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Background: Systemic inflammation associated with sepsis can induce neuronal hyperexcitability, leading to enhanced seizure predisposition and occurrence. Brain microglia are rapidly activated in response to systemic inflammation and, in this activated state, release multiple cytokines and signaling factors that amplify the inflammatory response and increase neuronal excitability. NADPH oxidase (NOX) enzymes promote microglial activation through the generation of reactive oxygen species (ROS), such as superoxide anion. We hypothesized that NOX isoforms, particularly NOX2, are potential targets for prevention of sepsis-associated seizures., Methods: To reduce NADPH oxidase 2-derived ROS production, mice with deficits of NOX regulatory subunit/NOX2 organizer p47 phox (p47 phox-/- ) or NOX2 major subunit gp91 phox (gp91 phox-/- ) were used or the NOX2-selective inhibitor diphenyleneiodonium (DPI) was used to treat wild-type (WT) mice. Systemic inflammation was induced by intraperitoneal injection of lipopolysaccharide (LPS). Seizure susceptibility was compared among mouse groups in response to intraperitoneal injection of pentylenetetrazole (PTZ). Brain tissues were assayed for proinflammatory gene and protein expression, and immunofluorescence staining was used to estimate the proportion of activated microglia., Results: Increased susceptibility to PTZ-induced seizures following sepsis was significantly attenuated in gp91 phox-/- and p47 phox-/- mice compared with WT mice. Both gp91 phox-/- and p47 phox-/- mice exhibited reduced microglia activation and lower brain induction of multiple proconvulsive cytokines, including TNFα, IL-1β, IL-6, and CCL2, compared with WT mice. Administration of DPI following LPS injection significantly attenuated the increased susceptibility to PTZ-induced seizures and reduced both microglia activation and brain proconvulsive cytokine concentrations compared with vehicle-treated controls. DPI also inhibited the upregulation of gp91 phox transcripts following LPS injection., Conclusions: Our results indicate that NADPH oxidases contribute to the development of increased seizure susceptibility in mice after sepsis. Pharmacologic inhibition of NOX may be a promising therapeutic approach to reducing sepsis-associated neuroinflammation, neuronal hyperexcitability, and seizures.

Novel comb-shaped amphiphilic copolymers based on methoxy poly(ethylene glycol)-b-[poly(ε-caprolactone)-g-poly(methacrylic acid)] (MPCL-g-pMAA), were synthesized via ring opening polymerization (ROP) and atom transfer radical polymerization (ATRP) for drug delivery systems. MPCL-g-pMAAs with various MAA repeating units self-assemble into a core-shell structure in an aqueous solution. Critical aggregation concentrations range within 5.6×10 -3 -7.0×10 -2 mg/mL in double deionized water and 8.9×10 -3 -7.0×10 -2 mg/mL in phosphate buffered saline of pH 7.4, decreasing with increase in pMAA length. The carboxylic groups of MPCL-g-pMAAs were utilized to coordinate cisplatin, forming polymer-metal complexes for chemotherapy. The average hydrodynamic diameters of particles are within 220-246nm, slightly dependent on pMAA length. However, the cisplatin-loaded MPCL-g-pMAAs particles have average hydrodynamic diameters of 263-412nm owing to increasing drug loading efficiency with increase in pMAA length. Nevertheless, the MPCL-g-pMAA with the least number of MAA repeating unit shows the fastest drug release rate as well as the highest cytotoxicity against CRL-5802 cells. The cellular uptake of MPCL-g-pMAA particles, involving mainly clathrin-mediated endocytosis, increases with incubation time. MPCL-g-pMAA particles are non-cytotoxic to CRL-5802 cells but the cisplatin-loaded MPCL-g-pMAA particles show profound cell-killing ability. The MPCL-g-pMAA is a potential carrier for drug delivery systems., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Serum magnesium (Mg) levels are closely controlled through a variety of Mg transporters and ionic channels during physiological conditions. These levels have been shown to increase during exercise. However, the effect of Mg transporter expression during exercise remains to be determined. The purpose of this study was to examine the gene expression of SLC41A1, a Na + /Mg 2+ exchanger, during exercise. In the present study, male C57BL/6JNarl mice (n=16, 8 weeks old) were subjected to 3 h forced exercise on a treadmill. The mice in the control and Mg groups were injected with saline and Mg (MgSO 4 , 90 mg/kg, intraperitoneal), respectively. Blood samples were obtained at three time points: prior to, following and 24 h after exercise. The gene expression levels of SLC41A1 were significantly downregulated to 23.6±4.6 and 12.6±10.2% following exercise in the control and Mg groups, respectively. The expression levels returned to the basal levels 24 h after exercise in the two groups and there was no significant difference found between the two groups. The downregulated role of SLC41A1 expression and its interaction with the Mg status in exercise requires further investigation.

