Heating efficiency of multi-walled carbon nanotubes in the first and second biological windows

Quantum dot based-thermometry, in combination with double beam confocal microscopy and infrared thermal imaging, has been used to investigate the heating efficiency of multi-walled carbon nanotubes (MWCNTs) under optical excitation within the first (808 nm) and second (1090 nm) biological windows as well as in the spectral region separating them (980 nm). It has been found that for the three excitation wavelengths the heating efficiency of MWCNTs (10 nm in diameter and 1.5 μm in length) is close to 50%. Despite this “flat” heating efficiency, we have found that the excitation wavelength is, indeed, critical during in vivo experiments due to the spectral dependence of both tissue absorption and scattering coefficients. It has been concluded that efficiency and selectivity of in vivo photothermal treatments based on MWCNTs are simultaneously optimized when laser irradiation lies within the first or second biological window

Antioxidative stress actions of cocoa in colonic cancer: Revisited

Colorectal cancer is the third most common cancer in the world and is one of the major causes of cancer-related mortality in the world. Cancer is defined as a multistage process and divided into the following stages: initiation, promotion, and progression. In this disease, oxidative stress is involved in a large array of carcinogenic pathways associated with the proliferation of initiated cells and cellular malignancy. Therefore, the suppression of oxidative stress by natural antioxidant compounds has gained interest as an effective approach in colorectal cancer prevention. Accordingly, cocoa and its phenolic components have demonstrated to exert antioxidant activity and to be able to interfere with multiple carcinogenic signaling pathways. In this chapter, we reviewed the different in vitro and in vivo studies that have identified potential targets and mechanisms whereby cocoa and their flavonoid compounds could interfere with colonic cancer cells. In addition, recent evidence from human studies is also illustrated.This work was supported by the grants AGL2015-67087-R and RTI2018-095059-B-I00 (MINECO/FEDER, UE).Peer reviewe