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Organic-inorganic hybrid metal halides have attracted significant attention in recent years due to their excellent optoelectronic properties and potential applications in solar cells. Herein, the organic-inorganic hybrid molecule [N,N-dimethyl-1,3-propanediamine]SbBr5 (1) was synthesized by reacting a long-chain organic diamine N,N-dimethyl-1,3-propanediamine with SbBr3 as a metal halide precursor in HBr aqueous solution. Compound 1 possesses a one-dimensional chainlike structure with the second-harmonic generation switch and two continuous phase transitions above room temperature. The band gap of compound 1 is about 2.62 eV, exhibiting a semiconductive property, which may have important implications for the development of new optoelectronic devices.
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Reactions of a chiral and quasi-spherical molecule [1S,4S-2,5-2.2.1-H2dabch]I2 (1) with alkali metal halide MX (M = Na, K, Cs; X = Cl, Br) at room temperature produced a series of organic-inorganic hybrid (OIH) materials [1S,4S-2,5-2.2.1-H2dabch]NaBr3 (2), [1S,4S-2,5-2.2.1-H2dabch]CsCl3·H2O (3) and [1S,4S-2,5-2.2.1-H2dabch]KBr3·H2O (4). The single-crystal X-ray diffraction analysis revealed that the organic-inorganic framework structures comprised of the templating ligand and alkali metal halides (NaBr, CsCl, KBr) displayed dimensions spanning from one-dimensional (1D) to three-dimensional (3D). Moreover, the results of both differential scanning calorimetry (DSC) and dielectric measurements demonstrated that compounds 1-4 displayed reversible, high-temperature phase transitions and noticeable dielectric anomalies. In addition, the temperature-dependent second harmonic generation (SHG) results revealed crystals 1 and 3 can switch from the SHG-ON to the SHG-OFF state, which was proved by the variable-temperature X-ray diffraction. This research aims to streamline the exploration of multifunctional second harmonic generation (SHG) and dielectric materials that have been synthesized using chiral ligands and alkali metals. This will provide researchers with enhanced opportunities to delve further into this specific research domain.
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A protocol for the synthesis of α-amino-vinylphosphine oxides by phosphinoenamination reaction between alkyl nitriles and phosphine oxides was developed. The combination of Mn(OAc)2 as a Lewis acid and guanidine as a Lewis base was found to be an efficient catalytic system for this reaction. A series of alkyl nitriles and phosphine oxides are compatible with this conversion, furnishing the desired products in up to 95% yield under mild conditions. Furthermore, this method demonstrates the capability of gram-scale synthesis.
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Carborane compounds, known for their exceptional thermal stability and non-toxic attributes, have garnered widespread utility in medicine, supramolecular design, coordination/organometallic chemistry, and others. Although there is considerable interest among chemists, the integration of suitable carborane molecules into ferroelectric materials remains a formidable challenge. In this study, we employ the quasi-spherical design strategy to introduce functional groups at the boron vertices of the o-carborane cage, aiming to reduce molecular symmetry. This approach led to the successful synthesis of the pioneering ferroelectric crystals composed of cage-like carboranes: 9-OH-o-carborane (1) and 9-SH-o-carborane (2), which undergo above-room ferroelectric phase transitions (Tc) at approximately 367â K and 347â K. Interestingly, 1 and 2 represent uniaxial and multiaxial ferroelectrics respectively, with 2 exhibiting six polar axes and as many as twelve equivalent polarization directions. As the pioneering instance of carborane ferroelectric crystals, this study introduces a novel structural archetype for molecular ferroelectrics, thereby providing fresh insights into the exploration of molecular ferroelectric crystals with promising applications.
