(Press-News.org) Researchers in the Department of Neurology at Tohoku University, which is led by professor Masashi Aoki, have developed a classification scheme for neuromyelitis optica spectrum disorder, a rare autoimmune disease that until recently was thought to be a type of multiple sclerosis (MS). The new taxonomy for the disease replaces one borrowed from MS but which was inappropriate for what is in fact a distinct condition.
An autoimmune disease, neuromyelitis optica spectrum disorder (NMOSD), was for a long time thought to be a type of multiple sclerosis (MS), but it has recently been identified as an entirely different illness. As a result of this confusion, identification of NMOSD suffered from a clinical classification scheme borrowed from MS but is inappropriate due to its unique characteristics. A new classification scheme that focuses instead on the degree of deterioration of astrocytes, a specialized central nervous system cell involved in repair processes, has now been developed.
A paper by Yoshiki Takai and Tatsuro Misu at Department of Neurology, Tohoku University, describing the new classification scheme appears online in the journal Brain on March 12.
NMOSD is a rare but serious illness also known as Devic's disease that produces an inflammation of the spinal cord (myelitis) and optic nerve (optic neuritis) that can lead to blindness and paralysis. Similar to multiple sclerosis, the disorder produces a deterioration of myelin, the fatty layer around neurons that insulates them and allows their electrical impulses to be rapidly transmitted. Deterioration of the myelin slows down or even inhibits this transmission of nerve signals.
As a result of this similarity, NMOSD was long thought to be a sub-type of multiple sclerosis. But NMOSD has recently been identified as a distinct autoimmune illness with more severe symptoms than MS and with a separate set of causes. The demyelinating process in NMOSD is only a product of a newly identified and more fundamental disease process: astrocytopathy, or destruction of astrocytes. These specialized and star-shaped central nervous system cells perform a range of functions, including delivery of nutrients to nervous tissue, regulation of blood flow in the brain, and repair processes after injury or infection.
However, the two diseases, MS and NMOSD, remain difficult for clinicians to distinguish especially in the early stages because both illnesses produce optic neuritis and myelitis.
As a result of this confusion between the two illnesses, up to now, diagnosis of NMOSD has used the same disease classification system as MS, which depends upon the degree of demyelination.
"There was no disease classification system unique and appropriate to this distinct disease," said Yoshiki Takai of the Department of Neurology at Tohoku University. "So we decided to come up with one ourselves."
The researchers developed an NMOSD classification scheme that depends not on the degree of demyelination but instead upon differences in the morphology (in essence the shape) of astrocyte degeneration.
This astrocyte degeneration comes in four main types that the researchers have named astrocyte lysis, progenitor, protoplasmic gliosis, and fibrous astrogliosis, each with their own set of characteristic markers identifiable from astrocyte lesions, or damage to the astrocytes. Astrocyte lysis, or extensive loss or complete destruction of astrocytes, a characteristic of the most acute type of such damage (meaning sudden onset and short duration), is a feature highly specific to NMOSD. The other three types describe subacute or chronic forms of the disease (meaning slow onset that can worsen over time).
The classification scheme is the first taxonomy of astrocytopathy to be published.
The researchers hope that in both clinical practice and experimental study, this classification scheme will be used as the standard for all astrocyte-related disease mechanisms both for NMOSD and across the fields of neurodegenerative diseases and neuron regeneration.
INFORMATION:
Hamilton, ON (April 14, 2021) - Modified immune cells that ruthlessly kill cancerous tumours may prove a game-changer for people living with late-stage cancer.
McMaster University researchers Ali Ashkar and Sophie Poznanski have uncovered that changing the metabolism of natural killer (NK) immune cells allows these cells to overcome the hostile conditions found inside tumours and destroy advanced ovarian and lung cancer.
In the past decade cancer immunotherapy has achieved tremendous therapeutic effects in patient with blood cancers. However, the immunosuppressive conditions found inside solid tumours, whose aggressive growth starves surrounding healthy tissues of energy, have ...
BOSTON - Approximately one in four patients hospitalized for the acute respiratory distress syndrome (ARDS) associated with severe COVID-19 infections may have a distinct phenotype (disease presentation) or biochemical profile associated with organ dysfunction, blood-clotting abnormalities and greater risk of death than patients with other, seemingly similar forms of the disease, researchers at Massachusetts General Hospital (MGH) have found.
