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Summary: Although DELLA protein destabilization mediated by post‐translational modifications is essential for gibberellin (GA) signal transduction and GA‐regulated anthocyanin biosynthesis, the related mechanisms remain largely unknown. In this study, we report the ubiquitination and phosphorylation of an apple DELLA protein MdRGL2a in response to GA signaling and its regulatory role in anthocyanin biosynthesis.MdRGL2a could interact with MdWRKY75 to enhance the MdWRKY75‐activated transcription of anthocyanin activator MdMYB1 and interfere with the interaction between anthocyanin repressor MdMYB308 and MdbHLH3 or MdbHLH33, thereby promoting anthocyanin accumulation.A protein kinase MdCIPK20 was found to phosphorylate and protect MdRGL2a from degradation, and it was essential for MdRGL2a‐promoting anthocyanin accumulation. However, MdRGL2a and MdCIPK20 were ubiquitinated and degraded by E3 ubiquitin ligases MdSINA1 and MdSINA2, respectively, both of which were activated in the presence of GA.Our results display the integration of SINA1/2 with CIPK20 to dynamically regulate GA signaling and will be helpful toward understanding the mechanism of GA signal transduction and GA‐inhibited anthocyanin biosynthesis. The discovery of extensive interactions between DELLA and SINA and CIPK proteins in apple will provide reference for the study of ubiquitination and phosphorylation of DELLA proteins in other species. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, a new LC-ESI-MS/MS-based method was validated for the quantitation of hemslecin A in rhesus monkey plasma using otophylloside A as internal standard (IS). Hemslecin A and the IS were extracted from rhesus monkey plasma using liquid-liquid extraction as the sample clean-up procedure, and were subjected to chromatography on a Phenomenex Luna CN column (150 × 2.0 mm, 3.0 µm) with the mobile phase consisting of methanol and 0.02 mol/mL ammonium acetate (55:45, v/v) at a flow rate of 0.2 mL/min. Detection was performed on an Agilent G6410B tandem mass spectrometer by positive ion electrospray ionization in multiple reaction monitoring mode, monitoring the transitions m/z 580.5 [M + NH4]+ → 503.4 and m/z 518.2 [M + NH4]+ → 345.0 for hemslecin A and IS, respectively. The assay was linear over the concentration range of 0.5-200 ng/mL and was successfully applied to a pharmacokinetic study in rhesus monkeys. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Ceftriaxone is known to cause biliary pseudolithiasis and, rarely, nephrolithiasis mainly in children. However, we reported the development of bilateral distal ureteral ceftriaxone-associated lithiasis in 7 adults, which suggests that the risk of ureterolithiasis impaction should be considered when treating patients with ceftriaxone, even in adults. To avoid strengthening greater renal damage, ureteroscopic insertion of double J stents may be an alternative management for patients with ureteral ceftriaxone-associated lithiasis. [ABSTRACT FROM AUTHOR]

In the current study, nano-hydroxyapatite/β-tricalcium phosphate (HA/β-TCP) ceramics scaffolds loaded with cationic liposomal ceftazidime (CLCs) prepared by modified reverse phase evaporation method, the investigations of their release characteristics were performed by the dissolution tests, in vitro anti-biofilm activity of the scaffolds was studied by the determination of bacterial susceptibility with ELISA. The mean particle size, zeta potential, pH and entrapment efficiency of the CLCs studied were 161.5 ± 5.37 nm, 60.60 ± 5.24 mV, 6.90 ± 0.07 and 16.57 ± 0.13%, respectively. Electron microscopic images of the samples indicated that the liposomes were well preserved in the scaffolds and that it was the CLCs rather than free ceftazidime releasing from the scaffolds. The minimal inhibitory concentrations (MICs) to Staphylococcus aureus of free ceftazidime and its liposomal formulation were 6.00 μg/mL and the release behaviors of both CLCs and free ceftazidime from scaffolds were based on the dissolution/diffusion processes, Fick's law. These results demonstrated that CLCs could inhibit remarkably the formation of S. aureus biofilm more effectively than free ceftazidime ( P < 0.05). The study demonstrated that the HA/β-TCP ceramic scaffolds was such a material that could sustain release CLCs and maintain the adequate amounts of CLCs to absorb to biofilm. It provided an ideal way to inhibit bacterial biofilms for clinical practices. [ABSTRACT FROM AUTHOR]

