Neurologic disorders Archives - Dr Amin Azhari - دکتر امین اظهری

Loss of motivation and Alzheimer’s disease progression

Researchers from Indiana University School of Medicine are studying why neuropsychiatric symptoms, such as apathy and irritability, appear in most Alzheimer’s disease patients before the onset of memory loss.

The study, led by Yao-Ying Ma, MD, PhD, assistant professor of pharmacology and toxicology, was recently featured in the publication Molecular Psychiatry.

The investigation focused on the nucleus accumbens, a critical brain region processing motivation. Located in the ventral striatum, this region is not studied much among Alzheimer’s disease researchers, Ma said; it’s mainly researched to understand motivational and emotional processes. Previous studies, Ma said, have shown that the volume of nucleus accumbens, like the cortical and hippocampal regions in the brain, is reduced in adults with Alzheimer’s disease.

Ma, who is relatively new to the field of Alzheimer’s disease research, has a background in drug addiction studies and synaptic communication—the process by which neurons talk to each other in the brain. Some of the neuropsychiatric symptoms among people who suffer from substance abuse—apathy, mood swings, anxiety—are also found in Alzheimer’s disease patients.

The investigation focused on the nucleus accumbens, a critical brain region processing motivation. Located in the ventral striatum, this region is not studied much among Alzheimer’s disease researchers, Ma said; it’s mainly researched to understand motivational and emotional processes. Previous studies, Ma said, have shown that the volume of nucleus accumbens, like the cortical and hippocampal regions in the brain, is reduced in adults with Alzheimer’s disease.

Ma, who is relatively new to the field of Alzheimer’s disease research, has a background in drug addiction studies and synaptic communication—the process by which neurons talk to each other in the brain. Some of the neuropsychiatric symptoms among people who suffer from substance abuse—apathy, mood swings, anxiety—are also found in Alzheimer’s disease patients.

These neuropsychiatric symptoms, however, tend to occur earlier than memory loss, but no effective treatments are available, Ma said. She emphasized that there is an urgent need to understand why those symptoms exist and how they correlate with cognitive deficits. Ma said this study identified synaptic calcium permeable receptors (CP-AMPARs) in the nucleus accumbens in an Alzheimer’s disease model. The receptor, which is normally absent in that part of the brain, gives permission for calcium to enter the neurons. This leads to an overload of calcium, which leads to a breakdown of its synaptic structure. In turn, calcium accumulation triggers a cascade of intracellular changes that can be lethal to the neuron by amplifying calcium overload via a positive feedback mechanism.

Release date: 25 April 2022
Source: Indiana University School of Medicine

Women may be less likely to go back to work after severe stroke

More than one-third of people who have a clot removed from a major blood vessel in the brain after a stroke return to work within three months, according to a new study from Germany. But women were half as likely to do so as men.

The study, published Thursday in the American Heart Association journal Stroke, found women and men were more likely to return to work if they were treated with a combination of mechanical blood clot removal and clot-busting medication to clear their clogged blood vessels than if they just had their clots removed.

When blood clots in the brain block a major artery, they can cause a severe stroke with the potential for serious disability, making it less likely people will return to work. Clot-caused ischemic strokes account for 87% of all strokes in the U.S. Blockages in large vessels account for 24%-46% of ischemic strokes. Stroke is the fifth-leading cause of death in the U.S. and a leading cause of disability.

Endovascular mechanical thrombectomy is a procedure that uses a slim catheter to remove a clot blocking a large blood vessel in the brain. This procedure, along with clot-busting medications, is considered standard practice for the treatment of some severe strokes.

Researchers analyzed data for 606 men and women, ages 18 to 64, in Germany who survived large vessel occlusion ischemic strokes between 2015 and 2019. Participants, all of whom worked prior to their strokes, were treated with a mechanical thrombectomy. A subset of 370 patients also received clot-busting medications. They compared those who went back to work 90 days after having a thrombectomy to those who did not return to work.

