In vitro anti-prostate adenocarcinoma and lung cancer studies of phenoxyaniline-block-poly(methyl methacrylate) based nanocomposites via controlled radical polymerization

A phenoxyaniline-based macroinitiator is utilized for the first time in order to produce phenoxyaniline-block-poly(methyl methacrylate) composites through single electron transfer-living radical polymerization (SET-LRP) under mild conditions. A different weight percentage of Cloisite 93A is added into the polymer mixtures in order to increase their biochemical properties. The prepared block copolymer nanocomposites are characterized using ATR-IR, UV-vis-spectroscopy, XRD, Raman, TGA, DSC, a particle size analyzer, contact angle measurements and SEM in order to characterize their structural, thermal, surface and morphological properties. Further, the developed polymeric nanocomposites are successfully applied in two different cancer cell lines (prostate adenocarcinoma and lung cancer), which show excellent anticancer properties. Also, acridine orange/ethidium bromide (AO/EtBr) dual staining is performed, which causes drastic cell death by apoptosis in both A549 and PC-3 cell lines, which indicated that the prepared polymeric nanocomposites effectively inhibit the cell proliferation and induce the apoptosis in both the cancer cells. Here nanoclay is used for cancer treatment because of its complete water solubility, which essentially causes the formation of a cationic complex between the clay and drug through electrostatic interactions. Hence, the exchange of ions between the clay and other ions in the biological environment leads to inhibition of the proliferation of prostate adenocarcinoma and lung cancer cells in the system.

Towards More Efficient Data Valuation in Healthcare Federated Learning using Ensembling

Federated Learning (FL) wherein multiple institutions collaboratively train a machine learning model without sharing data is becoming popular. Participating institutions might not contribute equally - some contribute more data, some better quality data or some more diverse data. To fairly rank the contribution of different institutions, Shapley value (SV) has emerged as the method of choice. Exact SV computation is impossibly expensive, especially when there are hundreds of contributors. Existing SV computation techniques use approximations. However, in healthcare where the number of contributing institutions are likely not of a colossal scale, computing exact SVs is still exorbitantly expensive, but not impossible. For such settings, we propose an efficient SV computation technique called SaFE (Shapley Value for Federated Learning using Ensembling). We empirically show that SaFE computes values that are close to exact SVs, and that it performs better than current SV approximations. This is particularly relevant in medical imaging setting where widespread heterogeneity across institutions is rampant and fast accurate data valuation is required to determine the contribution of each participant in multi-institutional collaborative learning.

A new microscopic insight into membrane penetration and reorganization by PETIM dendrimers

Dendrimers are highly branched polymeric nanoparticles whose structure and topology, largely, have determined their efficacy in a wide range of studies performed so far. An area of immense interest is their potential as drug and gene delivery vectors. Realizing this potential, depending on the nature of cell surface-dendrimer interactions, here we report controlled model membrane penetration and reorganization, using a model supported lipid bilayer and poly(ether imine) (PETIM) dendrimers of two generations. By systematically varying the areal density of the lipid bilayers, we provide a microscopic insight, through a combination of high resolution scattering, atomic force microscopy and atomistic molecular dynamics simulations, into the mechanism of PETIM dendrimer membrane penetration, pore formation and membrane re-organization induced by such interactions. Our work represents the first systematic observation of a regular barrel-like membrane spanning pore formation by dendrimers, tunable through lipid bilayer packing, without membrane disruption.

Expression for aberration coefficients using nonlinear transforms--extension to spherocylindrical surfaces

Previously we have used a matrix method to do nonlinear calculations and presented exact expressions for the third and fifth order aberration coefficients for a general conic surface as functions of the latus rectum and eccentricity. In this paper we show how the method can be extended to include the case of a general spherocylindrical surface.