A rapid responsive coumarin-naphthalene derivative for the detection of cyanide ions in cell culture.

Cyanide ion (CN-) is widely used in many industrial processes; however, it causes several diseases in humans. Therefore, rapid and accurate detection of CN- is very important and urgent. In this study, a CN- sensor (MH-2) which was capable of detecting CN- ions in living cell was developed. MH-2 gives a rapid color change, absorbance and fluorescence response to CN- in the presence of the anions tested in the working system. The binding ratio between the sensor and CN- was demonstrated by some spectrophotometric methods and the sensing mechanism was investigated by NMR titration experiments, suggesting that MH-2 gives response to CN- via the nucleophilic addition reaction. The fluorescence detection limit and the absorbance detection limit were calculated as 0.056 µM and 0.11 µM, respectively. Both of these detection limits are below the tolerable limit recommended by WHO for CN- in the drinking water (1.9 µM). MH-2 was also applied to living cells for bio-imaging and the results showed that the sensor penetrates the cells and can detect cyanide ions in living cells.

Elevated Angiogenic Factor Levels After Transarterial Radioembolization for Colorectal Cancer Liver Metastases May Predict a Poor Prognosis.

Objectives: To analyze the change in circulating angiogenic factor levels after transarterial radioembolization (TARE) for colorectal cancer liver metastases (CRCLMs) and its prognostic significance. Methods: Blood samples immediately before TARE and on 1 day, 1 week and 6 weeks after were collected for angiogenic factor analysis in 23 patients. Results: Patients with elevated serum basic fibroblast growth factor and platelet-derived growth factor levels in the 1st week and vascular endothelial growth factor (VEGF) levels in the 6th week after TARE had significantly shorter median overall survival (OS) times. Conclusion: Some early increases in serum angiogenic factor levels and in serum VEGF in the 6th week after TARE for CRCLMs are related to short OS and progression-free survival.

Determination of pentraxin 3 levels in diagnosis of appendicitis in children.

BACKGROUND: The aim of this study is to determine whether pentraxin 3 (PTX3) levels can be used in the diagnosis of appendicitis in children. METHODS: Fifteen children under 18 years old, who gave blood samples for reasons other than inflammatory conditions, and 40 children who were proved to have appendicitis (non-perforated or perforated) between August 2017 and January 2018, were enrolled in the study. Patients were classified into subgroups: group 1 (healthy children without any sign of inflammation, n = 15), group 2 (non-perforated appendicitis, n = 25), and group 3 (perforated appendicitis, n = 15). RESULTS: The median PTX3 value was 1.01 ng/mL (minimum value: 0.82, maximum: 1.28) in the control group. The median PTX3 values prior to surgery were 20.68 ng/mL (minimum: 1.02, maximum: 28.471) and 1.46 (minimum: 1.05, maximum: 23.421) ng/mL for non-perforated appendicitis and perforated appendicitis respectively. The PTX3 levels were significantly higher in groups 2 and 3 than in group 1 (P < 0.01). According to receiver operating characteristics analysis the cut-off value of PTX3 levels at admission for appendicitis was 1.30 ng/mL with a sensitivity of 75% and a specificity of 100% (area under the curve, 0.939; P = 0.000). CONCLUSIONS: Pentraxin 3 levels were significantly higher in children with appendicitis than in healthy children. Children with high PTX3 levels complaining of right lower quadrant pain may support a diagnosis of appendicitis. Future studies should be conducted to evaluate changes in PTX3 levels by comparing children with appendicitis versus acute abdominal pain in larger populations to further determine the value of PTX3 in the diagnosis of appendicitis in children.

Recent applications of chiral calixarenes in asymmetric catalysis.

The use of calixarenes in asymmetric catalysis is receiving increasing attention due to their tunable three-dimensional molecular platforms along with their easy syntheses and versatile modification at the upper and lower rims. This review summarizes the recent progress of synthesis and use of chiral calixarenes in asymmetric syntheses which emerged later than 2010.

Application of L-proline derivatives as chiral shift reagents for enantiomeric recognition of carboxylic acids.

Four proline-derived chiral receptors 5-8 were readily synthesized starting from L-proline. The enantiomeric recognition ability of chiral receptors was examined with a series of carboxylic acids by (1) H NMR spectroscopy. The molar ratio and the association constants of the chiral compounds with each of the enantiomers of guest molecules were determined by using Job plots and a nonlinear least-squares fitting method, respectively. The Job plots indicate that the hosts form 1:1 instantaneous complexes with all guests. The receptors exhibited different chiral recognition abilities toward the enantiomers of racemic guests. Among the chiral receptors used in this study, prolinamide 6 was found to be the best chiral shift reagent and is effective for the determination of the enantiomeric excess of chiral carboxylic acids.

Synthesis of chiral calix[4]arenes bearing aminonaphthol moieties and their use in the enantiomeric recognition of carboxylic acids.

Two armed chiral calix[4]arenes 8-16 functionalized at the lower rim with chiral aminonaphthol units have been prepared and the structures of these receptors characterized by FTIR, (1)H, and (13)C, DEPT and COSY NMR spectroscopy and elemental analysis. The enantioselective recognition of these receptors with various carboxylic acids has been studied by (1)H NMR and UV/Vis spectroscopy. The receptors exhibited different chiral recognition abilities towards the enantiomers of racemic materials and formed 2 : 1 or 1 : 1 complexes between host and guest. It was also demonstrated that chiral calix[4]arenes 9 and 16 could be used as chiral NMR solvating agents to determine the enantiomeric purity of mandelic acid.

Synthesis and dichromate anion sorption of silica gel-immobilized calix[4]arenes.

Three new silica gel-immobilized calix[4]arene polymers 9-11 have been prepared via modification of calix[4]arene mono amido derivatives 3-5 with 3-aminopropyl triethoxysilane (APTES) and activated silica gel, respectively. The polymers were characterized by Fourier transform infrared spectroscopy, elemental analysis and thermal gravimetric analysis. The solid-liquid extraction properties of ligands 3-5 along with their immobilized derivatives 9-11 towards dichromate (HCr(2)O(7)(-)/Cr(2)O(7)(2-)) anions were reported. It was found that these calix[4]arene-based polymers have high extraction abilities towards dichromate anions as compared to their monomeric precursors.

Chiral mono and diamide derivatives of calix[4]arene for enantiomeric recognition of chiral amines.

Novel chiral mono and diamide derivatives of calix[4]arene have been prepared from the aminolysis reaction of 5,11,17,23-tetra-tert-butyl-25,27-diethoxycarbonyl-methoxy-26,28-dihydroxycalix[4]arene 1 and 25,27-diethoxycarbonyl-methoxy-26,28-dihydroxycalix[4]arene 2 with chiral (S)-(-)-1-phenylethylamine (PEA) and (1S,2S)-(+)-2-amino-1-(4-nitrophenyl)-1,3-propanediol, respectively. Spectrophotometric titrations have been performed in CHCl(3) at 20-30 degrees C in order to obtain the binding constants (K) and the thermodynamic quantities (DeltaH and DeltaS) for the stoichiometric 1:1 inclusion complexation of various chiral amines with these new host compounds. Preliminary experiments were undertaken to confirm the complexation properties of receptors 9 and 13 with PEA by (1)H NMR in CDCl(3) at room temperature. The molecular recognition abilities and enantioselectivities for guests (R and S)-alpha-PEA and (R and S)-cyclohexylethylamine (CHEA) are discussed from a thermodynamic point of view.