Synthesis and crystal structure of [Nd(eta(6)-1,3,5-C6H3Me3)(AlCl4)(3)]( C6H6) and structural comparison of Ln(eta(6)-arene)(AlCl4)(3)

Reaction of NdCl3, with AlCl3 and mesitylene in benzene gives complex [Nd(eta (6)-1,3,5-C6H3Me3) (AlCl4)(3)] (C6H6) (1) which was characterized by elemental analysis, IR spectra, MS and X-lay diffractions. The X-ray determination indicates that 1 has a distorted pentagonal bipyramidal geometry and crystallizes in the monoclinic, space group P2(1)/n with a = 0.9586(2), b = 1.1717(5), c = 2.8966(7) nm, beta = 90.85 (2)degrees, V = 3.2529(6) nm(3), D-c = 1.573 g/cm(3), Z = 4. A comparison of bond parameters for all the reported Ln(eta (6)-Ar) (AlCl4)(3) complexes indicates that the bond distance of Ln-C is shortened with the increasing of methyl group on benzene and with the decreasing of radius of lanthanide ions.

Synthesis and crystal structure of (1,3-(Bu2C5H3)-Bu-t)(2)Sm(mu-Cl)(2)Li(THF)(2)

Anhydrous SmCl3 reacts with two equal of Li(1-3-(Bu2C5H3)-Bu-t) to give a complex (1,3-(Bu2C5H3)-Bu-t)(2) Sm(mu -Cl)(2)Li(THF)(2) (C34H58Cl2LiO2Sm, M-r = 726.99), monoclinic, space group P2(1)/n, a = 10.615(2), b = 21.037(4), c = 17.166(3) Angstrom, beta = 93.60(3)degrees, V = 3825.7 (13) Angstrom (3), Z = 4, D-c = 1.262 Mg/m(3), mu = 1.699 mm(-1) and F(000) = 1508, final R = 0.0387 and wR = 0.0741 for 5320 observed[I greater than or equal to2 sigma (I)] reflections. The average Sm - C distance is 2.73 Angstrom. Sm - Cl1 and Sm - Cl2 distances are 2.719 (2) and 2. 697 (2) Angstrom, respectively. Two 1, 3-(Bu2C5H3)-Bu-t-ring centroids and two mu (2)-bridging chloride atoms around Sm atom form a distorted tetrahedron.

STUDIES ON OLEFIN-COORDINATING TRANSITION-METAL CARBENE COMPLEXES .20. SYNTHESIS OF 1,3-CYCLOHEXADIENE(DICARBONYL) [ETHOXY(ARYL)-CARBENE]IRON COMPLEXES AND THEIR PHOSPHINE ADDUCTS - CRYSTAL-STRUCTURE OF C6H8(CO)2FEC(OC2H5)C6H4CH3-O

Reaction of 1,3-cyclohexadiene(tricarbonyl)iron (1) with ortho-substituted aryllithium reagents ArLi (Ar=o-CH3C6H4, o-CH3OC6H4, o-CF3C6H4) in ether at low temperature, and subsequent alkylation of the acylmetalates formed with Et3OBF4 in aqueous solution at 0-degrees-C or in CH2Cl2 at -60-degrees-C gave the 1,3-cyclohexadiene(dicarbonyl)[ethoxy(aryl)carbene]iron complexes (eta4-C6H8)(CO)2FeC(OC2H5)Ar (3, Ar = o-CH3C6H4; 4, Ar = o-CH3OC6H4), and the isomerized product (eta3-C6H8)(CO)2FeC(OC2H5)C6H4CF3-o (5), respectively, among which the structure of 3 has been established by an X-ray diffraction study. Complex 3 is monoclinic, space group P2(1) with a = 8.118(4), b = 7.367(4), c = 14.002(6) angstrom, beta = 104.09(3)-degrees, V = 812.2(6) angstrom3, Z = 2, D(c) = 1.39 g cm-3, R = 0.056, and R(w) = 0.062 for 976 observed reflections. Complexes 3 and 5 were converted into the chelated allyliron phosphine adducts(eta3-C6H8)(CO)2(PR31)FeC(OC2H5)Ar (6, Ar = o-CH3C6H4, R1 = Ph; 7, Ar = o-CH3C6H4, R1 = OPh; 9, Ar = o-CF3C6H4, R1 = Ph), by reaction with phosphines in petroleum ether at low temperatures.

