Copper-Catalyzed Coupling of Amines with Carbazates: An Approach to Carbamates.

A new approach for the preparation of carbamates via the copper-catalyzed cross-coupling reaction of amines with alkoxycarbonyl radicals generated from carbazates is described. This environmentally friendly protocol takes place under mild conditions and is compatible with a wide range of amines, including aromatic/aliphatic and primary/secondary substrates.

Hydrogen Sulfide Alleviates Lipopolysaccharide-Induced Diaphragm Dysfunction in Rats by Reducing Apoptosis and Inflammation through ROS/MAPK and TLR4/NF-κB Signaling Pathways.

Diaphragm dysfunction is an important clinical problem worldwide. Hydrogen sulfide (H2S) is involved in many physiological and pathological processes in mammals. However, the effect and mechanism of H2S in diaphragm dysfunction have not been fully elucidated. In this study, we detected that the level of H2S was decreased in lipopolysaccharide- (LPS-) treated L6 cells. Treatment with H2S increased the proliferation and viability of LPS-treated L6 cells. We found that H2S decreased reactive oxygen species- (ROS-) induced apoptosis through the mitogen-activated protein kinase (MAPK) signaling pathway in LPS-treated L6 cells. Administration of H2S alleviated LPS-induced inflammation by mediating the toll-like receptor-4 (TLR-4)/nuclear factor-kappa B (NF-κB) signaling pathway in L6 cells. Furthermore, H2S improved diaphragmatic function and structure through the reduction of inflammation and apoptosis in the diaphragm of septic rats. In conclusion, these findings indicate that H2S ameliorates LPS-induced diaphragm dysfunction in rats by reducing apoptosis and inflammation through ROS/MAPK and TLR4/NF-κB signaling pathways. Novel slow-releasing H2S donors can be designed and applied for the treatment of diaphragm dysfunction.

Copper-Catalyzed TBHP-Mediated Radical Cross-Coupling Reaction of Sulfonylhydrazides with Thiols Leading to Thiosulfonates.

A tert-butyl hydroperoxide (TBHP)-mediated coupling of sulfonylhydrazides with thiols catalyzed by CuBr2 to afford thiosulfonates via a radical process is described.

Downregulation of leptin inhibits growth and induces apoptosis of lung cancer cells via the Notch and JAK/STAT3 signaling pathways.

Previous studies have documented that leptin is involved in the pathogenesis of many human cancer types by regulation of numerous signal transduction pathways. The aim of this study was to investigate the biological roles of leptin and the mechanisms attributed to its action in non-small cell lung cancer (NSCLC) cell lines. The expression of leptin was measured by quantitative real-time PCR and western blot in seven NSCLC cell lines. Proliferation and apoptosis of NSCLC cells in response to leptin knockdown were determined by MTT assay and flow cytometry, respectively. The effect of leptin knockdown on the Notch and JAK/STAT3 signaling pathways was further examined by western blot. Leptin expression was significantly increased in NSCLC cell lines compared with normal human bronchial epithelial cell HBE. Leptin knockdown inhibited cell proliferation and induced apoptosis in NSCLC cell lines through inactivation of the Notch and JAK/STAT3 signaling pathways. Furthermore, gene silencing of Notch signaling with Notch-1 siRNA or inhibition of JAK/STAT3 signaling by JSI-124, an inhibitor of STAT3, resulted in proliferation inhibition and apoptosis induction in NSCLC A549 cells. Our findings suggested that leptin knockdown could become a new approach for the prevention of lung cancer progression, which is likely to be mediated at least partially by inactivation of the Notch and JAK/STAT3 signaling pathways.

[Study on Outliers Influence in NIR Quantitative Analysis Model].