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BACKGROUND: Gastric cancer is a clinically common tumor, showing an upward trend of both incidence and mortality. GRB7 has been identified as a vital regulator in tumor progression. This study aims to uncover the biological function of GRB7 in gastric cancer process. METHODS: immunohistochemical (IHC) staining using a tissue microarray (TMA), quantitative reverse transcription PCR (qRT-PCR) and Western blotting were performed to detect the expression of genes. Furthermore, gastric cancer cell lines AGS and MGC-803 were transfected with short hairpin RNAs against GRB7. The biological function of GRB7 in gastric cancer cells were examined by CCK-8, flow cytometry, wound healing and Transwell assays. Then, in vivo tumor formation assay was conducted to explore the effects of GRB7 on tumor growth. Finally, expression levels of proteins related to cell functions were determined by Western blotting. Coimmunoprecipitation (CoIP) assay was performed to assess the protein-protein interaction. RESULTS: GRB7 was up-regulated in gastric cancer tissues and cell lines, and its expression was inversely proportional to survival of gastric cancer patients. Moreover, GRB7 knockdown inhibited proliferative, migratory abilities, as well as promoted cell apoptosis in gastric cancer cells. Further study suggested that GRB7 silencing could suppress gastric cancer tumor growth in vivo. Furthermore, our study uncovered an important interaction between GRB7 and MyD88. Silencing MyD88 was observed to alleviate the malignant phenotypes promoted by GRB7 in gastric cancer cells. CONCLUSIONS: Together, this study provided evidence that GRB7 may be an effective molecular targets for the treatment of gastric cancer.
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Neoplasias Gástricas , Humanos , Línea Celular Tumoral , Neoplasias Gástricas/patología , Factor 88 de Diferenciación Mieloide/genética , Proliferación Celular/genética , ARN Interferente Pequeño , Regulación Neoplásica de la Expresión Génica , Movimiento Celular/genética , Proteína Adaptadora GRB7/genética , Proteína Adaptadora GRB7/metabolismoRESUMEN
A method is presented for decarboxylative alkoxy-alkoxycarbonylation of various alkenes with alcohols by electrochemical anodic oxidation of monopotassium ethyloxalate salts with good functional group compatibility. The reaction involves anodic oxidation to form an acyl radical, followed by addition to an olefin to yield a new alkyl radical, which is anodically oxidized to a carbon cation and captured by alcohols to afford ß-alkoxyalkanoates. Adding catalytic amounts of ammonium iodide enhanced the efficiency of the reactions.
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OBJECTIVE: To investigate the value of 99mTc-pertechnetate scan in postoperative differentiated thyroid cancer (DTC) patients with lymph node (LN) metastases (LNM) uptake 99mTc-pertechnetate, especially the predictive value to their response to radioiodine-131 (131I) therapy. METHODS: This retrospective study collected 752 patients with DTC and LNM treated at Zhejiang Cancer Hospital between May 2012 and December 2017. Depending on the ability of LNM uptake 99mTc-pertechnetate, the patients were grouped as the 99mTc-pertechnetate-avid (n=88) vs. 99mTc-pertechnetate-non-avid (n=664) groups. And Propensity score matching (PSM) was performed at a 1:4 ratio to reduce confounding bias. RESULTS: In the PSM analysis, the 1:4 matched cohort comprised 752 patients (88 with 99mTc-pertechnetate-avid LNM, 664 with 99mTc-pertechnetate-non-avid LNM). Patients' age, initial 131I activity and frequency of iodine therapy were included as covariates. After PSM analysis, 363 patients (99mTc-pertechnetate-avid group, n=83; 99mTc-pertechnetate-non-avid group, n=280) were successfully matched. Among the 363 PSM-matched patients, 48/83 (57.8%) in the 99mTc-pertechnetate-avid group and 158/280 (56.4%) in the 99mTc-pertechnetate-non-avid group had two or more 131I treatments. The nsTg and the percentage of changes in ssTg between the 99mTc-pertechnetate-avid and 99mTc-pertechnetate-non-avid groups were significantly different ([0.05 (0.04 to 0.90) vs. 0.40 (0.04 to 4.92), p=0.018] and [-88% (-98%, -50%) vs. -66% (-86%, -30%), p < 0.001], respectively). No significant differences were observed between the two groups in the other parameters (age, pathological type, distant metastasis, follow-up time, AJCC TNM stage, initial 131I treatment activity, and 131I treatment frequency) after PSM (all p > 0.05). CONCLUSION: In patients with DTC and LNM, LNM uptake of 99mTc-pertechnetate is a rare phenomenon. Patients with 99mTc-pertechnetate-avid LNMs were more likely to benefit from 131I therapy, even after adjustment for age, 131I treatment frequency, and initial 131I activity.
