Extraction of Dibenzyl Disulfide from Transformer Oils by Acidic Ionic Liquid.

In recent years, dibenzyl disulfide (DBDS) in transformer oils has caused many transformer failures around the world, and its removal has attracted more attention. In this work, nine imidazolium-based ionic liquids (ILs) were applied as effective, green desulfurization extractants for DBDS-containing transformer oil for the first time. The results show that the desulfurization ability of the ILs for DBDS followed the order of [BMIM]FeCl4 > [BMIM]N(CN)2 > [BMIM]SCN > [BMIM](C4H9O)2PO2 > [BMIM]MeSO4 > [BMIM]NTf2 > [BMIM]OTf > [BMIM]PF6 > [BMIM]BF4. Especially, [BMIM]FeCl4 ionic liquid had excellent removal efficiency for DBDS, with its S partition coefficient KN (S) being up to 2642, which was much higher than the other eight imidazolium-based ILs. Moreover, the extractive performance of [BMIM]FeCl4 increased with an increasing molar ratio of FeCl3 to [BMIM]Cl, which was attributed to its Lewis acidity and fluidity. [BMIM]FeCl4 ionic liquid could also avail in the desulfurization of diphenyl sulfide (DPS) from model oils. The experimental results demonstrate that π-π action, π-complexation, and Lewis acid-base interaction played important roles in the desulfurization process. Finally, the ([BMIM]FeCl4) ionic liquid could be recycled five times without a significant decrease in extractive ability.

Genome-Wide Identification of the 14-3-3 Gene Family and Its Involvement in Salt Stress Response through Interaction with NsVP1 in Nitraria sibirica Pall.

14-3-3 proteins are widely distributed in eukaryotic cells and play an important role in plant growth, development, and stress tolerance. This study revealed nine 14-3-3 genes from the genome of Nitraria sibirica Pall., a halophyte with strong salt tolerance. The physicochemical properties, multiple sequence alignment, gene structure and motif analysis, and chromosomal distributions were analyzed, and phylogenetic analysis, cis-regulatory elements analysis, and gene transcription and expression analysis of Ns14-3-3s were conducted. The results revealed that the Ns14-3-3 gene family consists of nine members, which are divided into two groups: ε (four members) and non-ε (five members). These members are acidic hydrophilic proteins. The genes are distributed randomly on chromosomes, and the number of introns varies widely among the two groups. However, all genes have similar conserved domains and three-dimensional protein structures. The main differences are found at the N-terminus and C-terminus. The promoter region of Ns14-3-3s contains multiple cis-acting elements related to light, plant hormones, and abiotic stress responses. Transcriptional profiling and gene expression pattern analysis revealed that Ns14-3-3s were expressed in all tissues, although with varying patterns. Under salt stress conditions, Ns14-3-3 1a, Ns14-3-3 1b, Ns14-3-3 5a, and Ns14-3-3 7a showed significant changes in gene expression. Ns14-3-3 1a expression decreased in all tissues, Ns14-3-3 7a expression decreased by 60% to 71% in roots, and Ns14-3-3 1b expression increased by 209% to 251% in stems. The most significant change was observed in Ns14-3-3 5a, with its expression in stems increasing by 213% to 681%. The yeast two-hybrid experiments demonstrated that Ns14-3-3 5a interacts with NsVP1 (vacuolar H+-pyrophosphatase). This result indicates that Ns14-3-3 5a may respond to salt stress by promoting ionic vacuole compartmentalization in stems and leaves through interactions with NsVP1. In addition, N. sibirica has a high number of stems, allowing it to compartmentalize more ions through its stem and leaf. This may be a contributing factor to its superior salt tolerance compared to other plants.

Size-Related Pathway Flux Analysis of Ultrasmall Iron Oxide Nanoparticles in Macrophage Cell RAW264.7 for Safety Evaluation.

