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The application of iron oxide quantum dots (IOQDs) in this study led to the development of a straightforward, easy, and selective approach for cytosine sensing. To examine the capability of IOQDs in detecting nucleobases, attempts have been made to gain insight into the characteristics of IOQDs, including UV/Vis spectroscopic analysis, infrared spectroscopy, fluorescence spectroscopy, transmission electron microscopy, and powder‐XRD. We introduced IOQDs with a mean particle size distribution of 5.71 ± 0.08 nm for detecting cytosine by harnessing a turn‐on fluorescence phenomenon. The fostering fluorescence response of IOQDs was triggered in the presence of cytosine. In comparison, the presence of other nucleobases did not further induce the fluorescence signal of IOQDs. It was concluded that the hydrogen bonding bridging the carboxylate and hydroxyl groups on the surface of QDs with the amine groups of cytosine results in the elevation of IOQDs fluorescence. [ABSTRACT FROM AUTHOR]

Polyphyllin G, a pennogenyl saponin extracted from Paris polyphylla, has been shown to possess antitumor effects. In this study, we demonstrated that doxycycline, an antibiotic medicine, could significantly enhance the sensitivities of osteosarcoma cell lines to polyphyllin G. As the cells were pretreated with doxycycline at non‐toxic concentrations and then co‐exposed to polyphyllin G, this combination could induce a rapid cell death distinct from apoptosis. The non‐apoptotic cell death was characterized by a loss of integrity of plasma membrane without externalization of phosphatidyl serine. Furthermore, this combined treatment resulted in suppression of cell viability and colony‐forming ability, and increased the level of γ‐H2A.X, a critical marker for DNA damage, in osteosarcoma cell lines. When examining the underlying mechanism, it was revealed combination of polyphyllin G and doxycycline triggered an enhanced generation of reactive oxygen species (ROS), and up‐regulated mitochondrial oxidative stress within 0.5 h. Co‐administration of the ROS inhibitor NAC reversed the suppressed cell viability and colony‐forming ability, and abolished the increased level of γ‐H2A.X in the cells with the combined treatment, indicating that the enhanced ROS was involved in the anti‐proliferative effect of the combined treatment. Overall, the results demonstrated that doxycycline may function as chemosensitizers by inducing an acute and lethal ROS production to enhance cytotoxic of polyphyllin G in osteosarcoma cell lines, and the combined use of drugs may provide an alternative thinking for the development of new therapeutic agents. [ABSTRACT FROM AUTHOR]

In this study, guaiacolate derivatives‐containing tetranuclear sodium catalysts were synthesized, and their catalytic activity in l‐lactide (LA) polymerization was evaluated. Using LBF‐Na (sodium complex bearing 2,3‐dihydro‐2,2‐dimethyl‐7‐benzofuranolate) as a catalyst, the polymerization of LA was studied in various solvents. LBF‐Na polymerized LA in dichloromethane, tetrahydrofuran, and toluene, and the catalytic activity of LBF‐Na was similar in these solvents. Among the sodium complexes, LOH‐Na (sodium complex bearing guaiacolate) exhibited higher catalytic activity (5 min, conversion = 93%; MnGPC = 7200) than the other tetranuclear sodium complexes. Furthermore, LOH‐Na exhibited an "immortal" property after 20 equivalents of benzyl alcohol loading during LA polymerization and good controllability in polylactide production. Thus, guaiacolate ligands increase the catalytic activity of sodium catalysts in LA polymerization in both coordinating and halogen‐containing solvents and under the condition of extra alcohol loading. [ABSTRACT FROM AUTHOR]

Substantially to increase the efficiency of dye‐sensitized solar cells (DSSCs), it has been fabricated with the polymer gel electrolytes (PGEs) by replacing the liquid electrolytes (LEs). Poly (ε‐caprolactone) (PCL) has been synthesized as a crystalline solid biopolymer of about 74% yield using different 6‐membered ring phenolate Al complexes. As prepared PCL was blended with LE used in dye‐sensitized solar cells (DSSCs) to prepare high polydispersity index (PDI) PGE. The prepared PGE shows cross‐linking between carboxyl and hydroxyl groups and interacts with iodide ions to form a chelate complex structure. The PGE was well‐characterized using various analytical tools to demonstrate its structural and surface morphology. The fabricated DSSCs using PGE showed high ionic conductivity (7.76 × 10−4 S cm−1), good tri‐iodide diffusion (2.052 × 10−6 Cm2 S−1), and a highly stable incident photon‐to‐current conversion efficiency (PCE; 5.92%) under solar light illumination (85 mW cm−2). Besides found PGE has improved long‐term stability up to 15 days, and these results proved that the prepared PGE is superior compared to other reported PGEs. [ABSTRACT FROM AUTHOR]

