Cold atmospheric plasma (CAP) is a near room-temperature ionized gas composed of highly reactive species. CAP also generates thermal radiation, ultraviolet radiation, and electromagnetic (EM) waves. So far, nearly all biological effects of CAP have relied on the chemical factors in CAP. Here, we first show that the EM emission from CAP can lead to the death of melanoma cells via a transbarrier contactless method. Compared with reactive species, the effect of the physical factors causes much stronger growth inhibition on a reactive species-resistant melanoma cell line B16F10. Such a physically triggered growth inhibition is due to a new cell death type, characterized by the rapid leakage of bulk solutions from the cells, resulting in cytoplasm shrinkage and bubbling on the cell membrane. The physically based CAP-triggered cell death can occur even there is a macroscale gap between the bulk CAP and cells, which includes an air gap (∼8 mm) and a dielectric material of the dish or plate (∼1 mm). Either a too large or a too small gap will inhibit such cell death. The physically triggered cellular pressure may cause the bubbling on cells, which can be inhibited in a hypotonic environment via the extracellular osmotic pressure. This study builds a foundation to use CAP as a physically based noninvasive cancer treatment.

Cold atmospheric plasma (CAP), a near room temperature ionized gas, has shown potential application in many branches of medicine, particularly in cancer treatment. In previous studies, the biological effect of CAP on cancer cells and other mammalian cells has been based solely on the chemical factors in CAP, particularly the reactive species. Therefore, plasma medicine has been regarded as a reactive species-based medicine, and the physical factors in CAP such as the thermal effect, ultraviolet irradiation, and electromagnetic effect have been regarded as ignorable factors. In this study, we investigated the effect of a physical CAP treatment on glioblastoma cells. For the first time, we demonstrated that the physical factors in CAP could reinstate the positive selectivity on CAP-treated astrocytes. The positive selectivity was a result of necrosis, a new cell death in glioblastoma cells characterized by the leak of bulk water from the cell membrane. The physically-based CAP treatment overcomed a large limitation of the traditional chemically based CAP treatment, which had complete dependence on the sensitivity of cells to reactive species. The physically-based CAP treatment is a potential non-invasive anti-tumor tool, which may have wide application for tumors located in deeper tissues.

Background: As the use of social media continues to rise, the presence of social media accounts among orthopaedic surgery residency programs can foster connections with other specialties, highlight departmental achievements, and be a resource for applicants to learn more about the program. This study evaluated the current utility and landscape of social media, with an emphasis on the use of Instagram, in orthopaedic surgery residency programs in the United States. Methods: A cross-sectional study of orthopaedic surgery residency Instagram accounts was performed. The Instagram accounts were evaluated for the number of followers, number of accounts following, and number of posts. Instagram posts were further categorized into academic, departmental, education, and COVID-19–related content. In addition, a search was performed to identify the presence of Twitter and Facebook accounts among orthopaedic surgery residency programs. Bivariate and multivariable logistic regression models were used to analyze the data in this study. Results: Of the 192 orthopaedic surgery residency programs evaluated, 108 programs (56%) had an Instagram account, 65 programs (34%) had a Twitter account, and 58 programs (30%) had a Facebook account. Of the 108 programs with an Instagram account, 92 accounts (85%) were created in 2020. A higher Doximity ranking of a program was positively associated with the presence of an Instagram account (p < 0.001). A significant correlation was found between the number of posts and the Instagram engagement score (p = 0.018). The majority of Instagram posts contained departmental content (54%) followed by social (13%) and COVID-19–related (10%) content. Conclusions: The presence of orthopaedic surgery residency programs on social media has grown significantly in the year 2020. With the presence of more than 50% of residency programs on Instagram, this can be a useful resource for prospective applicants and other healthcare professionals to gain insight into the activities of orthopaedic surgery residency programs across the United States.

Cold atmospheric plasma (CAP), an ionized gas with near room temperature, shows a wide application in medicine. CAP is a tunable source of complex chemical components including many reactive species,...

Cold atmospheric plasma (CAP) is a near-room-temperature, partially ionized gas composed of reactive neutral and charged species. CAP also generates physical factors, including ultraviolet (UV) radiation and thermal and electromagnetic (EM) effects. Studies over the past decade demonstrated that CAP could effectively induce death in a wide range of cell types, from mammalian to bacterial cells. Viruses can also be inactivated by a CAP treatment. The CAP-triggered cell-death types mainly include apoptosis, necrosis, and autophagy-associated cell death. Cell death and virus inactivation triggered by CAP are the foundation of the emerging medical applications of CAP, including cancer therapy, sterilization, and wound healing. Here, we systematically analyze the entire picture of multi-modal biological destruction by CAP treatment and their underlying mechanisms based on the latest discoveries particularly the physical effects on cancer cells.