As a secondary analysis method, reproducibility and reliability of near-infrared spectroscopy (NIRS) quantitative analysis are quite dependent on modelling process. In this paper, it is focused on outlier analysis for protein quantitative model of wheat based on NIRS. The purpose is to discuss the outlier effect in modelling process of complex sample set. The indicator of outliers is the deviation between two interpretative percentage curves in partial least squares regression (PLSR) modelling, when two percentage curves have significant deviation or departure point, the sample set should include the outliers. The innovative research work is the analysis and treatment of outliers. On the basis of sub-model ergodic calculation method, outliers can be gradually identified and picked-up. The standard deviation of model's prediction residual is used as the reference graduation to distinguish the degree of deviation. According to the degree of deviation from sample population, outliers can also be divided into significant outliers, relative outliers and potential outliers. In this paper, the significant outliers of the sample set are about 7.8%, and the relative outliers are about 15.6%. The outliers will pull normal samples apart from the ideal fitting line and make the dispersity increase. No matter modelling with removed outliers or weighted samples, the purpose is to make the fitting results of quantitative analysis modelling more inclined to majority samples, while reducing or eliminating the impact of outliers.

[VMTBB-Based Spectral Radiometric Calibration of NIR Fiber Coupled Spectrometer].

The medium temperature black body (MTBB) is conventional high precision equipment used as spectral radiometric scale in infrared spectral region. However, in near-infrared (NIR) spectral region, there are few papers about spectral radiometric calibration by using MTBB, that is because NIR spectral region is the borderland of its effective spectral region. The main research of this paper is spectral radiometric calibration method by using MTBB in NIR spectral region. Accordingly, this paper is devoted mostly to a discussion of how the calibration precision could be affected by selecting different structural parameters of calibration model. The purpose of this paper is to present the results of research and provide technical reference for improving the traceability in NIR spectral radiometric calibration. In this paper, a NIR fiber coupled spectrometer, whose wavelength range covers from 950 to 1700 nm, has been calibrated by a MTBB with adjustable temperature range from 50 to 1050 °C. Concentrating on calibration process, two key points have been discussed. For one thing, the geometric factors of radiation transfer model of the calibration systems have been compared between traditional structure and fiber direct-coupled structure. Because the fiber direct-coupled model is simple and effective, it has been selected instead of traditional model based on the radiation transfer between two coaxial discs. So, it is an advantaged radiation transfer model for radiometric calibration of fiber coupled spectrometer. For another thing, the relation between calibration accuracy and structural parameters of calibration model has been analyzed intensively. The root cause is scale feature of attribute of calibration data itself, which is the nonlinear structure in scales of spectral data. So, the high precision calibration needs nonlinear calibration model, and the uniform sampling for scale feature is also very important. Selecting sample is an inevitable problem when the nonlinear model is explained by small sample dataset. As the analytic results, there are obviously influences for the calibration precision among different strategies of selecting model's structural parameters. The calibration precision, which is mathematical described by standard deviation of spectral data for calibration, could be from ±0.1% to ±1%.

CoPc-catalyzed selective radical arylation of anilines with arylhydrazines for synthesis of 2-aminobiaryls.

CoPc-catalyzed selective radical arylation of anilines with arylhydrazines to afford 2-aminobiaryls in moderate to good yields is described.

[Geochemical character of precipitation in summer of Shanghai 2008-2009].

The chemical compositions of the rainwater collected in Shanghai in Summer of 2008-2009 were investigated. The chemical character and pollutant source of rainwater were evaluated depended on HYSPLIT model, ions tracer techniques, correlation and principal component analysis. The results showed that: (1) the mean pH in rain was 4.72 and 4.68; (2) the frequency of acid rain was 53.30% and 63.30%, respectively, in 2008 and 2009; (3) ionic concentration was SO4(2-) > NH4+ > NO3- > Cl- > Ca2+ > Na+ > Mg2+ > K+, in which the secondary components like SO4(2-), NO3- and NH4+ contributed significantly to total ions of rainwater and they accounted for 55.01% and 65.97% of total ions in 2008 and 2009, respectively, which indicate the severe secondary pollution in Shanghai; (4) the ratio of SO4(2-) to NO3- in Summer precipitation in 2008 and 2009 was 3.19 and 2.13, respectively, which implies sulfuric-nitrous mixed type of precipitation; (5) the content of DOC varied from 1.36 mg/L to 10.69 mg/L and average value was 2.44 mg/L in rainwater; (6) SO4(2-) and NO3- were mainly in the form of (NH4) 2SO4 and NH4NO3, which showed the dominant neutralization effect of NH4+ over Ca2+ in Summer. Source identification indicated that SO4(2-), NH4+, NO3-, K+ and most Ca2+ derived from anthropogenic sources, while Mg2+ and Cl- derived from both marine and non-marine but non-marine was over marine. The chemistry of precipitation in Shanghai was impacted by local pollutants and the long-and moderate-range transport by Southwest monsoon according to backward trajectory analysis.