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Juglans sigillata Dode is one of the important tree species in southwest China, and it has significant economic and ecological value. However, there is still a lack of effective methods to identify the functional genes of J. sigillata. By verifying the model plant tobacco, the pTRV2::JsPDS vector was able to cause photobleaching. This study showed that photobleaching occurred 24 and 30 d after the silencing vector was infected with aseptic seedlings and fruits of J. sigillata, respectively. When the OD600 was 0.6, and the injection dose was 500 µL, the gene silencing efficiency of aseptic seedlings was the highest at 16.7 %, significantly better than other treatments. Moreover, when the OD600 was 0.8, and the injection dose was 500 µL, the gene silencing efficiency in the walnut fruit was the highest (20 %). In addition, the VIGS system was successfully used to silence JsFLS2 and JsFLS4 genes in J. sigillata. This study also showed that the flavonol content and gene expression in the treatment group were decreased compared to the control group. In addition, the proteins transcribed and translated from the JsFLS4 gene may have higher catalytic activity for dihydroquercetin. The above results indicate that the TRV-mediated VIGS system can be an ideal tool for studying J. sigillata gene function.
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Juglans , Virus de Plantas , Juglans/genética , Silenciador del Gen , Fenotipo , Frutas , Nicotiana , Plantones/genética , Regulación de la Expresión Génica de las Plantas , Virus de Plantas/genéticaRESUMEN
Reported herein is a photochemical strategy for C(sp3)-H azolation of ethers via a hydrogen-atom transfer and radical-polar crossover process, offering efficient access to valuable N-alkylated azoles under visible-light irradiation. The protocol is metal-free and photocatalyst-free, and exhibits good to excellent yields and broad substrate scope with regard to azoles. EPR experiments provide evidence for the formation of intermediates formed in situ.
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An enantioselective Pd-catalyzed intramolecular desymmetrizing cycloisomerization of N-(cyclopent-3-en-1-yl)propiolamides has been developed by employing a new chiral phosphoramidite ligand. A series of structurally unique bridged azabicycles are achieved in moderate to excellent yields with good E/Z selectivity and high enantioselectivity. Synthetic transformations are conducted to demonstrate the practical utility of this reaction.
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Arylamines, serving as crucial building blocks in natural products and finding applications in multifunctional materials, are synthesized on a large scale via an electrophilic nitration/reduction sequence. However, the current methods for aromatic C-H amination have not yet attained the same level of versatility as electrophilic nitration. Here we show an extensively investigated transition metal-free and regioselective strategy for the amination of nitrobenzenes, enabling the synthesis of 4-nitro-N-arylamines through C(sp2)-H/N-H cross-coupling between electron-deficient nitroarenes and amines. Mechanistic studies have elucidated that the crucial aspects of these reactions encompass the generation of nitrogen radicals and recombination of nitrobenzene complex radicals. The C(sp2)-N bond formation is demonstrated to be highly effective for primary and secondary arylamines as well as aliphatic amines under mild conditions, exhibiting exceptional tolerance towards diverse functional groups in both nitroarenes and amines (>100 examples with yields up to 96%). Notably, this C(sp2)-H/N-H cross-coupling exhibits exclusive para-selectivity.
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Reported herein is direct C(sp3)-H arylation of unprotected benzyl anilines and alkylarenes via consecutive photoinduced electron transfer by visible light irradiation. Reductive quenching cycles and radical-radical cross-coupling were involved, and electron paramagnetic resonance experiments provide evidence for the formation of radical intermediates formed in situ. The protocol highlights transition metal free, external oxidant free, broad substrate scope, and high efficiency (>60 examples, up to 96%).
