AURKB promotes bladder cancer progression by deregulating the p53 DNA damage response pathway via MAD2L2.

BACKGROUND: Bladder cancer (BC) is the most common urinary tract malignancy. Aurora kinase B (AURKB), a component of the chromosomal passenger protein complex, affects chromosomal segregation during cell division. Mitotic arrest-deficient 2-like protein 2 (MAD2L2) interacts with various proteins and contributes to genomic integrity. Both AURKB and MAD2L2 are overexpressed in various human cancers and have synergistic oncogenic effects; therefore, they are regarded as emerging therapeutic targets for cancer. However, the relationship between these factors and the mechanisms underlying their oncogenic activity in BC remains largely unknown. The present study aimed to explore the interactions between AURKB and MAD2L2 and how they affect BC progression via the DNA damage response (DDR) pathway. METHODS: Bioinformatics was used to analyze the expression, prognostic value, and pro-tumoral function of AURKB in patients with BC. CCK-8 assay, colony-forming assay, flow cytometry, SA-ß-gal staining, wound healing assay, and transwell chamber experiments were performed to test the viability, cell cycle progression, senescence, and migration and invasion abilities of BC cells in vitro. A nude mouse xenograft assay was performed to test the tumorigenesis ability of BC cells in vivo. The expression and interaction of proteins and the occurrence of the senescence-associated secretory phenotype were detected using western blot analysis, co-immunoprecipitation assay, and RT-qPCR. RESULTS: AURKB was highly expressed and associated with prognosis in patients with BC. AURKB expression was positively correlated with MAD2L2 expression. We confirmed that AURKB interacts with, and modulates the expression of, MAD2L2 in BC cells. AURKB knockdown suppressed the proliferation, migration, and invasion abilities of, and cell cycle progression in, BC cells, inducing senescence in these cells. The effects of AURKB knockdown were rescued by MAD2L2 overexpression in vitro and in vivo. The effects of MAD2L2 knockdown were similar to those of AURKB knockdown. Furthermore, p53 ablation rescued the MAD2L2 knockdown-induced suppression of BC cell proliferation and cell cycle arrest and senescence in BC cells. CONCLUSIONS: AURKB activates MAD2L2 expression to downregulate the p53 DDR pathway, thereby promoting BC progression. Thus, AURKB may serve as a potential molecular marker and a novel anticancer therapeutic target for BC.

MTHFD2 promotes PD-L1 expression via activation of the JAK/STAT signalling pathway in bladder cancer.

Although combination chemotherapy is widely used for bladder cancer (BC) treatment, the recurrence and progression rates remain high. Therefore, novel therapeutic targets are required. Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) contributes to tumourigenesis and immune evasion in several cancers; however, its biological function in BC remains unknown. This study aimed to investigate the expression, prognostic value and protumoural function of MTHFD2 in BC and elucidate the mechanism of programmed death-ligand 1 (PD-L1) upregulation by MTHFD2. An analysis using publicly available databases revealed that a high MTHFD2 expression was correlated with clinical features and a poor prognosis in BC. Furthermore, MTHFD2 promoted the growth, migration, invasion and tumourigenicity and decreased the apoptosis of BC cells in vivo and in vitro. The results obtained from databases showed that MTHFD2 expression was correlated with immune infiltration levels, PD-L1 expression, and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. The expression of MTHFD2, PD-L1 and JAK/STAT signalling pathway-related proteins increased after interferon gamma treatment and decreased after MTHFD2 knockdown. Moreover, addition of a JAK/STAT pathway activator partially reduced the effect of MTHFD2 knockdown on BC cells. Collectively, our findings suggest that MTHFD2 promotes the expression of PD-L1 through the JAK/STAT signalling pathway in BC.

SQLE Knockdown inhibits bladder cancer progression by regulating the PTEN/AKT/GSK3ß signaling pathway through P53.

