#BrainStem

[er-cryptid]

[thelovebudllc]

New auditory brainstem implant shows promise for patients with Neurofibromatosis type 2

A new study co-led by Mass General Brigham researchers points to a promising new type of auditory brainstem implant (ABI) that could benefit people who are deaf due to Neurofibromatosis type 2 (NF2) and other severe inner ear abnormalities that prevent them from receiving cochlear implants. With further tests and trials, researchers hope it will provide a more effective treatment alternative than…

[blueoaknx]

Mitochondrial Dysfunction in Leigh Syndrome

Introduction:-

Leigh Syndrome (LS) is a rare, severe neurological disorder that typically manifests in infancy or early childhood. It is primarily caused by mitochondrial dysfunction, which results in progressive neurodegeneration. This condition affects approximately 1 in 40,000 newborns and is characterized by lesions in the brainstem and basal ganglia, leading to motor and cognitive impairments.

Pathophysiology of Leigh Syndrome

Mitochondrial dysfunction is central to the pathology of Leigh Syndrome. The mitochondria, often referred to as the powerhouse of the cell, generate adenosine triphosphate (ATP) through oxidative phosphorylation (OXPHOS). This process occurs within the electron transport chain (ETC), which consists of five protein complexes embedded in the inner mitochondrial membrane. In LS, genetic mutations disrupt these complexes, impairing ATP production and causing an accumulation of toxic byproducts such as reactive oxygen species (ROS) and lactate.

The most frequently affected complexes in Leigh Syndrome are Complex I (NADH: ubiquinone oxidoreductase) and Complex IV (cytochrome c oxidase). Mutations in nuclear or mitochondrial DNA (mtDNA) encoding subunits of these complexes lead to decreased enzymatic activity, impairing energy production. As neurons have high energy demands, they are particularly vulnerable to mitochondrial defects, resulting in neuronal cell death and progressive neurodegeneration.

Genetic and Biochemical Basis

Leigh Syndrome is genetically heterogeneous, with over 75 known causative genes. Mutations can be inherited in an autosomal recessive, X-linked, or maternal manner, depending on whether the affected gene is in nuclear DNA or mtDNA. Some of the most common mutations occur in:

MT-ND genes (affecting Complex I)

SURF1 gene (associated with Complex IV deficiency)

PDHA1 gene (disrupting pyruvate dehydrogenase complex, leading to lactic acidosis)

Mitochondrial DNA mutations are maternally inherited, while nuclear DNA mutations follow Mendelian inheritance patterns. The variability in genetic origins contributes to the clinical heterogeneity observed in Leigh Syndrome.

Impact on the Nervous System

Mitochondrial dysfunction in LS predominantly affects the central nervous system (CNS), leading to hallmark neuropathological changes. Bilateral symmetrical lesions appear in the basal ganglia, thalamus, cerebellum, and brainstem. These lesions result from energy deficits and ROS-induced damage, leading to demyelination, gliosis, and neuronal loss.

The neurological symptoms of Leigh Syndrome include:

Developmental delay and regression

Hypotonia (low muscle tone)

Dystonia (involuntary muscle contractions)

Ataxia (lack of muscle coordination)

Ophthalmoplegia (paralysis of eye muscles)

Respiratory failure due to brainstem involvement

As the disease progresses, affected individuals experience worsening motor and cognitive impairments, ultimately leading to severe disability and premature death.

Systemic Effects Beyond the CNS

While Leigh Syndrome primarily affects the nervous system, mitochondrial dysfunction also impacts other organ systems. Metabolic abnormalities such as lactic acidosis arise due to impaired oxidative metabolism, leading to energy deficits in multiple tissues. Additionally, cardiac involvement, such as hypertrophic cardiomyopathy, has been observed in some cases, reflecting the high energy demands of the heart.

The gastrointestinal system may also be affected, with symptoms such as feeding difficulties, failure to thrive, and gastrointestinal dysmotility. This further complicates disease management and contributes to the overall severity of the condition.

Conclusion

Leigh Syndrome is a devastating disorder driven by mitochondrial dysfunction, resulting in widespread neurodegeneration and multi-organ involvement. The genetic heterogeneity and complexity of mitochondrial pathology make it a challenging condition to study and manage. Understanding the molecular basis of mitochondrial dysfunction in LS provides crucial insights into the disease mechanism and potential therapeutic avenues, though treatment remains limited. Continued research into mitochondrial bioenergetics and genetic contributions will be essential in advancing our knowledge of Leigh Syndrome and related mitochondrial disorders.

[drchristophedelongsblog]

The brain stem: A pillar of motor function

The brain stem is a vital structure of the central nervous system, located at the base of the brain and connecting it to the spinal cord. It plays an essential role in many bodily functions, including the coordination of movement.