The endocytosis, intracellular transport, and exocytosis of different-sized nanoparticles were reported to greatly affect their efficacy and biosafety. The quantitation of endocytosis and exocytosis as well as subcellular distribution of nanoparticles might be an effective approach based on transport pathway flux analysis. Thus, the key parameters that could present the effects of three different-sized ultrasmall iron oxide nanoparticles (USIONPs) were systematically investigated in RAW264.7 cells. The endocytosis and exocytosis of USIONPs were related to their sizes; 15.4 nm of S2 could be quickly and more internalized and excreted in comparison to S1 (7.8 nm) and S3 (30.7 nm). In RAW264.7 cells, USIONPs were observed in endosomes, lysosomes, the Golgi apparatus, and autophagosomes via a transmission electron microscope. Based on flux analysis of intracellular transport pathways of USIONPs, it was found that 43% of S1, 40% of S2, and 44% of S3 were individually transported extracellularly through the Golgi apparatus-involved middle-fast pathway, while 24% of S1, 23% of S2, and 26% of S3 were transported through the fast recycling endosomal pathway, and the residues were transported through the slower speed lysosomal pathway. USIONPs might be transported via size-related endocytosis and exocytosis pathways. The pathway flux could be calculated on the basis of disturbance analysis of special transporters as well as their coding genes. Because there were rate differences among these transport pathways, this pathway flux could anticipate the intracellular remaining time and distribution of different-sized nanoparticles, the function exertion, and side effects of nanomaterials. The size of the nanomaterials could be optimized for improving functions and safety.

Positive interactions among Corynebacterium glutamicum and keystone bacteria producing SCFAs benefited T2D mice to rebuild gut eubiosis.

Accumulating evidences strongly support the correlations between the compositions of gut microbiome and therapeutic effects on Type 2 diabetes (T2D). Notably, gut microbes such as Akkermansia muciniphila are found able to regulate microecological balance and alleviate dysmetabolism of mice bearing T2D. In order to search out similarly functional bacteria, bacteriophage MS2 with a good specificity to bacteria carrying fertility (F) factor were used to treat T2D mice. Based on multi-omics analysis of microbiome and global metabolism of mice, we observed that gavage of bacteriophage MS2 and metformin led to a significant increase in the abundance of Corynebacterium glutamicum and A. muciniphila, respectively. Consequently, the gut microbiota were remodeled, leading to variations in metabolites and a substantial increase in short-chain fatty acids (SCFAs). In which, the amount of acetate, propionate, and butyrate presented negative correlations to that of proinflammatory cytokines, which was beneficial to repairing the intestinal barriers and improving their functions. Moreover, main short fatty acid (SCFA) producers exhibited positive interactions, further facilitating the restoration of gut eubiosis. These findings revealed that C. glutamicum and its metabolites may be potential dietary supplements for the treatment of T2D. Moreover, our research contributes to a novel understanding of the underlying mechanism by which functional foods exert their anti-diabetic effects.

Synthesis of gem-dibromo 1,3-oxazines by NBS-mediated electrophilic cyclization of propargylic amides.

We present a highly efficient and practical method for synthesizing gem-dibromo 1,3-oxazines through 6-endo-dig cyclization of propargylic amides, using N-bromosuccinimide (NBS) as an electrophilic source. The metal-free reaction can be conducted under mild conditions with good functional group compatibility, delivering excellent yields of the desired products. Mechanistic studies suggest that the reaction proceeds via a double electrophilic attack by NBS on the propargylic amide substrate.

Integrated metabolome and transcriptome analysis unveils novel pathway involved in the fruit coloration of Nitraria tangutorum Bobr.