Bladder cancer (BCa) is one of the most common malignancies worldwide. However, the lack of accurate and effective targeted drugs has become a major problem in current clinical treatment of BCa. Studies have demonstrated that squalene epoxidase (SQLE), as a key rate-limiting enzyme in cholesterol biosynthesis, is involved in cancer development. In this study, our analysis of The Cancer Genome Atlas, The Genotype-Tissue Expression, and Gene Expression Omnibus databases showed that SQLE expression was significantly higher in cancer tissues than it was in adjacent normal tissues, and BCa tissues with a high SQLE expression displayed a poor prognosis. We then confirmed this result in qRT-PCR and immunohistochemical staining experiments, and our vitro studies demonstrated that SQLE knockdown inhibited tumor cell proliferation and metastasis through the PTEN/AKT/GSK3ß signaling pathway. By means of rescue experiments, we proved that that P53 is a key molecule in SQLE-mediated regulation of the PTEN/AKT/GSK3ß signaling pathway. Simultaneously, we verified the above findings through a tumorigenesis experiment in nude mice. In conclusion, our study shows that SQLE promotes BCa growth through the P53/PTEN/AKT/GSK3ß axis, which may serve as a therapeutic biological target for BCa.

STAT6 promoting oxalate crystal deposition-induced renal fibrosis by mediating macrophage-to-myofibroblast transition via inhibiting fatty acid oxidation.

OBJECTIVE AND DESIGN: Kidney stones commonly occur with a 50% recurrence rate within 5 years, and can elevate the risk of chronic kidney disease. Macrophage-to-myofibroblast transition (MMT) is a newly discovered mechanism that leads to progressive fibrosis in different forms of kidney disease. In this study, we aimed to investigate the role of MMT in renal fibrosis in glyoxylate-induced kidney stone mice and the mechanism by which signal transducer and activator of transcription 6 (STAT6) regulates MMT. METHODS: We collected non-functioning kidneys from patients with stones, established glyoxylate-induced calcium oxalate stone mice model and treated AS1517499 every other day in the treatment group, and constructed a STAT6-knockout RAW264.7 cell line. We first screened the enrichment pathway of the model by transcriptome sequencing; detected renal injury and fibrosis by hematoxylin eosin staining, Von Kossa staining and Sirius red staining; detected MMT levels by multiplexed immunofluorescence and flow cytometry; and verified the binding site of STAT6 at the PPARα promoter by chromatin immunoprecipitation. Fatty acid oxidation (FAO) and fibrosis-related genes were detected by western blot and real-time quantitative polymerase chain reaction. RESULTS: In this study, we found that FAO was downregulated, macrophages converted to myofibroblasts, and STAT6 expression was elevated in stone patients and glyoxylate-induced kidney stone mice. The promotion of FAO in macrophages attenuated MMT and upregulated fibrosis-related genes induced by calcium oxalate treatment. Further, inhibition of peroxisome proliferator-activated receptor-α (PPARα) eliminated the effect of STAT6 deletion on FAO and fibrosis-associated protein expression. Pharmacological inhibition of STAT6 also prevented the development of renal injury, lipid accumulation, MMT, and renal fibrosis. Mechanistically, STAT6 transcriptionally represses PPARα and FAO through cis-inducible elements located in the promoter region of the gene, thereby promoting MMT and renal fibrosis. CONCLUSIONS: These findings establish a role for STAT6 in kidney stone injury-induced renal fibrosis, and suggest that STAT6 may be a therapeutic target for progressive renal fibrosis in patients with nephrolithiasis.

Exogenously applied sodium nitroprusside alleviates nickel toxicity in maize by regulating antioxidant activities and defense-related gene expression.

Nickel (Ni) stress adversely affects plant growth and biomass accumulation, posturing severe menace to crop production and food security. The current study aimed to determine the putative role of sodium nitroprusside (SNP) in mitigating Ni-induced phytotoxicity and identify the underlying defense mechanisms in maize, which are poorly understood. Our findings showed that SNP significantly augmented plant growth, biomass, and photosynthesis-related attributes (Fv/Fm, Fm, qP ETR, and ΦPSII) through diminishing Ni uptake and translocation in root and shoot tissues of maize under Ni stress conditions. In parallel, exogenous SNP substantially relieved maize seedlings from Ni-induced stress by enhancing enzymatic (SOD, CAT, and GPX) and non-enzymatic (phenol and flavonoids) antioxidant defenses and reducing oxidative stress indicators (MDA and H2 O2 ). The results revealed that SNP treatment increased the content of organic osmolyte glycine betaine and the activity of GST, concomitantly with ATP and ionic exchange capacity (including Ca2+ -ATPase and Mg2+ -ATPase), advocating its sufficiency to promote plant growth and avert Ni-induced stress in maize plants. The only exception was the production of organic acids (citric, oxalic, malic, and formic acids), which was reduced as SNP treatment relieved maize seedlings from Ni-induced oxidative damage. The application of SNP also displayed higher expression of defense- and detoxifying-related genes than in control treatments. Together, our data highlighted the mechanism involved in the amelioration of Ni toxicity by SNP; thus, suggesting a potential role of SNP in mitigating the adverse effects of Ni-contaminated soils to boost growth and yield of crop plants, that is, maize.

