Both solitary and tandem applications of residual chemical shift anisotropy (RCSA) and residual dipolar coupling (RDC) show great potential for the structural and configurational determination of organic molecules. A critical component of both RDC and RCSA methodologies is the alignment medium, whose availability is limited, especially for RCSA measurement. Moreover, reported RDC and RCSA acquisitions mainly rely on two experiments conducted under two different conditions, which are relatively time-consuming and easily cause experimental errors.
View Article and Find Full Text PDFIn order to explore the effects of continuous annual crop rotation and fallow on aggregate stability and organic carbon content in red soil, the red soil in sloping farmland was taken as the research object, and the water-stable aggregates and organic carbon content were determined using the wet sieve method and potassium dichromate-concentrated sulfuric acid external heating method, respectively. The changes in soil aggregate stability and organic carbon content under the four treatments of maize-vetch-maize rotation (M-V-M), maize-pea-maize rotation (M-P-M), maize-fallow-maize (M-F-M), and annual fallow (F-F-F) from 2020 to 2022 and the relationships between them were analyzed. The results showed that in 2021 and 2022, the contents of > 2 mm aggregates treated with F-F-F, M-V-M, and M-P-M were significantly increased by 67.
View Article and Find Full Text PDFA novel Zn coordination polymer, namely, poly[{μ-bis[4-(2-methyl-1H-imidazol-1-yl)phenyl]methanone-κN:N}(μ-5-bromobenzene-1,3-dicarboxylato-κO:O)zinc(II)], [Zn(CHBrO)(CHNO)] or [Zn(Br-BDC)(MIPMO)], (I), has been synthesized by the solvothermal method using 5-bromoisophthalic acid (Br-HBDC), bis[4-(2-methyl-1H-imidazol-1-yl)phenyl]methanone (MIPMO) and Zn(NO)·6HO. Structure analysis showed that compound (I) displays twofold parallel interwoven sql nets. Fluorescence experiments confirmed that the compound can sensitively and selectively detect nitrofurantoin (NFT) in aqueous medium.
View Article and Find Full Text PDFThe formation of lyotropic liquid crystals (LCs) in two-dimensional (2D) colloidal dispersions enables the production of mesoscopic/macroscopic ordered materials from nanoscale building blocks. In contrast to graphene oxide (GO) LCs, the practical applications of MXene LCs are less exploited. This study bridges the gap by utilizing a simple and versatile fabrication method to prepare TiCT MXene LC that can be applied as a background-free alignment medium for the residual dipolar coupling (RDC) measurement of organic molecules.
View Article and Find Full Text PDFTwo new bifunctional isolated hybrid compounds, [ε-PMoV8MoVI4O37(OH)3Zn4][iql]4·6H2O (1) and [ε-PMoV8MoVI4O38(OH)2Zn4][bipy]3[(CH3COO)(bipy)2Zn]·2H2O (2) (where iql = isoquinoline and bipy = 2,2'-bipyridine), based on Zn-ε-Keggin were successfully synthesized by self-assembly under hydrothermal conditions. It is interesting to note that acetate in 2 acted as a linker connecting the ε-Keggin anion with the one Zn atom (Zn5) and enabled the ε-Keggin anion to coordinate with more bipy ligands, culminating with a larger isolated system, which is the first reported isolated cluster of Zn5PMo12. Meanwhile, compounds 1-2 show great electrochemical behaviors and excellent electrocatalytic activity for the degradation of NaNO2.
View Article and Find Full Text PDFA novel three-dimensional (3D) Zn coordination polymer, namely, poly[[[1,4-bis(pyridin-4-yl)benzene](μ-3,3'-{[1,3-phenylenebis(methylene)]bis(oxy)}dibenzoato)zinc(II)] 1,4-bis(pyridin-4-yl)benzene], {[Zn(CHO)(CHN)]·CHN} or {[Zn(PMBD)(DPB)]·DPB}, 1, where HPMBD is 3,3'-{[1,3-phenylenebis(methylene)]bis(oxy)}dibenzoic acid and DPB is 1,4-bis(pyridin-4-yl)benzene, has been synthesized by self-assembly using zinc nitrate, a semi-rigid dicarboxylic acid and a nitrogen-containing ligand. The single-crystal X-ray structure determination indicates that 1 possesses an intriguing 3D architecture with a 4-connected uninodal cds topology, which is constructed from dinuclear {Zn} clusters and V-shaped PMBD linkers. Compound 1 exhibits excellent photocatalytic activity on the degradation of the organic dyes Rhodamine B (RhB), Rhodamine 6G (Rh6G) and Methyl Red (MR).
