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A highly chemoselective cascade Wolff rearrangement/acylation reaction between 5-aminopyrazoles and diazo compounds has been developed. The protocol can facilitate the switchable synthesis of 4-hydroxy-pyrazolo[3,4-b]pyridin-6-ones and N-pyrazole amides with the merits of a broad substrate scope, high functional group compatibility, and green and sustainable performance manner. All reactions proceeded efficiently without any catalyst and additives (acid and base) and resulted in the release of benign N2, wherein diethyl carbonate served as a green benign solvent.

Background Tiller number is a factor determining panicle number and grain yield in wheat (Triticum aestivum). Auxin plays an important role in the regulation of branch production. PIN-FORMED 1 (PIN1), an auxin efflux carrier, plays a role in the regulation of tiller number in rice (Oryza sativa); however, little is known on the roles of PIN1 in wheat. Results Nine homologs of TaPIN1 genes were identified in wheat, of which TaPIN1-6 genes showed higher expression in the stem apex and young leaf in wheat, and the TaPIN1-6a protein was localized in the plasma membrane. The down-expression of TaPIN1s increased the tiller number in TaPIN1-RNA interference (TaPIN1-RNAi) transgenic wheat plants, indicating that auxin might mediate the axillary bud production. By contrast, the spikelet number, grain number per panicle, and the 1000-grain weight were decreased in the TaPIN1-RNAi transgenic wheat plants compared with those in the wild type. In summary, a reduction of TaPIN1s expression increased the tiller number and grain yield per plant of wheat. Conclusions Phylogenetic analysis and protein structure of nine TaPIN1 proteins were analyzed, and subcellular localization of TaPIN1-6a was located in the plasma membrane. Knock-down expression of TaPIN1 genes increased the tiller number of transgenic wheat lines. Our study suggests that TaPIN1s is required for the regulation of grain yield in wheat.

In-source fragmentation-based high-resolution mass spectrometry (ISF-HRMS) is a potential analytical technique, which is usually used to profile some specific compounds that can generate diagnostic neutral loss (NL) or fragment ion (FI) in ion source inherently. However, the ISF-HRMS method does not work for those compounds that cannot inherently produce diagnostic NL or FI in ion source. In this study, a derivatization-based in-source fragmentation-information-dependent acquisition (DISF-IDA) strategy was proposed for profiling the metabolites with easily labeled functional groups (submetabolomes) by liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry (LC-ESI-Q-TOF MS). As a proof-of-concept study, 36 carboxylated compounds labeled with N,N-dimethylethylenediamine (DMED) were selected as model compounds to examine performance of DISF-IDA strategy in screening the carboxylated metabolites and acquiring their MSn spectra. In ESI source, the DEMD-derived carboxylated compounds were fragmented to produce characteristic neutral losses of 45.0578, 63.0684, and/or 88.1000 Da that were further used as diagnostic features for screening the carboxylated metabolites by DISF-IDA-based LC-Q-TOF MS. Furthermore, high-resolution MSn spectra of the model compounds were also obtained within a single run of DISF-IDA-based LC-Q-TOF MS analysis, which contributed to the improvement of the annotation confidence. To further verify its applicability, DISF-IDA strategy was used for profiling carboxylated submetabolome in mice feces. Using this strategy, a total of 351 carboxylated metabolites were detected from mice feces, of which 178 metabolites (51% of the total) were positively or putatively identified. Moreover, DISF-IDA strategy was also demonstrated to be applicable for profiling other submetabolomes with easily labeled functional groups such as amino, carbonyl, and cis-diol groups. Overall, our proposed DISF-IDA strategy is a promising technique for high-coverage profiling of submetabolomes with easily labeled functional groups in biological samples.

Summary Due to the low cost and high energy density, the room temperature (RT) Na/S battery system is deemed as one of the best potential energy-storage systems. However, various issues still severely hinder its practical applications, especially the shuttle effect caused by soluble sodium polysulfides (NaPSs) and the low conversion efficiency of S8 and Na2S2/Na2S in S cathodes. Recently, various strategies were adopted into RT-Na/S batteries to boost the electrochemical kinetics of S cathodes, which are capable of significantly accelerating (or altering) the redox process and mitigating the shuttle effect of S cathodes. Herein, the representative works have been systematically reviewed, with emphasis on the roles of carbon-based hosts, covalent S composites, catalytic metal-modified hosts, and other functional components. Furthermore, the future challenges and research directions for the S cathodes have also been prospected in detail to provide guideline for the development of RT-Na/S batteries.

The expansion of a hexanucleotide repeat GGGGCC (G4C2) in the C9orf72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The G4C2 expansion leads to repeat-associated non-AUG (RAN) translation and the production of toxic dipeptide repeat (DPR) proteins, but the mechanisms of RAN translation remain enigmatic. Here, we report that the RNA helicase DHX36 is a robust positive regulator of C9orf72 RAN translation. DHX36 has a high affinity for the G4C2 repeat RNA, preferentially binds to the repeat RNA’s G-quadruplex conformation, and efficiently unwinds the G4C2 G-quadruplex structures. Native DHX36 interacts with the G4C2 repeat RNA and is essential for effective RAN translation in the cell. In induced pluripotent stem cells and differentiated motor neurons derived from C9orf72-linked ALS patients, reducing DHX36 significantly decreased the levels of endogenous DPR proteins. DHX36 is also aberrantly upregulated in tissues of C9orf72-linked ALS patients. These results indicate that DHX36 facilitates C9orf72 RAN translation by resolving repeat RNA G-quadruplex structures and may be a potential target for therapeutic intervention.

A strategy to obtain chiral silica using an achiral stereoregular polymer with polyhedral oligomeric silsesquioxane (POSS) side chains is described herein. The preferred helical conformation of the POSS-containing polymer could be achieved by mixing isotactic polymethacrylate-functionalized POSS (it-PMAPOSS) and a chiral dopant. The array structure of POSS molecules, which are placed along the helical conformation, is memorized even after removing the chiral dopant at high temperatures, leading to a chiral silica compound with exclusive optical activity after calcination.