Uptake, accumulation, toxicity, and interaction of metallic-based nanoparticles with plants: current challenges and future perspectives.

The rapid development of industrialization is causing several fundamental problems in plants due to the interaction between plants and soil contaminated with metallic nanoparticles (NPs). Numerous investigations have been conducted to address the severe toxic effects caused by nanoparticles in the past few decades. Based on the composition, size, concentration, physical and chemical characteristics of metallic NPs, and plant types, it enhances or lessens the plant growth at various developmental stages. Metallic NPs are uptaken by plant roots and translocated toward shoots via vascular system based on composition, size, shape as well as plant anatomy and cause austere phytotoxicity. Herein, we tried to summarize the toxicity induced by the uptake and accumulation of NPs in plants and also we explored the detoxification mechanism of metallic NPs adopted by plants via using different phytohormones, signaling molecules, and phytochelatins. This study was intended to be an unambiguous assessment including current knowledge on NPs uptake, accumulation, and translocation in higher plants. Furthermore, it will also provide sufficient knowledge to the scientific community to understand the metallic NPs-induced inhibitory effects and mechanisms involved within plants.

microRNA-21-5p from M2 macrophage-derived extracellular vesicles promotes the differentiation and activity of pancreatic cancer stem cells by mediating KLF3.

AIM: Given the fact that tumor-associated macrophage-derived extracellular vesicles (EVs) are attributable to tumor aggressiveness, this research intends to decode the mechanism of M2 macrophage-derived EVs in the differentiation and activities of pancreatic cancer (PaCa) stem cells via delivering microRNA (miR)-21-5p. METHODS: Polarized M2 macrophages were induced, from which EVs were collected and identified. miR-21-5p expression in M2 macrophage-derived EVs was tested. After cell sorting, CD24+CD44+EpCAM+ stem cells were co-cultured with M2 macrophages, in which miR-21-5p was upregulated or downregulated. The effects of M2 macrophage-derived EVs and miR-21-5p on Nanog/octamer-binding transcription factor 4 (Oct4) expression, sphere formation, colony formation, invasion and migration capacities, apoptosis, and in vivo tumorigenic ability were examined. Krüppel-like factor 3 (KLF3) expression and its interaction with miR-21-5p were determined. RESULTS: M2 macrophage-derived EVs promoted PaCa stem cell differentiation and activities. miR-21a-5p was upregulated in M2 macrophage-derived EVs. miR-21a-5p downregulation in M2 macrophage-derived EVs inhibited Nanog/Oct4 expression and impaired sphere-forming, colony-forming, invasion, migration, and anti-apoptosis abilities of PaCa stem cells in vitro and tumorigenic ability in vivo. miR-21-5p targeted KLF3 to mediate the differentiation and activities of PaCa stem cells, and KLF3 was downregulated in PaCa stem cells. CONCLUSION: This work explains that M2 macrophage-derived exosomal miR-21a-5p stimulates differentiation and activity of PaCa stem cells via targeting KLF3, paving a novel way for attenuating PaCa stemness.

Geniposide protection against Aß1-42 toxicity correlates with mTOR inhibition and enhancement of autophagy.