Release date: 21 April 2022
Source: American Heart Association

Covid-19, Neurologic disorders, Neurologic disorders, Neurologic disorders, Neurologic disorders, Neurologic disorders, Neurologic disorders, Neurologic disorders, Neurologic disorders, Neurologic disorders, Neurologic disorders

COVID-19 Pneumonia Increases Dementia Risk

A new study from the from the University of Missouri School of Medicine and MU Health Care shows patients hospitalized with COVID-19 pneumonia have a higher risk of developing dementia than those with other types of pneumonia.

A team of MU researchers pulled Cerner Real World Data from 1.4 billion medical encounters prior to July 31, 2021. They selected patients hospitalized with pneumonia for more than 24 hours. Among 10,403 patients with COVID-19 pneumonia, 312 (3%) developed new onset dementia after recovering, compared to 263 (2.5%) of the 10,403 patients with other types of pneumonia diagnosed with dementia.

Their study, “New Onset Dementia Among Survivors of Pneumonia Associated with Sevre Acute Respiratory Syndrome Coronavirus 2 Infection,” was recently published in the journal Open Forum Infectious Diseases. Part of the support for this study was provided by the National Institutes of Health. The content does not necessarily represent the official views of the funding agency. Qureshi has received consultation fees from AstraZeneca. The authors declare no other potential conflicts of interest.

Release date: 19 April 2022
Source: University of Missouri-Columbia

Antidepressants are not associated with improved quality of life in the long run

Among people with depression, those using antidepressants over the long term had no better physical or mental health. Over time, using antidepressants is not associated with significantly better health-related quality of life, compared to people with depression who do not take the drugs. These are the findings of a new study published this week in the open-access journal PLOS ONE by Omar Almohammed of King Saud University, Saudi Arabia, and colleagues.

It is generally well known that depression disorder has a significant impact on the health-related quality of life (HRQoL) of patients. While studies have shown the efficacy of antidepressant medications for treatment of depression disorder, these medications’ effect on patients’ overall well-being and HRQoL remains controversial.

In the new study, the researchers used data from the 2005-2015 United States’ Medical Expenditures Panel Survey (MEPS), a large longitudinal study that tracks the health services that Americans use. Any person with a diagnosis of depression disorder was identified in the MEPS files. Over the duration of the study, on average there were 17.47 million adult patients diagnosed with depression each year with two years of follow-up, and 57.6% of these received treatment with antidepressant medications.

Release date: 20 April 2022
Source: EurekAlert

Sport Medicine

Sitting Tai Chi exercises improved recovery outcomes for older stroke survivors

A study in China found that after three months of practicing a modified form of Tai Chi in which participants are seated, stroke survivors had improved hand and arm function, sitting balance, mental health and quality of life, compared to stroke survivors who participated in a standard stroke rehabilitation exercise program.
The study is the first randomized controlled trial to indicate practicing a seated form of Tai Chi early after a stroke enhanced health outcomes.
Stroke survivors who practiced a seated form of Tai Chi had equal or greater improvement in hand and arm strength, shoulder range of motion, balance control, symptoms of depression and activities of daily living after three months, compared to those who participated in a standard stroke rehabilitation exercise program, according to new research published today in Stroke, the peer-reviewed flagship journal of the American Stroke Association, a division of the American Heart Association.

The American Heart Association’s/American Stroke Association’s Guidelines for the Early Management of Patients with Acute Ischemic Stroke recommend people start stroke rehabilitation within seven days and continue for up to six months after a stroke. However, many survivors opt out of rehabilitation therapy because they lack physical stability or are unable to fully use their arms. The Association also notes in a Scientific Statement about Physical Activity and Exercise Recommendations for Stroke Survivors that flexibility and muscle strength training, including yoga and Tai Chi, are reported to be beneficial for stroke survivors in improving balance, quality of life and mental health, while reducing the fear of falling.