We analyzed the effects of ginsenoside Rb1 on hyperlipidemic in model mice. Using stool, plasma and hepatic tissue samples, we observed that the genera Blautia and Allobaculum were increased and Turicibacter was decrease in Rb1-treated mice as compared to untreated model mice. Ether lipid metabolism, glycerolipid metabolism, and glyoxylate and dicarboxylate metabolism were differentially enriched between the Rb1 and model groups. Lipidomics revealed 169 metabolites differentially expressed between the model and Rb1 groups in a positive ion model and 58 in a negative ion model. These metabolites mainly participate in glycerophospholipid, linoleic acid, and alpha-linolenic acid metabolism. The main metabolites enriched in these three pathways were phosphatidylcholine, diacylglycerol and ceramide, respectively. In a transcriptome analysis, 766 transcripts were differentially expressed between the Rb1 and model groups. KEGG analysis revealed lysine degradation, inositol phosphate metabolism, and glycerophospholipid metabolism to be the main enriched pathways. Multiomics analysis revealed glycerophospholipid metabolism to be a common pathway and phosphatidylcholine the main metabolite differentially enriched between the Rb1 and model groups. Results from fecal transplanted germ-free mice suggest that to suppress hyperlipidemia, Rb1 regulates gut microbiota by regulating the synthesis and decomposition of phosphatidylcholine in glycerophospholipid metabolism, which in turn decreases serum total cholesterol.

Tea leaves possess numerous volatile organic compounds (VOC) that contribute to tea’s characteristic aroma. Some components of tea VOC were known to exhibit antimicrobial activity; however, their impact on bacteria remains elusive. Here, we showed that the VOC of fresh aqueous tea leaf extract, recovered through hydrodistillation, promoted cell division and tryptophan-dependent indole-3-acetic acid (IAA) production in Pseudomonas sp. NEEL19, a solvent-tolerant isolate of the tea phylloplane. 1-octanol was identified as one of the responsible volatiles stimulating cell division, metabolic change, swimming motility, putative pili/nanowire formation and IAA production, through gas chromatography-mass spectrometry, microscopy and partition petri dish culture analyses. The bacterial metabolic responses including IAA production increased under 1-octanol vapor in a dose-dependent manner, whereas direct-contact in liquid culture failed to elicit such response. Thus, volatile 1-octanol emitting from tea leaves is a potential modulator of cell division, colonization and phytohormone production in NEEL19, possibly influencing the tea aroma.

To explore the effect of herb-partitioned moxibustion (HPM) on tight junctions (TJs) of intestinal epithelial cells in Crohn disease (CD) mediated by tumor necrosis factor-α (TNF-α)-nuclear factor kappa B (NF-κB)-myosin-light-chain kinase (MLCK) pathway. Forty-eight male Sprague-Dawley rats were randomly divided into a normal control (NC) group, a model control (MC) group, an HPM group and a mesalazine (MESA) group, with 12 rats in each group. Trinitrobenzene sulfonic acid (TNBS) was administered to establish CD models. When the model was confirmed a success, the HPM group rats were treated with HPM at Tianshu (ST 25) and Qihai (CV 6), while the MESA group rats were given MESA solution by lavage. When the intervention finished, the colonic epithelial tissues were separated, purified and cultured in each group to establish the intestinal epithelial barrier model in vitro, and TNF-α was added (100 ng/mL) in the culture medium and maintained for 24 h to establish an increased epithelial permeability model. Transepithelial electrical resistance (TEER) was used to examine the permeability of the barrier; Western blot was used to observe the expressions of the proteins related to TJs of intestinal epithelial cells mediated by TNF-α-NF-κB-MLCK pathway; immunofluorescence staining was used to observe the expressions and distributions of tight junction proteins in the intestinal epithelium. After TNF-α induction, compared with the MC+TNF-α group, the TEER value increased significantly in the HPM+TNF-α and MESA+TNF-α groups (both P

Novel quinazolinone compounds have been studied in the field of drug discovery for a long time. Among their broad range of pharmacological effects, certain compounds effectively inhibit cancer cell proliferation. MJ-33 is a quinazolinone derivative with proposed anticancer activities that was synthesized in our laboratory. The present study aimed to evaluate the anticancer activity of MJ-33 in fluorouracil (5FU)-resistant colorectal cancer cells (HT-29/5FUR) and to investigate the underlying molecular mechanisms. The cell viability assay results indicated that HT-29/5FUR cell viability was inhibited by MJ-33 treatment in a concentration-dependent manner compared with the control group. The cellular morphological alterations observed following MJ-33 treatment indicated the occurrence of apoptosis and autophagy, as well as inhibition of cell proliferation in a time-dependent manner compared with the control group. The acridine orange, LysoTracker Red and LC3-green fluorescent protein staining results indicated that MJ-33 treatment significantly induced autophagy compared with the control group. The DAPI/TUNEL dual staining results demonstrated increased nuclear fragmentation and condensation following MJ-33 treatment compared with the control group. The Annexin V apoptosis assay and image cytometry analysis results demonstrated a significant increase in apoptotic cells following MJ-33 treatment compared with the control group. The western blotting results demonstrated markedly decreased Bcl-2, phosphorylated (p)-BAD, pro-caspase-9 and pro-caspase-3 expression levels, and notably increased cytochrome c and apoptotic peptidase activating factor 1 expression levels following MJ-33 treatment compared with the control group. Moreover, the expression levels of autophagy-related proteins, including autophagy related (ATG)-5, ATG-7, ATG-12, ATG-16, p62 and LC3-II, were increased following MJ-33 treatment compared with the control group. Furthermore, MJ-33-treated HT-29/5FUR cells displayed decreased expression levels of p-AKT and p-mTOR compared with control cells. The results suggested that MJ-33-induced apoptosis was mediated by AKT signaling, and subsequently modulated via the mitochondria-dependent signaling pathway. Therefore, the results suggested that suppression of AKT/mTOR activity triggered autophagy in the HT-29/5FUR cell line. In summary, the results indicated that MJ-33 inhibited HT-29/5FUR cell viability, and induced apoptosis and autophagy via the AKT/mTOR signaling pathway. The present study may provide novel insight into the anticancer effects and mechanisms underlying MJ-33 in 5FU-resistant colorectal cancer cells.