Overactivation of the PI3-K/Akt/mTOR signaling pathway and inhibition of autophagy in the brain are involved in Alzheimer's disease. The present paper's goal was to explore the potential mechanisms of geniposide to protect against Alzheimer's disease. We treated the human neuroblastoma SH-SY5Y cell line with Aß1-42 as an Alzheimer's disease in vitro model to explore the potential mechanisms of geniposide to protect against Alzheimer's disease. Further, SH-SY5Y cells damaged by Aß1-42 were treated with geniposide. Akt/mTOR-related proteins and autophagy-associated proteins were measured to reveal the molecular mechanisms by which geniposide protects against Aß1-42-induced toxicity. Results showed that Akt and mTOR's geniposide inhibited phosphorylation induced by Aß1-42, enhanced expression of the LC3II/LC3I ratio, and Atg7 and Beclin1 expression and inhibited expression of p62 induced by Aß1-42. Our results lead us to hypothesize that inhibition of the Akt/mTOR signaling pathway and autophagy enhancement are fundamental molecular mechanisms for geniposide to protect against Aß toxicity.

Investigation of the Physiological, Biochemical and Antifungal Susceptibility Properties of Candida auris.

BACKGROUND: Candida auris is an emerging pathogen associated with outbreaks in clinical settings. Isolates of the pathogen have been geographically clustered into four clades with high intra-clade clonality. Pathogenicity varies among the clades, highlighting the importance of understanding these differences. OBJECTIVES: To examine the physiological and biochemical properties of each clade of C. auris to improve our understanding of the fungus. METHODS: Optimal growth temperatures of four strains from three clades, East Asia, South Asia and South Africa, were explored. Moreover, assimilation and antifungal susceptibility properties of 22 C. auris strains from the three clades were studied. RESULTS: The optimal growth temperatures of all strains were 35-37 °C. Assimilation testing demonstrated that the commercial API ID 32 C system can be used to reliably identify C. auris based on the biochemical properties of the yeast. Notably, C. auris can be uniquely differentiated from commonly clinical fungi by its ability to assimilate raffinose and inability to utilize D-xylose, suggesting a useful simple screening tool. The antifungal susceptibility results revealed that all strains are resistant against fluconazole (minimal inhibitory concentration (MIC) 4 to > 64 µg/mL) and miconazole (MIC 8 to > 16 µg/mL), with strains from the Japanese lineage showing relatively lower MIC values (1-4 µg/mL). Conversely, itraconazole, voriconazole, amphotericin B, micafungin and caspofungin were active against most of the tested strains. On the clade level, East Asian strains generally showed lower MICs against azoles comparing to the other clades, while they displayed MICs against flucytosine higher than those of strains from South Africa and South Asia clades. CONCLUSION: Our data suggest a simple identification approach of C. auris based on its physiological and biochemical properties and highlight aspects of C. auris population from various clades.

Positive association of serum uric acid with new-onset diabetes in Chinese women with hypertension in a retrospective analysis of the China Stroke Primary Prevention Trial.

AIMS: To investigate the association of baseline serum uric acid (UA) with new-onset diabetes, and to explore the possible effect modifiers in Chinese adults with hypertension. MATERIALS AND METHODS: A total of 14 943 hypertensive patients with available UA measurements and without diabetes at baseline were included from the China Stroke Primary Prevention Trial (CSPPT). Participants were randomly assigned to a double-blind daily treatment with 10 mg enalapril and 0.8 mg folic acid or 10 mg enalapril alone. The primary outcome was new-onset diabetes, defined as physician-diagnosed diabetes or use of glucose-lowering drugs during follow-up, or fasting glucose ≥7.0 mmol/L at the exit visit. RESULTS: Over a median follow-up of 4.5 years, 1623 participants (10.9%) developed diabetes. Overall, there was a positive association between baseline UA and new-onset diabetes in women (per SD increment; adjusted odds ratio [OR] 1.14, 95% confidence interval [CI] 1.07, 1.23), but not in men (adjusted OR 1.01, 95% CI 0.92, 1.10). Moreover, a stronger positive association between baseline UA and new-onset diabetes was found among women with lower time-averaged on-treatment systolic blood pressure during the treatment period (<140 vs. ≥140 mmHg; P-interaction = 0.024), higher baseline body mass index (<24 vs. ≥24 kg/m2 ; P-interaction = 0.012), or higher baseline waist circumference (<80 vs. ≥80 cm; P-interaction = 0.032). CONCLUSIONS: Our study suggested that higher baseline UA was significantly associated with increased risk of new-onset diabetes in hypertensive Chinese women, but not in men. Further prospective studies are required to validate the differential association by sex.

