B-Box transcription factor BBX28 requires CONSTITUTIVE PHOTOMORPHOGENESIS1 to induce shade-avoidance response in Arabidopsis thaliana.

Shade avoidance syndrome is an important adaptive strategy. Under shade, major transcriptional rearrangements underlie the reallocation of resources to elongate vegetative structures and redefine the plant architecture to compete for photosynthesis. BBX28 is a B-box transcription factor involved in seedling de-etiolation and flowering in Arabidopsis (Arabidopsis thaliana), but its function in shade-avoidance response is completely unknown. Here, we studied the function of BBX28 using two mutant and two transgenic lines of Arabidopsis exposed to white light and simulated shade conditions. We found that BBX28 promotes hypocotyl growth under shade through the phytochrome system by perceiving the reduction of red photons but not the reduction of photosynthetically active radiation or blue photons. We demonstrated that hypocotyl growth under shade is sustained by the protein accumulation of BBX28 in the nuclei in a CONSTITUTIVE PHOTOMORPHOGENESIS1 (COP1)-dependent manner at the end of the photoperiod. BBX28 up-regulates the expression of transcription factor- and auxin-related genes, thereby promoting hypocotyl growth under prolonged shade. Overall, our results suggest the role of BBX28 in COP1 signaling to sustain the shade-avoidance response and extend the well-known participation of other members of BBX transcription factors for fine-tuning plant growth under shade.

Mortality Rate and Acute Kidney Injury Prevalence Reduction in COVID-19 Critical Patients Treated with Hemoperfusion.

Introduction: Coronavirus disease 2019 (COVID-19) induces organic damage mainly through the patient's immune overreaction. Hemoperfusion (HPF) can remove inflammatory cytokines and can reduce the negative effects of cytokine storm in COVID-19. We compared the mortality rate, inflammatory response, and acute kidney injury (AKI) prevalence among patients suffering from respiratory insufficiency secondary to COVID-19 treated with and without HPF with HA330 cartridge. Methods: Mortality rate, serum creatinine, and ferritin values were compared between patients suffering from respiratory insufficiency secondary to COVID-19 who received conventional treatment and another group of patients who additionally received four sessions of HPF with HA330. Results: Of 116 patients suffering from acute respiratory insufficiency secondary to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), one group (n: 84) received support treatment and the other group (n: 32) additionally received HPF with HA330 cartridge. Both groups had no renal disease and similar age and comorbidities at admission, except for obesity and mechanical ventilation requirement, which were significantly higher in the HPF group. Mortality rate (61% vs. 31%, P: 0.008), serum creatinine (1.4 vs. 0.5 mg/dl, P < 0.001), and post-HPF serum ferritin (2868 vs. 1675, P < 0.001) were significantly lower in the HPF group. Conclusion: Mortality rate, serum ferritin, and AKI were significantly reduced in critical COVID-19 patients who received HPF with HA330 cartridge than in those who did not receive it. These results were obtained despite the HPF group risk factors, such as obesity and mechanical ventilation, worsening its prognosis.