Triple-negative breast cancers (TNBCs) are associated with poor patient survival because of the absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expressions. Our previous studies have shown that the triterpenoid saponin AG8 from Ardisia gigantifolia stapf. inhibits the proliferation of MDA-MB-231 cells. In this study, the effects of AG8 were further analyzed in different TNBC cell types: MDA-MB-231, BT-549, and MDA-MB-157 cells. AG8 inhibited the viability of MDA-MB-231, BT-549, and MDA-MB-157 cells in a dose-dependent manner and showed stronger cytotoxicity to African American (AA) and mesenchymal (M) subtypes than Caucasian (CA) and mesenchymal stem-like (MSL) subtypes, respectively. AG8 impaired the uptake of MitoTracker Red CMXRos by the mitochondria of TNBC cells in a dose-dependent manner, and this was recovered by N-acetyl-l-cysteine (NAC). AG8 affected GSH, SOD, and MDA levels of TNBC cells, but different TNBC subtypes had different sensitivities to AG8 and NAC. In addition, we found that AG8 increased the Bax/Bcl-2 ratio and the levels of cytoplasmic cytochrome c and significantly decreased phosphorylation of ERK and AKT in BT549 and MDA-MB-157 cells. AG8 elicited its anticancer effects through ROS generation, ERK and AKT activation, and by triggering mitochondrial apoptotic pathways in TNBC cells. AG8 had selective cytotoxic effects against the AA and M TNBC subtypes and markedly induced MDA-MB-157 (AA subtype) cell apoptosis through pathways that were not associated with ROS, which was different from the other two subtypes. The underlying mechanisms should be further investigated.

AG36 is a triterpenoid saponin from Ardisia gigantifolia stapf. Our recent studies proved that AG36 displayed prominent cytotoxicity against breast cancer cells both in vitro and in vivo. However, whether AG36 has antiangiogenic properties is unknown. Therefore, in the present study, we evaluated the antiangiogenic effect of AG36 and the underlying mechanism. The results indicated that AG36 could significantly inhibit the proliferation, migration and invasion of human umbilical vein endothelial cells (HUVEC). Further antiangiogenic molecular mechanism investigation showed that AG36 significantly suppressed phosphorylated FAK and AKT, and downregulated the expressions of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor 2 (VEGFR2) in HUVECs. PI3K inhibitor (LY294002) and FAK inhibitor (PF562271) pretreatment could markedly enhance AG36-induced inhibition of HUVEC proliferation and p-FAK suppression, respectively. In addition, AG36 inhibited the tumor growth in xenograft model and expressions of p-VEGFR2 and p-Akt in vivo. Molecular docking simulation indicated that AG36 formed hydrogen bonds and hydrophobic interactions within the ATP binding pocket of VEGFR2 kinase domain. The present study firstly revealed the high antiangiogenic potency and related underlying molecular of AG36, demonstrating that AG36 maybe a potential antiangiogenic cancer therapy agent or lead candidate.

Hierarchical hollow structures show particular properties and promising applications, and therefore have been attracting attention. To the best of our knowledge, ZnO/C hollow sphere constructed by octahedron has not been reported so far. In this paper, a solvothermal process has been developed to prepare precursor hollow spheres constructed by octahedron. The precursor can be converted to hollow ZnO/C spheres with well-preserved morphology via thermal decomposing. In order to research the formation mechanism, intermediate precursors were acquired at different reaction times, and a possible growth mechanism was also proposed. When the hierarchical ZnO/C hollow spheres constructed by octahedron were used as the adsorbents, the Langmuir model can well describe the adsorption isotherms. For Congo red and Pb(II), the maximum adsorption capacities are up to 392 and 314 mg g−1, respectively. Furthermore, the as-prepared ZnO/C displays good recyclability in the removal of Congo red. Our results provide new strategy for the synthesis of novel ZnO/C hollow sphere, which has promising adsorption ability for water treatment.

Background: Although emerging studies have provided evidence that osteocytes are actively involved in fracture healing, there is a general lack of a detailed understanding of the mechanistic pathway, cellular events and expression of markers at different phases of healing. Methods: This systematic review describes the role of osteocytes in fracture healing from early to late phase. Literature search was performed in PubMed and Embase. Original animal and clinical studies with available English full-text were included. Information was retrieved from the selected studies. Results: A total of 23 articles were selected in this systematic review. Most of the studies investigated changes of various genes and proteins expression patterns related to osteocytes. Several studies have described a constant expression of osteocyte-specific marker genes throughout the fracture healing cascade followed by decline phase with the progress of healing, denoting the important physiological role of the osteocyte and the osteocyte lacuno-canalicular network in fracture healing. The reports of various markers suggested that osteocytes could trigger coordinated bone healing responses from cell death and expression of proinflammatory markers cyclooxygenase-2 and interleukin 6 at early phase of fracture healing. This is followed by the expression of growth factors bone morphogenetic protein-2 and cysteine-rich angiogenic inducer 61 that matched with the neo-angiogenesis, chondrogenesis and callus formation during the intermediate phase. Tightly controlled regulation of osteocyte-specific markers E11/Podoplanin (E11), dentin matrix protein 1 and sclerostin modulate and promote osteogenesis, mineralisation and remodelling across different phases of fracture healing. Stabilised fixation was associated with the finding of higher number of osteocytes with little detectable bone morphogenetic proteins expressions in osteocytes. Sclerostin-antibody treatment was found to result in improvement in bone mass, bone strength and mineralisation. Conclusion: To further illustrate the function of osteocytes, additional longitudinal studies with appropriate clinically relevant model to study osteoporotic fractures are crucial. Future investigations on the morphological changes of osteocyte lacuno-canalicular network during healing, osteocyte-mediated signalling molecules in the transforming growth factor-beta-Smad3 pathway, perilacunar remodelling, type of fixation and putative biomarkers to monitor fracture healing are highly desirable to bridge the current gaps of knowledge.The translational potential of this article: This systematic review provides an up-to-date chronological overview and highlights the osteocyte-regulated events at gene, protein, cellular and tissue levels throughout the fracture healing cascade, with the hope of informing and developing potential new therapeutic strategies that could improve the timing and quality of fracture healing in the future. Keywords: Dentin matrix protein 1, Fracture healing, Lacuno-canalicular network, Osteocyte, Sclerostin, TGF-Beta-Smad3