STRUCTURE OF 1,3-PROPANEDIAMMONIUM TETRACHLOROCOBALTATE(II)

[CoCl4(C3H12N2)], M(r) = 276.87, monoclinic, P2(1)/n, a = 10.703 (2), b = 10.653 (1), c = 10.852 (2) angstrom, beta = 118.46 (1)-degrees, V = 1087.8 angstrom 3, Z = 4, D(x) = 1.69 g cm-3, lambda(Mo K-alpha) = 0.71073 angstrom, mu = 22.60 cm-1, F(000) = 556, T = 298 K, final R = 0.059 for 1068 unique reflections [I > 3-sigma(I)]. The Co(II) ion is coordinated by four Cl atoms in a tetrahedral geometry. The paraffinic chains which bridge the tetrahedra have a nearly planar zigzag configuration.

Cell surface beta 1, 4-galactosyltransferase 1 promotes apoptosis by inhibiting epidermal growth factor receptor pathway.

Our previous studies have shown that overexpression of beta1,4-galactosyltransferase1 (beta1,4GT1) leads to increased apoptosis induced by cycloheximide (CHX) in SMMC-7721 human hepatocarcinoma cells. However, the role of beta1,4GT1 in apoptosis remains unclear. Here we demonstrated that cell surface beta1,4GT1 inhibited the autophosphorylation of epidermal growth factor receptor (EGFR) especially at Try 1068. The phosphorylation of protein kinase B (PKB/Akt) and extracellular signal-regulated protein kinase1/2 (ERK1/2), which are downstream molecules of EGFR, were also reduced in cell surface beta1,4GT1-overexpressing cells. Furthermore, the translocations of Bad and Bax that are regulated by PKB/Akt and ERK1/2 were also increased in these cells. As a result, the release of cytochrome c from mitochondria to cytosol was increased and caspase-3 was activated. In contrast, RNAi-mediated knockdown of beta1,4GT1 increased the autophosphorylation of EGFR. These results demonstrated that cell surface beta1,4GT1 may negatively regulate cell survival possibly through inhibiting and modulating EGFR signaling pathway.

The beta-(1--

The stimulatory effects of the synthetic beta-(1-->6)-branched beta-(1-->3) glucohexaose and its analogues containing an alpha-(1-->3)-linked bond on the mouse spleen were studied for elucidation of the mechanism of their antitumor activity, and their stimulatory effects were compared with Lentinan. The mouse spleen's weight was increased after the intraperitoneal (i.p.) injection of the oligosaccharides compared with the saline group. In addition, routinely hematoxylin and eosin (HE)-stained spleen sections showed that the injection also changed the spleen's histopathology. RNA samples were isolated from splenocytes of oligosaccharides, Lentinan or saline-injected mice. Reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot showed that the administration of the oligosaccharides or Lentinan enhanced mouse spleen mRNA production of TNF-alpha but not IL-2. The injection also enhanced Concanavalin A (Con A)-induced mouse splenocytes proliferation, but the in vitro administration of the oligosaccharides did not have the proliferation-enhancing effect. Taken together, these results suggest that the synthetic beta-(1-->6)-branched beta-(1-->3) glucohexaose and its analogues containing an alpha-(1-->3)-linked bond have similar stimulatory effects as Lentinan. Additionally, they may exert their antitumor effects through the induction of splenocytes mediated immune responses.