Aim/hypothesis. The objective of this study was to assess how long-term exposure to high glucose affects the α cell function and whether the increased glucagon secretion is mediated via insulin resistance. Materials and methods. We established a β cell-depleted rat model to obtain pure primary α cells. Furthermore, isolated rat islets and TC1-6 cells (a clonal α cell line) were exposed to high glucose (25 or 30 mmol/L) and low glucose (5.5 mmol/L) for up to 5 days to evaluate the influence of chronic glucose toxicity on glucagon secretion and glucagon gene expression. Moreover, we added insulin and/or Wortmannin to examine if the inhibitory effect of insulin on glucagon secretion was impaired by high glucose via the phosphatidylinositol 3 kinase/PKB protein kinase B pathway. Results. Both glucagon secretion and glucagon gene expression were increased in response to 5 days exposure to high glucose. While a moderate insulin concentration slightly inhibits glucagon secretion from rat islets and α TC1-6 cells at high glucose, a pronounced increase in glucagon secretion was observed at low glucose. We found that the insulin-mediated activity of the phosphatidylinositol 3 kinase/PKB protein kinase B pathway in the α cell was markedly impaired by chronic exposure to high glucose. Conclusion. The hypersecretion of glucagon induced by glucotoxicity may be secondary to insulin resistance of the α cell induced by impaired activity of the insulin signaling pathway. [ABSTRACT FROM AUTHOR]

The spatio-temporal expressed profiles of two kinds of chemical communication-related protein genes, the odorant-binding protein of Ac-ASP2 and chemosensory protein of Ac-ASP3, were identified by real-time polymerase chain reaction (PCR). Results obtained using the 2-ΔΔCt method showed that Ac-ASP2 was a gene coding antenna-specific protein that did not express in larvae and pupae, but had discontinuous high abundance periods at 1, 9, 15, 27 and 30 days. The expressing abundance at such periods was at least ten times higher than that at other periods. From the distribution of Ac-ASP3 mRNA observed in different tissues, the transcript levels seemed to be higher in the wings, abdomen and thorax (of order ∼106), and lower in the legs, antennae and head (of order ∼105). From highest to lowest, the original copy number was found in the various body parts in the following order: wings, abdomen, thorax, legs, antenna, and head. The results suggest that Ac-ASP3 has an intimate relation with the chemosensory behaviour of wings and abdomen in Apis cerana cerana. [ABSTRACT FROM AUTHOR]

NAC transcription factors play an important role in plant abiotic stress response. However, the molecular mechanism of how it regulates iron accumulation remain largely unknown in apple. Here, we show that MdNAC1 positively regulates iron accumulation under iron deficiency conditions. Overexpression of MdNAC1 show higher levels of iron accumulation and chlorophyll content as well as activated the activity of plasma membrane (PM) H+-ATPases in response to iron deficiency. Quantitative PCR (qPCR) analysis showed that the expression of several iron-related genes were significantly up-regulated in transgenic apple calli. Additionally, we identify an MdBT2 protein that interacts with the MdNAC1 protein. MdBT2 negatively regulates the protein stability of MdNAC1 by degrading it through the ubiquitinated 26S proteasome pathway. In addition, overexpression of MdBT2 in apple and Arabidopsis exhibited inhibition of iron accumulation and showed chlorosis in the new leaves. In sum, our study provided molecular and genetic evidence that the MdBT2 may negatively regulate iron response by mediating the MdNAC1 stability. • We identified an NAC transcription factor, MdNAC1, from apple and demonstrated that it was localized in the nucleus. • The over expression of MdNAC1 increased iron accumulation in transgenic apple calli and Arabidopsis. • MdBT2 interacts with MdNAC1and mediates the ubiquitination of MdNAC1. [ABSTRACT FROM AUTHOR]

C(sp3)-H Arylation, Secondary C-H Activation, 2-Alkylpyridine, Aryl Iodide, Palladium Corrigendum: Palladium-Catalyzed Secondary C(sp3)-H Arylation of 2-Alkylpyridines Keywords: C(sp3)-H Arylation; Secondary C-H Activation; 2-Alkylpyridine; Aryl Iodide; Palladium EN C(sp3)-H Arylation Secondary C-H Activation 2-Alkylpyridine Aryl Iodide Palladium 2909 2909 1 06/10/21 20210608 NES 210608 GRAPH. [Extracted from the article]

