for treatment of episodic rhinitis are discussed.
- Certain agents, namely intranasal corticosteroids (INS), are recommended for use on an as-needed basis.
- The importance of recognizing comorbidities of allergic rhinitis (AR) is emphasized. These include asthma, sinusitis, and obstructive sleep apnea. Also highlighted is the importance of conducting appropriate studies, such as pulmonary function testing and sleep apnea studies.
- Evidence regarding use of combination therapy is reviewed, particularly the use of LTRA with antihistamines.
- The updated guidelines highlight the need to consider the benefits vs recently raised safety concerns regarding oral decongestants before using them in children younger than 6 years of age.
- It is now recommended that second-generation antihistamines be considered as safe agents for use during pregnancy.
- INS may be used for symptoms of allergic conjunctivitis associated with rhinitis.
- Use of a Rhinitis Action Plan should be considered.
- Recently available and emerging diagnostic and surgical procedures, including acoustic rhinometry and radiofrequency volumetric tissue reduction, are reviewed.
The main pharmacotherapeutic options for AR are as follows:
- When used continuously, oral antihistamines, or oral H1-receptor antagonists, are most effective for seasonal AR and perennial AR, but their relatively rapid onset of action also makes them appropriate for as-needed use in episodic AR.
- Oral antihistamines are less effective for nasal congestion vs other nasal symptoms, and other options are generally preferred for more severe AR. For AR, oral antihistamines are less effective for AR vs INS, but they are similarly effective to INS for associated ocular symptoms.
- Oral antihistamines are typically ineffective for non-AR, resulting in other choices being better for mixed rhinitis.
- Second-generation oral antihistamines are usually preferred over first-generation antihistamines to minimize sedation, performance impairment, and anticholinergic effects. At recommended doses, the second-generation oral antihistamines fexofenadine, loratadine, and desloratadine do not cause sedation.
- Oral corticosteroids may be appropriate for very severe nasal symptoms when given as a short course (5 - 7 days) and are preferred to single or repeated administration of intramuscular corticosteroids, which should be discouraged.
- Oral decongestants include pseudoephedrine, which reduces nasal congestion, although adverse effects include insomnia, irritability, palpitations, and hypertension.
- Of the LTRA, montelukast is approved for seasonal AR and perennial AR, and adverse effects are minimal. However, with loratadine as the usual comparator, LTRA have not been shown to have significantly different efficacy from oral antihistamines. Because LTRA are approved for both rhinitis and asthma, they may be considered in patients who have both conditions.
- Intranasal antihistamines are effective for both seasonal AR and perennial AR. Their clinically significant, rapid onset of action also makes them suitable for as-needed use in episodic AR. Although their efficacy for AR is as good as or better than oral second-generation antihistamines, with a clinically significant effect on nasal congestion, they are not as effective as INS for nasal symptoms. Because they are also approved for vasomotor rhinitis, they are a suitable option for patients with mixed rhinitis. The adverse effects of intranasal azelastine are a bitter taste and somnolence.
- Intranasal anticholinergic (ipratropium) has a rapid onset of action and is therefore appropriate for episodic rhinitis. Although it reduces rhinorrhea, it is ineffective for other symptoms of seasonal AR and perennial AR. There may be dryness of nasal membranes, but adverse effects are otherwise minimal.
- INS are the most effective monotherapy for seasonal AR and perennial AR because of their efficacy for all symptoms of seasonal AR and perennial AR, including nasal congestion. As-needed use of INS may be effective for seasonal AR and may also be considered in patients with episodic AR. The typical onset of action is within 12 hours, which is less rapid than with oral or intranasal antihistamines, but symptom relief may begin within 3 to 4 hours in some patients.
- For seasonal AR and perennial AR, INS are more effective than combination therapy with oral antihistamine and LTRA. For associated ocular symptoms of AR, efficacy of INS is similar to that of oral antihistamines. INS are also a suitable option for mixed rhinitis, because agents in this class are also effective for some non-AR. INS do not have significant systemic adverse effects in adults, and when used at recommended doses, they have not been shown to cause growth suppression in children with perennial AR. Local adverse effects are minimal, but nasal irritation and bleeding occur, and nasal septal perforation has rarely been reported.
- Intranasal cromolyn may be useful for maintenance treatment of AR. The onset of action is within 4 to 7 days, but the full benefit may not be evident for weeks. Administration just before allergen exposure for episodic rhinitis protects against the allergic response for 4 to 8 hours. Intranasal cromolyn is not as effective as INS, and data are insufficient to compare INS with LTRA and antihistamines.
"Initial treatment of nonsevere rhinitis may include single-agent or combination pharmacologic therapy and avoidance measures," the guidelines authors conclude. "Oral antihistamines are generally effective in reducing rhinorrhea, sneezing, and itching associated with allergic rhinitis but have little objective effect on nasal congestion."
J Allergy Clin Immunol. 2008;122:S1-S84.
Rhinitis Often Accompanies Hard-to-Control Asthma
News Author: David Douglas
CME Author: Charles Vega, MD
May 2, 2008;
As senior investigator Dr. Alvaro A. Cruz told Reuters Health, "this article reports on strong evidence for an association between moderate-to-severe rhinitis and uncontrolled asthma."
Dr. Cruz, of Universidade Federal de Bahia, and colleagues also note that asthma and rhinitis share many similarities and the prevalence of rhinitis among asthmatics is high.
To further investigate the relationship between the conditions, the researchers prospectively studied 557 patients with severe asthma. In all, 31% had moderate to severe rhinitis, 54% had mild rhinitis and 15% had no rhinitis.
Compared to the other subjects, patients with moderate-to-severe rhinitis were more than 3 times as likely (odds ratio, 3.83) to visit the emergency room during a year of follow-up.
By the end of follow-up, they were also almost 3 times as likely (odds ratio, 2.94) to show a less than 10% improvement in airway obstruction and were more than 12 times as likely to have uncontrolled asthma.
The team found a positive correlation between the severity of rhinitis and severity of asthma, and a negative correlation with quality-of-life scores.
"Taking into consideration that the patients were receiving the best treatment options for asthma and rhinitis," Dr. Cruz said in conclusion, "the most likely explanation for the observed inter-relationship is that both rhinitis and asthma were manifestations of the same disease affecting the entire airway, for which the degree of severity of the upper and lower airway processes is correlated."
Allergy. 2008;63:564-569.
Reuters Health Information 2008. © 2008 Reuters Ltd.
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