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Recent advances in heart-on-a-chip systems hold great promise to facilitate cardiac physiological, pathological, and pharmacological studies. This review focuses on the development of heart-on-a-chip systems with tissue-specific functionalities. For one thing, the strategies for developing cardiac microtissues on heart-on-a-chip systems that closely mimic the structures and behaviors of the native heart are analyzed, including the imitation of cardiac structural and functional characteristics. For another, the development of techniques for real-time monitoring of biophysical and biochemical signals from cardiac microtissues on heart-on-a-chip systems is introduced, incorporating cardiac electrophysiological signals, contractile activity, and biomarkers. Furthermore, the applications of heart-on-a-chip systems in intelligent cardiac studies are discussed regarding physiological/pathological research and pharmacological assessment. Finally, the future development of heart-on-a-chip toward a higher level of systematization, integration, and maturation is proposed.
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Halogen engineering offers a means of enhancing the physical properties of materials by fine-tuning the rotational energy barrier and dipole moment, which proved to be effective in achieving switchable phase transitions and optical responses in materials. In this work, by substituting the methyl group in ligand N-ethyl-1,5-diazabicyclo[3.3.0]octane (CH3CH2-3.3.0-Dabco) with halogen atoms X (Cl or Br) and then contining to react it with FeBr3 in a HBr aqueous solution, we successfully synthesized three kinds of organic-inorganic hybrid switchable phase-change materials, [CH3CH2-3.3.0-Dabco]FeBr4 (1), [ClCH2-3.3.0-Dabco]FeBr4 (2), and [BrCH2-3.3.0-Dabco]FeBr4 (3), which were fully characterized by single-crystal X-ray diffraction and variable-temperature powder X-ray diffraction. Compared to compound 1, compounds 2 and 3 show two pairs of reversible phase transitions, dielectric anomalies, and a second-harmonic-generation effect, which are successfully induced due to the halogen substitution. This study offers an effective molecular design strategy for the exploration and construction of iron halide organic-inorganic hybrid materials with temperature-adjustable physical properties.
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The trace chemical components in functional Monascus rice were studied to explore the potential bioactive substances. MCI column, Sephadex LH-20 gel, and preparative liquid chromatography were used to purified the ethyl acetate extract from functional Monascus rice. Two novel pyridine Monascus pigments were isolated and identified, named monascopyridine G (1) and monascopyridine H (2), respectively based on extensive mass spectrometry (MS), infrared radiation (IR), and nuclear magnetic resonance (NMR) analysis. The molecular docking experiments between compounds 1 and 2 and peroxisome proliferators-activated receptor-gamma (PPARγ) showed that they exhibited obvious binding force with the receptor protein. Besides, the biosynthetic pathways of the two compounds were proposed, which provide a valuable reference for the selective production of these potential bioactive substances.
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Objective: Peptidyl alkaloids, a series of important natural products can be assembled by fungal non-ribosomal peptide synthetases (NRPSs). However, many of the NRPSs associated gene clusters are silent under laboratory conditions, and the traditional chemical separation yields are low. In this study, we aim to discovery and efficiently prepare fungal peptidyl alkaloids assembled by fungal NRPSs. Methods: Bioinformatics analysis of gene cluster containing NRPSs from the genome of Penicillium thymicola, and heterologous expression of the putative gene cluster in Aspergillus nidulans were performed. Isolation, structural identification, and biological evaluation of the product from heterologous expression were carried out. Results: The putative tri-modular NRPS AncA was heterologous-expressed in A. nidulans to give anacine (1) with high yield, which showed moderate and selective cytotoxic activity against A549 cell line. Conclusion: Heterologous expression in A. nidulans is an efficient strategy for mining fungal peptidyl alkaloids.