BACKGROUND: The desert shrub Nitraria tangutorum Bobr. is important for its resistance to salt and alkali in Northwest China. It is an ecologically important species in this region and provides edible and medicinal berries. This study showed a mutant of N. tangutorum (named Jincan, JC) that has a strong yellow pericarp vs red in a wild type (represented by NT). RESULTS: In this study, the secondary metabolic and molecular mechanisms responsible for Nitraria fruit coloration were investigated using LC-MS-based widely targeted metabolomics and transcriptomics data. As a result of our study, 122 and 104 flavonoid metabolites were differentially expressed throughout the mature and transition stages between JC and NT, respectively. Furthermore, two cyanidin derivatives (cyanidin 3-O-glucoside and cyanidin-3-O-(2''-O-glucosyl) glucoside) and one pelargonidin derivative (pelargonidin-3-O-glucoside) were identified only in the NT phenotype. The functional genes F3H (flavanone 3-hydroxylase), F3'H (flavonoid 3'-hydroxylase) and UFGT (flavonoid 3-O-glucosyltransferase) and the transcription factors MYB, bHLH, NAC and bZIP were significantly downregulated in JC. Meanwhile, the activity of UFGT was extremely low in both periods of JC, with a five-fold higher enzymatic activity of UFGT in RT than in YT. In summary, due to the lack of catalysis of UGFT, yellow fruit of JC could not accumulate sufficient cyanidin and pelargonidin derivatives during fruit ripening. CONCLUSION: Taken together, our data provide insights into the mechanism for the regulation of anthocyanin synthesis and N. tangutorum fruit coloration and provide a theoretical basis to develop new strategies for developing bioactive compounds from N. tangutorum fruits.

Selection and validation of appropriate reference genes for RT-qPCR analysis of Nitraria sibirica under various abiotic stresses.

BACKGROUND: Nitraria sibirica Pall. is a halophytic shrub with strong environmental adaptability that can survive in extremely saline-alkali and drought-impacted environments. Gene expression analysis aids in the exploration of the molecular mechanisms of plant responses to abiotic stresses. RT-qPCR is the most common technique for studying gene expression. Stable reference genes are a prerequisite for obtaining accurate target gene expression results in RT-qPCR analysis. RESULTS: In this study, a total of 10 candidate reference genes were selected from the transcriptome of N. sibirica, and their expression stability in leaves and roots under different treatment conditions (salt, alkali, drought, cold, heat and ABA) was evaluated with the geNorm, NormFinder, BestKeeper, comparative ΔCt and RefFinder programs. The results showed that the expression stability of the candidate reference genes was dependent on the tissue and experimental conditions tested. ACT7 combined with R3H, GAPDH, TUB or His were the most stable reference genes in the salt- or alkali-treated leaves, salt-treated roots and drought-treated roots, respectively; R3H and GAPDH were the most suitable combination for drought-treated leaves, heat-treated root samples and ABA-treated leaves; DIM1 and His maintained stable expression in roots under alkali stress; and TUB combined with R3H was stable in ABA-treated roots. TBCB and GAPDH exhibited stable expression in heat-treated leaves; TBCB, R3H, and ERF3A were stable in cold-treated leaves; and the three most stable reference genes for cold-treated roots were TBCB, ACT11 and DIM1. The reliability of the selected reference genes was further confirmed by evaluating the expression patterns of the NsP5CS gene under the six treatment conditions. CONCLUSION: This study provides a theoretical reference for N. sibirica gene expression standardization and quantification under various abiotic stress conditions and will help to reveal the molecular mechanisms that confer stress tolerance to N. sibirica.

Influence of the pendant groups on electrochemical water oxidation catalyzed by cobalt(II) triazolylpyridine complexes.

The development of low-cost catalysts for the water oxidation reaction (WOR) is important for solving the bottleneck issues in water splitting and benefits the widespread utilization of renewable energy sources. Herein, four cobalt(II) triazolylpyridine complexes, namely [Co(DTE)2(H2O)2](ClO4)2·CH3COCH3 (1), [Co(DTE)2Cl2]·2CH3OH (2) (DTE = (1-(2-acetoxymethyl)-4-(2-pyridyl)1,2,3-triazole), [Co(DTEL)2(CH3OH)2](ClO4)2 (3), and [Co(DTEL)2Cl2]·H2O (4) (DTEL = (1-(2-hydroxy)-4-(2-pyridyl)1,2,3-triazole), were synthesized and characterized. The crystal structures of 1-3 were determined by X-ray single crystal diffraction analysis. The electrocatalytic water oxidation by 1-4 was studied in 0.1 M NaOAc-HOAc solutions. Complexes 1-4 were single-site molecular catalysts for the WOR under near-neutral conditions. The overpotentials for the WOR were 440 mV and 480 mV. The faradaic efficiencies were 77-92%. The rate constants kcat were 0.21-0.96 s-1. The catalytic activities were affected by the pendant groups of DTE and DTEL. Complexes with DTE (1 and 2) showed better activities than those with DTEL (3 and 4). Moreover, complexes 1-4 adsorbed on indium-doped tin oxide (ITO) and glassy carbon electrode surfaces were active for the WOR. A mechanism was proposed for the WOR catalyzed by 1-4.