Role of the brain stem in motor function

The brain stem contains motor nuclei, groups of neurons involved in the control of movement. These motor nuclei receive information from the brain, cerebellum and spinal cord, and transmit it to the muscles via the cranial nerves and descending spinal cord pathways.

More specifically, the brainstem is involved in:

- Control of voluntary movements ‍♀️: The motor nuclei of the brainstem, in collaboration with the motor cortex, cerebellum and basal ganglia, are involved in the planning, initiation and execution of voluntary movements.

- Control of reflex movements ️: The brainstem contains reflex centers that control automatic and involuntary movements, such as coughing, yawning, swallowing and the blink reflex.

- Maintaining balance and posture : The brainstem receives information from the balance organs (inner ear) and the body's sensory receptors, and uses it to adjust posture and maintain balance.

- Controlling eye, head and facial movements ️: The motor nuclei of the brainstem control the muscles that move the eyes, head and face.

Structure of the brain stem

The brainstem is made up of three main parts:

- The mesencephalon: This is the upper part of the brainstem, containing motor nuclei involved in controlling eye movements and visual and auditory reflexes.

- Bridge: This is the middle part of the brain stem, containing motor nuclei involved in controlling head and facial movements, as well as nerve fibers connecting the brain to the cerebellum.

- Medulla oblongata: This is the lower part of the brain stem, containing motor nuclei involved in controlling vital functions such as breathing, heart rate and blood pressure.

Brain stem injuries

Brain stem lesions can lead to a variety of motor disorders, such as :

- Hemiplegia

- Ataxia

- tremors

- Balance disorders

- Speech disorders

- Swallowing disorders

- Breathing disorders

Conclusion

The brainstem is an essential structure of the central nervous system, playing a crucial role in the coordination of movement, as well as in many other vital functions.

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[artrealla]

why'd you crack the door open man there was a sock on the door for a reason

[candythemew]

(Old Art) I REALLY wanna draw them again sometime soon my beloved IDIOT

(I love this concept art doodle sm.)

[mousebitecel]

having a normal one (thinking about how wilsons inevitable death is treated like the birth of a love story. thinking about how house refers to wilsons tumor like its their child. thinking about how they have a fight over their love for one another before resolving with an emotionally charged conversation on houses doorstep. thinking about how they abandon their individual futures, regardless of what those might hold, to have a future together, regardless of what that definitely holds)

[elodieunderglass]

i loathe repeating patterns with much of my heart. however i was very brave and finished this last week. does this perhaps get killie Another Egg?

(ignore the blacked out rectangles my Real Life Name art signature is there)

Ohhh I love this! You were VERY brave, look at all that fine line work. I love it when people on tumblr give compliments about lines. They say things like “I want to eat it” or “your lines are so crunchy and greebled” and so on.

For many years I did not know what to say about babies, when other people showed me their babies. Eventually I learned about the primary considerations of babies, and therefore, what to look for when observing and reporting on them. For example, if it’s very young and holds its head up well, commenting that the baby is clearly very advanced and clever is an excellent observation, when a basic reaction of “cute!” only convinces the most deluded or besotted parents. Human babies are mostly not cute, exactly, and if they aren’t deluded or besotted or sleep deprived, the parents can tell if you are lying or uninterested.

Anyway, what I’m trying to say here is that I love these lines a lot, even if I don’t understand why or how to compliment them. They remind me of illustrations that you would look at for a long time as a kid because they had unexpected detail in them. There is also something inexplicable in the slightly organic curve of the spiked collars and the observation of the jaw of the skull that feels familial to me. It’s very very similar genetically to how myself and my younger sibling think about those things and it reminds me of my sibling’s art.

Anyway, thank you so much. I find this compelling, as if you are a cousin, or as if I commissioned this in an alternate life. I would compliment this baby by saying it “looks like an old soul.”

[v0idwraith]

[me reading my psych 101 textbook] waow this is just like Disco Elysium…

[omegalomania]

first night of 2ourdust how are we feeling

[cutiesseasonisalmostover]

Aquamarine (2006) 🌺🪸💕

[helloarchivist]

Nothing intellectual to add to the space i just want to kiss Elias with tongue. All I've got atm but I'll keep yall apprised of any updates.

[corvidexoskeleton]

Lads i am afraid that depeche mode has a fucking chokehold on my brain for the foreseeable future. Completely unavoidable and no way to remedy it. Its been nice knowing you all.

[galactic-glamour-girl-posts]

I'm Mad, I'm Mad...

Actually I'm glad because a scan of the theatrical run of "I'm Mad" has been found!

The short itself isn't lost media, but its original theatrical version was for nearly 30 years. It is now on YouTube thanks to FT Depot.

UPDATE:

It got taken down by WarnerMedia, but it's on the Web Archive now.

[veatomis]

healing the world one yaoi lavellan x lavellan butt grab at a time 😌✊ with a special extra under the cut <3

(butt grabber Alas Lavellan belongs to @fenrisisms)