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Uncertainty in Multiclass Classification

Dr. Rishabh Pathak
1. What is Uncertainty in Classification? Uncertainty refers to the model’s confidence or doubt in its predictions. Quantifying uncertainty is important to understand how reliable each prediction is. In multiclass classification , uncertainty estimates provide probabilities over multiple classes, reflecting how sure the model is about each possible class. 2. Methods to Estimate Uncertainty in Multiclass Classification Most multiclass classifiers provide methods such as: predict_proba: Returns a probability distribution across all classes. decision_function: Returns scores or margins for each class (sometimes called raw or uncalibrated confidence scores). The probability distribution from predict_proba captures the uncertainty by assigning a probability to each class. 3. Shape and Interpretation of predict_proba in Multiclass Output shape: (n_samples, n_classes) Each row corresponds to the probabilities of ...
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Novel Functions for Cell Cycle Proteins in Post-Mitotic Neurons

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Dr. Rishabh Pathak

Cell cycle proteins, traditionally associated with regulating cell division and proliferation, have been increasingly recognized for their novel functions in post-mitotic neurons. Here are some key insights into the emerging roles of cell cycle proteins in non-dividing neurons:


1.      Regulation of Neuronal Plasticity:

o    Cyclins and Cyclin-Dependent Kinases (CDKs): Cyclins and CDKs, known for their roles in cell cycle progression, have been implicated in regulating neuronal plasticity and synaptic function in post-mitotic neurons. These proteins can modulate synaptic strength, dendritic spine morphology, and neurotransmitter release, influencing neuronal connectivity and information processing [T42].

o    Cell Cycle Checkpoint Proteins: Proteins involved in cell cycle checkpoints, such as p53 and retinoblastoma protein (Rb), have been shown to participate in neuronal plasticity processes, including dendritic arborization, axonal growth, and synapse formation. By integrating cellular stress signals, these proteins contribute to the adaptive responses of neurons to environmental cues [T43].

2.     Maintenance of Neuronal Homeostasis:

o    Cell Cycle Inhibitors: Cell cycle inhibitors, such as p21 and p27, play roles beyond cell cycle regulation in post-mitotic neurons. These proteins are involved in maintaining neuronal homeostasis by controlling processes like apoptosis, DNA repair, and oxidative stress response. Dysregulation of cell cycle inhibitors can lead to neuronal dysfunction and neurodegeneration [T44].

o  DNA Damage Response Proteins: Components of the DNA damage response pathway, activated during cell cycle checkpoints, have been identified as key players in neuronal survival and function. These proteins help protect neurons from genotoxic stress, maintain genomic integrity, and support neuronal longevity in the absence of cell division [T45].

3.     Implications for Neurological Disorders:

o    Neurodegenerative Diseases: Dysregulation of cell cycle proteins in post-mitotic neurons has been linked to various neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Aberrant cell cycle re-entry, impaired DNA repair mechanisms, and disrupted cell cycle protein expression contribute to neuronal degeneration and disease progression [T46].

o    Synaptopathies: Alterations in cell cycle protein function have also been associated with synaptopathies, disorders characterized by synaptic dysfunction and impaired neuronal communication. By influencing synaptic plasticity, neurotransmission, and synaptic maintenance, cell cycle proteins contribute to the pathophysiology of synaptopathic conditions such as autism spectrum disorders and schizophrenia [T47].

4.    Therapeutic Opportunities:

o    Targeting Cell Cycle Pathways: Modulating cell cycle pathways in post-mitotic neurons represents a potential therapeutic strategy for neuroprotection and neuroregeneration in various neurological disorders. By manipulating the activity of cell cycle proteins, it may be possible to enhance neuronal resilience, promote synaptic health, and mitigate disease-related neuronal damage [T48].

o    Precision Medicine Approaches: Precision medicine approaches that consider the specific roles of cell cycle proteins in individual neurological conditions could lead to tailored therapeutic interventions. By targeting the dysregulated cell cycle pathways unique to each disorder, personalized treatment strategies may offer improved outcomes for patients with neurodegenerative and synaptopathic disorders [T49].

In conclusion, the expanding understanding of cell cycle proteins in post-mitotic neurons highlights their diverse functions in regulating neuronal plasticity, maintaining homeostasis, and contributing to the pathogenesis of neurological disorders. Exploring the therapeutic potential of targeting cell cycle pathways in non-dividing neurons opens new avenues for developing innovative treatments aimed at preserving neuronal function, enhancing synaptic connectivity, and ultimately improving outcomes for individuals affected by neurological conditions.

 

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