Diagnostic utility of serum and urine biomarkers in idiopathic membranous nephropathy: a systematic review and meta-analysis.

BACKGROUND: Membranous nephropathy is an autoimmune nephropathy that is one of the most common pathological types of nephrotic syndrome. It is important to find and apply specific biomarkers for the noninvasive diagnosis of idiopathic membranous nephropathy (IMN). However, there are limited data about their diagnostic value. Therefore, an overall meta-analysis helps to identify effective biomarkers for the clinical diagnosis of IMN. METHODS: A systematic literature search was carried out in PubMed, Embase, Cochrane and Web of Science from inception until December 31, 2020. Two researchers searched for studies that met the inclusion criteria. The results of the joint study were expressed in terms of sensitivity and specificity. RESULTS: The meta-analysis included 24 studies with biomarkers for the clinical diagnosis of IMN, including antibody against phospholipase A2 receptor (PLA2R-AB), antibody against thrombospondin type I domain-containing 7A (THSD7A-AB), lysosome membrane protein-2 (LIMP-2) and circular RNAs. The diagnostic efficiency of PLA2R-AB for IMN had a combined sensitivity of 60% and a combined specificity of 100%. The diagnostic efficiency of THSD7A-AB for IMN had a combined sensitivity of 3% and a combined specificity of 99%. The diagnostic efficiency of urinary LIMP-2 for IMN was 100%, and the specificity was 100%. The diagnostic efficiency of exosomal circRNAs for IMN was 100%, and the specificity was 100%. CONCLUSIONS: This meta-analysis shows that PLA2R-AB and THSD7A-AB are of important diagnostic value for IMN. More studies are needed in the future to reveal the diagnostic value of LIMP-2 and circRNAs for IMN.

Efficacy and safety of remimazolam-based sedation for intensive care unit patients undergoing upper gastrointestinal endoscopy: a cohort study.

BACKGROUND: Remimazolam is a novel ultra-short-acting sedative, but its safety and adverse events (AEs) in high-risk patients in the intensive care unit (ICU) setting remain unknown. METHODS: This was a single-center, retrospective study that compared remimazolam to propofol and midazolam in patients undergoing upper gastrointestinal endoscopy. The primary outcome was the incidence of treatment-related AEs. The secondary outcomes were the time to extubation, the length of ICU stay, and the average cost of sedative per case. RESULTS: Of the 88 patients analyzed, 47 were treated with remimazolam (mean dose, 7.90±4.84 mg), and 41 were treated with propofol (21.19±17.98 mg) or midazolam (3.08±2.17 mg). There was no statistically significant difference in the average duration of the endoscopic procedure (35.89±13.37 min vs. 44.51±21.68 min, P=0.133) or the time to extubation (15.00±9.75 h vs. 20.59±18.71 h, P=0.211) in the remimazolam group (group I) compared to the propofol or midazolam group (group II). ICU stays (5.40±2.93 d vs. 4.63±3.31 d, P=0.072) and treatment-related AEs (48.61% vs. 51.38%, P=0.056) were similar between groups. The average cost of sedative per case was significantly lower in the group I than in the group II (RMB 16.07±10.58 yuan vs. RMB 24.37±15.46 yuan, P=0.016). CONCLUSION: Remimazolam-based sedation was noninferior to the classic sedatives and had lower average cost per case, indicating that it may be used as a promising sedative for high-risk patients during endoscopic procedures in the ICU setting.

Synthesis, structure and magnetocaloric properties of a new two-dimensional gadolinium(III) coordination polymer based on azobenzene-2,2',3,3'-tetracarboxylic acid.