Aims In estuarine salt-marshes, nitrate supply and soil salinity, which are known as two main environmental drivers, simultaneously affect the interspecific interactions between plant species. However, to date, their interactive effects on interspecific interactions have not been closely examined for salt-marsh plant species. Methods Juvenile plants of Suaeda salsa L. (Chenopodiaceae) and Scirpus planiculmis Fr. (Cyperaceae) were grown in rinsed river sand to conduct a greenhouse experiment with three treatment categories: interspecific interaction (mixed culture or monoculture), three salinity levels (1, 50 and 100 mmol L−1) and three nitrate levels (0.5, 5 and 10 mmol L−1). First, height and biomass of all plants were measured. Then, the growth data, relative interaction index and competitive important index of the two species were analyzed. Important Findings The interspecific interactions between S. salsa and S. planiculmis were facilitation across the salinity gradients. The promotion of S. salsa growth with high nitrate supply did not enhance the facilitative effect of the species, especially at low salinity. However, high nitrate supply significantly shifted the interspecific interactions of S. planiculmis from facilitation to competition at high salinity. Our results suggest that excessive nitrate application changes the prediction of the stress-gradient hypothesis along a salinity gradient, leading to collapse of the two species coexistence in the salt-marshes. These findings make a contribution to the understanding of how S. salsa and S. planiculmis, as well as salt-marsh communities, respond to the human modification of estuarine nutritional levels.

Background Sarcopenia is an aging‐induced deterioration of skeletal muscle mass and function. Low‐magnitude high‐frequency vibration (LMHFV) was shown to improve muscle functions and β‐hydroxy‐β‐methylbutyrate (HMB) to increase muscle mass and strength. Muscle‐derived stem cells (MDSCs) are progenitor cells important for muscle regeneration. We hypothesized that LMHFV and HMB could retard sarcopenia by reducing fat infiltration through inhibiting adipogenesis in MDSCs. Methods Senescence‐accelerated mouse P8 male mice were randomized into control (CTL), HMB, LMHFV (VIB), and combined (COM) groups. Interventions started at age of month 7 and assessed at 1, 2, and 3 months post‐intervention by densitometry, histology, and functional tests. In vitro, MDSCs isolated from gastrocnemius of senescence‐accelerated mouse P8 mice were characterized, randomized into CTL, VIB, HMB, and COM groups, and assessed by oil red O staining, mRNA, and protein expression. Results At 2 months post‐intervention, percentage lean mass of HMB, VIB, and COM groups were significantly higher than CTL group. Twitch, tetanic, and specific tetanic forces of COM group were higher, while specific twitch force of both VIB and COM groups were higher. Grip strength of HMB, VIB, and COM groups were higher. Histologically, both VIB and COM groups presented lower oil red O area than CTL group. Type I muscle fibre in CTL group was higher than HMB, VIB, and COM groups. MDSC were detected in situ by immunofluorescence stain with stem cell antigen‐1 signals confirmed with higher β‐catenin expression in the COM group. The observations were also confirmed in vitro, MDSCs in the HMB, VIB, and COM groups presented lower adipogenesis vs. the CTL group. β‐Catenin mRNA and protein expressions were lower in the CTL group while their relationship was further validated through β‐catenin knock‐down approach. Conclusions Our results showed that combined LMHFV and HMB interventions enhanced muscle strength and decreased percentage fat mass and intramuscular fat infiltration as compared with either treatment alone. Additive effect of LMHFV and HMB was demonstrated in β‐catenin expression than either treatment in MDSCs and altered cell fate from adipogenesis to myogenesis, leading to inhibition of intramuscular lipid accumulation. Wnt/β‐catenin signalling pathway was found to be the predominant regulatory mechanism through which LMHFV and HMB combined treatment suppressed MDSCs adipogenesis.

Lithium–sulfur batteries are promising candidates for the next generation of energy storage systems owing to their high energy density, low toxicity and abundant reserves of sulfur. However, sulfur has poor conductivity, large volume change during charge/discharge, and more importantly, the intermediate polysulfide (Li2Sn, 3 ≤ n≤8) produced in the cycling process is easily soluble in the electrolyte resulting in the “shuttle effect”, which have greatly limited the commercialization of lithium–sulfur batteries. Therefore, it is of great value to develop optimized sulfur cathode materials to improve electrode conductivity, buffer volume change and restrain the diffusion of polysulfide. In this work, we construct a V-MOF (MIL-47) derived V2O3@C hollow microcuboid with a hierarchical lasagna-like structure through hydrothermal synthesis followed by calcination, and employ it as a sulfur host for the first time. The fast anchoring of polysulfide by V2O3 nanoparticles and the high electronic conductivity of the 3D carbon framework can simultaneously inhibit the “shuttle effect” in the charge–discharge process and accelerate the kinetics of the redox process. Moreover, the special lasagna-like structure with appropriate voids generated during calcination not only provides many sites for sulfur loading, but also effectively alleviates the volume expansion problem during the electrochemical reaction. Therefore, the final fabricated sulfur cathode via the melt impregnation method exhibits good cycling stability (62.3% after 1000 cycles at 1C) and rate performance (663 mA h g−1 at 2C) at a relatively high sulfur loading of 3.7 mg cm−2.

ABO3-δ perovskites are utilized in many applications including optical gas sensing for energy systems. Understanding the opto-electronic properties allows rational selection of the perovskite-based sensors from a diverse family of ABO3-δ perovskites, associated with the choices of A and B cations and range of oxygen concentrations. Herein, we assess the impact of oxygen vacancies on the electronic structure and optical response of pristine and oxygen-vacant ABO3-δ (A = La, Sr; B = Cr, Mn) perovskites via first-principles calculations. The endothermic formation energy for oxygen vacancies shows that the generation of ABO3-δ defect structures is thermodynamically possible. LaCrO3 and LaMnO3 have direct and indirect ground-state band gaps, respectively, whereas SrCrO3 and SrMnO3 are metallic. In the presence of an oxygen mono-vacancy, however, the band gap decreases in LaCrO3-δ and vanishes in LaMnO3-δ. In contrast to the decrease in the band gaps, the oxygen vacancies in ABO3-δ are found to increase optical absorption in the visible to near-infrared wavelength regime, and thus lower the onset energy of absorption compared with the pristine materials. Our assessments emphasize the role of the oxygen vacancy, or other possible oxygen non-stoichiometry defects, in perovskite oxides with respect to the opto-electronic performance parameters that are of interest for optical gas sensors for energy generation process environments.