BoPMEI1, a pollen-specific pectin methylesterase inhibitor, has an essential role in pollen tube growth.

Pectin methylesterase (PME) is known to have important roles in pollen development and pollen tube growth. As pivotal regulatory factors in PME activity modulation, PME inhibitors (PMEIs) are thought to be key regulators of cell wall stability at the tip of the pollen tube. We report on the cloning and characterization of a novel B. oleracea PMEI gene, BoPMEI1. Heterologously expressed BoPMEI1 showed PMEI activity. RT-PCR studies of different tissues and promoter-GUS fusions confirmed that BoPMEI1 was specifically expressed in mature pollen grains and pollen tubes. Based on in vivo transient assays, we found that BoPMEI1 appears to be largely localized to the plasma membrane. Transgenic Arabidopsis plants expressing antisense BoPMEI1 under the control of the CaMV 35S promoter suppressed the expression of the orthologous gene At1g10770, which led to partial male sterility and decreased seed set by inhibition of pollen tube growth. Our study demonstrates the involvement of BoPMEI1 in pollen tube growth.

Cloning and expression analysis of a pollen preferential rapid alkalinization factor gene, BoRALF1, from broccoli flowers.

Rapid alkalinization factors (RALFs) are recently reported active peptide hormones and are considered to play important roles in plant development. We previously identified a differentially expressed cDNA fragment between cabbage flower buds of sterility lines and its maintainer line, which showed significant homology to Arabidopsis RALFL9. The novel RALF cDNA (BoRALF1) was isolated from broccoli flower buds by EST assembly. The open reading frame (ORF) comprises 240 bp, encoding a small putative preprotein of 79 amino acids (molecular weight of 8.72 kDa and a pI of 7.8), which contains the mature polypeptide at its C terminus. BoRALF1 shares 70.3% identity with Arabidopsis RALFL9, but has only moderate similarity with functionally characterized RALFs (ranging from 16.2% to 38.0%). BoRALF1 shows typical features of RALFs, including the 28-aa signal peptide, typical arrangement of four position conserved cysteines, the YIXY motif and a similar secondary structure. RT-PCR studies of different tissues and promoter-GUS fusions confirmed that BoRALF1 is expressed strictly in mature pollen grains and in the anther cells around the loculi. Based on in vivo transient assays, we found that BoRALF1 appears to be largely localized in the plasma membrane. Although the function of BoRALF1 remains to be determined, our experiments confirm the presence of RALF peptide in broccoli, and suggest it could have a role in anther or pollen development.

[Gene cloning and expression analysis of a male sterility related gene BoDHAR from broccoli].

A differentially expressed cDNA fragment obtained from a cDNA-AFLP analysis, which performed on floral buds of male sterile and fertile lines of cabbage, was used as a querying probe to blast the Genbank and Arabidopsis databases. Based on the assembled homologous cDNA sequences, a full-length cDNA of 633 bp for BoDHAR was cloned by RT-PCR. Furthermore, we have experimentally cloned and sequenced the 5' flanking sequence of gene BoDHAR by genomic walking method based on ligation-mediated PCR. The full length DNA sequence with 1486bp, containing two introns, was achieved. Homologous analysis shows that gene has 82.3% identity at nucleotide level, and 79.6% identity at amino acid level with Arabidopsis dehydroascorbate reductase (DHAR) gene AT1 G19570.1. Structurally, BoDHAR encodes a polypeptide of 210 amino acids, which contains a GST-c-DHAR domain highly conserved among other members of the DHAR superfamily and has multiple phosphorylation sites. Promoter predictions software indicated that the 5' upstream region contained putative transcription signals and conserved sequences, one CAAT-box, one G-box and four TGAC-like motifs. To advance our understanding of gene BoDHAR, tissue expression pattern were analyzed by semi-quantitative RT-PCR. The results indicate that expression level of gene BoDHAR is higher in fertile buds than that in sterile buds, and expressed intensively in the anther.