A new Gd3+ coordination polymer (CP), namely, poly[diaqua[µ4-1'-carboxy-3,3'-(diazene-1,2-diyl)dibenzene-1,2,2'-tricarboxylato]gadolinium(III)], [Gd(C16H7N2O8)(H2O)2]n, (I), has been synthesized hydrothermally from Gd(NO3)3·6H2O and azobenzene-2,2',3,3'-tetracarboxylic acid (H4abtc). The target solid has been characterized by single-crystal and powder X-ray diffraction, elemental analysis, IR spectroscopy and susceptibility measurements. CP (I) crystallizes in the monoclinic space group C2/c. The structure features a 4-connected topology in which Gd3+ ions are connected by carboxylate groups into a linear chain along the monoclinic symmetry direction. Adjacent one-dimensional aggregates are bridged by Habtc3- ligands to form a two-dimensional CP in the (10-1) plane. A very short hydrogen bond [O...O = 2.4393 (4) Å] links neighbouring layers into a three-dimensional network. A magnetic study revealed antiferromagnetic Gd...Gd coupling within the chain direction. CP (I) displays a significant magnetocaloric effect (MCE), with a maximum -ΔSm of 27.26 J kg-1 K-1 for ΔH = 7 T at 3.0 K. As the MCE in (I) exceeds that of the commercial magnetic refrigerant GGG (Gd3Ga5O12, -ΔSm = 24 J kg-1 K-1, ΔH = 30 kG), CP (I) can be regarded as a potential cryogenic material for low-temperature magnetic refrigeration.

An ultra-sensitive selective fluorescent sensor based on a 3D zinc-tetracarboxylic framework for the detection and enrichment of trace Cu2+ in aqueous media.

Herein, a novel and fluorescent zinc-organic framework sensor [Zn3(µ3-Hbptc)2(µ2-4,4'-bpy)2(H2O)4]n·2nH2O (1) (H4bptc = 2,3,3',4'-biphenyl tetracarboxylic acid, 4,4'-bpy = 4,4'-bipyridine) is synthesized and characterized, demonstrating its excellent fluorescence performance for Cu2+ detection and the enrichment of Cu2+ in aqueous media. The fluorescence intensity of 1 can be selectively quenched by Cu2+ in a linear range of Cu2+ concentrations of 0-0.7 µM. The limit of detection (LOD) value is as low as 32.4 nM, which is superior to those of most of the fluorescent sensors based on metal-organic frameworks (MOFs). It is also far below the maximum allowable concentration of Cu2+ in drinking water as defined by the U.S. Environmental Protection Agency (EPA) and the World Health Organization (WHO), so it is employed for the detection of Cu2+ in actual water samples. More importantly, the nature of the interaction between the active coordination site (COO-) of 1 and Cu2+ determines the quenching mechanism, that is Cu2+ in the analyte is captured by MOF 1, which has been investigated by ICP, luminescence, UV-vis, XPS, and lifetime studies. Besides, the chemosensor shows regeneration performance without the loss of performance in five consecutive cycles. So MOF 1 is a simple and convenient probe used not only for the rapid detection but also for the enrichment of trace amounts of Cu2+ in aqueous media, and the application can be further extended to a variety of environmental and biological analysis processes.

A novel three-dimensional tetranuclear CoII coordination polymer with water hexamers based on the V-shaped tetracarboxylate ligand 4-(2,4-dicarboxylatophenoxy)phthalate.

A new coordination polymer (CP), namely, poly[[diaquatris[µ2-1,4-bis(1H-imidazol-1-yl)benzene]bis[µ6-4-(2,4-dicarboxylatophenoxy)phthalato]tetracobalt(II)] hexahydrate], {[Co4(C16H6O9)2(C12H10N4)3(H2O)2]·6H2O}n, has been synthesized by solvothermal reaction. The CP was fully characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, and powder and single-crystal X-ray diffraction. It presents a three-dimensional (3D) structure based on tetranuclear CoII secondary building units (SBUs) with a tfz-d net and point symbol (43)2(46·618·84). The 4-(2,4-dicarboxyphenoxy)phthalic acid (H4dcppa) ligands are completely deprotonated and link {Co4(COO)4}4- SBUs into two-dimensional (2D) layers. Furthermore, adjacent layers are connected by 1,4-bis(1H-imidazol-1-yl)benzene (bib) ligands, giving rise to a 3D supramolecular architecture. Interestingly, there are numerous elliptical cavities in the CP where isolated unique discrete hexameric water clusters have been observed. The results of thermogravimetric and magnetic analyses are described in detail.

A new family of lanthanide coordination polymers based on 3,3'-[(5-carboxylato-1,3-phenylene)bis(oxy)]dibenzoate: synthesis, crystal structures and magnetic and luminescence properties.