Tomato (Solanum lycopersicum) is one of the most important greenhouse vegetables, with a large cultivated area across the world. However, in northern China, tomato plants often suffer from low-temperature stress in solar greenhouse cultivation, which affects plant growth and development and results in economic losses. We previously found that a chloroplast aldolase gene in tomato, SlFBA4, plays an important role in the Calvin-Benson cycle (CBC), and its expression level and activity can be significantly altered when subjected to low-temperature stress. To further study the function of SlFBA4 in the photosynthesis and chilling tolerance of tomato, we obtained transgenic tomato plants by the over-expression and RNA interference (RNAi) of SlFBA4. The over-expression of SlFBA4 led to higher fructose-1,6-bisphosphate aldolase activity, net photosynthetic rate (Pn) and activity of other enzymes in the CBC than wild type. Opposite results were observed in the RNAi lines. Moreover, an increase in thousand-seed weight, plant height, stem diameter and germination rate in optimal and sub-optimal temperatures was observed in the over-expression lines, while opposite effects were observed in the RNAi lines. Furthermore, over-expression of SlFBA4 increased Pn and enzyme activity and decreased malonaldehyde (MDA) content under chilling conditions. On the other hand, Pn and MDA content were more severely influenced by chilling stress in the RNAi lines. These results indicate that SlFBA4 plays an important role in tomato growth and tolerance to chilling stress.

Low-magnitude high-frequency vibration (LMHFV) has previously been reported to modulate the acute inflammatory response of ovariectomy-induced osteoporotic fracture healing. However, the underlying mechanisms are not clear. In the present study, we investigated the effect of LMHFV on the inflammatory response and the role of the p38 MAPK mechanical signaling pathway in macrophages during the healing process. A closed femoral fracture SD rat model was used. In vivo results showed that LMHFV enhanced activation of the p38 MAPK pathway at the fracture site. The acute inflammatory response, expression of inflammatory cytokines, and callus formation were suppressed in vivo by p38 MAPK inhibition. However, LMHFV did not show direct in vitro enhancement effects on the polarization of RAW264.7 macrophage from the M1 to M2 phenotype, but instead promoted macrophage enlargement and transformation to dendritic monocytes. The present study demonstrated that p38 MAPK modulated the enhancement effects of mechanical stimulation in vivo only. LMHFV may not have exerted its enhancement effects directly on macrophage, but the exact mechanism may have taken a different pathway that requires further investigation in the various subsets of immune cells.

Cholesterol is an essential compound for human health, and a high or low concentration of cholesterol is closely related to various diseases. Thus, developing a simple method for POCT of cholesterol has great significance in clinical diagnosis. In this work, alginate (Alg) hydrogels with glow-type chemiluminescence (CL) were prepared and applied for rapid and quantitative cholesterol detection via a smartphone. The glow-type CL hydrogels (HRP/COD/luminol/Alg hydrogels) contained luminol as a chemiluminescent reagent, horseradish peroxidase (HRP) and cholesterol oxidase (COD) for enzymatic cascade reactions. The HRP/COD/luminol/Alg hydrogels exhibited outstanding stability, which effectively avoided the enzyme inactivation during long-term storage. Furthermore, the HRP/COD/luminol/Alg hydrogels exhibited longer and more stable glow-type CL. With the help of COD catalytic specificity for cholesterol and bi-enzymatic cascade reactions, the glow-type CL hydrogels realized the specific and sensitive detection of cholesterol. The smartphone was used as a detector instead of a special large instrument for responding to the glow-type CL emission, and a LOD of 7.2 μM was obtained. Therefore, the proposed sensor expands the application of the glow-type CL in POCT and provides an alternative way for cholesterol detection in clinical diagnosis.

Dracorhodin can be isolated from the exudates of the fruit of Daemonorops draco. Previous studies suggested that dracorhodin perchlorate can promote fibroblast proliferation and enhance angiogenesis during wound healing. In the present study, the potential bioactivity of dracorhodin perchlorate in human HaCaT keratinocytes, were investigated in vitro, with specific focus on HaCaT wound healing. The results of in vitro scratch assay demonstrated the progressive closure of the wound after treatment with dracorhodin perchlorate in a time-dependent manner. An MTT assay and propidium iodide exclusion detected using flow cytometry were used to detect cell viability of HaCaT cells. Potential signaling pathways underlying the effects mediated by dracorhodin perchlorate in HaCaT cells were clarified by western blot analysis and kinase activity assays. Dracorhodin perchlorate significantly increased the protein expression levels of β-catenin and activation of AKT, ERK and p38 in HaCaT cells. In addition, dracorhodin perchlorate did not induce HaCaT cell proliferation but promoted cell migration. Other mechanisms may yet be involved in the dracorhodin perchlorate-induced wound healing process of human keratinocytes. In summary, dracorhodin perchlorate may serve to be a potential molecularly-targeted phytochemical that can improve skin wound healing.

Uranium and other trace elements in coal ash have received a significant attention as the beneficial reuse of hazardous wastes. In this study, combined with X-ray diffraction, field emission scanning electron microscope-energy dispersive spectroscopy and other analyses, thermochemical treatment (sodium hydroxide) and leaching trial (water, alkaline and acid solution) were conducted to evidence that elements are selectively encapsulated in Si–Al glass, eutectic and Fe-enriched fraction during combustion leading to a low extraction efficiency. Thereinto, comparing the main host of V, Cs, Rb and Sr in Si–Al glass, there are 47%, 45% and 8% of U encapsulated with Si–Al glass, eutectic and Fe-enriched fraction, while 59% of Ga remains in Si–Fe-enriched residue. Different from the large extraction of V, Cs, Rb and Ga followed by the removal of Si–Al glass and water leaching, U and Sr remained in residue with a high mobility. Overall, the leaching efficiencies of U, V, Cs, Rb, Ga and Sr were significantly improved and up to 92%, 100%, 74%, 78%, 41% and 98% respectively at the condition of NaOH/ash = 1.5, 500 °C and 1 h. Hence, it is necessary to properly handle the leachate also residue due to their potential environmental implications when the ash is employed to synthesize advanced materials.