View Article and Find Full Text PDFBackground: Secretory Carrier Membrane Proteins 3 (SCAMP3) is a transmembrane protein that affects intracellular trafficking, protein sorting and vesicle formation. Overexpression of SCAMP3 correlates with poorly differentiated hepatocellular carcinoma (HCC). However, the expression and corresponding gene regulation of SCAMP3 in HCC remain unclear.
View Article and Find Full Text PDFA three-dimensional polymolybdate-based metal-organic framework (POMOF) consisting of Zn-ε-Keggin unit and organic linker, {[PMoMoO(OH)Zn][BPE]}·[BPE] (), was successfully obtained by the hydrothermal method. Compound is composed of Zn-ε-Keggin units and BPE ligands, featuring a fascinating 5-fold interpenetrating framework with topology. The catalytic performance of compound was investigated, and experiments showed that could effectively facilitate the cycloaddition reaction of CO with epoxides as Lewis acid heterogeneous catalyst.
View Article and Find Full Text PDFBy using a semi-rigid tripodal ligand 5-(4-carboxybenzyloxy)isophthalic acid (HL) and lanthanide metal ions (Nd, Tb), two novel lanthanide metal-organic frameworks, namely, {[NdL(DMF)4] DMF} (), and {TbL(DMF)(HO)} (), were synthesized under mild solvothermal conditions and structurally characterized by X-ray single crystal diffraction. Compounds and are isostructural, in which L ligands linked dinuclear lanthanide metal-carboxylate units to form non-interpenetrated 3D network with (3,6)-connected topology. Luminescent investigations reveal that compound displays the near-infrared emission at room temperature, and compound can be employed as selective probe for CrO anion in aqueous solution based on luminescence quenching.
View Article and Find Full Text PDFWe demonstrate a stable, picosecond fiber laser mode-locked by cesium lead halide perovskite quantum dots (CsPbBr-QDs). The saturable absorber is produced by depositing the CsPbBr3-QDs nanocrystals onto the endface of a fiber ferrule through light pressure. A balanced two-detector measurement shows that it has a modulation depth of 2.
View Article and Find Full Text PDFGestational trophoblastic disease (GTD) encompasses a range of trophoblast-derived disorders. The most common type of GTD is hydatidiform mole (HM). Some of HMs can further develop into malignant gestational trophoblastic neoplasia (GTN).
View Article and Find Full Text PDFFetal growth restriction (FGR) threatens perinatal health and is correlated with increased incidence of fetal original adult diseases. Most cases of FGR were idiopathic, which were supposed to be associated with placental abnormality. Decreased circulating placental growth factor (PGF) was recognized as an indication of placental deficiency in FGR.
View Article and Find Full Text PDFCompr Rev Food Sci Food Saf
March 2017
Glycidyl fatty acid esters (GEs), one of the main contaminants in processed oils, are mainly formed during the deodorization step in the refining process of edible oils and therefore occur in almost all refined edible oils. GEs are potential carcinogens, due to the fact that they readily hydrolyze into the free form glycidol in the gastrointestinal tract, which has been found to induce tumors in various rat tissues. Furthermore, glycidol has already been identified as a "possible human carcinogen'' (group 2A) by the Intl.
View Article and Find Full Text PDFAim: The expression of aromatase (via CYP19 and the CYP19 PII promoter) and the orphan nuclear receptor family members, liver receptor homologue-1 (LRH-1) and steroidogenic factor-1 (SF-1) in cultured luteinized granulosa cells from women with endometriosis were investigated.