Full-Length Transcriptome Analysis of the Halophyte Nitraria sibirica Pall.

BACKGROUND: Nitraria sibirica Pall. is one of the pioneer tree species in saline-alkali areas due to its extreme salt tolerance. However, the lack of information on its genome limits the further exploration of the molecular mechanisms in N. sibirica under salt stress. METHODS: In this study, we used single-molecule real-time (SMRT) technology based on the PacBio Iso-Seq platform to obtain transcriptome data from N. sibirica under salt treatment for the first time, which is helpful for our in-depth analysis of the salt tolerance and molecular characteristics of N. sibirica. RESULTS: Our results suggested that a total of 234,508 circular consensus sequences (CCSs) with a mean read length of 2121 bp were obtained from the 19.26 Gb raw data. Furthermore, based on transcript cluster analysis, 93,713 consensus isoforms were obtained, including 92,116 high-quality isoforms. After removing redundant sequences, 49,240 non-redundant transcripts were obtained from high-quality isoforms. A total of 37,261 SSRs, 1816 LncRNAs and 47,314 CDSs, of which 40,160 carried complete ORFs, were obtained. Based on our transcriptome data, we also analyzed the coding genes of H+-PPase, and the results of both bioinformatics and functional analyses indicated that the gene prediction via full-length transcripts obtained by SMRT technology is reliable and effective. In summary, our research data obtained by SMRT technology provides more reliable and accurate information for the further analysis of the regulatory network and molecular mechanism of N. sibirica under salt stress.

PtrHAT22, as a higher hierarchy regulator, coordinately regulates secondary cell wall component biosynthesis in Populus trichocarpa.

Homeodomain-leucine zipper (HD-Zip) II transcription factors (TFs) have been reported to play vital roles in diverse biological processes of plants. However, it remains unclear whether HD-Zip II TFs regulate secondary cell wall (SCW) in woody plants. In this study, we performed the functional characterization of a Populus trichocarpa HD-Zip II TF, PtrHAT22, which encodes a nuclear localized transcription repressor predominantly expressing in secondary developing tissues. Overexpression of PtrHAT22 showed arrested growths, including reduced heights and diameters above the ground, small leaves, and decreased biomass. Meanwhile, the contents of lignin, cellulose, and thickness of SCW significantly decreased, whilst the content of hemicellulose obviously increased in PtrHAT22 transgenic poplar. The expressions of some wood-associated TFs and structural genes significantly changed accordingly with the alternations of SCW characteristics in PtrHAT22 transgenic poplar. Furthermore, PtrHAT22 directly repressed the promoter activities of PtrMYB20, PtrMYB28, and PtrCOMT2, and bind two cis-acting elements that were specifically enriched in their promoter regions. Taken together, our results suggested that PtrHAT22, as a higher hierarchy TF like PtrWNDs, exerted coordination regulation of poplar SCW component biosynthesis through directly and indirectly regulating structural genes and different hierarchy TFs of SCW formation network.

Transcriptome-wide identification and characterization of microRNAs in diverse phases of wood formation in Populus trichocarpa.