Triphenylamine-based cyclometalated platinum(II) (TCP) emits phosphorescence at room temperature. The phosphorescence was quenched by oxygen molecule, which means that TCP is a good candidate for oxygen molecule recognition and measurement. By the way of quantum chemical calculation, we proposed the quenching mechanism to elucidate the nature of oxygen sensing, which was different from the traditional dynamic collision mechanism. The luminescence mechanism of TCP involves phosphorescent emission, and the TCP-O2 complex fluorescent emission. By utilizing the density functional theory (DFT) method, we calculated the electron configurations and the frontier molecular orbitals of TCP and the TCP-O2 complex. Furthermore, applying the time-dependent density functional theory (TDDFT) method, we calculated the geometric optimization and the excitation energies of TCP and the TCP-O2 complex in the excited state. The results illustrate that the luminescence of TCP stems from localized excitation, while that of the TCP-O2 complex stems from delocalized excitation. Moreover, we also calculated the radiative and non-radiative rate constants of TCP and the TCP-O2 complex and clarified the photophysical processes of them. For TCP, first the electron arrived at the T1 state via intersystem crossing from the initial S1 state and finally back to the S0 state via emitting phosphorescence. For the TCP-O2 complex, with no spin flip, the electron jumped directly from the T1 to T0 state via internal conversion.

The nitroso Diels—Alder (NDA) reaction has occupied an important place in organic synthesis, and numbers of important compounds and bioactive skeletons have been synthesized by this method during the past decade. Good regiocontrol and enantioselectivity of the NDA reaction allow it to have wider application. This microreview discusses the latest advances in the area of asymmetric NDA reactions and their synthetic applications since Yamamoto’s detailed summary made in 2006.

The hydrothermal reactions of Ln(NO3)3·nH2O, Cd(NO3)2·4H2O/Zn(NO3)2·4H2O, pyrazine-2,3-dicarboxylic acid (2,3-H2pzdc), and NaOH yielded a series of metal-organic coordination polymers (CPs) {[Ln2Cd(2,3-pzdc)4(H2O)6]·2H2O}n [Ln = La (1), Pr (2), Nd (3)], {[Ln2(2,3-pzdc)3(H2O)5]·3H2O}n [Ln = Eu (4), Tb (5), Dy (6), Ho (7), Er (8)], and {[Dy2Zn(2,3-pzdc)4(H2O)6]·2H2O}n (9). They were characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, powder X-ray diffraction, and thermogravimetric analysis. CPs 1–3 and 9 are isostructural and show a 3D framework formed by 2,3-pzdc linking CdII/ZnII and LnIII with a 3,3,4,4-connected {4.62}2{42.62.82}{63}2{65.8}2 topology. CPs 4–8 are isostructural and exhibit a 3D framework constructed from the 2,3-pzdc anions bridging the LnIII ions with a 3,4-connected {4.6.8}{4.62.83} topology. Introduction of the CdII ion plays an important role in the formation of 1–8. CPs 4–6 display the characteristic fluorescent emissions of EuIII, TbIII, and DyIII, respectively. CPs 6 and 9 indicate field-induced slow magnetic relaxation behaviors. A ferromagnetic coupling between the intrachain DyIII ions was observed in 9.

Due to the sintering phenomena of coal ash (CA), uranium is hardly leached even under high-concentration H2SO4 solution. It is difficult to collect and take advantage of those potential nuclear sources. In this study, the coal with high content of uranium (112.56 ug/g) was collected from Menwang, Yunan Province, Southwestern China. Sequential chemical extraction and leaching experiment were conducted. Based on X-ray diffraction and scanning electronic microscopy analysis, elements (U, V, Cs, Rb, Ga, and Sr) were surrounded by minerals during coal combustion when the temperature was over 700 °C. Therefore, thermochemical treatment with (NH4)2SO4 was used to activate the amorphous Al in CA, and led to the release of element at the following water leaching. The leaching contents of U, Cs, Rb, and Sr, under the thermochemical condition of the CA/(NH4)2SO4 = 2:4, 400 °C, and 1 h, were 1.89, 2.31, 8.39, and 1.74 times higher than directly leaching CA with 0.4 M H2SO4. Moreover, uranium was extensively leached by deionized water at the condition of solid to liquid ratio of 1:10, 60 °C, and 2 h, which was characterized by the advantages of the environment friendly, saving resources, and reducing equipment maintenance investment.

Six transition metal–organic complexes based on 3,5-di(3,4-dicarboxylphenyloxy)benzoic acid (H5L) and different N-donor co-ligands, namely, Cu(H3L)(2,2′-bpy)·H2O (1), Zn2(HL)(2,2′-bpy)2 (2), Cd2(HL)(2,2′-bpy)2(H2O) (3), Cd2(HL)(phen)4·5H2O (4), Cu(H3L)(phen) (5), and Cu(H3L)(4,4′-bpy)·H2O (6) (2,2′-bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, 4,4′-bpy = 4,4′-bipyridine), were successfully synthesized under hydrothermal conditions. Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR, powder X-ray diffraction (PXRD), and thermogravimetric analyses (TGA). Complexes 1 and 5 possess discrete zero-dimensional (0D) structures which are further assembled into three-dimensional (3D) supramolecular frameworks by hydrogen-bonding interactions and π–π stacking interactions. Complexes 2 and 3 display similar 3D frameworks with different topologies. Complex 4 shows a one-dimensional (1D) chain which is further connected into a two-dimensional (2D) supramolecular layer via π–π stacking interactions. Complex 6 exhibits a 1D chain which is further extended into a 3D supramolecular network through hydrogen-bonding interactions. The H5L ligand is partially deprotonated in 1–6. The N-donor co-ligands and transition metal ions have important effects on the architectures of 1–6. The photoluminescent properties of 2–4 and the magnetic properties of 1 and 6 were also studied.

Two new iridoids (1, 2), along with one known iridoid (3), two known triterpenoid saponins (4, 5), and one known flavonoid (6), were isolated from the whole plant of Patrinia heterophylla Bunge. Their structures were elucidated on the basis of extensive spectroscopic data analysis, especially by means of 1D and 2D NMR and HR-ESI-MS analyses. The cytotoxic activity of the isolated compounds against human leukemic cells was evaluated using CCK-8 assay. Compounds 1 and 2 showed cytotoxic activities against HL-60, K562, and Jurkat cells, and compounds 3 and 5 showed cytotoxic activity against HL-60. Among them, compound 1 showed slightly stronger cytotoxic activity against K562 cells than the positive control.