Six two-dimensional (2D) coordination polymers (CPs), namely, poly[{µ5-3,3-[(5-carboxylato-1,3-phenylene)bis(oxy)]dibenzoato-κ6O1:O1':O3,O3':O5:O5'}bis(N,N-dimethylformamide-κO)lanthanide(III)], [Ln(C21H11O8)(C3H7NO)2]n, with lanthanide/Ln = cerium/Ce for CP1, praseodymium/Pr for CP2, neodymium/Nd for CP3, samarium/Sm for CP4, europium/Eu for CP5 and gadolinium/Gd for CP6, have been prepared by solvothermal methods using the ligand 3,3'-[(5-carboxy-1,3-phenylene)bis(oxy)]dibenzoic acid (H3cpboda) in the presence of Ln(NO3)3. The complexes were characterized by single-crystal X-ray and powder diffraction, IR spectroscopy, elemental analysis and thermogravimetric analysis (TGA). All the structures of this family of lanthanide CPs are isomorphous with the triclinic space group P-1 and reveal that they have the same 2D network based on binuclear LnIII units, which are further extended via interlayer C-H...π interactions into a three-dimensional supramolecular structure. The carboxylate groups of the cpboda3- ligands link adjacent LnIII ions and form binuclear [Ln2(RCOO)4] secondary building units (SBUs), in which each binuclear LnIII SBU contains four carboxylate groups from different cpboda3- ligands. Moreover, with the increase of the rare-earth Ln atomic radius, the dihedral angles between the aromatic rings gradually increase. Magnetically, CP6 shows weak antiferromagnetic coupling between the GdIII ions. The solid-state luminescence properties of CP2, CP5 and CP6 were examined at ambient temperature and CP5 exhibits characteristic red emission bands derived from the Eu3+ ion (CIE 0.53, 0.31), with luminescence quantum yields of 22%. Therefore, CP5 should be regarded as a potential optical material.

Geranium and Lemon Essential Oils and Their Active Compounds Downregulate Angiotensin-Converting Enzyme 2 (ACE2), a SARS-CoV-2 Spike Receptor-Binding Domain, in Epithelial Cells.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as coronavirus disease-2019 (COVID-19), is a pandemic disease that has been declared as modern history's gravest health emergency worldwide. Until now, no precise treatment modality has been developed. The angiotensin-converting enzyme 2 (ACE2) receptor, a host cell receptor, has been found to play a crucial role in virus cell entry; therefore, ACE2 blockers can be a potential target for anti-viral intervention. In this study, we evaluated the ACE2 inhibitory effects of 10 essential oils. Among them, geranium and lemon oils displayed significant ACE2 inhibitory effects in epithelial cells. In addition, immunoblotting and qPCR analysis also confirmed that geranium and lemon oils possess potent ACE2 inhibitory effects. Furthermore, the gas chromatography-mass spectrometry (GC-MS) analysis displayed 22 compounds in geranium oil and 9 compounds in lemon oil. Citronellol, geraniol, and neryl acetate were the major compounds of geranium oil and limonene that represented major compound of lemon oil. Next, we found that treatment with citronellol and limonene significantly downregulated ACE2 expression in epithelial cells. The results suggest that geranium and lemon essential oils and their derivative compounds are valuable natural anti-viral agents that may contribute to the prevention of the invasion of SARS-CoV-2/COVID-19 into the human body.

Structural diversity, magnetic properties and luminescence of NiII, CoII and ZnII coordination polymers derived from 3,3'-[(5-carboxy-1,3-phenylene)bis(oxy)]dibenzoic acid and 1,10-phenanthroline.

