Green synthesis, formulation and biological evaluation of a novel ZnO nanocarrier loaded with paclitaxel as drug delivery system on MCF-7 cell line.

In this study we design green synthesis of a novel ZnO nanocarrier loaded with paclitaxel as a drug delivery system with high cytotoxicity against breast cancer cell line (MCF-7) and low side effects on the normal cell line (fibroblast). Paclitaxel is formulated in high concentration in Cremophor EL because of its low solubility. Zinc oxide nanoparticles (ZnO NPs) were prepared by the ethanolic extract of Camellia sinensis L., then coated with chitosan (Ch) and loaded with paclitaxel (PTX) to improve drug delivery. The physicochemical properties were observed by transmission electron microscopy (TEM), thermo-gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), and Fourier transform infrared spectroscopy (FTIR). Drug loading on ZnO-Ch NPs was measured by high performance liquid chromatography (HPLC). In vitro apoptosis assay was assessed by flow cytometry. The cytotoxic effect of the nanocarrier drug was investigated using MTT assay in cancerous and normal cell lines. The PTX-loaded ZnO-Ch NPs showed cytotoxic effects on MCF-7 cells, with minimal detrimental effects on normal fibroblasts. The results of apoptosis assay were compliant with MTT findings. Generally, ZnO-Ch NPs could be used as a promising drug delivery platform for PTX with low side effect on normal cell line and high cytotoxic effect on breast cancer cell line.

The relation between structural, rugometric and fractal characteristics of hard dental tissues at micro and nano levels.

Human tooth exhibits a structure of a mixture of inorganic hydroxyapatite nanocrystals and organic phases. The aim of this study is to investigate different tissues of human canine teeth surface along with the micro structure parameters of each tissue. X-ray diffraction (XRD) is used to study the amorphous or crystalline nature of each tissue with different mineral compositions and crystalline structures where the highest crystalline quality is related to enamel. The surfaces are also examined by energy-dispersive X-ray spectrometry. Moreover, crystalline quality factor is carried out to estimate the crystallinity of the tissues. Also, based on the basic Scherrer equation, the Williamson-Hall equation is applied to extend the formula for the XRD. Enamel and cementum tissues of a typical human tooth, which look similar, are composed of a large variety of wide lines with different widths through Raman spectra analysis. In addition, the applied scanning electron microscopy extracts similar morphology for all tissues with round granular structures which are denser in the cementum. Atomic force microscopy is finally used for investigation of micro-morphologies of the different tissues and the results are compared with the fractal analysis which ends to the bifractal and anisotropic nature of enamel and cementum along with monofractal and isotropic nature of dentin.

Hybrid control combined with a voluntary biosignal to control a prosthetic hand.

In this research, the combination of fuzzy/PD and EMG signals, as direct command control, is proposed. Although fuzzy/PD strategy was used to control force position of the artificial hand, the combination of that with EMG signaling to voluntary direct command control is a novel method. In this paper, the EMG signal and its role in effective communication between a DC motor with a voltage trigger and neurofeedback are initially explained. Moreover, by introducing a filtration method, EMG pulses are obtained as stepping pulses with a signal-specific height of a voltage between 0 and 6 V, according to EMG domain voltage, with a time interval adapted from the EMG stimulus pulses. Two data points from each channel of EMG were extracted. The domain of the voltage of the EMG signal is impacted on the output of the fuzzy logic unit, and also the time amount between each stimulus of the EMG signal is the input of the PD controller. By this method, a user can influence grip position and grasping force of his/her prosthesis.