Methods: Luteinized granulosa cells from patients undergoing in vitro fertilization (16 patients with endometriosis and 28 controls) were examined for messenger ribonucleic acid (mRNA) expression of CYP19, CYP19 PII, LRH-1 and SF-1, determined by quantitative reverse transcription-polymerase chain reaction. Student's t-test, the Mann-Whitney U test and Spearman's rank correlation were used for statistical analysis.
Epidemiological evidence suggests that elevated androgen levels and genetic variation related to the androgen receptor (AR) increase the risk of endometrial cancer (EC). However, the role of AR in EC is poorly understood. We report that two members of the histone demethylase KDM4 family act as major regulators of AR transcriptional activityin EC.
View Article and Find Full Text PDFEpithelial-mesenchymal transition (EMT) is associated with the metastasis and poor prognosis of cervical cancer. However, the underlying mechanisms are poorly defined. In the present study, we investigated whether Twist plays a direct role in human cervical cancer using immunohistochemical and western blot analyses.
View Article and Find Full Text PDFBackground: Pregnancy-induced or gestational hypertension is a common pregnancy complication. Paradoxically, gestational hypertension has been associated with a protective effect against perinatal mortality in twin pregnancies in analytic models (logistic regression) without accounting for survival time. Whether this effect is real remains uncertain.
View Article and Find Full Text PDFThe alterations of MicroRNAs(miRNAs) in host cell after foot-and-mouth disease virus (FMDV) infection is still obscure. To increase our understanding of the pathogenesis of FMDV at the post-transcriptional regulation level, Solexa high-throu MicroRNAs (miRNAs) play an important role both in the post-transcriptional regulation of gene expression and host-virus interactions. Despite investigations of miRNA expression ghput sequencing and bioinformatic tools were used to identify differentially expressed miRNAs and analyze their functions during FMDV infection of PK-15 cells.
View Article and Find Full Text PDFThe molecular mechanism involved in the metastasis of endometrial cancer (EC) remains unclear. The lysosomal cysteine protease Cathepsin B has been implicated in the progression of various human tumors. In the present study, we assessed the expression of Cathepsin B and its functions in EC.
View Article and Find Full Text PDFBackground: Dehydroepiandrosterone (DHEA) is widely known for its beneficial effect on postmenopausal osteoporosis, although the underlying mechanisms remain mainly unclear. In this study, we tried to determine the activation of mitogen-activated protein kinase signal pathways during DHEA treatment and the indirect role of osteoblasts (OBs) on osteoclasts under the DHEA treatment of postmenopausal osteoporosis.
Methods: Primary human OBs and osteoclast-like cells were cultured and, we pretreated OBs with or without U0126 (a highly selective inhibitor of both MEK1 and MEK2).
Zhonghua Fu Chan Ke Za Zhi
September 2011
Objective: To investigate the selective mechanism of dehydroepiandrosterone (DHEA) for osteoblast via ERβ.
Methods: High expression of ERβ in hMG63-ERβ group (infected with pWPT-ERβ), gene silencing of ERβ in hMG63-shERβ group (infected with pLVTHM-GFP/ERβ-shRNA) and hMG63 group (control) were cultured and treated with 1×10(-7) mol/L DHEA, with or without U0126 and etoposide. The proliferation and apoptosis of hMG63 were evaluated by flow cytometry.
Zhonghua Fu Chan Ke Za Zhi
December 2009
Objective: To study whether the primary ovarian cancer cells containing cancer stem cells and its characterization in serum-free culture condition.
Methods: The primary cancer cells were isolated from one stage III, grade 2 serous adenocarcinoma tissue. Cells were cultured in serum-free culture system supplemented with epidermal growth factor, basic fibroblast growth factor, leukemia inhibitory factor and insulin, or standard serum-containing system.
Zhonghua Fu Chan Ke Za Zhi
August 2008
Objective: To study the clinical characteristics, the outcome of pregnancy and the risk factors of uteroplacental apoplexy complicating severe placental abruption.
Methods: A retrospectively study of the 52 cases of placental abruption who had delivered in our hospital from Jan. 2002 to Dec.