Tai Chi, a traditional Chinese martial art, consists of a series of slow, careful movements of the hands, arms, neck, legs and core combined with deep breathing. The novelty of this study is that researchers developed a sitting routine of Tai Chi exercises for people who had a recent ischemic stroke (blocked blood vessel to the brain) and experienced hand and arm weakness or partial paralysis.

Release date: 07 April 2022
Source: American Heart Association

Sport Medicine

Researchers discover new neurodevelopmental disorder

Australian researchers have discovered a new neurodevelopmental disorder after uncovering its link to a tumor suppressor gene.

The international research collaboration, led by the Murdoch Children’s Research Institute (MCRI) and published in The American Journal of Human Genetics, has linked a recognised tumor suppressor gene to a new neurodevelopmental syndrome, ending the diagnostic journey for 32 families around the world.

The study found variations in the FBXW7 gene were associated with the newly identified condition, which causes mild to severe developmental delay, intellectual disability, hypotonia and gastrointestinal issues.

Murdoch Children’s researcher Dr Sarah Stephenson said because the FBXW7 gene regulated the life-cycle of cells, cell growth and survival, the research team speculated that abnormal cell proliferation during brain development may underpin the broad spectrum of brain abnormalities identified in this new disorder.

The study used cutting-edge diagnostic tools, genomic sequencing and global data-sharing platforms to identify 35 people, aged 2-44 years, from 32 families in seven countries harbouring the FBXW7 gene, which had variants that were associated with the never-before described neurodevelopmental syndrome.

Almost all affected people had developmental delay and intellectual disability, ranging from borderline to severe, 62 per cent had decreased muscle tone, 46 per cent noted feeding difficulties and constipation and 23 per cent had seizures. Brain imaging also detailed variable underlying structural differences affecting the cerebellum, nerve fibres and white matter.

The team then reduced the gene’s levels in a fly model, which affected the flies’ ability to jump in response to a stimulus. This supported the observation that the 28 variants in FBXW7 were the cause of the condition. It also further cemented the fundamental role of the gene in development broadly, and the brain, specifically.

Release date: 08 April 2022
Source: Murdoch Childrens Research Institute

Musculoskeletal diseases

Cell Treatment Slows Disease in Duchenne Muscular Dystrophy Patients

Cell Therapy Developed by Smidt Heart Institute Leader Delays Disease Progression in Patients Who Have Few Treatment Options
A cell therapy developed by the executive director of the Smidt Heart Institute stabilizes weakened muscles–including the heart muscle–in Duchenne muscular dystrophy patients, a new study published in the international peer-reviewed journal The Lancet shows.

If the HOPE-2 study’s success is duplicated in the upcoming multicenter, randomized, placebo-controlled HOPE-3 clinical trial, the intravenous cell therapy could become the first Food and Drug Administration-approved treatment for Duchenne patients with advanced disease.

“This therapy is unique in that it addresses two vital needs in patients with Duchenne: physical movement and a healthy heart,” said Eduardo Marbán, MD, PhD, executive director of the Smidt Heart Institute at Cedars-Sinai, the Mark S. Siegel Family Foundation Distinguished Professor, an author on the study and the inventor of cardiosphere-derived cells (CDCs), progenitor cells derived from human heart tissue, which have been used in multiple clinical trials.

Duchenne muscular dystrophy is a rare, inherited disorder that mostly affects males. It’s caused by mutations on a gene on the X chromosome that interferes with the production of a protein called dystrophin that muscles need to function. Children born with such mutations have muscle weakness throughout their bodies. This makes it difficult for them to do normal activities like run, jump, climb stairs, stand up after sitting and pedal a bicycle. They can also become extremely sick when muscles in their hearts and respiratory organs weaken.

The prognosis for patients with Duchenne muscular dystrophy is bleak. Most use a wheelchair by the time they are teenagers and don’t typically live into their 30s. There is no cure for the disease. Currently, the only approved medical treatments are aimed at delaying loss of the ability to walk; nothing is available for patients with more advanced disease, who now outnumber those with milder symptoms.