Two pentanuclear copper(I) thiolato clusters of the formula [Cu(5)(L)(3)](-) (L = pyridine-2,6-dimethanethiolate (L1), (1); 4-methylpyridine-2,6-dimethanethiolate (L2), (2)) were synthesized utilizing a single-step procedure, and their structures were characterized by X-ray crystallography. The aforementioned pentanuclear complexes possess an interesting propeller-like Cu(5)S(6) core where all Cu centers are three-coordinate. Electrospray ionization mass spectrometry (ESI-MS) investigation of the pentanuclear copper(I) thiolato clusters with added hetero-ligands demonstrated interesting ligand exchange behavior. The product distribution resulting from ligand exchange not only depended on the quantity of added ligand, but also was sensitive to the coordination ability of the ligand. The ESI-MS method used in this study can serve as a useful tool for probing exchange behavior in coordination metal complexes that cannot otherwise be determined by NMR., (Copyright © 2012 Elsevier Inc. All rights reserved.)

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.

The efficacy of many chemotherapeutic agents is reduced in cells that have developed multiple drug resistance (MDR). To address this important problem, a biodegradable polymer was coupled to a photosensitizer and the resulting photosensitizer-nanoparticles were loaded with the chemotherapeutic agent doxorubicin. The combination of photosensitizer and chemotherapeutic agent had a synergistic action on a doxorubicin-resistant breast cancer MCF-7 cell line. To increase the effectiveness of this combination, d-alpha-tocopheryl poly(ethylene glycol) 1000 succinate (TPGS), an inhibitor of the multidrug transporter overproduced in these resistant cells, was added during the formation of the nanoparticles. The insertion of TPGS decreased the P-glycoprotein activity, increased the intracellular accumulation doxorubicin, and also increased the therapeutic efficacy of the resulting nanoparticles. Both TPGS and irradiation of the photoreactive nanoparticles caused doxorubicin to move from the cytoplasm to the nucleus. This combination of photodynamic activity in a powerful nanocarrier loaded with the chemotherapeutic agent doxorubicin can be used to deliver two types of cancer therapy simultaneously, and the addition of TPGS can further enhance the entry of doxorubicin into the nucleus. Therefore, this innovative delivery system can act as a potential nanomedicine for both drug-sensitive and drug-resistant cancer therapy., (Copyright © 2011 Elsevier B.V. All rights reserved.)

A series of heterobimetallic titanium(IV) complexes [LTi(O(i)Pr)(mu-O(i)Pr)(2)Li(THF)(2)], [LTi(O(i)Pr)(mu-O(i)Pr)(2)Na(THF)(2)], [LTi(mu-O(i)Pr)(2)Zn(O(i)Pr)(2)], and [LTi(mu-O(i)Pr)(2)Mg(O(i)Pr)(2)] (where L = bidentate bisphenol ligands) have been synthesized and characterized including a structural determination of [L(1)Ti(mu(2)-O(i)Pr)(2)(O(i)Pr)Li(THF)(2)] (1a). These complexes were investigated for their utility in the ring-opening polymerization (ROP) of l-lactide (LA). Polymerization activities have been shown to correlate with the electronic properties of the substituent within the bisphenol ligand. In contrast to monometallic titanium initiator 1e, all the heterobimetallic titanium initiators (Ti-Li, Ti-Na, Ti-Zn, and Ti-Mg) show enhanced catalytic activity toward ring-opening polymerization (ROP) of l-LA. In addition, the use of electron-donating methoxy or methylphenylsulfonyl functional ligands reveals the highest activity. The bisphenol bimetallic complexes give rise to controlled ring-opening polymerization, as shown by the linear relationship between the percentage conversion and the number-average molecular weight. The polymerization kinetics using 2c as an initiator were also studied, and the experimental results indicate that the reaction rate is first-order with respect to both monomer and catalyst concentration with a polymerization rate constant, k = 81.64 M(-1) min(-1).

Photophysical properties such as absorption and emission spectra, lifetimes, and redox potentials of eight ruthenium complexes, Ru(LL)2(MebpyCOOH)2+, where LL represents bpy, phen, Me2bpy, Me4bpy, (MeO)2bpy, (EtO)2bpy, Cl2bpy, and NO2phen, have been measured. The acid dissociation constants of ground and excited states have been determined. The ground-state pKa values were obtained from the pH dependence of the complex absorbance changes. The excited-state pKa* values were extracted from the emission titration curve and corrected for the excited-state lifetime of both protonated and deprotonated species. The largest DeltapKa, pKa*-pKa, found for Ru(Me2bpy)2(MebpyCOOH)2+ and Ru(Me4bpy)2(MebpyCOOH)2+ of 1.7 indicate that MebpyCOOH gains most of the MLCT excited-state electron. The big negative DeltapKa found for Ru(Cl2bpy)2(MebpyCOOH)2+, -4.2, clearly indicates the metal-to-ligand charge transfer to the Cl2bpy ligands.