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italic>Shiraia bambusiccola is an important medicinal fungus in China. Hypocrellins with perylenequinone skeleton are main bioactive components of Shiraia bambusiccola, which are widely used in food, medicine, pesticide and other fields as natural photosensitizers. For example, "hypocrellin ointment" has already been used clinically. As a rare and vulnerable species, wild Shiraia bambusiccola resources are very limited. Due to the complex structure and chanllenge in chemical total synthesis of hypocrellins, it is urgent to find an effective strategy to rationally utilize its medicinal value while protecting the wild resources. In this study, a candidate gene cluster hpc was identified in Shiraia sp. cfcc 84681 based on careful bioinformatic analysis. A heterologous expression system for hpc gene cluster was successfully constructed and a mutant strain with high yield of hypocrellins was obtained, which mainly produced hypocrellin A and isohypocrellin A. The main ingredients in the mutant strain are consistent with that in the wild Shiraia bambusiccola. These results provide a new strategy to solve the shortage of wild Shiraia bambusiccola resources.
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Six novel monacolin analogs, monacolins V-V (1-6), together with seven known ones (7-13), were isolated from the ethyl acetate extract of red yeast rice. Their structures and absolute configurations were determined by spectroscopic methods, especially 2D NMR (H-HCOSY, HSQC, HMBC, and NOESY/ROESY) and CD spectroscopic analyses as well as chemical derivation. Monacolins V (2) and V (3) represent the first examples of monacolins with 3-hydroxybutyrate substitute. The anti-inflammatory inhibitory activities against the lipopolysaccharide (LPS) induced NO production in BV-2 cells as well as antioxidant activities against rat liver microsomal lipid peroxidation were evaluated.
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Trace chemical constituents from the ethyl acetate extract of Red Yeast Rice were investigated. Four phenolic compounds were isolated by various column chromatographies, and their structures were identified on the basis of spectroscopic analysis including UV, MS, IR and NMR. The four compounds were identified as 2-methyl-5-(2'R-methyl-4'-hydroxy-butyl)-cinnamic acid(1), 5-(2'-hydroxy-6'-methyl phenyl)-3-methylfuran-2-carboxylic acid(2), daidzein(3), and genistein(4). Compound 1 was new and 2 was firstly discovered from the genus Monascus, while 3-4 were obtained from Red Yeast Rice for the first time.
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Productos Biológicos , Química , Espectroscopía de Resonancia Magnética , Monascus , Fenoles , QuímicaRESUMEN
To report on the validity and reliability of the Chronic Liver Disease Questionnaire (CLDQ) for assessing subjects with posthepatitic B cirrhosis. The CLDQ was administered to 117 healthy volunteers and 297 patients with posthepatitic B cirrhosis. All posthepatic B cirrhosis patients were assessed for the Child-Pugh stage. The entire questionnaire and each individual item was analyzed for precision and reliability. Exploratory factor analysis, responsiveness, and discrimination validity were also assessed. No significant floor effects were detected, but a moderate ceiling effect (less than 30%) was found for the following subscales: abdominal symptoms (AS), activity (AC), and worry (WO). For most items, the ceiling effect was between 30% to 60%. The internal consistency (Cronbach's a) on total scale level was good (a = 0.905), and ranged from 0.442 to 0.848 for the different subscales. The correlation coefficients of the total scale with subscales were above 0.6 (P less than 0.01) for reliability. The CLDQ and subscale scores for healthy controls were higher than those for the patients (P less than 0.001), and were gradated from the patients with Child-Pugh A cirrhosis to those with Child-Pugh B or C cirrhosis. Increase in severity of liver disease was accompanied by lower scores by the CLDQ and 4 out 6 subscales. Exploratory factor analysis moderately reproduced the original factor structure. The CLDQ has good reliability, satisfactory content, responsiveness and discriminant validity, and moderate precision and construct validity. It is useful for effectively evaluating health-related quality of life and curative effect in patients with posthepatitic B cirrhosis.