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We report on charge transport across self-assembled monolayers (SAMs) of short tau peptides by probing the electron tunneling rates and quantum mechanical simulation. We measured the electron tunneling rates across SAMs of carboxyl-terminated linker molecules (C6H12O2S) and short cis-tau (CT) and trans-tau (TT) peptides, supported on template-stripped gold (AuTS) bottom electrode, with Eutectic Gallium-Indium (EGaIn)(EGaIn) top electrode. Measurements of the current density across thousands of AuTS/linker/tau//Ga2O3/EGaIn single-molecule junctions show that the tunneling current across CT peptide is one order of magnitude lower than that of TT peptide. Quantum mechanical simulation demonstrated a wider energy bandgap of the CT peptide, as compared to the TT peptide, which causes a reduction in its electron tunneling current. Our findings also revealed the critical role of phosphorylation in altering the charge transport characteristics of short peptides; more specifically, we found that the presence of phosphate groups can reduce the energy band gap in tau peptides and alter their electrical properties. Our results suggest that conformational and phosphorylation of short peptides (e.g., tau) can significantly change their charge transport characteristics and energy levels.

Cancer and chemotherapy-induced malnutrition increase death, reduce the response to treatment, and increase multiple kinds of side effects. The aim of this study was to investigate the effects of Mediterranean-neutropenic diet on the nutritional status of acute myeloid leukemia patients under chemotherapy. 50 patients were divided into two groups by a random allocation scheme: the Mediterranean-neutropenic diet (n = 25) and the neutropenic diet group (n = 25). The intervention was implemented during a one month period. The nutritional status was evaluated based on PG-SGA. Serum albumin levels and dietary intake were also measured. After the intervention, the mean serum albumin level in the intervention group was significantly higher than the beginning of the study (p = 0.09) and in comparison with the control group (p = 0.01). Also, the mean serum albumin level in the control group significantly decreased at the end of the study compared to the beginning of the study (p = 0.03). After intervention, the nutritional status of the patients in the intervention group was significantly improved compared to the control group. In general, based on the results of this study, the Mediterranean neutropenic diet improves nutritional status during chemotherapy by increasing food intake, preventing weight loss and increasing serum albumin levels

Aggregation of the natively unfolded protein α-synuclein (α-syn) is key to the development of Parkinson's disease (PD). Some nanoparticles (NPs) can inhibit this process and in turn be used for treatment of PD. Using simulation strategies, we show here that α-syn self-assembly is electrostatically driven. Dimerization by head-to-head monomer contact is triggered by dipole-dipole interactions and subsequently stabilized by van der Waals interactions and hydrogen bonds. Therefore, we hypothesized that charged nano-objects could interfere with this process and thus prevent α-syn fibrillation. In our simulations, positively and negatively charged graphene sheets or superparamagnetic iron oxide NPs first interacted with α-syn's N/C terminally charged residues and then with hydrophobic residues in the non-amyloid-β component (61-95) region. In the experimental setup, we demonstrated that the charged nano-objects have the capacity not only to strongly inhibit α-syn fibrillation (both nucleation and elongation) but also to disaggregate the mature fibrils. Through the α-syn fibrillation process, the charged nano-objects induced the formation of off-pathway oligomers.

Nanotechnology and nanomedicine are vitally promising scopes for cancer diagnosis and therapy. Likewise, molecular dynamics (MD) has become a novel major technique that developed to design pioneering nano-biosensor as well as nanocarriers in this regard. Furthermore, cancer diagnosis using nano-biosensors such as glioblastoma cancer in early stage is imperative to enhance the efficacy of treatment. Tumor cellderived exosomes or tumor antigens are nanovesicles responsible for tumorigenesis and transferring information between cells which delivery oncogenes and onco-microRNAs. They are also present in blood and other bodily fluids in the early stage of disease, and potentially can use in early detection of several cancer types. In this work, we report on the use of classical MD simulations to study the binding mechanism of functionalized single-walled carbon nanotubes (SWCNTs) with Tim-4 to the tumor-derived exosomes phosphatidylserine (Ptd-L-Ser) receptor. All-atom MD simulations of Tim-4-SWCNT and Tim-4- Ptd-L-Ser allowed us to observe several phenomena. These MD studies verify that Tim-4 retains its biological functionality when attached to SWCNT and provides a computational approach to confirming appropriate affinity between Tim-4 and Ptd-L-Ser receptor of tumor antigens.