We applied miRNA expression profiling method to Populus trichocarpa stems of the three developmental stages, primary stem (PS), transitional stem (TS), and secondary stem (SS), to investigate miRNA species and their regulation on lignocellulosic synthesis and related processes. We obtained 892, 872, and 882 known miRNAs and 1727, 1723, and 1597 novel miRNAs, from PS, TS, and SS, respectively. Comparisons of these miRNA species among different developmental stages led to the identification of 114, 306, and 152 differentially expressed miRNAs (DE-miRNAs), which had 921, 2639, and 2042 candidate target genes (CTGs) in the three respective stages of the same order. Correlation analysis revealed 47, 439, and 71 DE-miRNA-CTG pairs of high negative correlation in PS, TS, and SS, respectively. Through biological process analysis, we finally identified 34, 6, and 76 miRNA-CTG pairs from PS, TS, and SS, respectively, and the miRNA target genes in these pairs regulate or participate lignocellulosic biosynthesis-related biological processes: cell division and differentiation, cell wall modification, secondary cell wall biosynthesis, lignification, and programmed cell death processes. This is the first report on an integrated analysis of genome-wide mRNA and miRNA profilings during multiple phases of poplar stem development. Our analysis results imply that individual miRNAs modulate secondary growth and lignocellulosic biosynthesis through regulating transcription factors and lignocellulosic biosynthetic pathway genes, resulting in more dynamic promotion, suppression, or regulatory circuits. This study advanced our understanding of many individual miRNAs and their essential, diversified roles in the dynamic regulation of secondary growth in woody tree species.

Comprehensive transcriptome and metabolome profiling reveal metabolic mechanisms of Nitraria sibirica Pall. to salt stress.

Nitraria sibirica Pall., a typical halophyte that can survive under extreme drought conditions and in saline-alkali environments, exhibits strong salt tolerance and environmental adaptability. Understanding the mechanism of molecular and physiological metabolic response to salt stress of plant will better promote the cultivation and use of halophytes. To explore the mechanism of molecular and physiological metabolic of N. sibirica response to salt stress, two-month-old seedlings were treated with 0, 100, and 400 mM NaCl. The results showed that the differentially expressed genes between 100 and 400 mmol L-1 NaCl and unsalted treatment showed significant enrichment in GO terms such as binding, cell wall, extemal encapsulating structure, extracellular region and nucleotide binding. KEGG enrichment analysis found that NaCl treatment had a significant effect on the metabolic pathways in N. sibirica leaves, which mainly including plant-pathogen interaction, amino acid metabolism of the beta alanine, arginine, proline and glycine metabolism, carbon metabolism of glycolysis, gluconeogenesis, galactose, starch and sucrose metabolism, plant hormone signal transduction and spliceosome. Metabolomics analysis found that the differential metabolites between the unsalted treatment and the NaCl treatment are mainly amino acids (proline, aspartic acid, methionine, etc.), organic acids (oxaloacetic acid, fumaric acid, nicotinic acid, etc.) and polyhydric alcohols (inositol, ribitol, etc.), etc. KEGG annotation and enrichment analysis showed that 100 mmol L-1 NaCl treatment had a greater effect on the sulfur metabolism, cysteine and methionine metabolism in N. sibirica leaves, while various amino acid metabolism, TCA cycle, photosynthetic carbon fixation and sulfur metabolism and other metabolic pathways have been significantly affected by 400 mmol L-1 NaCl treatment. Correlation analysis of differential genes in transcriptome and differential metabolites in metabolome have found that the genes of AMY2, BAM1, GPAT3, ASP1, CML38 and RPL4 and the metabolites of L-cysteine, proline, 4-aminobutyric acid and oxaloacetate played an important role in N. sibirica salt tolerance control. This is a further improvement of the salt tolerance mechanism of N. sibirica, and it will provide a theoretical basis and technical support for treatment of saline-alkali soil and the cultivation of halophytes.

Characterization of a High Hierarchical Regulator, PtrGATA12, Functioning in Differentially Regulating Secondary Wall Component Biosynthesis in Populus trichocarpa.

