N-octylpyridine hydrogen sulphate ionic liquid for multifunctional fluorescent response in different solvents.

Ionic liquids (ILs) have attracted considerable interest in the last two decades owing to their unique fluorescent properties. Herein, N-octylpyridine hydrogen sulphate ([OP]HSO4) was synthesised and characterised using 1H NMR and infrared spectroscopies. In addition, the fluorescence spectra of [OP]HSO4 in water, methanol, ethanol and acetonitrile were studied. In a single solvent, as the concentration of the solvent (methanol, ethanol or acetonitrile) increases, the fluorescence intensity of the IL first increases and then decreases. A similar trend was observed in their mixed solvents with water. Moreover, the fluorescence intensity of [OP]HSO4 decreases with increasing temperature. A fluorescence intensity reduction of only 4.46% for [OP]HSO4 after continuous scanning for 40 cycles under the maximum excitation state was analysed. The lack of photobleaching observed in [OP]HSO4 indicates its good photobleaching resistance.

Effects of acupuncture on microglial polarization and the TLR4/TRIF/MyD88 pathway in a rat model of traumatic brain injury.

OBJECTIVE: Neuroinflammation caused by traumatic brain injury (TBI) can lead to neurological deficits. Acupuncture can inhibit neuroinflammation and promote nerve repair; however, the specific mechanism is still unclear. The purpose of this study was to explore whether acupuncture could modulate the M1 and M2 phenotypic polarization of microglia in a rat model of TBI via the toll-like receptor 4 (TLR4)/intracellular toll-interleukin-1 receptor (TIR) domain-containing adaptor inducing interferon-ß (TRIF)/myeloid differentiation factor 88 (MyD88) pathway. METHODS: A total of 90 adult male Sprague-Dawley (SD) rats, SPF grade, were randomly divided into a normal group, model group and acupuncture group. Each group was further divided into three subgroups (first, third, and fifth day groups) according to the treatment time (n = 10 rats/subgroup). We used the modified neurological severity score (mNSS) method to quantify neurological deficits before and after modeling. We used Nissl staining to observe the pathological changes in brain tissue, flow cytometry to detect the proportion of M1 and M2 polarized microglia in the injured area on the first, third and fifth day, and co-immunoprecipitation (Co-IP) to examine TLR4/TRIF/MyD88 expression in microglia on the first, third and fifth day, as well as expression of the amount of binding of TLR4 with TRIF and MyD88. RESULTS: Compared to the model group, mNSS in the acupuncture group gradually decreased and pathological morphology improved. The proportion of CD11b/CD86 positive cells was decreased, while that of CD11b/CD206 was increased in the acupuncture group. Expression of IP TLR4, IP TRIF and IP MyD88 also decreased in the acupuncture group. CONCLUSION: The results of this study demonstrate that one of the mechanisms through which acupuncture mitigates neuroinflammation and promotes nerve repair in TBI rats may be inhibition of M1 phenotypic polarization and promotion of M2 phenotypic polarization through inhibition of the TLR4/TRIF/MyD88 signaling pathway.

A Stable Polyoxometalate-Based Metal-Organic Framework with Active CoMoO4 Layers for Electroreduction and Visible-Light-Driven Water Oxidation.

Polyoxometalate-based MOFs afford a great opportunity in terms of water oxidation. Herein, a new PMOF (SYNU-1) has been constructed with active CoMoO4 layers and TPPE ligands. In SYNU-1, each TPPE ligand bridges eight Co(II) and Mo(VI) cations to give a 3D (3,4,5)-connected (62·83·10)(63)(65·85) framework. SYNU-1 CPE exhibits electroreduction toward nitrite and bromate. Furthermore, SYNU-1 catalyst demonstrates electrocatalytic OER activity with a low overpotential of 364 mV. Strikingly, the heterogeneous catalyst SYNU-1 shows a high O2 yield (79.05%) for visible light water oxidation with good stability and reusability.

One-dimensional co-crystallized coordination polymers showing reversible mechanochromic luminescence: cation-anion interaction directed rapid self-recovery.