SUMMARY: Jasmonic acid (JA) induces chlorophyll degradation and leaf senescence. B‐box (BBX) proteins play important roles in the modulation of leaf senescence, but the molecular mechanism of BBX protein‐mediated leaf senescence remains to be further studied. Here, we identified the BBX protein MdBBX37 as a positive regulator of JA‐induced leaf senescence in Malus domestica (apple). Further studies showed that MdBBX37 interacted with the senescence regulatory protein MdbHLH93 to enhance its transcriptional activation on the senescence‐associated gene MdSAG18, thereby promoting leaf senescence. Moreover, the JA signaling repressor MdJAZ2 interacted with MdBBX37 and interfered with the interaction between MdBBX37 and MdbHLH93, thereby negatively mediating MdBBX37‐promoted leaf senescence. In addition, the E3 ubiquitin ligase MdSINA3 delayed MdBBX37‐promoted leaf senescence through targeting MdBBX37 for degradation. The MdJAZ2‐MdBBX37‐MdbHLH93‐MdSAG18 and MdSINA3‐MdBBX37 modules realized the precise modulation of JA on leaf senescence. In parallel, our data demonstrate that MdBBX37 was involved in abscisic acid (ABA)‐ and ethylene‐mediated leaf senescence through interacting with the ABA signaling regulatory protein MdABI5 and ethylene signaling regulatory protein MdEIL1, respectively. Taken together, our results not only reveal the role of MdBBX37 as an integration node in JA‐, ABA‐ and ethylene‐mediated leaf senescence, but also provide new insights into the post‐translational modification of BBX proteins. Significance Statement: BBX37 interacted with the senescence regulatory protein bHLH93 to enhance its transcriptional activation on the senescence‐associated gene SAG18, thereby promoting leaf senescence. JAZ2 interacted with BBX37 and interfered with the interaction between BBX37 and bHLH93, thereby negatively mediating BBX37‐promoted leaf senescence. SINA3 delayed the BBX37‐promoted leaf senescence through targeting BBX37 for ubiquitination and degradation. [ABSTRACT FROM AUTHOR]

• MdBT2 is a negative regulator in response to drought stress. • MdNAC143 is a positive regulator in response to drought stress. • MdBT2 interacts with MdNAC143 and promotes its degradation via the 26S proteasome pathway. • MdBT2 confers sensitivity to drought at least dependent on MdNAC143. Drought stress is a severe source of abiotic stress that can affect apple yield and quality, yet the underlying molecular mechanism of the drought stress response and the role of MdBT2 in the process remain unclear. Here, we find that MdBT2 negatively regulates the drought stress response. Both in vivo and in vitro assays indicated that MdBT2 interacted physically with and ubiquitinated MdNAC143, a member of the NAC TF family that is a positive regulator under drought stress. In addition, MdBT2 promotes the degradation of MdNAC143 via the 26S proteasome system. A series of transgenic assays in apple calli and Arabidopsis verify that MdBT2 confers susceptibility to drought stress at least in part by the regulation of MdNAC143. Overall, our findings provide new insight into the mechanism of MdBT2, which functions antagonistically to MdNAC143 in regulating drought stress by regulating the potential downstream target protein MdNAC143 for proteasomal degradation in apple. [ABSTRACT FROM AUTHOR]

• An extension Boekelheide-like rearrangement of 2-benzylpyridine N -oxides. • The reaction could give moderate to excellent yield with wide substrate scope. • Synthesis of phenyl-2-pyridylmethanol with high enantioselectivity. • Application for synthesis of related amide derivatives was reported. An effective method for the acylation of 2-benzylpyridine N -oxides and their fast in situ [3,3]-sigmatropic rearrangement was reported. This transformation has a wide substrate scope under mild conditions, giving moderate to excellent yields. The application for the synthesis of chiral phenyl-2-pyridylmethanol products was briefly explored. Furthermore, an interesting example of tandem substitution and in situ [3,3]-sigamatropic rearrangement of 2-benzylpyridine N -oxide with benzenecarboximidoyl chloride was reported. [ABSTRACT FROM AUTHOR]

