Dose‐dependent study of effects of 532‐nm continuous wave laser on rat skin: A mechanistic insight

Abstract

Visible lasers emitting in the green spectral region are being routinely employed in various medical and defense fields namely treatment of pigmented lesions, tattoo inks, port wine stains, dazzling the target or mob dispersal. Despite their increasing applications, lasers also tend to pose occupational hazards to operators, ancillary personnel, individuals undergoing laser therapies. This study was aimed at investigating the effects of different doses of 532‐nm continuous wave laser on rat skin. The present study demonstrated that higher fluences of 532‐nm continuous wave (CW) laser induces significant tissue damage through induction of tumor necrosis factor‐α, cyclooxygenase‐2, tumor protein (p53), PARP 1, caspase3 which in turn leads to tissue damage and cell death. Furthermore, level of heat shock proteins, pAkt were found up‐regulated as a cope up response to laser‐induced stress. On the basis of the findings, irradiation with 532‐nm CW laser up to 2.5 J/cm2 was found within the safe exposure limits. Thus, it is probably the first attempt to demonstrate the tissue damage induced by 532‐nm CW laser on skin, which may help in choosing safe laser dose for certain skin‐based applications and evolving methods to ameliorate laser‐inflicted injuries.

Imaging vs Nonimaging Raman Spectroscopy for High-Throughput Single-Cell Phenotyping

“…However, stronger excitation can produce visible cell damage if done carelessly. This can manifest immediately, e.g., as ablation , or bubbles, or in less immediate ways, such as changes in cell signaling, − proliferation, , or cell blebbing . The protocol for measuring Raman-based single-cell profiles should therefore be determined by the biological hypothesis being tested by the experiment, the resilience of the cell types, and the consideration of what (if any) changes in the sample are acceptable.…”