Three one-dimensional (1D) chain polymers (1D-9HAC, 1D-Cd-9AC, and 1D-Cd-9AC-HBIM) that exhibit different intermolecular interactions and stacking patterns have been designed and synthesized. Only 1D-Cd-9AC-HBIM with rigid (anion) and flexible (cation) units alternately arranged exhibits mechanochromic luminescence, which can be recovered through rapid solvent treatment or a self-recovery process.

Three resorcin[4]arene-based lanthanide-coordination polymers with multifunctional photoluminescence sensing properties.

By utilizing a novel octacarboxylate-functionalized resorcin[4]arene as organic linkers, three lanthanide-coordination polymers, namely, [(CH3)2NH2][Ln2(HL)(H2O)7]·2H2O (Ln = Tb (1), Eu (2) and Gd (3), H8L = 2,8,14,20-tetra-pentyl-4,6,10,12,16,18,22,24-octa-carboxymethoxy-resorcin[4]arene) have been solvothermally synthesized and structurally characterized. Isostructural 1-3 display unique two dimensional sandwich-based layers built with Ln3+ cations and bowl-shaped HL7- anions. Remarkably, 1 and 2 produce intensive green and red emissions respectively and long lifetimes thanks to the antenna effect of HL7- anions. The energy level testing of 3 indicates that the newly designed ligand H8L has a very efficient intersystem crossing process. More importantly, luminescent investigations reveal that 1 and 2 can selectively detect N,N'-dimethylformamide and Fe3+ ions with turn-on-type and turn-off-type responses, respectively.

Stereochemically Dependent Synthesis of Two Cu(I) Cluster-Based Coordination Polymers with Thermochromic Luminescence.

Two Cu(I) cluster based coordination polymers, [CuI(cis-bpype)]·CH3CN (1) and [Cu4I4(cis-bpype)3(trans-bpype)]·3DMF (2), have been synthesized from cis- and trans-1,2-bis(4-(pyridin-2-yl)phenyl)ethane (cis- and trans-bpype) ligands and {Cu4I4(PPh3)4} as starting materials. In compound 1, adjacent rhomboid-type {Cu2I2} units from the decomposition of {Cu4I4(PPh3)4} starting material connect by cis-bpype ligands to form a 1D framework. Compound 2 also has a 1D structure, but it has a {M2L3}-type coordinated cage constructed by three cis-bpype ligands and two {Cu4I4} secondary building units (SBU), and these coordination cages further link by trans-bpype to form the final frameworks. Upon cooling from 300 to 80 K, these Cu(I) cluster based coordination polymers exhibit interesting thermochromic behavior. In particular, compound 2 gives a chromic process from green luminescence at room temperature to red luminescence at 80 K and its corresponding CIE coordinates shift from green (0.34, 0.43) at 300 K to red (0.46, 0.42) at 80 K, respectively. This red shift of 124 nm (516 to 640 nm) is large enough to ensure a color change visible to the naked eye, which can be potentially utilized as a temperature sensor with a wide range.

Two tetraphenylethene-containing coordination polymers for reversible mechanochromism.

Two fluorescent coordination polymers have been designed and synthesized from a tetraphenylethene (TPE) derivative. These polymers, which can be potentially utilized as mechanical sensors, exhibit reversible mechanochromic luminescence with color changes visible to the naked-eye from blue to green-yellow by grinding or soaking in N,N-dimethylformamide (DMF) under UV irradiation.

PEG-Induced Synthesis of Coordination-Polymer Isomers with Tunable Architectures and Iodine Capture.

Controllable synthesis of coordination polymer (CP) isomers and revealing their structure-property relationships remain enormous challenges. Three new supramolecular isomers have been synthesized by tuning the poly(ethylene glycol) (PEG) content in the feed. These supramolecular isomers have the same framework formula of [Cu2 I2 (tppe)] and different architectures from the classical 2D stacking framework to a 3D entangled system with the coexistence of interpenetration and polycatenation, and a 3D topological framework. Interestingly, these CPs could be utilized for capturing iodine molecules. According to multiple complementary experiments and crystallographic analyses, iodine capture is mainly based on halogen-bond interactions in the inorganic {Cu2 I2 } building blocks of the framework. The present study describes a structure-property relationship in supramolecular isomerism with distinct topological structures.