Carbodicarbene (CDC), unique carbenic entities bearing two lone pairs of electrons are well‐known for their strong Lewis basicity. We demonstrate herein, upon introducing a weak Brønsted acid benzyl alcohol (BnOH) as a co‐modulator, CDC is remolded into a Frustrated Lewis Pair (FLP)‐like reactivity. DFT calculation and experimental evidence show BnOH loosely interacting with the binding pocket of CDC via H‐bonding and π‐π stacking. Four distinct reactions in nature were deployed to demonstrate the viability of proof‐of‐concept as synergistic FLP/Modulator (CDC/BnOH), demonstrating enhanced catalytic reactivity in cyclotrimerization of isocyanate, polymerization process for L‐lactide (LA), methyl methacrylate (MMA) and dehydrosilylation of alcohols. Importantly, the catalytic reactivity of carbodicarbene is uniquely distinct from conventional NHC which relies on only single chemical feature of nucleophilicity. This finding also provides a new spin in diversifying FLP reactivity with co‐modulator or co‐catalyst. [ABSTRACT FROM AUTHOR]

Aims/Introduction: To estimate preference‐based measures of health‐related quality of life associated with sociodemographic and clinical characteristics in type 2 diabetes patients. Materials and Methods: Individuals with EuroQol‐5 dimensions‐3 levels data were identified from Taiwan's National Health Interview Survey in 2009 and 2013. Status of diabetes, comorbidities, complications and treatments were ascertained through data linkage to Taiwan's National Health Insurance Research Database. Multivariable ordinary least squares, Tobit and median regression analyses were used to estimate the coefficients that represented independent impacts of patients' characteristics on health‐related quality of life. Results: The mean health utility score for 2,104 participants was 0.838. Being female, aging, divorced/widowed, never worked or underweight, or having a lower monthly household income, injectable glucose‐lowering therapy, comorbid connective tissue disease or depression were associated with lower health utilities. Having an amputation led to the largest reduction by 0.288 in health utilities, followed by debilitating stroke (0.266), heart failure (0.237), other coronary heart disease (0.185), kidney dialysis/transplant (0.148), coronary revascularizations (0.093), transient ischemic attack/stroke (0.078), diabetic neuropathy (0.062), polyneuropathy (0.055) and other neuropathy (0.043). Conclusions: Major vascular complications, connective tissue disease and depression are associated with considerably worse health‐related quality of life. These health utility estimates can facilitate health economic evaluations to determine cost‐effective strategies for diabetes management. [ABSTRACT FROM AUTHOR]

Three titanium (Ti) compounds bearing 2,6‐bis(o‐hydroxyalkyl)pyridine ligands were synthesized, and used in vitro cytotoxicity against triple‐negative breast cancer (TNBC) MDA‐MB‐231 cells was studied. The results of in vitro cytotoxicity of the complexes against TNBC cells revealed that (HLMeTi‐O)4 (IC50 = 0.91 μM) exerted a significant inhibitory effect on the proliferation of TNBC cells. Thus, titanium alkoxide complexes as nonplatinum complex could be used for structural optimization for treating breast cancer cells in the future. [ABSTRACT FROM AUTHOR]

Butein is a flavonoid isolated from various medicinal plants. It is known to have different biological activities including anti‐inflammation, anti‐adipogenesis, and anti‐angiogenesis. In the study, we demonstrated the anti‐proliferative effect of butein in human osteosarcoma U‐2 OS cells. Our data showed that butein significantly suppressed the viability and colony formation ability of U‐2 OS cells. Further experiments revealed butein exposure resulted in a cell cycle arrest at S and G2/M phase in U‐2 OS cells. Importantly, we found that butein activated the tumor suppressor p53, and trigged a p53‐dependent senescence in U‐2 OS cells. Knockdown of p53 suppressed the senescence and rescued the viability in butein‐treated U‐2 OS cells. Furthermore, we observed that butein exposure significantly enhanced reactive oxygen species (ROS) levels in U‐2 OS cells. Co‐administration of the ROS inhibitor NAC largely abolished the up‐regulated p53 protein level, and rescued the suppressed viability and colony formation ability in butein‐exposed U‐2 OS cells. Taken together, our data proposed the increased ROS by butein exposure activated p53, and the activated p53 was involved in the anti‐proliferative effect of butein via inducing senescence in U‐2 OS cells. This report suggests that butein is a promising candidate for cancer therapy against osteosarcoma. [ABSTRACT FROM AUTHOR]