Three novel coordination polymers (CPs), namely poly[[di-µ-aqua-bis{µ4-3,3'-[(5-carboxylato-1,3-phenylene)bis(oxy)]dibenzoato-κ5O1:O1',O3:O5:O5'}bis(1,10-phenanthroline-κ2N,N')trinickel(II)] dimethylformamide 1.5-solvate trihydrate], {[Ni3(C21H11O8)2(C12H8N2)2(H2O)2]·1.5C3H7NO·3H2O}n, (I), poly[[di-µ-aqua-bis{µ4-3,3'-[(5-carboxylato-1,3-phenylene)bis(oxy)]dibenzoato-κ5O1:O1',O3:O5:O5'}bis(1,10-phenanthroline-κ2N,N')tricobalt(II)] diethylamine disolvate tetrahydrate], {[Co3(C21H11O8)2(C12H8N2)2(H2O)2]·2C2H7N·4H2O}n, (II), and catena-poly[[aqua(1,10-phenanthroline-κ2N,N')zinc(II)]-µ-5-(3-carboxyphenoxy)-3,3'-oxydibenzoato-κ2O1:O3], [Zn(C21H12O8)(C12H8N2)(H2O)]n, (III), have been synthesized by the reaction of different metal ions (Ni2+, Co2+ and Zn2+), 3,3'-[(5-carboxy-1,3-phenylbis(oxy)]dibenzoic acid (H3cpboda) and 1,10-phenanthroline (phen) under solvothermal conditions. All the CPs were characterized by elemental analysis, single-crystal and powder X-ray diffraction, FT-IR spectroscopy and thermogravimetric analysis. Complexes (I) and (II) have isomorphous structures, featuring similar linear trinuclear structural units, in which the central NiII/CoII atom is located on an inversion centre with a slightly distorted octahedral [NiO6]/[CoO6] geometry. This comprises four carboxylate O-atom donors from two cpboda3- ligands and two O-atom donors from bridging water molecules. The terminal NiII/CoII groups are each connected to the central NiII/CoII cation through two µ1,3-carboxylate groups from two cpboda3- ligands and one water bridge, giving rise to linear trinuclear [M3(µ2-H2O)2(RCOO)4] (M = Ni2+/Co2+) secondary building units (SBUs) and the SBUs develop two-dimensional-networks parallel to the (100) plane via cpboda3- ligands with new (32·4)2(32·83·9)2(34·42.82·94·103) topological structures. Zinc complex (III) displays one-dimensional coordination chains and the five-coordinated Zn atom forms a distorted square-pyramidal [ZnO3N2] geometry, which is completed by two carboxylate O-atom donors from two distinct Hcpboda2- ligands, one O atom from H2O and two N atoms from a chelating phen ligand. Magnetically, CP (I) shows weak ferromagnetic interactions involving the carboxylate groups, and bridging water molecules between the nickel(II) ions, and CP (II) shows antiferromagnetic interactions between the Co2+ ions. The solid-state luminescence properties of CP (III) were examined at ambient temperature and the luminescence sensing of Cr2O72-/CrO42- anions in aqueous solution for (III) has also been investigated.

Structural diversity, magnetic property, or luminescence sensing of Co(ii) and Cd(ii) coordination polymers derived from designed 3,3'-((5-carboxy-1,3-phenylene)bis(oxy))dibenzoic acid.

Five novel coordination polymers (CPs), formulated as {[Co3(µ4-cpboda)2(µ1,1-OH2)2(2,2-bipy)2]·1.5DMF·2H2O}n (1), {[Co3(µ3-cpboda)2(4,4'-bpy)3(H2O)2]·4H2O}n (2), {[Co(µ2-H2cpboda)2(1,4-bib)3(H2O)2]·H2O·DMF·1.5HCOOH}n (3), [Cd(µ3-Hcpboda)(1,4-bib)]n (4), and {[Cd3(µ4-cpboda)2(µ1,1-OH2)2(phen)2]·2DMF·1.5H2O}n (5) (H3cpboda = 3,3'-((5-carboxy-1,3-phenylene)bis(oxy))dibenzoic acid, 2,2-bipy = 2,2-bipyridine, 4,4'-bpy = 4,4'-bipyridine, 1,4-bib = 1,4-di(1H-imidazol-1-yl)benzene, phen = 1,10-phenanthroline) have been synthesized under solvothermal conditions and characterized by elemental analyses (EAs), single-crystal X-ray diffraction analyses, X-ray powder diffraction analyses (PXRD), FT-IR spectra, and thermogravimetric analyses (TGAs). The structural analyses reveal that these complexes have four 2D coordinate polymers and one 3D framework, in which metal ions are in octahedral coordination geometries in 1-3 and 5, but seven-coordinated disordered pentagonal bipyramids in 4. Complexes 1 and 5 represent linear trinuclear [M3(µ1,1-OH2)2(µ1,3-COO)4] SBUs in 1 (M = Co(ii)) and in 5 (M = Cd(ii)) based on a 3,4,6-connected net with a point symbol (32·4)2(32·83·9)2(34·42·82·94·103) net, complex 2 exhibiting a (3-c)2(4-c)(4-c)2 3D structure with the (52·6·82·9)2(52·62·92)(52·6)2 topology and complexes 3 and 4 having a novel 2D framework with the point symbol of (44·62). Magnetization analyses disclose the antiferromagnetic (AF) behaviors between Co(ii) ions in complexes 1 & 3 and S = 3/2 (Co2+) spin Heisenberg chains with alternating magnetic sequences (F/F/AF)n in 2. Fluorescence measurements indicate that 4 and 5 are promising luminescence sensors for the detection of CrO42- and Cr2O72- anions in aqueous solution.