Among 263 patients admitted to intensive care units (ICUs) at MGH for respiratory failure due to severe COVID-19 infection, 70 (26.6%) had increased ...
WASHINGTON, April 15, 2021 -- Some snake species slither across the ground, while others climb trees, dive through sand or glide across water. Today, scientists report that the surface chemistry of snake scales varies among species that negotiate these different terrains. The findings could have implications for designing durable materials, as well as robots that mimic snake locomotion to cross surfaces that would otherwise be impassable.
The researchers will present their results today at the spring meeting of the American Chemical Society (ACS). ACS Spring 2021 is being held online April 5-30. Live sessions will be hosted April 5-16, and on-demand and networking ...
DALLAS, April 15, 2021 - Maintenance of good oral health is more important than use of antibiotics in dental procedures for some heart patients to prevent a heart infection caused by bacteria around the teeth, according to a new American Heart Association (AHA) scientific statement published today in the association's flagship journal, Circulation.
Infective endocarditis (IE), also called bacterial endocarditis, is a heart infection caused by bacteria that enter the bloodstream and settle in the heart lining, a heart valve or a blood vessel. It is uncommon, ...
Researchers at the University of Zurich show that increased sensitivity in a specific region of the brain contributes to the development of anxiety and depression in response to real-life stress. Their study establishes an objective neurobiological measure for stress resilience in humans.
Some people don't seem to be too bothered when it comes to handling stress. For others, however, prolonged exposure to stress can lead to symptoms of anxiety and depression. While stress resilience is a widely discussed concept, it is still very challenging to predict people's ...
Technologies to remove CO2 from the atmosphere, such as reforestation or bioenergy with carbon capture and storage (BECCS), are an indispensable part in most scenarios to limit climate change. However, excessive deployment of such technologies would carry risks such as land conflicts or enhanced water scarcity due to a high demand for bioenergy crops. To tackle this trade-off, a team of researchers from Potsdam and Berlin has now identified requirements for a dynamic, long-term carbon price pathway to reduce the demand for CO2 removal technologies and thus effectively limit long-term ...
ROCHESTER, Minn. - Though researchers have long known that several physiological and anatomical changes occur during pregnancy that can contribute to kidney stone formation, evidence of the link has been lacking. But now Mayo Clinic researchers believe they have that evidence.
An observational study that reviewed the medical records for nearly 3,000 female patients from 1984 to 2012 finds that pregnancy increases the risk of a first-time symptomatic kidney stone. The risk peaks close to delivery and then improves by one year after delivery, though a modest risk of developing kidney stones continues beyond ...
The COVID-19 disease due to infection by the SARS-CoV2 virus has changed the behavior patterns of humanity by becoming a pandemic of international scope. To date, more than 136 million people have suffered from the disease and more than 2.9 million of them have lost their lives. It is important to remember that the symptoms of the infection vary widely in the population, from individuals who do not present any symptoms to those who need admission to intensive care units with emergency assisted ventilation. It is largely unknown what factors are responsible for this range of very ...
Sophia Antipolis - 15 April 2021: An observational study in nearly 20,000 individuals has found that greater intake of red and processed meat is associated with worse heart function. The research is presented at ESC Preventive Cardiology 2021, an online scientific congress of the European Society of Cardiology (ESC).1
"Previous studies have shown links between greater red meat consumption and increased risk of heart attacks or dying from heart disease," said study author Dr. Zahra Raisi-Estabragh of Queen Mary University of London, UK.2,3 "For the first time, we ...
More than 30 years ago, wilderness areas - natural areas that have not been considerably modified by humans - were identified as priorities of conservation and protection actions. Only recently has there been a push to define how to measure wilderness, with a focus on intact habitats. The integrity of natural ecosystems has also been recognized by the UN Convention on Biological Diversity as an important goal in the post-2020 global biodiversity framework. "We know intact habitat is increasingly being lost and the values of intact habitat have been demonstrated for both biodiversity and people," says Dr Andrew Plumptre from the Key Biodiversity Areas Secretariat in Cambridge, ...