As a representative bioactive component in Brazil green propolis, Artepillin C (ArtC; 3, 5-diprenyl-4-hydroxycinnamic acid) has been reported a wide variety of physiological activities including anti-tumor, anti-inflammatory, and antimicrobial activity etc. However, it seems incompatible that ArtC in vivo was characterized as low absorption efficiency and low bioavailability. In order to obtain the elucidation, we further investigated the physicochemical basis of ArtC interacting with human serum albumin (HSA) in vitro. We found a unique dynamic mode interaction between ArtC and HSA, which is completely different from other reported propolis bioactive components. Thermodynamic analysis showed that hydrophobic interactions and electrostatic forces are the main driving force. The competitive assay indicates that the binding site of ArtC with HSA is close to the Sudlow's site I. The findings of this study reveal the unique physicochemical transport mechanism of ArtC in the human body, which helps to further understand the uniqueness of the representative functional components of Brazilian green propolis in the human body. [ABSTRACT FROM AUTHOR]

Background: Pain, agitation-sedation and delirium management are crucial elements in the care of critically ill patients. In the present study, we aimed to present the current practice of pain, agitation-sedation and delirium assessments in Chinese intensive care units (ICUs) and investigate the gap between physicians' perception and actual clinical performance. Methods: We sent invitations to the 33 members of the Neuro-Critical Care Committee affiliated with the Chinese Association of Critical Care Physicians. Finally, 24 ICUs (14 general-, 5 neuroscience-, 3 surgical-, and 2 emergency-ICUs) from 20 hospitals participated in this one-day point prevalence study combined with an on-site questionnaire survey. We enrolled adult ICU admitted patients with a length of stay ≥24 h, who were divided into the brain-injured group or non-brain-injured group. The hospital records and nursing records during the 24-h period prior to enrollment were reviewed. Actual evaluations of pain, agitation-sedation and delirium were documented. We invited physicians on-duty during the 24 h prior to the patients' enrollment to complete a survey questionnaire, which contained attitude for importance of pain, agitation-sedation and delirium assessments. Results: We enrolled 387 patients including 261 (67.4%) brain-injured and 126 (32.6%) non-brain-injured patients. There were 19.9% (95% confidence interval [CI]: 15.9–23.9%) and 25.6% (95% CI: 21.2–29.9%) patients receiving the pain and agitation-sedation scale assessment, respectively. The rates of these two types of assessments were significantly lower in brain-injured patients than non-brain-injured patients (p = 0.003 and < 0.001). Delirium assessment was only performed in three patients (0.8, 95% CI: 0.1–1.7%). In questionnaires collected from 91 physicians, 70.3% (95% CI: 60.8–79.9%) and 82.4% (95% CI: 74.4–90.4%) reported routine use of pain and agitation-sedation scale assessments, respectively. More than half of the physicians (52.7, 95% CI: 42.3–63.2%) reported daily screening for delirium using an assessment scale. Conclusions: The actual prevalence of pain, agitation-sedation and delirium assessment, especially delirium screening, was suboptimal in Chinese ICUs. There is a gap between physicians' perceptions and actual clinical practice in pain, agitation-sedation and delirium assessments. Our results will prompt further quality improvement projects to optimize the practice of pain, agitation-sedation and delirium management in China. Trial registration: ClinicalTrials.gov, identifier NCT03975751. Retrospectively registered on 2 June 2019. [ABSTRACT FROM AUTHOR]

Summary The transcription factors p65 and IRF3 play key roles in the induction of cellular antiviral responses. Phosphorylation of p65 and IRF3 is required for their activity and constitutes a key checkpoint. Here we report that viral infection induced upregulation of INKIT, an inhibitor for NF-κB and IRF3 that restricted innate antiviral responses by blocking phosphorylation of p65 and IRF3. INKIT overexpression inhibited virus-induced phosphorylation of p65 and IRF3 and expression of downstream genes. In contrast, knockdown or knockout of INKIT had the opposite effect: Inkit −/− mice produced elevated levels of type I interferons and proinflammatory cytokines and were more resistant to lethal viral infection compared to wild-type. INKIT interacted with IKKα/β and TBK1/IKKɛ, impairing the recruitment and phosphorylation of p65 and IRF3. Viral infection induced IKK-mediated phosphorylation of INKIT at Ser58, resulting in its dissociation from the IKKs. Our findings thus uncover INKIT as a regulator of innate antiviral responses. [ABSTRACT FROM AUTHOR]