Betulin is a lupane type pentacyclic triterpenoid, and commonly found in the bark of birch trees. It displays various pharmacological properties, such as antibacterial, anti‐inflammation, antitumor, and antiviral. In this report, we attempted to investigate the anti‐proliferative and pro‐apoptotic effects of betulin on osteosarcoma cell lines. Our results revealed that betulin significantly decreased cell viability and colony formation in osteosarcoma cell lines. Dose‐dependent induction of Annexin V positive cells, activated caspase 8, activated caspase 9, activated caspase 3, and the cleavage of poly (ADP‐ribose) polymerase were observed after the treatment with betulin, indicating betulin induces apoptosis in osteosarcoma cell lines. mTOR has been identified as a key modulator of autophagy in response to different stresses. In this study, we found that the treatment with betulin suppressed the activation of mTOR, and increased the level of LC 3‐II, the autophagy marker, in osteosarcoma cell lines. Co‐administration of the autophagy inhibitor chloroquine significantly rescued the cell viability and the clonogenic activity in betulin‐treated osteosarcoma cell lines. Our data showed that betulin induced autophagy, and the up‐regulated autophagy positively contributed to the apoptosis. Taken together, our findings suggested that betulin may serve as a promising anti‐proliferative agent for treating osteosarcoma. [ABSTRACT FROM AUTHOR]

A series of zinc complexes, [LXZnEt] (1–5) and [LXZn2(OAc)3] (6–9), associated with NNO‐tridentate Schiff base ligands (2‐(((2‐((cyclohexyl[methyl]amino)methyl)phenyl)imino)methyl)phenolate (CAP) derivatives), were synthesized, and their activity toward ring‐opening polymerization (ROP) of L‐lactide (LA) and the reaction of CO2 with cyclohexene oxide were also investigated. All of [LXZnEt] revealed excellent catalytic activity to ring‐opening polymerization (ROP) of LA in the presence of benzyl alcohol. Among them, [LHZnEt] (1) showed the highest activity with 82% conversation within 45 s. In contrast, [LXZn2(OAc)3] (6–9) were inactive in ROP of L‐lactide. In addition, all of these Zn complexes demonstrated moderate activity in the reaction of CO2 with cyclohexene oxide in the presence of Bu4NCl. [ABSTRACT FROM AUTHOR]

The palladacycle complex [LsPdOAc]2 bearing 2‐phenyl benzothiazole was synthesized and characterized by NMR and X‐ray crystallography. [LsPdOAc]2 was used as a catalyst in the Suzuki–Miyaura cross coupling reaction of 4‐bromotoluene with phenylboronic acid, which resulted in a conversion of >90% with 5 mol% of the Pd complex within 10 min at 60°C. The palladacycle complex [LsPdOAc]2 bearing 2‐phenyl benzothiazole was used as a catalyst in the Suzuki–Miyaura cross coupling reaction. In a case of 4‐bomotoluene and phenylboronic acid with Cs2CO3 as a base in a 1:1 mixture solvent (3 mL) of DMF + H2O at 60 °C after 10 min, the conversion is 90 %. [ABSTRACT FROM AUTHOR]