Three chiral one-dimensional lanthanide-ditoluoyl-tartrate bifunctional polymers exhibiting luminescence and magnetic behaviors.

Since Ln-CPs have excellent optical properties (higher color purity, longer fluorescence lifetime and higher quantum yield) and magnetic properties, it is of great significance to prepare dual magneto-optical materials based on Ln(iii). Herein, we obtained three versatile Ln-CPs, [Ln(HDTTA)3(CH3OH)3] n , derived from reactions of lanthanide salts (Ln = Tb 1, Dy 2, Ho 3) and a chiral and flexible ligand, namely, (+)-di-p-toluoyl-d-tartaric acid (d-H2DTTA) in a methanol-water solution, at room temperature and pressure. The structures of these compounds have been characterized by single crystal and powder X-ray diffraction, infrared spectroscopy, elemental analyses and thermogravimetric analyses. Complexes 1-3 are isomorphic, crystallizing in the chiral trigonal R3 space group with the linkage of Ln3+ ions and featuring 1D propeller chain structures. The circular dichroism spectra confirm that the complexes maintain the chirality from the ligands. Furthermore, the luminescent and magnetic properties have been investigated, relying on intrinsic properties of the lanthanide ions. The photoluminescence measurements indicate that 1, 2 and 3 show strong green, white and blue emission bands with CIE chromaticity coordinates of (0.32, 0.56), (0.29, 0.26) and (0.21, 0.12), respectively. The decay lifetime curve of 1 shows the exponential decay with long lifetime of 1.169 ms and the relative quantum yield for 1 was 19.31%. In addition, the magnetic properties of complexes 1-3 have been investigated by measuring the magnetic susceptibility in the temperature range of 2-300 K. They are all dominated by spin-orbit coupling and ligand field perturbation, and the exchange coupling between Ln3+ ions is almost negligible. Therefore, complexes 1-3 are promising chiral, optical and magnetic multifunctional materials.

Antioxidant Ability and Stability Studies of 3-O-Ethyl Ascorbic Acid, a Cosmetic Tyrosinase Inhibitor.

3-O-ethyl ascorbic acid may be a good whitening ingredient in cosmetics. However, before it can be successfully used in cosmetics, its biofunctionality and stability need to be comprehensively investigated. The reduction and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging ability of this compound were analyzed to assess its antioxidant potential. In addition, the tyrosinase inhibitory ability was analyzed to show the whitening capacity of 3-O-ethyl ascorbic acid. Response surface methodology (RSM) was used to determine the optimal conditions for the ascorbic acid derivative in cosmetics. Based on the DPPH radical scavenging ability results, the half-inhibitory concentration (IC50) value of 3-O-ethyl ascorbic acid was 0.032 g/L. It also showed a good reducing ability at 1.5 g/L concentration. Based on the tyrosinase inhibition analysis, the IC50 value was 7.5 g/L. The optimal conditions to achieve the best stability were determined from the RSM as 36.3°C and pH 5.46.

A thermally stable three-dimensional cobalt(II) coordination polymer based on the V-shaped ligand 4-(4-carboxyphenoxy)isophthalate.

A new cobalt(II) coordination polymer (CP), poly[[bis[µ6-4-(4-carboxylatophenoxy)benzene-1,3-dicarboxylato-κ6O1:O1:O3:O3':O4:O4']bis(1,10-phenanthroline-κ2N,N')tricobalt(II)] 0.72-hydrate], {[Co3(C15H7O7)2(C12H8N2)2]·0.72H2O}n, (I), is constructed from CoII ions and 4-(4-carboxyphenoxy)isophthalate (cpoia3-) and 1,10-phenanthroline (phen) ligands. Based on centrosymmetric trinuclear [Co3(phen)2(COO)6] secondary building units (SBUs), the structure of (I) is a three-dimensional CP with a (3,6)-connected net and point symbol (42.6)2(44.62.87.102). The positions of four [Co3(phen)2(COO)6] SBUs and four cpoia3- ligands reproduce a Chinese-knot-shaped arrangement along the ab plane. (I) has been characterized by single-crystal X-ray diffraction, IR spectroscopy, powder X-ray diffraction (PXRD) and thermostability analysis. It shows a good thermal stability from room temperature to 673 K. In addition, the temperature dependence of the magnetic properties was measured.

