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Caesalpinia sappan L. (C. sappan) has been used in Oriental medicine as an antitumor agent. The present study shows the effects of the chloroform extract of C. sappan on cell death in head and neck cancer cell lines. The viability of HNSCC4 and HNSCC31 cells (head and neck cancer cell lines) was noticeably decreased compared to that of HaCaT cells (control group) in the presence of chloroform extract. No significant difference was observed in the viability of HNSCC4 and HNSCC31 cells when compared with HaCaT cells in the presence of n-butanol, methanol, and water extracts. Exposure to the chloroform extract of C. sappan resulted in an increase in the Sub-G1 phase of the cell cycle and condensation and shrinkage of nuclei in the HNSCC4 and HNSCC31 cells. The levels of p53 and p21^WAF1/CIP1 were also increased in the HNSCC4 and HNSCC31 cells. The results suggest that the chloroform extract of C. sappan may increase cell death in the HNSCC4 and HNSCC31 cells, which is linked to increased cellular levels of p53 and p21^WAF1/CIP1.

Methamphetamine (METH) is an extremely addictive drug that has raised serious public health concerns recently. METH addiction not only results in neuronal cytotoxicity, but it also affects immune cell activity, including T lymphocytes. 6,4,7$\prime$-trihydroxyflavanone (THF), isolated from Dalbergia odorifera, has been studied for its antibacterial activity, but evidence for whether THF has an anti-cytotoxic and protective effect on T cell activation exposed to METH is lacking. In this study, results showed that treatment with THF was not cytotoxic to Jurkat T cells but dose-dependently mitigated the cytotoxicity induced by exposure to METH. The Western blot results demonstrating pre-treatment with THF maintained the expression of anti-apoptotic proteins and phosphorylation of PI3K/Akt/mTOR downregulated by treatment with METH. Furthermore, we found that decreased expression of IL-2 and CD69 by METH exposure was partially restored, and viability was significantly prevented by pre-treatment with THF in activated T cells. These findings were involved in re-elevated expression of anti-apoptotic proteins as well as recovered pathways including MAPK/PI3K/Akt/mTOR in activated T cells pre-exposed to METH. Our results suggest beneficial effects of THF against the cytotoxic and immune-modulating effect of METH on T cells and therapeutic potential of THF for patients with immunodeficiency caused by METH addiction.

Nowadays, because of great biomedical applications of state-of-the art prototyping (bio-printing), many studies have been conducted in this field with focus on three-dimensional prototyping. There are several mechanisms for bio-printing of live cells such as piezoelectric and thermal and pneumatic inkjeting systems. Cell viability should be preserved during the bio-printing process. Lots of researches have been carried out to investigate and compare cell viability through different prototyping mechanisms. In order to quantify percentage of the cells that are killed during the proto-typing process, applied stresses on the cell and consequently its deformation should be calculated. A maximum strain energy density that the cell can tolerate is reported in the range of 25 Kj ⋅ m^-3 to 100 Kj ⋅ m^-3. This can be considered as a criteria to find the percentage of the damaged cells during the bio-printing processes. In this study, the bio-printing of the cell has been modeled and the cell viability have been investigated. Firstly, it is shown that in modeling of the bio-printing process, the effects of dynamic flow on calculating the applied stress on the cell is not negligible and must be considered. In the next step, the percentage of damaged endothelial cell aggregate under 80 kPa applied pressure (64 MPa/m) and 200 micron nozzle diameter is reported. Based on findings of this study, the percentage of endothelial cells viability under mentioned condition is reported 76%. The proposed method of this study can be utilized to examine the cell viability and performance of each prototyping systems.

Recently, we introduced magnetophoretic circuits, composed of overlaid magnetic and metallic layers, as a novel single-cell analysis (SCA) tool. We showed the ability of these circuits in organizing large single-particle and particle-pair arrays. Assembling the cells in microarrays is performed with the ultimate goal of running temporal phenotypic analyses. However, for long-term studies, a suitable microenvironment for the cells to normally grow and differentiate is needed. Towards this goal, in this study, we run required biocompatibility tests, based on which we make the magnetophoretic-based microchip a suitable home for the cells to grow. The results confirm the ability of these chips in cell handling and show no unwanted cell behavior alteration due to the applied shear stress on them, the magnetic labeling, or the microenvironment. After this achievement, this tool would be ready for running important single-cell studies in oncology, virology, and medicine.

Tetra non-peripheral and peripheral substituted Zn(II) phthalocyanine (Pc) derivatives bearing 2,2-difluoro-2-[1,1,2,2-tetrafluoro-2-(trifluoromethoxy)ethoxy]ethoxy groups (KH-69, KH-71) were synthesized and characterized to be antioxidant and antimicrobial agents. Photo-physicochemical properties of these compounds were investigated. Then, the DPPH free radical scavenging activity of the Pc derivatives was found as 97.74% and 94.89%, respectively. Both the Pc complexes showed perfect DNA nuclease activity with double strain break against pBR 322 plasmid DNA at 100 mg/L concentration. KH-69 and KH-71 indicated good antimicrobial activity against studied Gram-positive and Gram-negative bacteria, and fungal strains. Moreover, the Pcs showed excellent cell viability inhibition activity even at the lowest concentration. These Pc derivatives inhibited P. aeroginasa and S. aureus biofilm formation. The Pcs showed the highest biofilm inhibition with photodynamic therapy against S. aureus and P. aeroginasa with 95.40% and 90.03%, respectively.

PEG-encapsulated colloidal nanocrystal clusters (CNCs) have been synthesized via a one-step solvothermal process at a temperature of 230°C. The composition, phase, and morphology of these CNCs have been characterized by X-ray diffraction and transmission electron microscopy. Studies show that each particle is a cluster structure consisting of small primary iron oxide nanocrystals. Magnetic measurements reveal the superparamagnetic nature of these CNCs at room temperature. The CNCs with different sizes (80 nm or 95 nm) can be obtained by changing the time of reaction. The dispersibility and colloidal stability of these CNCs with PEG as the major surface group have also been discussed. In vitro cytotoxicity of these CNCs with different thickness PEG layer on HeLa cell has also been assayed. Cytotoxicity results reveal that the CNCs concentration and the incubation time can influence the cell viability, and the size of CNCs almost does not affect the cell viability.