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The linear approach to resource utilization has led to the accumulation of waste plastic in the environment for decades. Unfortunately, both traditional mechanical recycling and incineration have faced their bottlenecks that have always resulted in quality deterioration and value recovery failures. Recently, chemical recycling and upcycling processes, including the conversion of plastics into their virgin monomers, liquid fuels, or chemical feedstocks to produce value-added products, have been identified as the most promising strategy for recovering value from waste plastics. However, these methods are often cost prohibitive and relying on stringent conditions compared to current recycling methods. Accordingly, this Minireview summarizes recent trends and achievements in the chemical recycling and upcycling of waste plastics. We highlight three research topics: depolymerization of plastics into monomers; degradation of plastics into liquid fuels and waxes; and conversion of plastics into hydrogen, fine chemical feedstocks, and value-added functional materials. Indeed, chemical recycling and upcycling is a bright path to a circular and environmentally friendly plastic economy.

The coronavirus disease 2019 (COVID-19) triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) erupted in Hubei Province of China in December 2019 and has become a pandemic. Severe COVID-19 patients who suffer from acute respiratory distress syndrome (ARDS) and multi-organ dysfunction have high mortality. Several studies have shown that this is closely related to the cytokine release syndrome (CRS), often loosely referred to as cytokine storm. IL-6 is one of the key factors and its level is positively correlated with the severity of the disease. The molecular mechanisms for CRS in COVID-19 are related to the effects of the S-protein and N-protein of the virus and its ability to trigger NF-κB activation by disabling the inhibitory component IκB. This leads to activation of immune cells and the secretion of proinflammatory cytokines such as IL-6 and TNF-α. Other mechanisms related to IL-6 include its interaction with GM-CSF and interferon responses. The pivotal role of IL-6 makes it a target for therapeutic agents and studies on tocilizumab are already ongoing. Other possible targets of treating CRS in COVID-19 include IL-1β and TNF-α. Recently, reports of a CRS like illness called multisystem inflammatory syndrome in children (MIS-C) in children have surfaced, with a variable presentation which in some cases resembles Kawasaki disease. It is likely that the immunological derangement and cytokine release occurring in COVID-19 cases is variable, or on a spectrum, that can potentially be governed by genetic factors. Currently, there are no approved biological modulators for the treatment of COVID-19, but the urgency of the pandemic has led to numerous clinical trials worldwide. Ultimately, there is great promise that an anti-inflammatory modulator targeting a cytokine storm effect may prove to be very beneficial in reducing morbidity and mortality in COVID-19 patients.