Irreversible solvent-assisted structural transformation in 3D metal-organic frameworks: Structural modification and enhanced iodine-adsorption properties.

In this work, we demonstrate a solvent-assisted structural transformation between two 3D metal-organic frameworks (MOFs) ([Zn4(α-bptc)2(H2O)3]n (1) → {[Zn2(α-bptc)(H2O)4]·(pra)}n (2)) (α-H4bptc = 2,3,3',4'-biphenyl tetra-carboxylic acid and pra = pyridin-2-amine) at room temperature by immersing complex 1 in a mother solution. The structural transformation involves not only solvent exchange but also the cleavage and formation of coordination bonds, which is confirmed by infrared spectroscopy, single-crystal X-ray diffraction analysis, powder X-ray diffraction patterns, and thermogravimetric analysis. Structural analyses revealed that significant modifications occurred during the transformation including the changes in lattice parameters, unit cell volume, space group, coordination number, secondary building units, and topological type. In the case of drastic structural transitions, significant changes in properties were also observed. Complex 2 displayed the interesting uptake and release of iodine with the changes in visible color, UV and fluorescence spectra, and fully reversible I2 uptake of 8.5 mg g-1, which further suggested about its future application as iodine absorbing material.

Acceptance of Chemo-prophylaxis for Latent Tuberculosis Infection among High School/College Student Contacts of Tuberculosis Patients in Shanghai, China.

Student contacts of tuberculosis (TB) cases are susceptible to latent tuberculosis infection (LTBI), and chemo-prophylaxis can reduce the risk of active TB among them. This study aimed to assess the acceptance of chemo-prophylaxis for LTBI among students, and their concerns regarding TB and its preventive treatment. A total of 560 students contacts were included in the investigation. The extent of contact was categorized from high to low (4 levels) with 12.9% of the students being close contacts. About 87.0% of the students were willing to receive chemo-prophylaxis if diagnosed with, LTBI, whereas 73 students declined. Students with a higher level of knowledge about TB (aOR = 1.11) or close contact with TB patients (aOR = 4.30) were more likely to accept treatment. To conclude, education regarding TB transmission is necessary. Moreover, LTBI detection should be integrated into the current school-based TB contact investigation.

A three-dimensional twofold interpenetrated cobalt(II) MOF containing a flexible carboxylate-based ligand: synthesis, structure and magnetic properties.

The design and synthesis of coordination polymers (CPs) have attracted much interest due to the intriguing diversity of their architectures and topologies. The functional solid catena-poly[µ2-aqua-triaqua{µ4-5-[4-carboxyphenoxy)methyl]benzene-1,3-dicarboxylato}{µ3-5-[4-carboxyphenoxy)methyl]benzene-1,3-dicarboxylato}dicobalt(II)], [Co2(C16H10O7)2(H2O)4]n or [Co2(HL)2(µ2-H2O)(H2O)3]n, was synthesized successfully by self-assembly of CoII ions with 5-[(4-carboxyphenoxy)methyl]isophthalic acid (H3L). The title compound was obtained under hydrothermal conditions and exhibits a twofold interpenetrated three-dimensional skeleton with hms 3,5-conn topology according to the cluster representation for valence-bonded metal-organic frameworks (MOFs). It has been characterized by single-crystal X-ray diffraction, IR spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analysis and susceptibility measurements. The antiferromagnetic coupling between adjacent CoII centres occurs via superexchange through the ligands.

Synthesis, crystal structure and characterization of a three-dimensional CdII coordination polymer constructed from 2,5-bis(1H-1,2,4-triazol-1-yl)terephthalate.