Ascorbate inducible N259 glycans on prolyl 4-hydroxylase subunit α1 promote hydroxylation and secretion of type I collagen.

Ascorbic acid (vitamin C, VC) increases the secretion of mature collagen by promoting the activity of prolyl 4-hydroxylase subunit α 1 (P4HA1). To explore the mechanism involved, we investigated the role of N-linked glycosylation, which can regulate enzyme activity. P4HA1 has two glycosylation sites, Asn (N) 113 and N259. Our studies show that glycosylation of N259, but not N113, by STT3B and magnesium transporter 1 (MAGT1) is augmented by VC. N259 glycosylation on P4HA1 correlates with enhanced pepsin-resistant collagen 1α2 secretion. Downregulation of Stt3b and Magt1 reduces N259 glycans on P4HA1. In collagen 1α2 purified from Stt3b-silenced fibroblasts, decreased hydroxylation is found at five specific proline residues, while significantly increased hydroxylation is noted at two proline residues. Similarly, in collagen 1α1, reduced proline hydroxylation is detected at eight sites and increased proline hydroxylation is found at four sites. These results suggest that N-linked glycosylation of P4HA1 can direct hydroxylation at specific proline residues and affect collagen maturation.

Spermidine Enhances Heat Tolerance of Rice Seeds by Modulating Endogenous Starch and Polyamine Metabolism.

Polyamines have been reported to be involved in grain filling and they might contribute to the construction of heat resistance of some cereals. In this study, the hybrid rice 'YLY 689' was used to explore the possible effects of exogenous spermidine (Spd) on seed quality under high temperature during the filling stage. Rice spikes were treated with Spd or its synthesis inhibitor cyclohexylamine (CHA) after pollination, and then the rice plants were transferred to 40 °C for 5-day heat treatment. The results showed that, compared with the control under high temperature, Spd pretreatment significantly improved the germination percentage, germination index, vigor index, seedling shoot height, and dry weight of seeds harvested at 35 days after pollination, while the CHA significantly decreased the seed germination and seedling growth. Meanwhile, Spd significantly increased the peroxidase (POD) activity and decreased the malondialdehyde (MDA) content in seeds. In addition, after spraying with Spd, the endogenous content of spermidine and spermine and the expression of their synthetic genes, spermidine synthase (SPDSYN) and spermine synthase (SPMS1 and SPMS2), significantly increased, whereas the accumulation of amylose and total starch and the expression of their related synthase genes, soluble starch synthase II-3 (SS II-3) and granules bound starch synthase I (GBSSI), also increased to some extent. The data suggests that exogenous Spd pretreatment could alleviate the negative impacts of high temperature stress on rice seed grain filling and improve the rice seed quality to some extent, which might be partly caused by up-regulating endogenous polyamines and starch metabolism.

The Application of Ferric Chloride-Lignin Sulfonate as Shale Inhibitor in Water-Based Drilling Fluid.

A series of ferric chloride-lignin sulfonate (FCLS) was prepared from ferric chloride and lignin sulfonate to be used as shale inhibitor. The swelling rate of clay with FCLS-2 (w/w = 0.3%) decreased to 41.9%. Compared with control, FCLS-2 displayed high inhibitive ability against the hydrating and swelling processes of clay. Thus, the swelling degree of samples with FCLS-2 was much lower than that of the control, as well as the mud ball was more stable in FCLS-2 solution. Essentially, these excellent performances in inhibitor were assigned to the hydrogen bonding, electrostatic interaction and anchoring between FCLS-2 and other components. In addition, FCLS-2 has good compatibility with other common drilling fluid additives, and it can reduce the viscosity of systems, regardless of the room temperature or high temperature.

Studies on optimum harvest time for hybrid rice seed.