In plants, GATA transcription factors (TFs) have been reported to play vital roles in to a wide range of biological processes. To date, there is still no report about the involvement and functions of woody plant GATA TFs in wood formation. In this study, we described the functional characterization of a Populus trichocarpa GATA TF, PtrGATA12, which encodes a nuclear-localized transcriptional activator predominantly expressing in developing xylem tissues. Overexpression of PtrGATA12 not only inhibited growths of most phenotypic traits and biomass accumulation, but also altered the expressions of some master TFs and pathway genes involved in secondary cell wall (SCW) and programmed cell death, leading to alternated SCW components and breaking forces of stems of transgenic lines. The significant changes occurred in the contents of hemicellulose and lignin and SCW thicknesses of fiber and vessel that increased by 13.5 and 10.8%, and 20.83 and 11.83%, respectively. Furthermore, PtrGATA12 bound directly to the promoters of a battery of TFs and pathway genes and activated them; the binding sites include two cis-acting elements that were specifically enriched in their promoter regions. Taken together, our results suggest PtrGATA12, as a higher hierarchical TF on the top of PtrWND6A, PtrWND6B, PtrMYB152, and PtrMYB21, exert a coordinated regulation of SCW components biosynthesis pathways through directly and indirectly controlling master TFs, middle-level TFs, and further downstream pathway genes of the currently known hierarchical transcription network that governs SCW formation.

Tissue tolerance mechanisms conferring salinity tolerance in a halophytic perennial species Nitraria sibirica Pall.

Plant salt tolerance relies on a coordinated functioning of different tissues and organs. Salinity tissue tolerance is one of the key traits that confer plant adaptation to saline environment. This trait implies maintenance low cytosolic Na+/K+ ratio in metabolically active cellular compartments. In this study, we used Nitraria sibirica Pall., a perennial woody halophyte species, to understand the mechanistic basis of its salinity tissue tolerance. The results showed that the growth of seedlings was stimulated by 100-200 mM NaCl treatment. The ions distribution analysis showed that the leaves act as an Na+ sink, while the plant roots possess superior K+ retention. The excessive Na+ absorbed from the soil was mainly transported to the shoot and was eventuallysequestrated into mesophyll vacuoles in the leaves. As a result, N. sibirica could keep the optimal balance of K+/Na+ at a tissue- and cell-specific level under saline condition. To enable this, N. sibirica increased both vacuolar H+-ATPase and H+-PPase enzymes activities and up-regulated the expressions of NsVHA, NsVP1 and NsNHX1 genes. Vacuolar Na+ sequestration in the leaf mesophyll, mediated by NsVHA, NsVP1 and NsNHX1, reduced the Na+ concentration in cytosol and inhibited further K+ loss. Meanwhile, N. sibirica enhanced the Two Pore K+ expression at the transcriptional level to promote K+ efflux from vacuole into cytoplasm, assisting in maintaining cytosolic K+ homeostasis. It is concluded that the tissue tolerance traits such as vacuolar Na+ sequestration and intracellular K+ homeostasis are critical to confer adaptation of N. sibirica to soil salinity.

DNA methylation and its effects on gene expression during primary to secondary growth in poplar stems.

BACKGROUND: As an important epigenetic mark, 5-methylcytosine (5mC) methylation is involved in many DNA-dependent biological processes and plays a role during development and differentiation of multicellular organisms. However, there is still a lack of knowledge about the dynamic aspects and the roles of global 5mC methylation in wood formation in tree trunks. In this study, we not only scrutinized single-base resolution methylomes of primary stems (PS), transitional stems (TS), and secondary stems (SS) of Populus trichocarpa using a high-throughput bisulfite sequencing technique, but also analyzed the effects of 5mC methylation on the expression of genes involved in wood formation. RESULTS: The overall average percentages of CG, CHG, and CHH methylation in poplar stems were ~ 53.6%, ~ 37.7%, and ~ 8.5%, respectively, and the differences of 5mC in genome-wide CG/CHG/CHH contexts among PS, TS, and SS were statistically significant (p < 0.05). The evident differences in CG, CHG, and CHH methylation contexts among 2 kb proximal promoters, gene bodies, and 2 kb downstream regions were observed among PS, TS, and SS. Further analysis revealed a perceptible global correlation between 5mC methylation levels of gene bodies and transcript levels but failed to reveal a correlation between 5mC methylation levels of proximal promoter regions and transcript levels. We identified 653 and 858 DMGs and 4978 and 4780 DEGs in PS vs TS and TS vs SS comparisons, respectively. Only 113 genes of 653 DMGs and 4978 DEGs, and 114 genes of 858 DMGs and 4780 DEG were common. Counterparts of some of these common genes in other species, including Arabidopsis thaliana, are known to be involved in secondary cell wall biosynthesis and hormone signaling. This indicates that methylation may directly modulate wood formation genes and indirectly attune hormone signaling genes, which in turn impact wood formation. CONCLUSIONS: DNA methylation only marginally affects pathway genes or regulators involved in wood formation, suggesting that further studies of wood formation should lean towards the indirect effects of methylation. The information and data we provide here will be instrumental for understanding the roles of methylation in wood formation in tree species.