2-Methoxyestradiol has been synthesized from 17β-estradiol with 51% overall yield. • Four steps to the synthesis of 2-methoxyestradiol with 51% overall yield. • The key step is the ruthenium-catalyzed ortho-C(sp2)-H hydroxylation of phenol carbamate. • Our approach to access 2-methoxyestradiol is amenable to scale preparation. A four-step route for the synthesis of 2-methoxyestradiol (5) starting from 17β-estradiol (1) has been achieved with a 51% overall yield. The key step was the ruthenium-catalyzed ortho-C(sp2)-H bond hydroxylation of aryl carbamates. Using dimethyl carbamate as the directing group, [RuCl 2 (p-cymene)] 2 as the catalyst, PhI(OAc) 2 as the oxidant and trifluoroacetate/trifluoroacetic anhydride (1:1) as the co-solvent, the hydroxyl group could be singly installed at the 2-position of 3-dimethylcarbamoyloxyestradiol (2) with 65% yield. Subsequent methylation of hydroxy and removal of dimethyl carbamate afforded 2-methoxyestradiol (5). [ABSTRACT FROM AUTHOR]

Depending on the substrate used the CuBr2 or HBr systems in DMSO deliver slightly varying yields. [ABSTRACT FROM AUTHOR]

An improved para-selective C(sp2)-H borylation of anisole derivatives is described. The selective borylation is probably dominated by the change in electron density on the aromatic ring when a Lewis acid is coordinated with an anisole substrate. In addition, a sterically hindered bipyridyl ligand used in the reaction also favors para-selectivity. With this strategy, it has been demonstrated that the ratio of para-borylated products could be dramatically improved. The reaction proceeds at a milder temperature, and most substrates display moderate to good site-selectivity. [ABSTRACT FROM AUTHOR]

Two new compounds verboncin A (1) and verboncin B (4) and 14 known compounds (2–3 and 5–16) were isolated from Verbena bonariensis, and these 14 compounds were first obtained from this plant. Their chemical structures were established by one and two-dimensional NMR and HRESIMS analysis and the results were compared with literature values. The absolute configuration of 1 was determined by calculating electronic circular dichroism (ECD). The cytotoxicity of some of the compounds against MCF-7, HCT-116, MDA-MB-231, and SW620 human cancer cell lines were evaluated, in which compound 4 showed negligible cytotoxic activity with an IC50 value of 68.08 ± 0.35 µM against the MCF-7 cell line. [ABSTRACT FROM AUTHOR]

The AP2/ERF family is an important class of transcription factors involved in plant growth and various biological processes. One of the AP2/ERF transcription factors, RAP2.6L, participates in various stresses responses. However, the function of RAP2.6L is largely unknown in apples (Malus domestica). In this study, an apple gene homologous to Arabidopsis AtRAP2.6L, MdERF113, was analyzed by bioinformatic characterization, gene expression analysis and subcellular localization assessment. MdERF113 was highly expressed in the sarcocarp and was responsive to hormonal signals and abiotic stresses. MdERF113‐overexpression apple calli were less sensitive to low temperature, drought, salinity, and abscisic acid than wild‐type. Subcellular localization revealed that MdERF113 was a nuclear‐localized transcription factor, and yeast experiments confirmed that MdERF113 has no autonomous activation activity. Overall, this study indicated that MdERF113 plays a role in regulating plant growth under abiotic conditions. [ABSTRACT FROM AUTHOR]

Two new flavonoids, 8,2′-diprenyl-3,5,7,5′-tetrahydroxyflavone (1) and 8-(1-methoxy-2,3-dihydroxy-3-methylbutyl)naringenin (2), along with twelve known compounds (3–14), were isolated from the leaves of Macaranga pustulata. The structures of the new compounds 1 and 2 were established by detailed spectroscopic data analysis and ECD computational methods. The inhibitory effects of compounds 1–6 against NLRP3 inflammasome activation as well as the cytotoxic activities of compounds 1–4 against MCF-7 and HCT-116 cancer cell lines were investigated. Compound 3 showed weak cytotoxicity against HCT-116 (IC50 = 55.747 ± 3.212 μM). [ABSTRACT FROM AUTHOR]