BACKGROUND: Timely harvest is critical for hybrid rice to achieve maximum seed viability, vigor and yield. However, how to predict the optimum harvest time has been rarely reported so far. RESULTS: The seed vigor of Zhuliangyou 06 (ZLY06) increased and reached the highest level at 20 days after pollination (DAP), when seed moisture content had a lower value, which was maintained until final seed maturation. For Chunyou 84 (CY84), seed vigor, fresh and dry weight had relatively high values at 25 DAP, when seed moisture content reached the lowest value and changed slightly from 25 to 55 DAP. In both hybrid rice varieties, seed glume chlorophyll content declined rapidly from 10 to 30 DAP and remained at a very low level after 35 DAP. Starch content exhibited an increasing trend during seed maturation, while both soluble sugar content and amylase activity decreased significantly at the early stages of seed development. Moreover, correlation analyses showed that seed dry weight, starch content and superoxide dismutase activity were significantly positively correlated with seed vigor. In contrast, chlorophyll content, moisture content, soluble sugar, soluble protein, abscisic acid, gibberellin content, electrical conductivity, catalase and ascorbate peroxidase activities were significantly negatively correlated with seed vigor. Physiological and biochemical parameters were obviously more closely related with seed vigor than with seed germinability during seed development. CONCLUSION: Seed vigor could be better used as a comprehensive factor to predict the optimum seed harvest time. It is suggested that for ZLY06 seeds could be harvested as early as 20 DAP, whereas for CY84 the earliest optimum harvest time was 25 DAP. © 2016 Society of Chemical Industry.

Comparative proteomic analysis reveals alterations in development and photosynthesis-related proteins in diploid and triploid rice.

BACKGROUND: Polyploidy has pivotal influences on rice (Oryza sativa L.) morphology and physiology, and is very important for understanding rice domestication and improving agricultural traits. Diploid (DP) and triploid (TP) rice shows differences in morphological parameters, such as plant height, leaf length, leaf width and the physiological index of chlorophyll content. However, the underlying mechanisms determining these morphological differences are remain to be defined. To better understand the proteomic changes between DP and TP, tandem mass tags (TMT) mass spectrometry (MS)/MS was used to detect the significant changes to protein expression between DP and TP. RESULTS: Results indicated that both photosynthesis and metabolic pathways were highly significantly associated with proteomic alteration between DP and TP based on biological process and pathway enrichment analysis, and 13 higher abundance chloroplast proteins involving in these two pathways were identified in TP. Quantitative real-time PCR analysis demonstrated that 5 of the 13 chloroplast proteins ATPF, PSAA, PSAB, PSBB and RBL in TP were higher abundance compared with those in DP. CONCLUSIONS: This study integrates morphology, physiology and proteomic profiling alteration of DP and TP to address their underlying different molecular mechanisms. Our finding revealed that ATPF, PSAA, PSAB, PSBB and RBL can induce considerable expression changes in TP and may affect the development and growth of rice through photosynthesis and metabolic pathways.

Physiological changes and sHSPs genes relative transcription in relation to the acquisition of seed germination during maturation of hybrid rice seed.

BACKGROUND: During the production of early hybrid rice seed, the seeds dehydrated slowly and retained high moisture levels when rainy weather lasted for a couple of days, and the rice seeds easily occurred pre-harvest sprouting (PHS) along with high temperature. Therefore it is necessary to harvest the seeds before the PHS occurred. RESULTS: The seeds of hybrid rice (Oryza sativa L. subsp. indica) cv. Qianyou No1 that harvests from 19 to 28 days after pollination (DAP) all had high seed vigour. The seed moisture content at 10 DAP was 36.1%, and declined to 28.6% at 19 DAP; the contents of soluble sugar and total starch increased significantly with the development of seeds. The soluble protein content, the level of abscisic acid (ABA) and gibberellin (GA3 ), and ascorbate peroxidase (APX) activity continued to decrease from 10 DAP to 19 DAP. The seeds at 19 DAP had the highest peroxidase (POD) activity and lowest catalase (CAT) activity while the superoxide dismutase (SOD) activity had no significant difference among the different developing periods. The relative expressions of genes 64S Hsp18.0 and Os03g0267200 transcripts increased significantly from 10 to 19 DAP, and then decreased. However, no significant change was recorded in soluble protein, sugar and GA3 after 16 DAP, and they all significantly correlated with seed viability and vigour during the process of seed maturity. CONCLUSION: The seeds of hybrid rice Qianyou No1 had a higher viability and vigour when harvested from 19 DAP to 28 DAP, the transcription levels of 64S Hsp18.0 and Os03g0267200 increased significantly from 10 DAP to 19 DAP and the highest value was recorded at 19 DAP. The seeds could be harvested as early as 19 DAP without negative influence on seed vigour and viability.

