Immune checkpoints are immune receptors that negatively regulate immune responses and T-cells through multiple mechanisms. Immune checkpoints are upregulated in various tumor cells and allow cancer cells to escape and evade specific antitumor immune surveillance. One of the most prominent of these checkpoints is PD-1/PD-L1 pathway. The binding of PD-L1 expressed by tumor cells to PD-1 on the surface of tumor-specific cytotoxic T lymphocytes (CTL) leads to CTL suppression. Moreover, PD-L1 can dramatically increase tumorigenesis and metastasis, so the measurement of expression levels of PD-1/PD-L1 is lucrative for predicting the cancer prognosis. Accordingly, one of the most novel and important techniques that emerged as a revolutionary therapy to achieve potential anti-tumor immune responses is blocking these immune checkpoints by specific monoclonal antibodies called immune checkpoint inhibitors (ICIs). Since 2014, seven anti-PD-1/PD-L1 monoclonal antibodies have been approved by the Food and Drug Administration (FDA) for therapy in an extensive spectrum of cancers. Immune checkpoint therapy has been demonstrated to be a promising strategy for controlling advanced various types of cancers. Hence, studying these new approaches to cancer therapy is recommended. The present review will briefly summarize the interaction between PD-1/PD-L1 pathway and tumor cells as well as the effect of PD-1/PD-L1 inhibitors in cancer.

The aim of the present study was to assess the hardness, corrosion, and cytotoxicity of a commercially available cobalt-chromium (Co-Cr) ALLOY before and after simulated heat treatments at porcelain ring temperature. Five Co-Cr samples were fabricated using a lost wax casting procedure. Heat treatments were carried out at 650 ° C, 750 ° C, 850 ° C, and 950 ° C. Vickers hardness was measured for as-cast and heat-treated samples. The corrosion test was carried out separately in 0. 1 N NaCl, 1% citric acid and articial saliva at room temperature using potentiodynamic polarization technique. Gingival tissue biopsy of patients was taken and cultured to measure the cell viability by MTT colorimetric assay. Lowest hardness was observed at 650 ° C. 0. 1 N NaCl and 1% citric acid corrosion medium showed a similar trend of corrosion rate. The least corrosion rate was found in articial saliva. Firing temperature has an impact on the physical, chemical, and biological properties of Co-Cr ALLOY in long-term clinical use.

Pd and Co nanoparticles were deposited on cellulose for use as a heterogeneous catalyst in the bimetallic catalytic reduction reaction. The catalyst was characterized with Energy Dispersive X-Ray Spectroscopy, X-Ray Diffraction pattern, Thermal Gravimetric Analysis, Flame Atomic Absorption Spectroscopy, and Transmission Electron Microscopy, and applied in the reduction reaction of nitroaromatics using NaBH4 at room temperature. Aromatic amines were obtained as the sole product of the reduction reaction during 2h. This reaction has some advantages such as mild reaction conditions, high yield, green solvent, and recyclable catalyst. Also, the recovered catalyst is applicable in the reduction reaction for 4 times without a significant decrease in the activity.

In this paper, the effect of Pd decorated Carbon nanotube system for Carbon monoxide gas sensor applications was studied. Various positions of Pd atom and CO molecule have been considered and investigated using ab initio atomic simulator software (Siesta and Quantumwise) to obtain the most appropriate structure for enhancing the sensitivity of Carbon nanotubes. According to the simulation results, the most stable configuration of Pd atom and CO molecule are obtained while Pd atoms stand parallel to the CNT with no carbon vacancy on and CO molecule approaches the Carbon nanotube with its Carbon atom. Results indicate that the obtained structure can be considered as an interesting candidate for gas sensing devices.

Co-Cr films were produced with electrodeposition with different pH at room temperature. The effect of electrolyte pH on the structural, surface morphology and magnetic properties of the films was studied. X-ray diffraction measurement showed that the films have hexagonal close packed structure. For the films deposited at different pH values, the surface morphologies with different-sized globular granules were observed whereas the morphology covered by uniformly distributed nanoscale grains was detected for the surfaces of all films produced from electrolytes with different Cr concentrations. Magnetic properties such as coercivity and saturation magnetization showed strong dependence on the electrolyte solution pH and consequently the crystallite size. The Co-Cr films with low Hc were achieved using relatively low electrolyte pH. The differences observed in the magnetic properties were attributed to the structural changes caused by the electrolyte pH. The Co-Cr films may have the potential applications in magnetic recording and sensors technologies.