RESUMO
OBJECTIVE: Alzheimer's disease, a progressive neurodegenerative disorder, severely impacts cognitive function and daily living. The current treatment provides only symptomatic relief, and thus, disease-modifying therapies targeting underlying causes are needed. Although several potential therapies are in various stages of clinical trials, bringing a new Alzheimer's drug to market remains challenging. Hence, researchers are also exploring monoclonal antibodies, tau protein inhibitors, and anti-inflammatory drugs as treatment options. Conventionally designed dosage forms come with limitations like poor absorption, first-pass metabolism, and low bioavailability. They also cause systemic adverse effects because these designed systems do not provide target- specific drug delivery. Thus, in this review, the authors highlighted the current advancements in the development of intranasal nanoformulations for the treatment of Alzheimer's disease. This strategy of delivering anti-Alzheimer drugs through the nasal route may help to target the drug exactly to the brain, achieve rapid onset of action, avoid first-pass metabolism, and reduce the side effects and dose required for administration. CONCLUSION: Delivering drugs to the brain through the nasal route for treating Alzheimer's disease is crucial due to the limited efficacy of existing treatments and the profound impact of the disease on patients and their families. Thus, by exploring innovative approaches such as nose-to-brain drug delivery, it is possible to improve the quality of life for individuals living with Alzheimer's and alleviate its societal burden.
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Contraction and flow of the actin cell cortex have emerged as a common principle by which cells reorganize their cytoplasm and take shape. However, how these cortical flows interact with adjacent cytoplasmic components, changing their form and localization, and how this affects cytoplasmic organization and cell shape remains unclear. Here we show that in ascidian oocytes, the cooperative activities of cortical actomyosin flows and deformation of the adjacent mitochondria-rich myoplasm drive oocyte cytoplasmic reorganization and shape changes following fertilization. We show that vegetal-directed cortical actomyosin flows, established upon oocyte fertilization, lead to both the accumulation of cortical actin at the vegetal pole of the zygote and compression and local buckling of the adjacent elastic solid-like myoplasm layer due to friction forces generated at their interface. Once cortical flows have ceased, the multiple myoplasm buckles resolve into one larger buckle, which again drives the formation of the contraction pole-a protuberance of the zygote's vegetal pole where maternal mRNAs accumulate. Thus, our findings reveal a mechanism where cortical actomyosin network flows determine cytoplasmic reorganization and cell shape by deforming adjacent cytoplasmic components through friction forces.
RESUMO
While the dynamics of dimers and polymer chains in a viscous solvent is well understood within the celebrated Rouse model, the effect of an external magnetic field on the dynamics of a charged chain is much less understood. Here, we generalize the Rouse model for a charged dimer to include the effect of an external magnetic field. Our analytically solvable model allows a fundamental insight into the magneto-generated dynamics of the dimer in the overdamped limit as induced by the Lorentz force. Surprisingly, for a dimer of oppositely charged particles, we find an enormous enhancement of the dynamics of the dimer center, which exhibits even a transient superballistic behavior. This is highly unusual in an overdamped system for there is neither inertia nor any internal or external driving. We attribute this to a significant translation and rotation coupling due to the Lorentz force. We also find that magnetic field reduces the mobility of a dimer along its orientation and its effective rotational diffusion coefficient. In principle, our predictions can be tested by experiments with colloidal particles and complex plasmas.