N-Heterocyclic Carbene Catalyzed γ-Dihalomethylenation of Enals by Single-Electron Transfer.

An N-heterocyclic carbene (NHC) catalyzed dihalomethylenation of enals is described. It is a rare example of merging NHC catalysis with single-electron chemistry, a challenging topic with limited previous success. The versatile carbon-centered trihalomethyl radicals have been demonstrated, for the first time, to be compatible with an NHC-bound intermediate, thus leading to efficient and regioselective intermolecular C-C bond formation. The mild process provides straightforward access to unsaturated δ,δ-dihalo esters.

[Advances of NIR spectroscopy technology applied in seed quality detection].

Near infrared spectroscopy (NIRS) technology developed fast in recent years, due to its rapid speed, less pollution, high-efficiency and other advantages. It has been widely used in many fields such as food, chemical industry, pharmacy, agriculture and so on. The seed is the most basic and important agricultural capital goods, and seed quality is important for agricultural production. Most methods presently used for seed quality detecting were destructive, slow and needed pretreatment, therefore, developing one kind of method that is simple and rapid has great significance for seed quality testing. This article reviewed the application and trends of NIRS technology in testing of seed constituents, vigor, disease and insect pests etc. For moisture, starch, protein, fatty acid and carotene content, the model identification rates were high as their relative contents were high; for trace organic, the identification rates were low as their relative content were low. The heat-damaged seeds with low vigor were discriminated by NIRS, the seeds stored for different time could also been identified. The discrimination of frost-damaged seeds was impossible. The NIRS could be used to identify health and infected disease seeds, and did the classification for the health degree; it could identify parts of the fungal pathogens. The NIRS could identify worm-eaten and health seeds, and further distinguished the insect species, however the identification effects for small larval and low injury level of insect pests was not good enough. Finally, in present paper existing problems and development trends for NIRS in seed quality detection was discussed, especially the single seed detecting technology which was characteristic of the seed industry, the standardization of its spectral acquisition accessories will greatly improve its applicability.

N-heterocyclic carbene catalyzed enantioselective α-fluorination of aliphatic aldehydes and α-chloro aldehydes: synthesis of α-fluoro esters, amides, and thioesters.

The asymmetric fluorination of azolium enolates that are generated from readily available simple aliphatic aldehydes or α-chloro aldehydes and N-heterocyclic carbenes (NHCs) is described. The process significantly expands the synthetic utility of NHC-catalyzed fluorination and provides facile access to a wide range of α-fluoro esters, amides, and thioesters with excellent enantioselectivity. Pyrazole was identified as an excellent acyl transfer reagent for catalytic amide formation.

Purine metabolite inosine induced by transforming growth factor­ß promotes epithelial­mesenchymal transition in colorectal cancer.

Transforming growth factor-ß (TGF-ß) signaling pathway serves a pivotal role in the pathogenesis of colorectal cancer (CRC). However, the specific molecular mechanisms by which the TGF-ß signaling pathway regulates CRC are still not fully understood. In the present study, metabolomics and transcriptomics were used to screen for key metabolites and regulatory genes most related to the regulation of the TGF-ß signaling pathway in CRC. Additionally, reverse transcription-quantitative PCR, western blotting and Transwell assays were performed to assess the process of epithelial-mesenchymal transition (EMT). Metabolomics analysis indicated that TGF-ß1 has an impact on purine metabolism, leading to an increase in the purine metabolite inosine. The increase of inosine is essential for facilitating EMT and cell migration in CRC cells. Furthermore, the integrated analysis of metabolomics and transcriptomics data revealed that TGF-ß1 induces the expression of laccase domain-containing 1 (LACC1), an enzyme involved in the regulation of inosine. Knockdown of LACC1 resulted in a reduction of TGF-ß1-induced alterations in inosine levels, EMT and cell migration in CRC cells. The results of the present study suggest that the TGF-ß signaling pathway is involved in the regulation of purine metabolism in CRC through the modulation of LACC1 expression. Furthermore, LACC1 appears to influence EMT and cell migration by elevating the levels of the purine metabolite inosine.