Local magnetic delivery of adeno-associated virus AAV2(quad Y-F)-mediated BDNF gene therapy restores hearing after noise injury

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Efficient polymer nanoparticle-mediated delivery of gene editing reagents into human hematopoietic stem and progenitor cells

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Nannochloropsis Extract–Mediated Synthesis of Biogenic Silver Nanoparticles,Characterization and In Vitro Assessment of Antimicrobial,Antioxidant and Cytotoxic Activities

Objective: To investigate the biogenic synthesis of silver nanoparticles (AgNPs) using partially purified ethylacetate extract of Nannochloropsis sp. hexane (EAENH) fraction of microalga. Methods: The green synthesis ofAgNPs was confirmed with UV-Vis spectrum which shows the surface plasmon resonance (SPR) at 421 nm. FourierTransform Infrared Spectra (FTIR) presented the involvement of functional groups like carboxyl groups of fatty acids,tetraterpenoids of xanthophylls, hydroxyl groups of polyphenols, carbonyl and amide linkage of proteins in the AgNPsynthesis. Gas Chromatography-Mass Spectrometry analysis (GCMS) revealed that phytochemicals like octadecanoicacid and hexadecanoic acid imply in capping, bioreduction, and stabilization of AgNps. Result: High-resolutionTransmission electron microscope (HRTEM), Dynamic light scattering (DLS), X-ray diffraction (XRD) and EDXanalysis showed the crystalline form of the AgNPs with Z-average size 57.25 nm. The zeta potential value of -25.7mV demonstrated the negative surface charge and colloidal stability of AgNPs. The antimicrobial activity of AgNPsdisplayed effective inhibition zone against selected bacterial and fungal pathogens. In vitro, antioxidant effects wereassessed by 1,1-diphenyl-2-picryl-hydrazyl (DPPH), hydrogen peroxide and reducing power assays which revealedexcellent scavenging potential for AgNPs than the extracts. The anti-proliferative potential of biofabricated AgNPsand extracts on Human Non-small lung cancer cell line (A549) was assessed using 3–(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay with IC50 values of 15 μgmL-1 and 175 μgmL-1 respectively. Conclusion:The study reveals that the microalgae-mediated AgNPs possesses potent antimicrobial and antioxidant activity alongwith the ability to stimulate apoptosis in A-549 cell line.     

Temperature-controlled power modulation compensates for heterogeneous nanoparticle distributions: a computational optimization analysis for magnetic hyperthermia

Purpose: To study, with computational models, the utility of power modulation to reduce tissue temperature heterogeneity for variable nanoparticle distributions in magnetic nanoparticle hyperthermia.

Methods: Tumour and surrounding tissue were modeled by elliptical two- and three-dimensional computational phantoms having six different nanoparticle distributions. Nanoparticles were modeled as point heat sources having amplitude-dependent loss power. The total number of nanoparticles was fixed, and their spatial distribution and heat output were varied. Heat transfer was computed by solving the Pennes’ bioheat equation using finite element methods (FEM) with temperature-dependent blood perfusion. Local temperature was regulated using a proportional-integral-derivative (PID) controller. Tissue temperature, thermal dose and tissue damage were calculated. The required minimum thermal dose delivered to the tumor was kept constant, and heating power was adjusted for comparison of both the heating methods.

Results: Modulated power heating produced lower and more homogeneous temperature distributions than did constant power heating for all studied nanoparticle distributions. For a concentrated nanoparticle distribution, located off-center within the tumor, the maximum temperatures inside the tumor were 16% lower for modulated power heating when compared to constant power heating. This resulted in less damage to surrounding normal tissue. Modulated power heating reached target thermal doses up to nine-fold more rapidly when compared to constant power heating.

Conclusions: Controlling the temperature at the tumor-healthy tissue boundary by modulating the heating power of magnetic nanoparticles demonstrably compensates for a variable nanoparticle distribution to deliver effective treatment.     

Concurrent removal of Cr(III), Cu(II), and Pb(II) ions from water by multifunctional TiO2/Alg/FeNPs beads

The use of multifunctional materials for water remediation is a modern approach where adsorption phenomena and heterogeneous photocatalysis can be applied for the removal of pollutants. Since the ideal remediation system should be able to remove both organic and inorganic pollutants, a crucial aspect to consider is the knowledge of operational parameters affecting the removal process, especially when heavy metal ions are present in concoction as in real systems. Given the proven efficiency of multifunctional TiO₂/Alg/FeNPs magnetic beads for the removal of model organic pollutants, this study investigated the possibility to exploit such system also for the removal of mixed heavy metals (MHM), specifically Cr(III), Cu(II), and Pb(II) ions, under ultraviolet irradiation at a wavelength of 254 nm. After a preliminary screening on the optimal catalyst loading, operating parameters such as the initial concentration of metal ions, contact and irradiation time, and pH were investigated to optimize the removal of metal ions using response surface methodology (RSM) via Box–Behnken design. Starting from a MHM solution containing 44 ppm of each metal ion, the removal of Pb(II), Cr(III), and Cu(II) ions in the aqueous solution was nearly completed (>98.4%) for all three ions within 72 min of irradiation at almost neutral pH (pH = 6.8). The stability of TiO₂/Alg/FeNPs was confirmed by retrieving and reusing the beads in three consecutive cycles of heavy metals removal without observing significant changes in catalyst efficiency.