Treatment of known complex [Cp2Fe2 (μ-SEt)2(CH3CN)2](BF4) 2 (1(BF4) 2) with 2 equiv of 1,4-bis(isocyanomethyl)benzene (1,4-CNCH2C6H4CH2NC; L1) or 4,4'-diisocyanophenyl ether (4,4'-CNC6H4OC6H4NC; L2) result in the formation of two new-type diisocyanide complexes [Cp2Fe2 (μ-SEt)2(1,4-CNCH2C6H4CH2NC)2](BF4) 2 (2a(BF4) 2) or [Cp2Fe2 (μ-SEt)2(4,4'-CNC6H4OC6H4NC)2](BF4) 2(2b(BF4) 2), respectively. The new-type 24-membered ring tetranuclear iron-thiolate-aryldiisocyanide metallocyclophane complex [Cp4Fe4 (μ-SEt)4(μ-1,4-CNCH2C6H4CH2NC)2](BF4) 4 (3a(BF4) 4) has been synthesized by using a self-assembly reaction between equimolar amounts of 1(BF4) 2 and 1,4-bis(isocyanomethyl)benzene or by a stepwise route involving mixing a 1:1 molar ratio of complexes 1(BF4) 2 and 2a(BF4) 2. A similar approach was used through the application of equal molar ratio of complexes 1(BF4) 2 and 2b(BF4) 2 to give a 30-membered ring tetranuclear iron-thiolate-aryldiisocyanide metallocyclophane complex [Cp4Fe4 (μ-SEt)4(4,4'-CNC6H4OC6H4NC)2][BF4 ]4 (3b(BF4)4). The spectroscopic and electrochemical properties of four iron-sulfur core complexes were determined. [ABSTRACT FROM AUTHOR]

A series of bidentate ligands were examined to improve the catalytic activity of l-lactide ( LA) polymerization by using n-butyl lithium and BnOH. For LA polymerization, n-butyl lithium with tetraisopropyl methylenebis(phosphonate) ( L8 ) showed the greatest catalytic activity but with poor controllability of the polymer molecular weight. The polydispersity indices ( PDIs) could be improved without BnOH addition, but Mn GPC was much different from the Mn Cal . 1H NMR spectra confirmed that the cyclized PLA was obtained, thus implying that active chain-end mechanisms were operative in LA polymerization. [ABSTRACT FROM AUTHOR]

This study synthesized a series of titanium iminophenoxide complexes and investigated their suitability as catalysts for the ring-opening polymerization of L-lactide ( L-LA) and ε-caprolactone (CL). Complexes with bidentate ligands demonstrate higher catalytic activity than their tridentate counterparts since the third coordination atom needs to contend with L-LA and CL. Differences in the geometric framework of bidentate ligands also influence the catalytic activity. Type II ligands ( N, N-trans form of Ti complex) prevent the coordination of monomers to Ti thereby decreasing the initiation rate. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 [ABSTRACT FROM AUTHOR]

This study investigated the synthesis of the biocatalyst, magnesium 2,6-di- tert-butyl-4-methylphenoxide (Mg(BHT)2) complex, and the ring-opening polymerization (ROP) of ε-caprolactone (CL). The complex demonstrates high catalytic activity and controllable of molecular weight for the ROP of CL in tetrahydrofuran at room temperature, even when polymerization was performed under air. Before this study, the polymerization of CL had never been performed using a magnesium catalyst under air at room temperature. Various forms of alcohols with different purposes were also used as initiators with Mg(BHT)2. The results show that the magnesium complex acts as a perfect catalyst because of its high catalytic activity and control ability without any cytotoxicity in the polymerization of CL, making it suitable for biomedical applications. In addition, nanoparticle formation, cytotoxicity, and phototoxicity of tri-2-hydroxyethyl ester [Ce6-(CH2CH2OPCL)3] were also studied in this article and Ce6-(CH2CH2OPCL)3 formed nanoparticle can act as a nanophotosensitizer for photodynamic therapy. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

The monomeric title complex, [Zn(C14H12NOS)2]·2CHCl3 or L2Zn·2CHCl3, where L is the 2-({[2-(methyl-sulfan-yl)phen-yl]imino}-meth-yl)phenolate anion, may be obtained by the reaction of LZnEt with benzyl alcohol or by the reaction of two equivalents of LH with ZnEt2 in tetra-hydro-furan. The Zn atom, located on a twofold axis, is four-coordinated in a distorted tetra-hedral geometry by two O atoms [Zn-O = 1.9472 (19) Å] from the phenolate anions and two imine N atoms [Zn-N = 2.054 (2) Å].

In the title complex, [CaI(C(4)H(10)O(2))(3)]I, the Ca(II) atom is seven-coordinated by six O atoms from three 1,2-dimeth-oxy-ethane (DME) ligands and one iodide anion in a distorted penta-gonal-bipyramidal geometry. The I atom and one of the O atoms from a DME ligand lie in the axial positions while the other O atoms lie in the basal plane. The other iodide anion is outside the complex cation.