Introduction on Coronavirus Disease (COVID-19) Pandemic: The Global Challenge.

By driving the ongoing pandemic of coronavirus disease 2019 (COVID-19), coronaviruses have become a significant change in twenty-first-century medicine, healthcare systems, education, and the global economy. This chapter rapidly reviews the origin, immunopathogenesis, epidemiology, diagnosis, clinical manifestations, and potential therapeutics of COVID-19. It would also explore the effects of the introduction of a single virus, the so-called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), on the public health preparedness planning.

Treatment of breast cancer in vivo by dual photodynamic and photothermal approaches with the aid of curcumin photosensitizer and magnetic nanoparticles.

Breast cancer is a neoplastic disease with a high mortality rate among women. Recently, photodynamic therapy (PDT) and photothermal therapy (PTT) attracted considerable attention because of their minimal invasiveness. The PTT approach works based on hyperthermia generation, and PDT approach employs laser irradiation to activate a reagent named photosensitizer. Therefore, in the current paper, a dual-functioned nanocomposite (NC) was designed for the treatment of breast cancer model in Balb/c mice with the combination of photodynamic and photothermal approaches. Transmission electron microscopy, UV-visible spectroscopy, FTIR, and XRD were employed to validate the nanostructure and silica coating and curcumin (CUR) immobilization on the Fe3O4 nanoparticles. The effect of Fe3O4/SiO2-CUR combined with PDT and PTT was assessed in vivo on the breast tumor mice model, and immunohistochemistry (IHC) was employed to evaluate the expression of apoptotic Bax and Caspase3 proteins. The TEM images, UV-visible absorption, and FTIR spectra demonstrated the successful immobilization of curcumin molecules on the surface of Fe3O4/SiO2. Also, MTT assay confirmed the nontoxic nature of Fe3O4/SiO2 nanoparticles in vitro. In the breast tumor mice model, we have assessed six treatment groups, including control, CUR + PDT, Blue + NIR (near-infrared) lasers, NC, NC + PTT, and NC + PDT + PTT. The tumor volume in the NC + PDT + PTT group showed a significant reduction compared to other groups (p < 0.05). More interestingly, the tumor volume of NC + PDT + PTT group showed a 27% decrease compared to its initial amount. It should be noted that no detectable weight loss or adverse effects on the vital organs was observed due to the treatments. Additionally, the IHC data represented that the expression of proapoptotic Bax and Caspase3 proteins were significantly higher in the NC + PDT + PTT group compared to the control group, indicative of apoptosis. To conclude, our data supported the fact that the NC + PDT + PTT strategy might hold a promising substitute for chemotherapy for the treatment of triple-negative breast cancers.