Albumin-gated zwitterion-stabilized mesoporous silica nanorod as a pH-responsive drug delivery system.

Silica nanoparticles as drug delivery systems (DDS) have received huge attention in nanomedicine research. However, their drug release processes were usually discussed in the absence of proteins, which are abundant in real delivery media and likely to affect the release behaviors. In this work, novel pH-sensitive silica-based DDSs were constructed using the endogenous protein, human serum albumin (HSA), as the gatekeeper, and their release properties in protein-containing media were measured for the first time. As-synthesized mesoporous silica nanorod (MSNR) was modified with zwitterions to suppress the nonspecific adsorption of protein and to improve the dispersity. HSA was fixed onto MSNR through drug-protein interactions and covalent bonds, respectively. Benzoic-imine bonds were introduced into the designs to realize pH responsiveness. The fluorescence quenching effect of drugs on HSA was used to monitor the drug release in simulated body fluids containing proteins. The results indicated that protein gating could effectively reduce premature release in normal blood environment. The endogenous protein capping, high dispersity and stability, considerable loading content, low cytotoxicity and favorable responsiveness to acidic microenvironment enable the present structures to be promising carriers for chemotherapy drugs.

miRNA-mRNA Integrated Analysis Reveals Roles for miRNAs in a Typical Halophyte, Reaumuria soongorica, during Seed Germination under Salt Stress.

MicroRNAs (miRNAs) are endogenous small RNAs that play a crucial role in plant growth, development, and environmental stress responses. Reaumuria soongorica is a typical halophyte that is widely distributed in saline-alkali desert regions. Under salt stress, R. soongorica can complete germination, a critical biological process in the life cycle of seed plants. To identify miRNAs and predict target mRNAs involved in seed germination during salt stress, nine small-RNA libraries were constructed and analyzed from R. soongorica seeds treated with various concentrations of NaCl. We also obtained transcriptome data under the same treatment conditions. Further analysis identified 88 conserved miRNAs representing 25 defined families and discovered 13 novel miRNAs from nine libraries. A co-expression analysis was performed on the same samples to identify putative miRNA-mRNA interactions that were responsive to salt stress. A comparative analysis of expression during germination under 273 (threshold) and 43 mM (optimal) NaCl treatments identified 13 differentially expressed miRNAs and 23 corresponding target mRNAs, while a comparison between 43 mM NaCl and non-salt-stress conditions uncovered one differentially expressed miRNA and one corresponding target mRNA. These results provide basic data for further study of molecular mechanisms involved in the germination of salt-stressed R. soongorica seeds, and also provide a reference for the improvement of salt tolerance during plant germination.

Effect of carbamylation on the molecular recognition action of amino benzothiazole by carrier protein.

Increasing benzothiazole derivatives containing amino or N-acyl structures in position 2 have been largely developed as pesticides and medicines. However, the structure-function relationship of 2-substituted benzothiazole derivatives has seldom been illustrated from the perspective of their albumin-binding nature. Herein, to probe the influence of carbamylation on the albumin-binding nature of benzothiazole derivatives, formyl group was introduced to the amine group of 2-amino benzothiazole (ABT) to yield a novel modified ABT (MABT). Their protein-binding properties were systematically deciphered by spectroscopy, molecular modeling and density functional theory (DFT) calculations. The interaction mechanisms, recognition thermodynamics and binding geometry were investigated and compared. The structural alteration of human serum albumin was explored using synchronous fluorescence emission and circular dichroism spectrum technologies. Based on experimental results, the structures of protein complex with MABT and ABT were revealed by molecular docking method. The differences in energy transfer efficiency and molecular orientation of ABT and MABT in new complexes were tentatively explained by DFT calculations. The work was expected to help to understand the impact of different substituents on the bioactivity of benzothiazole derivatives and guide for structural designs of new compounds.