Bifunctional organic ligands are very popular for the design of coordination polymers because they allow the formation of a great diversity of structures. In the title coordination polymer, the new bifunctional inversion-symmetric ligand 2,5-bis(1H-1,2,4-triazol-1-yl)terephthalic acid (abbreviated as H2bttpa) links CdII cations, giving rise to the three-dimensional CdII coordination polymer catena-poly[diaqua[µ4-2,5-bis(1H-1,2,4-triazol-1-yl)terephthalato-κ4O1:O4:N4:N4']cadmium(II)], [Cd(C12H6N6O4)(H2O)2]n or [Cd(bttpa)(H2O)2]n. The asymmetric unit consists of half a CdII cation, half a bttpa2- ligand and one coordinated water molecule. The CdII cation is located on a twofold axis and is hexacoordinated in a distorted octahedral environment of four O and two N atoms. Four different bttpa2- ligands contribute to this coordination, with two carboxylate O atoms in trans positions and two triazole N atoms in cis positions. Two aqua ligands in cis positions complete the coordination sphere. The fully deprotonated bttpa2- ligand sits about a crystallographic centre of inversion and links two CdII cations to form a chain in a µ2-terephthalato-κ2O1:O4 bridge. This chain extends in the other two directions via the triazole heterocycles, producing a three-dimensional framework. O-H...O hydrogen bonds and weak C-H...N interactions stabilize the three-dimensional crystal structure. The FT-IR spectrum, X-ray powder pattern, thermogravimetric behaviour and solid-state photoluminescence of the title polymer have been investigated. The photoluminescence is enhanced and red-shifted with respect to the uncoordinated ligand.

Magnetic surface molecularly imprinted poly(3-aminophenylboronic acid) for selective capture and determination of diethylstilbestrol.

Diethylstilbestrol (DES) is considered a representative example of an exogenous endocrine disrupting compound (EDC). It can retard development in infants, lead to serious metabolic regulation disorders, and even result in distortion and cancer in the reproductive system. Therefore, achieving rapid and accurate analysis of trace amounts of DES in complex environments is of great importance to human health and for environmental protection. Novel magnetic molecularly imprinted polymers (MIPs) with excellent molecular recognition ability and super water-compatibility were developed for the selective capture of DES in water samples. Fe3O4@SiO2 magnetic nanoparticles (NPs) were synthesized and used as support cores. Molecularly imprinted poly(3-aminophenylboronic acid) (poly(APBA)), synthesized on magnetic cores based on a surface-imprinting strategy, can preferentially bind DES molecules in water samples. The magnetic core-shell MIPs (denoted as Fe3O4@SiO2@APBA/MIPs) exhibited high binding capacity and favorable recognition specificity for DES in water. The adsorption kinetics and experimental isotherm data of DES on magnetic MIPs can be well described by the pseudo-second-order kinetic model and the Langmuir isotherm, respectively. The imprinted nanoparticles were subjected to magnetic solid-phase extraction (MSPE) of DES from water samples. The DES content in the samples was determined by high-performance liquid chromatography (HPLC). The peak area increased linearly with increasing DES concentration over the range 0.08-150 µg L-1, with a detection limit of 0.03 µg L-1. The recoveries for spiked lake water samples were in the range 97.1-103.2%, with relative standard deviation (RSD) of 2.8-4.3% (n = 6).

Serum bile acid level and fatty acid composition in Chinese children with non-alcoholic fatty liver disease.

OBJECTIVE: To determine serum bile acid (BA) and fatty acid (FA) profiles in Chinese children with non-alcoholic fatty liver disease (NAFLD). METHODS: A total 76 children aged 4-17 years were categorized into three groups according to the presence and absence of as well as the severity of NAFLD, that is, non-NAFLD (control), mild and moderate to severe NAFLD groups, respectively, based on their liver ultrasonography findings. Serum BA and FA profiles were quantified separately by mass spectrometry and gas chromatography. General linear models were performed to assess the differences among the groups. RESULTS: After adjusted for potential confounders, children with NAFLD had higher levels of chenodeoxycholic acid (CDCA), unconjugated primary BAs (CDCA + cholic acid) but lower levels of deoxycholic acid (DCA), taurodeoxycholic acid (TDCA), glycodeoxycholic acid (GDCA), total DCA (DCA + TDCA + GDCA), glycolithocholic acid (GLCA) and total lithocholic acid (GLCA + taurolithocholic acid) than children without NAFLD. As for FAs, children with mild and moderate to severe NAFLD had higher levels of n-7 monounsaturated FA. CONCLUSIONS: Circulating BA and FA profiles may change in children with NAFLD. Further studies are needed to determine their associations and to understand the underlying mechanism of action.

