Hybrid Nanoparticles of Manganese Oxide and Highly Reduced Graphene Oxide for Photodynamic Therapy.

BACKGROUND: Graphene-based nanomaterials possess unique optical, physicochemical and biomedical properties which make them potential tools for imaging and therapy. Manganese oxide nanoparticles are attractive candidates for contrast agents in magnetic resonance imagint (MRI). We used manganese oxide (Mn3O4) and highly reduced graphene oxide (HRG) to synthesize hybrid nanoparticles (HRG-Mn3O4) and tested their efficacy for photodynamic therapy (PDT) in breast cancer cells. METHODS: The newly synthesized nanoparticles were characterized by transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, UV-visible spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetry, and X-ray diffraction (XRD) analyses. We used standard protocols of cytotoxicity and PDT after exposing A549 cells to various concentrations of hybrid nanoparticles (HRG-Mn3O4). We also performed fluorescence microscopy for live/dead cellular analysis. A549 cells were incubated with nanoparticles for 24 h and stained with fluorescein diacetate (green emission for live cells) and propidium iodide (red emission for dead cells) to visualize live and dead cells, respectively. RESULTS: The cell viability analysis showed that more than 98% of A549 cells survived even after the exposure of a high concentration (100 µg/mL) of nanomaterials. These results confirmed that the HRG-Mn3O4 nanoparticles are nontoxic and biocompatible at physiological conditions. When the cell viability analysis was performed after laser irradiation, we observed significant and concentration-dependent cytotoxicity of HRG-Mn3O4 as compared to Mn3O4 nanoparticles. Fluorescence microscopy showed that almost 100% cells were viable when treated with phosphate buffered saline or Mn3O4 while only few dead cells were detected after exposure of HRG-Mn3O4 nanoparticles. However, laser irradiation resulted in massive cellular damage by HRG-Mn3O4 nanoparticles which was directly related to the generation of reactive oxygen species (ROS). CONCLUSIONS: HRG-Mn3O4 hybrid nanoparticles are stable, biocompatible, nontoxic, and possess therapeutic potential for photodynamic therapy of cancer. Further studies are warranted to explore the MRI imaging ability of these nanomaterials using animal models of cancer.

Intention and practice on personal preventive measures against COVID-19 among older adults in the Kingdom of Saudi Arabia: an epidemiological study using the Theory of Planned Behaviour.

Introduction: Older adults aged 65 years and above are among the most vulnerable to adverse outcomes and death following a COVID-19 infection. The weekly epidemiological updates by the World Health Organisation show that the continued emergence of concerning subtypes of the virus indicates that the pandemic remains a public health concern and the public should continue to comply with personal preventive measures (PPMs). This study applies the Theory of Planned Behaviour (TPB) which is rooted in the field of Public Health, Epidemiology, and Preventive Medicine to Saudi older adults to predict their health behaviour. Methods: This behavioural epidemiological study recruited older adult participants aged 65 years of age and above. A tool which consisted of sociodemographic and health-related questions, as well as questions regarding the components of the TPB, namely, Attitude, Subjective Norm, Perceived Behavioural Control was used. Bivariate analyses, followed by unadjusted and adjusted multivariable logistic regression analyses were performed to derive odds ratios and 95% confidence intervals. Results: The total number of participants was 502. The mean age was 70.34 years, with similar distributions between males and females. In total, 52.2% intended to practice PPMs, whereas only 48% had a good practice. Also, 56% had a favourable Attitude towards PPMs, 61.4% had a positive Subjective Norm and 39.8% had perceived they had a high control over their behaviour. Females, and high educational status were predictors for high intention to practice PPMs (OR = 1.59, 95% CI = 1.01-2.52 and OR = 2.72, 95% CI = 1.44-5.16 respectively). Further predictors included Attitudes, Subjective Norm and Perceived Behavioural Control. Results also show that intention to practice was significantly associated with a lower odd of practicing PPMs (OR = 0.06, 95% CI = 0.04-0.10). Conclusion: Current findings highlight the need to continue with public health efforts targeting vulnerable older adults. Also, the fact that intention negatively predicted practice highlights the need for further behavioural epidemiological studies addressing the intention-behaviour gap.

Intraoral Lipoma of the Cheek - A Case Report With a One-Year Follow-up and Review of Literature.

Lipomas are mesenchymal adipose tumors that are most common in the human body. However, they are rare in the oral cavity at an occurrence rate of 1% to 4% with male gender predilection. The case presented is of a 37-year-old male who presented with a large painless swelling on the right cheek region. The swelling was present for the past year and had aggravated in the previous one month, causing discomfort during mastication and speech. On clinical examination, a solitary non-fluctuating circumferential swelling on the right cheek was observed. A provisional diagnosis of lipoma was made based on the history and clinical examination, and it was decided to treat by surgical excision. A final diagnosis of lipoma was made based on histopathological analysis of the excised specimen. The patient at a one-week follow-up had recovered from his speech and chewing problems, and no recurrence was reported at a one-year follow-up.