The limited stability and aggregation of colloidal nanoparticles are typically major issues in catalysis. In this work, a highly efficient polystyrene based nano-silver containing polymer (PS-AgNPs) has been synthesized as a catalyst for the reduction of 4-nitrophenol. Entanglements of polystyrene chains restrict the aggregation of AgNPs in the polymer side chains and give rise to a stable nano-silver domain size. The domain size of nano-silver in both low Ag content PS-AgNPs (L-PS-AgNPs) and high Ag content PS-AgNPs (H-PS-AgNPs) is around 15 nm (in films). No intensified Ag aggregation occurs as the Ag concentration increases. Based on kinetic measurements of the catalytic model reaction of 4-nitrophenol, the linear relationship between the rate constant kapp and different Ag concentrations in L-PS-AgNPs was extended by two orders of magnitude of the Ag concentration for the first time. These results indicated that AgNPs in L-PS-AgNPs were homogeneously distributed and exhibited excellent dispersion stability. Additionally, the catalytic performance of H-PS-AgNPs was comparable to a microreactor including the core of AgNPs/SiO2 and polymer shell. In this work, H-PS-AgNPs based on molecular entanglements were relatively simple as compared to the core/shell design of microreactors, which provided a new strategy to confine the size domain of metal nanoparticles immobilized on polymers.

To resolve the defects of acetic acid solvents for the liquid-phase oxidation of toluene to benzaldehyde with oxygen, a low-corrosive and green method was developed by introducing benzyl benzoate into the reaction. It was found that compared with the case of acetic acid, benzyl benzoate showed gratifying effect on the oxidation of toluene to benzaldehyde. The reaction was more active in the initial stage of oxidation, and the generated benzaldehyde was protected from further oxidation due to the synergistic effect of benzyl benzoate along with toluene-derived products benzyl alcohol and benzyl bromide. Benzyl benzoate inhibited the esterification of benzyl alcohol, while benzyl bromide promoted the formation of benzyl alcohol. Therefore, considerable benzyl alcohol concentration could be maintained and high benzaldehyde selectivity could be achieved under high toluene conversion.

Cystatin C (CysC)-induced autophagy may play a beneficial role in preventing subarachnoid hemorrhage-induced cerebral vasospasm. The role of CysC in endothelial cells (ECs) autophagy is unknown. This study explores the role of CysC during the process of oxidative stress in human umbilical vein endothelial cells (HUVECs). Oxidized LDL (oxLDL) was used to stimulate HUVECs in vitro study. The lactate dehydrogenase (LDH) release and malondialdehyde (MDA) level were assayed. Western blot is used to detect the expression levels of LC3 and P62. The present study demonstrated that LDH release and MDA levels increased after oxLDL exposure, however, CysC and NAC (N-acetyl-cysteine) decreased LDH release and MDA levels induced by oxLDL. The difference was a statistically significant amount (P

A three-dimensional (3D) coordination polymer (CP) constructed from the linear trinuclear Co(II) cluster and 3,5-bis(4-carboxyphenyl)pyridine (H2bcpp), Co3(bcpp)2(HCOO)2(H2O)2 (1), has been synthesized under solvothermal condition of H2O-DMF (DMF = N,N-dimethylformamide) and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). In 1, the COO groups from the bcpp and HCOO anions bridge the Co(II) ions to form a linear trinuclear Co3(COO)6 cluster. The linear trinuclear Co3(COO)6 clusters are linked by the bcpp anions into a 3D CP with a 3,6-connected (4·82)2(42·812·10) topology. The HCOO anion is derived from the decomposition of DMF under solvothermal condition. The introduction and decomposition of DMF plays an important role in the formation of 1. In addition, the photoluminescent and magnetic properties of 1 have been investigated.

Trifluoromethyl-substituted cyclometalated platinum(II) (TSCP) is a useful material for oxygen molecule detection and determination. Through quantum chemical computation, we propose a quenching mechanism to explain the nature of oxygen sensing. The luminescence mechanism of TSCP involves phosphorescent emission and the TSCP-O2 complex internal conversion. By applying the density functional theory (DFT) method, we computed the frontier molecular orbitals and electron configurations of TSCP and the TSCP-O2 complex. In addition, using the time-dependent density functional theory (TDDFT) method, we computed the excited energies and geometric optimization of the excited state of TSCP and the TSCP-O2 complex. According to the computation results, the luminescence of TSCP is due to localized excitation, while that of the TSCP-O2 complex is due to delocalized excitation. We computed the radiative and non-radiative rate constants of TSCP and the TSCP-O2 complex and elucidated their photophysical processes. For TSCP, after excitation, first the electron jumped from the S1 to T1 state by intersystem crossing, and eventually back to the S0 state by phosphorescence emission. Instead, for the TSCP-O2 complex without spin flip, the electron jumped directly from the T1 to T0 state by internal conversion.

Eight undescribed diterpenoids, euphorfinoids E-L, together with twelve known analogues, were isolated from the roots of wild Euphorbia fischeriana. Their structures and absolute configurations were elucidated by a combination of NMR, MS, ECD, and X-ray diffraction analyses. The plausible biosynthetic pathway of 1 was also proposed. The isolated compounds displayed moderate inhibitory activity against acetylcholinesterase (AChE) with 50% inhibiting concentration (IC50) values of 6.23–192.38 μM.

Secondary hormone therapy, abiraterone and enzalutamide, has improved outcomes for metastatic castration-resistant prostate cancer (mCRPC) and prolonged patients’ lives significantly. Various studies have compared the cancer-related outcomes, adverse effects, and drug-induced comorbidities in patients with mCRPC who are treated with abiraterone or enzalutamide. However, few studies have explored associations between survival and comorbidities or comprehensive analyzed newly developed comorbidities during and after secondary hormone therapy. We attempted to clarify whether the Charlson comorbidity index (CCI) overall or itemized is predictive for overall survival, and we compared newly developed comorbidities between abiraterone and enzalutamide groups. We extracted data about expenses and comorbidities for patients who have mCRPC, received abiraterone and enzalutamide and met pre-examination operation criteria between September 2016 and December 2017 from the Taiwan National Health Insurance database. A total of 1153 patients with mCRPC who received abiraterone (n = 782) or enzalutamide (n = 371) with or without previous chemotherapy were included. We used the propensity score to match confounding factors, including age, pre-existing comorbidities, and precipitating factors for comorbidity (e.g., hypertension, hyperlipidemia), to eliminate selection bias in the comparison of newly developed comorbidities. Cox regression analysis was used for overall survival. We found that enzalutamide is superior to abiraterone with regard to overall survival. Our study revealed that there is no statistically significant difference in development of new comorbidities between abiraterone and enzalutamide group. Moreover, the CCI score, rather than any single item of the CCI, was a statistically significant predictor for overall survival.

