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Abstract Background Plastids originated from an ancient endosymbiotic event and evolved into the photosynthetic organelles in plant cells. They absorb light energy and carbon dioxide, converting them into chemical energy and oxygen, which are crucial for plant development and adaptation. However, little is known about the plastid genome to light adaptation. Petrocosmea, a member of the Gesneriaceae family, comprises approximately 70 species with diverse light environment, serve as an ideal subject for studying plastomes adapt to light. Results In this study, we selected ten representative species of Petrocosmea from diverse light environments, assembled their plastid genomes, and conducted a comparative genomic analysis. We found that the plastid genome of Petrocosmea is highly conserved in both structure and gene content. The phylogenetic relationships reconstructed based on the plastid genes were divided into five clades, which is consistent with the results of previous studies. The vast majority of plastid protein-coding genes were under purifying selection, with only the rps8 and rps16 genes identified under positive selection in different light environments. Notably, significant differences of evolutionary rate were observed in NADH dehydrogenase, ATPase ribosome, and RNA polymerase between Clade A and the other clades. Additionally, we identified ycf1 and several intergenic regions (trnH-psbA, trnK-rps16, rpoB-trnC, petA-psbJ, ccsA-trnL, rps16-trnQ, and trnS-trnG) as candidate barcodes for this emerging ornamental horticulture. Conclusion We newly assembled ten plastid genomes of Petrocosmea and identified several hypervariable regions, providing genetic resources and candidate markers for this promising emerging ornamental horticulture. Furthermore, our study suggested that rps8 and rps16 were under positive selection and that the evolutionary patterns of NADH dehydrogenase, ATPase ribosome, and RNA polymerase were related to the diversity light environment in Petrocosmea. This revealed an evolutionary scenario for light adaptation of the plastid genome in plants.

Abstract Background Licorice (Glycyrrhiza uralensis Fisch.), a well-known traditional medicine, is traditionally used for the treatment of respiratory disorders, such as cough, sore throat, asthma and bronchitis. We aim to investigate the effects of liquiritin (LQ), the main bioactive compound in licorice against acute lung injury (ALI) and explore the potential mechanism. Methods Lipopolysaccharide (LPS) was used to induce inflammation in RAW264.7 cells and zebrafish. Intratracheal instillation of 3 mg/kg of LPS was used for induction an ALI mice model. The concentrations of IL-6 and TNF-α were tested using the enzyme linked immunosorbent assay. Western blot analysis was used to detect the expression of JNK/Nur77/c-Jun related proteins. Protein levels in bronchoalveolar lavage fluid (BALF) was measured by BCA protein assay. The effect of JNK on Nur77 transcriptional activity was determined by luciferase reporter assay, while electrophoretic mobility shift assay was used to examine the c-Jun DNA binding activity. Results LQ has significant anti-inflammatory effects in zebrafish and RAW264.7 cells. LQ inhibited the expression levels of p-JNK (Thr183/Tyr185), p-Nur77 (Ser351) and p-c-Jun (Ser63), while elevated the Nur77 expression level. Inhibition of JNK by a specific inhibitor or small interfering RNA enhanced the regulatory effect of LQ on Nur77/c-Jun, while JNK agonist abrogated LQ-mediated effects. Moreover, Nur77-luciferase reporter activity was suppressed after JNK overexpression. The effects of LQ on the expression level of c-Jun and the binding activity of c-Jun with DNA were attenuated after Nur77 siRNA treatment. LQ significantly ameliorated LPS-induced ALI with the reduction of lung water content and BALF protein content, the downregulation of TNF-α and IL-6 levels in lung BALF and the suppression of JNK/Nur77/c-Jun signaling, which can be reversed by a specific JNK agonist. Conclusion Our results indicated that LQ exerts significant protective effects against LPS-induced inflammation both in vivo and in vitro via suppressing the activation of JNK, and consequently inhibiting the Nur77/c-Jun signaling pathway. Our study suggests that LQ may be a potential therapeutic candidate for ALI and inflammatory disorders.

Abstract Background The peri-operative effectiveness of ultrasound-guided great auricular nerve block (GANB) in patients, especially in adult patients undergoing middle ear microsurgery remains unclear. We hypothesized that ultrasound-guided GANB would decrease the hemodynamic responsiveness to incision and opioid consumption in middle ear microsurgery as well as the post-operative analgesia requirement. Methods Sixty patients undergoing middle ear microsurgery were randomized into two equal groups to receive either a GANB with 2 ml of 0.25% ropivacaine under ultrasound guidance (GANB group) or to receive a blank control intervention (without any performed injection) before general anesthesia inductions. The primary outcomes were hemodynamic changes of MAP (mean artery pressure) and HR (heart rate) to skin incision. The secondary endpoints were to determine the consumptions of propofol and remifentanil during the operation and the incidence of remedial analgesia 48 h post-operation to maintain VAS ≤ 3. Results The MAP post incision in GANB group was significantly lower than that in control group (GANB group 93.83 ± 11.72 mmHg vs. control group 100.87 ± 12.65 mmHg, P = 0.029). The increases for MAP and HR post incision were also lower in GANB group (∆MAP GANB group 11.90 ± 8.32 mmHg vs. control group 19.83 ± 10.37 mmHg, P = 0.002; ∆HR GANB group 3.67 ± 5.30 beat min− 1 vs. control group 8.23 ± 8.56 beat min− 1, P = 0.016). Remifentanil consumption was significantly decreased in GANB group (GANB group 401.55 ± 100.51 μg h− 1 vs. control group 697.34 ± 215.45 μg h− 1, P = 0.000). The incidence of remedial analgesia post-operation in GANB group (5/30) was significantly lower than that in control group (20/30, P = 0.000). Conclusion Ultrasound-guided GANB decreases the hemodynamic responsiveness to incision and remifentanil consumption in middle ear microsurgery as well as the post-operative analgesia requirement. Trial registration This trial was retrospectively registered at http://www.chictr.org.cn with the registration number of ChiCTR1800014333 on 6 January, 2018.