Highly sensitive aptasensor based on synergetic catalysis activity of MoS2-Au-HE composite using cDNA-Au-GOD for signal amplification.

Single or few-layer nanosheets of MoS2 (MoS2 nanosheets) and a composite composed of MoS2 nanosheets, Au nanoparticles (AuNPs) and hemin (HE) (denoted as MoS2-Au-HE) were prepared. The composites possessed high synergetic catalysis activity towards the electroreduction of hydrogen peroxide. Furthermore, glucose oxidase (GOD) and AuNPs were used as marker of the complementary DNA (cDNA) strand of kanamycin aptamer to prepare a conjugate (reffered as cDNA-Au-GOD) that was designed as the signal probe. Both cDNA-Au-GOD and MoS2-Au-HE were applied to fabricate aptasensor for kanamycin. MoS2-Au-HE acted as solid platform for kanamycin aptamer and signal transmitters. AuNPs were employed as the supporter of cDNA and GOD which catalyze dissolved oxygen to produce hydrogen peroxide in the presence of glucose. Then cathodic peak current of H2O2 was recorded by differential pulse voltammetry (DPV). The electrochemical reduction of H2O2 was catalyzed by MoS2-Au-HE that was modified onto the surface of a glassy carbon electrode (GCE). The cathodic peak current of H2O2 was highly linearly decreased with an increase of kanamycin concentrations from 1.0ng/L to 1.0×105ng/L, with a detection limit of 0.8ng/L. This aptasensor can be used to detect kanamycin in milk with high specificity, sensitivity and selectivity.

A two-dimensional mixed-valence Cu(II)/Cu(I) coordination polymer constructed from 2-(pyridin-3-yl)-1H-imidazole-4,5-dicarboxylate.

Coordination polymers are a thriving class of functional solid-state materials and there have been noticeable efforts and progress toward designing periodic functional structures with desired geometrical attributes and chemical properties for targeted applications. Self-assembly of metal ions and organic ligands is one of the most efficient and widely utilized methods for the construction of CPs under hydro(solvo)thermal conditions. 2-(Pyridin-3-yl)-1H-imidazole-4,5-dicarboxylate (HPIDC(2-)) has been proven to be an excellent multidentate ligand due to its multiple deprotonation and coordination modes. Crystals of poly[aquabis[µ3-5-carboxy-2-(pyridin-3-yl)-1H-imidazole-4-carboxylato-κ(5)N(1),O(5):N(3),O(4):N(2)]copper(II)dicopper(I)], [Cu(II)Cu(I)2(C10H5N3O4)2(H2O)]n, (I), were obtained from 2-(pyridin-3-yl)-1H-imidazole-4,5-dicarboxylic acid (H3PIDC) and copper(II) chloride under hydrothermal conditions. The asymmetric unit consists of one independent Cu(II) ion, two Cu(I) ions, two HPIDC(2-) ligands and one coordinated water molecule. The Cu(II) centre displays a square-pyramidal geometry (CuN2O3), with two N,O-chelating HPIDC(2-) ligands occupying the basal plane in a trans geometry and one O atom from a coordinated water molecule in the axial position. The Cu(I) atoms adopt three-coordinated Y-shaped coordinations. In each [CuN2O] unit, deprotonated HPIDC(2-) acts as an N,O-chelating ligand, and a symmetry-equivalent HPIDC(2-) ligand acts as an N-atom donor via the pyridine group. The HPIDC(2-) ligands in the polymer serve as T-shaped 3-connectors and adopt a µ3-κ(2)N,O:κ(2)N',O':κN''-coordination mode, linking one Cu(II) and two Cu(I) cations. The Cu cations are arranged in one-dimensional -Cu1-Cu2-Cu3- chains along the [001] direction. Further crosslinking of these chains by HPIDC(2-) ligands along the b axis in a -Cu2-HPIDC(2-)-Cu3-HPIDC(2-)-Cu1- sequence results in a two-dimensional polymer in the (100) plane. The resulting (2,3)-connected net has a (12(3))2(12)3 topology. Powder X-ray diffraction confirmed the phase purity for (I), and susceptibilty measurements indicated a very weak ferromagnetic behaviour. A thermogravimetric analysis shows the loss of the apical aqua ligand before decomposition of the title compound.