Novel Quinoline-based Ir(III) Complexes Exhibit High Antitumor Activity in Vitro and in Vivo.

Eight novel Ir(III) complexes listed as [Ir(H-P)2(P)]PF6 (PyP-Ir), [Ir(H-P)2(dMP)]PF6 (PydMP-Ir), [Ir(H-P)2(MP)]PF6 (PyMP-Ir), [Ir(H-P)2(tMP)]PF6 (PytMP-Ir), [Ir(MPy)2(P)]PF6 (MPyP-Ir), [Ir(MPy)2(dMP)]PF6 (MPydMP-Ir), [Ir(MPy)2(MP)]PF6 (MPyMP-Ir), [Ir(MPy)2((tMP)]PF6 (MPytMP-Ir) with 2-phenylpyri-dine (H-P) and 3-methyl-2-phenylpyridine (MPy) as ancillary ligands and pyrido-[3,2-a]-pyrido[1',2':1,2]imidazo[4,5-c]phenazine (P), 12,13-dimethyl pyrido-[3,2-a]-pyrido[1',2':1,2]-imidazo-[4,5-c]-phenazine (dMP), 2-methylpyrido [3,2-a]-pyrido-[1',2':1,2]-imidazo-[4,5-c]-phenazine (MP), and 2,12,13-trimethylpyrido-[3,2-a]-pyrido-[1',2':1,2]-imidazo-[4,5-c]-phenazine (tMP) as main ligands, respectively, were designed and synthesized to fully characterize and explore the effect of their toxicity on cancer cells. Cytotoxic mechanism studies demonstrated that the eight Ir(III) complexes exhibited highly potent antitumor activity selectively against cancer cell lines NCI-H460, T-24, and HeLa, and no activity against HL-7702, a noncancerous cell line. Among the eight Ir(III) complexes, MPytMP-Ir exhibited the highest cytotoxicity with an IC50 = 5.05 ± 0.22 nM against NCI-H460 cells. The antitumor activity of MPytMP-Ir in vitro could be contributed to the steric or electronic effect of the methyl groups, which induced telomerase inhibition and damaged mitochondria in NCI-H460 cells. More importantly, MPytMP-Ir displayed a superior inhibitory effect on NCI-H460 xenograft in vivo than cisplatin. Our work demonstrates that MPytMP-Ir could potentially be developed as a novel potent Ir-based antitumor drug.

Down syndrome with primary thyroid diffuse large B-cell lymphoma and Hashimoto thyroiditis: A CARE compliant case report.

RATIONALE: Adult patients with Down syndrome (DS) commonly develop Hashimoto thyroiditis (HT). However, primary diffuse large B-cell lymphoma (DLBCL) of the thyroid is uncommon, and its simultaneous occurrence with HT is very rare. To our knowledge, coexisting DLBCL and HT in a patient with DS has not been reported in the medical literature. PATIENT CONCERNS: We present a 43-year-old woman with DS who reported progressive swelling of the neck on the right side and dyspnea over the previous 1 month, with associated neck ache, hoarseness, and dysphagia. Thyroid ultrasonography and computed tomography of the neck revealed a large mass in the right lobe compressing the surrounding tissues. DIAGNOSES: Based on the clinical and histopathologic findings, the patient was diagnosed with coexisting primary thyroid DLBCL and HT. INTERVENTIONS: A palliative unilateral thyroidectomy was performed; postoperative histopathology and immunohistochemistry revealed thyroid DLBCL and HT. The patient was scheduled for chemotherapy and targeted therapy after recovering from surgery. OUTCOMES: The patient died 3 weeks after surgery due to asphyxia caused by uncontrollable growth of recurrent tumor. LESSONS: The coexistence of DS, primary thyroid DLBCL, and HT is very rare. There is no standardized approach to the clinical identification of primary thyroid lymphoma (PTL), making early diagnosis difficult. A multidisciplinary approach and close follow-up are needed. The mechanisms of the link between DS and PTL are poorly understood and remain to be elucidated.