MAGNETIC NANOPARTICLE-BASED APPROACHES IN CANCER THERAPY–A CRITICAL REVIEW

Cancer is definitely one of the leading causes of mortality worldwide. Failure in the efficacy of the standard treatments (chemo-, radiotherapy and surgery), and the severe side effects, resistance of tumor cells to chemotherapeutics have necessitated alternative therapeutic strategies. Magnetic nanoparticles (MNPs) have been assessed as potential cancer therapy materials. Their intrinsic magnetic properties provide a cancer detection, monitoring, and therapy platform based on multimodal theranostics. MNPs can be functionalized by binding them to a wide variety of substances, including chemotherapeutic drugs, radionuclides, nucleic acids, and antibodies. They can be used for drug delivery, magnetic or photothermal induced local hyperthermia and photodynamic therapy aimed at killing cancer cells at the tumor site. MNPs may also be useful to challenge drug resistance. The combination of different options of these treatment modalities offers a synergistic effect and significantly reduces the side effects. The functionalized MNPs may be used to remove the unwanted cells from blood, including leukemia cells and circulating tumor cells that key factors in the metastatic process. Despite numerous successful studies, there are still some unpredictable obstacles relevant to the use of MNPs in cancer therapy. This review mainly focuses on the application of MNPs in cancer treatment, covering future perspectives and challenges aspects

Interdigitated Flow Channel on a Proton Exchange Membrane Fuel Cell Investigated Using the Response Surface Methodology

Performance of the proton exchange membrane (PEM) fuel cell depends on the operating pressure, operating temperature, stoichiometric ratio of reactant gases, relative humidity, and rib width-to-channel width ratio (R:C), shape of the flow channel, and the number of passes on the flow channel. The effect of pressure, temperature, inlet reactant mass flow rate and rib width-to-channel width ratios of 1:1, 1:2, 2:1, and 2:2 on the power density of a PEM fuel cell with interdigitated flow channel of 25 cm^2 active area of was considered in this study. The response surface methodology was used for optimizing the four above mentioned parameters to find the optimum power density of the PEM fuel cell. The analysis of variance (ANOVA) was used to find the contribution of each parameter to the performance of the PEM fuel cell. Further, numerical results were compared with the experimental validation of the PEM fuel cell. Numerical results of power densities of interdigitated flow channel with R:C ratios of 1:1, 1:2, 2:1, and 2:2 were found to be 0.272, 0.292, 0.267, and 0.281 W/cm^2 and the corresponding experimental results of power density were 0.261, 0.266, 0.254, and 0.264 W/cm^2, respectively

Diethyl [(3-cyano-1-phenyl­sulfonyl-1H-indol-2-yl)meth­yl]phospho­nate

In the title compound, C20H21N2O5PS, the indole ring is essentially planar, with a maximum deviation of −0.0083 (18) Å. The methyl C atom of the methyl­phospho­nate group and the S atom lie 0.104 (2) and −0.2158 (6) Å, respectively, from the indole mean plane. The sulfonyl-bound phenyl ring is almost perpendicular to the indole ring system, with a dihedral angle of 82.30 (8)°. The ethyl side chains are disordered over two sets of sites, with occupancy factors of 0.737 (5)/0.263 (5) and 0.529 (11)/0.471 (11). In the crystal, mol­ecules are linked into centrosymmetric dimers via C—H⋯O hydrogen bonds, resulting in an R 2 2(18) graph-set motif. The crystal structure is further stabilized by C—H⋯π inter­actions

Novel substituted methylenedioxy lignan suppresses proliferation of cancer cells by inhibiting telomerase and activation of c-myc and caspases leading to apoptosis

Conventional solvent fractionation and bioactivity based target assays were used to identify a new anti-cancer molecule from Phyllanthus urinaria, a herbal medicinal plant used in South India. At each step of the purification process the different fractions that were isolated were tested for specific anti-proliferative activity by assays measuring the inhibition of [3H]thymidine incorporation, and trypan blue drug exclusion. The ethyl acetate fraction that contained the bioactivity was further purified and resolved by HPLC on a preparative column. The purity of each of the fractions and their bioactivity were checked. Fraction 3 demonstrated a single spot on TLC and showed maximum anti-proliferative activity. This fraction was further purified and the structure was defined as 7′-hydroxy-3′,4′,5,9,9′-pentamethoxy-3,4-methylene dioxy lignan using NMR and mass spectrometry analysis. The pure compound and the crude ethyl acetate fraction which showed anti-proliferative activities were examined for ability to target specific markers of apoptosis like bcl2, c-myc and caspases and for effects on telomerase. Four specific cancer cell lines HEp2, EL-1 monocytes, HeLa and MCP7 were used in this study. The results indicate that 7′-hydroxy-3′,4′,5,9,9′-pentamethoxy-3,4-methylene dioxy lignan was capable of inhibiting telomerase activity and also could inhibit bcl2 and activate caspase 3 and caspase 8 whose significance in the induction of apoptosis is well known. We believe that this compound could serve as a valuable chemotherapeutic drug after further evaluations

Preparation and selection of a eutectic phase change material for cooling the PV module under Thailand climatic conditions

Several studies have found that incorporating an appropriate melting temperature (Tmelt) of Phase Change Material (PCM) behind the PV module enhances the cooling effect. In this study, PCM is selected for hybrid cooling for summer and winter using six years of meteorological data obtained from NASA. Considering the hybrid cooling method, winter season Tamb is selected to optimize the Tmelt as the selected PCM must reach the latent heat property in an early sunshine. It is found that during winter, 70 % of the period, Tamb lies around 28 °C whereas the Tmelt of PCM should be in the range of 31-34 °C according to the modified optimization method. In total, twelve combinations of eutectic mixtures are prepared using Lauric Acid (LA), Myristic Acid (MA) and Stearic Acid (SA), and their thermophysical properties are analysed using a differential scanning calorimeter. Only seven eutectic mixtures attain the 31-34 °C Tmelt among that LA:MA (70:30) and LA:SA (70:30) show excellent latent heat of fusion of 194 J/g and 190 J/g, respectively. Furthermore, it is recommended that LA:MA (70:30) and LA:SA (70:30) are suitable for Thailand’s climatic conditions for PV module cooling

Comparative study for photovoltaic cooling using metal mesh inserted eutectic phase change material enclosure

Phase change material (PCM) is a predominant storage material that enables a higher cooling effect over sensible heat storage materials without the assistance of working fluid. In this study, novel PCM infused finned, and mesh finned containers are developed to help cooling photovoltaic (PV) in operation by reducing the PCM conduction resistance. The designed container is integrated underneath the back surface of the PV module and experimented under controlled weather conditions (indoor). Fins are attached behind the PCM container without any intermediate layer favors transferring the heat from the top to the bottom fin surface as a single unit. The main benefit of a PCM-infused fin container enhances the PCM liquid flow movement throughout the finned morphology and the heat dissipation rate increases between the finned PCM container and its surroundings. Moreover, incorporating metal mesh inside the PCM container resulting to the control of the conduction barrier and increased the heat transfer rate. It is found that metal mesh based finned PCM container shows an excellent performance enhancement between 85th and 150th minutes with a peak cooling of 2.20% and corresponding to the electrical power and energy productions of 2.01% and 2.71%, respectively compared to finned PCM container. The statistical approach on finned and mesh finned PCM containers shows that ambient temperature has a strong positive correlation with the temperature rise in photovoltaic resulting in performance degradation. Furthermore, it is recommended that the developed PCM containers are suitable for tropical climatic conditions to improve the PV power output