Release date: 10 March 2022
Source: Cedars-Sinai Medical Center

Reproductive factors and dementia risk

Certain events related to shorter estrogen exposure may be associated with increased dementia risk.

Pregnancy, long reproductive span, and older age at menopause are associated with a lower risk of dementia in women, according to a study publishing April 5th in the open access journal PLOS Medicine. Inversely, hysterectomy, younger age of first birth, and younger or older than average age at first period were associated with greater dementia risk. The study suggests that reproductive and hormonal factors may be involved in dementia risk, but observed a similar association between the number of children and dementia risk in women and men, suggesting that the physical experience of childbearing may not account for risk variation.

Dementia rates are increasing around the world, with some studies reporting a higher incidence in women than men, yet there is a limited evidence base on reproductive factors and the risk of dementia. Jessica Gong at The George Institute for Global Health, Australia, and colleagues used data from the UK Biobank to examine the risk of all cause dementia and reproductive factors in 273,240 women as well as the number of children in those women and in 228,965 men.

After controlling for age, socioeconomic status, smoking, body mass index (BMI), and other elements, certain events related to shorter cumulative exposure to internally produced estrogen – such as older than average age at first period, younger than average age at menopause, and having a hysterectomy – were associated with higher dementia risk. Pregnancy, even aborted pregnancy, longer reproductive span, older age at menopause, and use of contraceptive pills were associated with a lower risk of all-cause dementia. For both men and women, compared with having two children, having no children or four or more were apparently associated with greater risk of dementia.

The study has limitations including the retrospective reporting on reproductive factors that can be subject to bias, and the fact that UK Biobank is a relatively healthy cohort of affluent people of white British ancestry so may not be representative of a broader population.

Release date: 05 April 2022
Source: EurekAlert

Loss of Neurons, Not Lack of Sleep, Makes Alzheimer’s Patients Drowsy

The lethargy that many Alzheimer’s patients experience is caused not by a lack of sleep, but rather by the degeneration of a type of neuron that keeps us awake, according to a study that also confirms the tau protein is behind that neurodegeneration.

The study’s findings contradict the common notion that Alzheimer’s patients sleep during the day to make up for a bad night of sleep and point toward potential therapies to help these patients feel more awake.

The data came from study participants who were patients at UC San Francisco’s Memory and Aging Center and volunteered to have their sleep monitored with electroencephalogram (EEG) and donate their brains after they died.

Being able to compare the study participants’ sleep data with microscopic views of their post-mortem brain tissue was the key to answering a question that scientists have been pondering for years.

The opposite phenomenon occurs in patients with other neurodegenerative conditions, such as progressive supranuclear palsy (PSP), who were also included in the study. Those patients have damage to the neurons that make them feel tired, so they are unable to sleep and become sleep deprived.

Release date: 04 April 2022
Source: University of California – San Francisco

Air pollution linked to depressive symptoms in adolescents

Exposure to ozone from air pollution has been linked to an increase in depressive symptoms for adolescents over time, even in neighborhoods that meet air quality standards, according to new research published by the American Psychological Association.

Ozone is a gas that is produced when various pollutants from motor vehicle exhaust, power plants and other sources react to sunlight. Higher ozone levels have been linked to various physical ailments, including asthma, respiratory viruses and premature death from respiratory causes. This study is the first to link ozone levels to the development of depression symptoms symptoms in adolescents over time. Those symptoms may include persistent feelings of sadness or hopelessness, difficulty with concentration, sleep disturbances and thoughts about suicide.

Adolescents who lived in areas with relatively higher ozone levels showed significant increases in depressive symptoms over time, even though the ozone levels in their neighborhoods didn’t exceed state or national air quality standards. The findings weren’t affected by the participants’ sex, age, race, household income, parental education or socioeconomic characteristics of their neighborhoods. The research was published online in Developmental Psychology.

Release date: 14 March 2022
Source: American Psychological Association