Background Drug resistance mutation (DRM)-associated virological failure has become a critical issue for ART and the elimination of HIV. Objectives To investigate the distribution characteristics of DRMs of HIV CRF01_AE, CRF07_BC and CRF08_BC, the predominant subtypes in China. Methods Patients receiving ART up to 31 August 2020 in Ganzhou in China were recruited. Full-length sequences of the HIV pol gene were amplified from patients with virological failure. DRMs and antiretroviral susceptibility were explored using the Stanford University HIV Drug Resistance Database HIVdb Program. Results Overall, 279 of 2204 patients under ART were found to have virological failure. Nine HIV subtypes were identified among 211 sequences that were amplified successfully and CRF08_BC (37.0%), CRF01_AE (26.1%) and CRF07_BC (25.6%) were the most prevalent, with mutation frequencies of 44.9% (35/78), 52.7% (29/55) and 35.2% (19/54), respectively. The most common DRMs of these three subtypes were K103N and M184V, while the mutation frequencies of M41L, D67N, K70R, K101E, V106M, Y181C, K219E, H221Y and N348I were obviously different among subtypes. The resistance levels and frequencies for antiretroviral drugs for these three subtypes were similar and resistances to nevirapine, efavirenz, lamivudine and emtricitabine were the most frequently observed. Compared with CRF01_AE and CRF07_BC, CRF08_BC had higher proportions of DRMs for NRTIs and lower frequencies of resistance to NRTIs and NNRTIs. Conclusions The distribution characteristics of DRMs of HIV CRF01_AE, CRF07_BC and CRF08_BC were inconsistent and should be considered when selecting antiretroviral strategies, developing new drugs and controlling HIV strains containing DRMs.

The relationship between circular RNAs (circRNAs) and many types of cancer has been of great interest. A novel circRNA, circBFAR, has been identified, but the functions of circBFAR and its underlying mechanism in gastric cancer (GC) have not been reported. This study was designed to investigate the role of circBFAR in GC and its downstream miRNA targets. Quantitative real-time polymerase reaction was used to detect the expression of circBFAR and miRNAs. Cell counting kit-8 and EdU were used to detect the proliferation of GC cells. Measurement of the extracellular acidification rate, oxygen consumption rate and lactate acid production were performed to assess the glycolysis levels. The results showed that circBFAR exhibited higher expression in GC tissues and cell lines. circBFAR was proven to promote GC proliferation by targeting the miR-513a-3p/hexokinase 2 (HK2) axis. Inhibition of circBFAR also led to a significant decrease in the glycolysis levels. In this study, we found a circBFAR/miR-513a-3p/HK2 axis in GC and revealed the relationship between circBFAR and glycolysis for the first time. circBFAR may serve as a novel target of GC individualized therapy.

BackgroundAvascular necrosis of femoral head（ANFH）is a common disease in orthopedics, which seriously affects the quality of life of patients. At present, there is no clear method to solve it in clinical practice. In order to cope with this worldwide problem, many scholars have devoted themselves to the research on the treatment of ANFH. Promoting the osteogenic differentiation and directed migration of stem cells is one of the main ideas for the treatment of ANFH. In recent years, more and more researches have begun to pay attention to Chinese medicine and Chinese medicine extracts. At present, in the field of bone regeneration, epimedium is the most in-depth study of Chinese herbal medicine, and Icariin is one of the main active ingredients of epimedium. MethodsDifferent concentrations of Icariin were applied to bone marrow mesenchymal stem cells (BMSCs), and the optimal concentration of Icariin to promote osteogenic differentiation and migration of BMSCs was observed. Then the exosomes from osteoblasts were combined with the optimal concentration of Icariin to BMSCs, observe the effect of promoting osteogenic differentiation and migration of BMSCs. Using high-throughput sequencing, analyze the composition of osteoblast-derived exosomes, predict the target miRNA, and then use miRNA minic and inhibitor to verify. ResultsThe optimal concentration of Icariin to promote osteogenic differentiation and migration of BMSCs is 1×10-7 M. Icariin combined with osteoblast-derived exosomes can effectively promote the osteogenic differentiation and migration of BMSCs. The top four miRNAs which content in osteoblast-derived exosomes are let-7a-5p, miR-100-5p, miR-21-5p, miR-122-5p, and analysis shows that miR-122-5p is related to osteogenic differentiation , The verification found that miR-122-5p can significantly promote the osteogenic differentiation and migration of BMSCs. ConclusionsIcariin can clearly promote the osteogenic differentiation and migration of BMSCs, and osteoblast-derived exosomes can also effectively promote the osteogenic differentiation and migration of BMSCs, the combination of Icariin and osteoblast-derived exosomes can enhance this effect. In this process, one of its targets is miR-122-5p.

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with poor patient prognosis. A cellular stress response mechanism called the unfolded protein response (UPR) has been implicated in PDAC progression. More recently, nucleobindin 1 (NUCB1), a calcium-binding protein, has been shown to control the UPR but its precise role in PDAC has not been explored. Here, we found that downregulation of NUCB1 was associated with poor prognosis in patients with PDAC. Functionally, NUCB1 overexpression suppressed pancreatic cancer cell proliferation and showed additive effects with gemcitabine (GEM)in vitroandin vivo. Moreover, by controlling ATF6 activity, NUCB1 overexpression suppressed GEM-induced UPR and autophagy. Last but not least, we uncovered METTL3-mediated m6A modification on NUCB1 5′UTR via the reader YTHDF2 as a mechanism for NUCB1 downregulation in PDAC. Taken together, our study revealed crucial functions of NUCB1 in suppressing proliferation and enhancing the effects of gemcitabine in pancreatic cancer cells and identified METTL3-mediated m6A modification as a mechanism for NUCB1 downregulation in PDAC.