Fluorescent Aromatic Tag-Functionalized MOFs for Highly Selective Sensing of Metal Ions and Small Organic Molecules.

By varying the fluorescent tags of resorcin[4]arene-based tetracarboxylic acids from phenyl to naphthyl, two highly luminescent metal-organic frameworks (MOFs), namely, [Zn2(TPC4A)(DMF)(H2O)4]·3H2O (1) and [(CH3)2NH2]2[Zn(TNC4A)]·4H2O (2), were successfully achieved (TPC4A = 2,8,14,20-tetra-phenyl-6,12,18,24-tetra-methoxy-4,10,16,22-tetra-carboxy-methoxy-resorcin[4]arene and TNC4A = 2,8,14,20-tetra-1-naphthal-6,12,18,24-tetra- methoxy-4,10,16,22-tetra-carboxy-methoxy-resorcin[4]arene). Compound 1 features a unique 2D network, while 2 exhibits a fascinating 3D framework. The highly selective detection of small organic molecules as well as Fe(2+) and Fe(3+) was performed for 1 and 2 as fluorescent sensors. Remarkably, luminescent 1 and 2 were used as sensory materials for the sensing of various amine vapors with high selectivity and rapid response. Most strikingly, clear fluorescence "on-off" switch-functions toward small organic molecules as well as amine vapors were also explored for luminescent 1 and 2.

Analyzing the promoters of two CYP9A genes in the silkworm Bombyx mori by dual-luciferase reporter assay.

Cytochrome P450s (CYPs) are widespread proteins that interact with exogenous chemicals from the diet or the environment. CYP9A subfamily genes are important in the silkworm Bombyx mori. We previously reported transcriptional levels of two CYP9A genes in different tissues and their responses to sodium fluoride (NaF). In this study, promoter truncation analysis using a dual-luciferase reporter assay in B. mori ovary cells (BmN) showed that the regions -1,496 to -1,102 bp for CYP9A19, and -1,630 to -1,210 bp for CYP9A22 were essential for basal transcriptional activity. Sequence analysis of these regions revealed several transcriptional regulatory elements but no typical promoter elements. Promoter activities were regulated after NaF induction and with an obvious dose effect. Although the dual-luciferase assay has been widely used to determine the activity of a given promoter in cell lines, problems with it still exist. Our results indicate that both plasmid size and construct protocols affect the experimental results.

ROS-Ca(2+) is associated with mitochondria permeability transition pore involved in surfactin-induced MCF-7 cells apoptosis.

The surfactin can inhibit proliferation and induce apoptosis in cancer cells. Moreover, surfactin can induce cell death in human breast cancer MCF-7 cells through mitochondrial pathway. However, the molecular mechanism involved in this pathway remains to be elucidated. Here, the reactive oxygen species (ROS) and Ca(2+) on mitochondria permeability transition pore (MPTP) activity, and MCF-7 cell apoptosis which induced by surfactin were investigated. It is found that surfactin evoked mitochondrial ROS generation, and the surfactin-induced cell death was prevented by N-acetylcysteine (NAC, an inhibitor of ROS). An increasing cytoplasmic Ca(2+) concentration was detected in surfactin-induced MCF-7 apoptosis, which was inhibited by 1,2-bis (2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid (BAPTA-AM, a chelator of calcium). In addition, the relationship between ROS generation and the increase of cytoplasm Ca(2+) was determined. The results showed that surfactin initially induced the ROS formation, leading to the MPTP opening accompanied with the collapse of mitochondrial membrane potential (ΔΨ(m)). Then the cytoplasmic Ca(2+) concentration increased in virtue of the changes of mitochondrial permeability, which was prevented by BAPTA-AM. Besides, cytochrome c (cyt c) was released from mitochondria to cytoplasm through the MPTP and activated caspase-9, eventually induced apoptosis. In summary, surfactin has notable anti-tumor effect on MCF-7 cells, however, there was no obvious cytotoxicity on normal cells.