Glucose solvation by the ionic liquid 1,3-dimethylimidazolium chloride: A simulation study

Simulations of beta-glucose in the ionic liquid 1,3-dimethylimidazoliurn chloride have been performed in order to examine the solvation environment of the carbohydrate. Both single molecule and 1:5 glucose:ionic liquid (16.7 wt %) solutions are Studied, and the hydrogen bonding between sugar and solvent is examined. The primary solvation shell around the perimeter of the glucose ring consists predominantly of chloride anions which hydrogen bond to the hydroxyl groups. A small presence of the cation is also found, with the association Occurring through the weakly acidic hydrogen at the 2-position of the imidazolium ring interacting with the oxygen atoms of the sugar secondary hydroxyls. An average chloride coordination number of 4 is found around the glucose for both the single molecule and high concentration Simulations, despite the reduced chloride:glucose ratio in the latter case. In relation to the cation, the glucose molecules occupy positions above and below the plane of the imidazolium ring. Importantly, even at high glucose concentrations, no significant change in the anion-cation interactions and overall liquid structure of the ionic liquid is found, indicating that the glucose is readily accommodated by the solvent at this concentration. Dominant contributions to the sugar-ionic liquid interaction energy come from favorable hydrogen bonding (electrostatic) interactions between hydroxyls and chlorides, although a small favorable van der Waals energy contribution is also seen between the sugar and cations suggesting that the cation could be tailored in order to further improve the dissolution of glucose/cellulose in ionic liquid systems.

Protein kinase B/Akt activity is involved in renal TGF-beta 1-driven epithelial-mesenchymal transition in vitro and in vivo

The molecular pathogenesis of diabetic nephropathy (DN), the leading cause of end-stage renal disease worldwide, is complex and not fully understood. Transforming growth factor-beta (TGF-beta1) plays a critical role in many fibrotic disorders, including DN. In this study, we report protein kinase B (PKB/Akt) activation as a downstream event contributing to the pathophysiology of DN. We investigated the potential of PKB/Akt to mediate the profibrotic bioactions of TGF-beta1 in kidney. Treatment of normal rat kidney epithelial cells (NRK52E) with TGF-beta1 resulted in activation of phosphatidylinositol 3-kinase (PI3K) and PKB/Akt as evidenced by increased Ser473 phosphorylation and GSK-3beta phosphorylation. TGF-beta1 also stimulated increased Smad3 phosphorylation in these cells, a response that was insensitive to inhibition of PI3K or PKB/Akt. NRK52E cells displayed a loss of zona occludins 1 and E-cadherin and a gain in vimentin and alpha-smooth muscle actin expression, consistent with the fibrotic actions of TGF-beta1. These effects were blocked with inhibitors of PI3K and PKB/Akt. Furthermore, overexpression of PTEN, the lipid phosphatase regulator of PKB/Akt activation, inhibited TGF-beta1-induced PKB/Akt activation. Interestingly, in the Goto-Kakizaki rat model of type 2 diabetes, we also detected increased phosphorylation of PKB/Akt and its downstream target, GSK-3beta, in the tubules, relative to that in control Wistar rats. Elevated Smad3 phosphorylation was also detected in kidney extracts from Goto-Kakizaki rats with chronic diabetes. Together, these data suggest that TGF-beta1-mediated PKB/Akt activation may be important in renal fibrosis during diabetic nephropathy.

The structure of [Co(H-tptz)Cl-3] center dot H2O (tptz=2,4,6-tri(2-pyridyl)-1,3,5-triazine) prepared by crystallization from the ionic liquid, N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide

The structure of tris-chloro[2,6-bis(2'-pyridyl)-4-(2'-pyridinium)-1,3,5-triazine]cobalt(II) monohydrate, [Co(C18H13N6)Cl-3]center dot H2O (C2/c (No. 15), a = 7.783(11), b = 22.42(3), c = 11.001(15) angstrom, beta = 90.05(2)degrees), crystallized from the open air reaction of CoCl2 and 2,4,6-tri(2-pyridyl)-1,3,5-triazine in the ionic liquid, N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide is reported. The structure consists of six coordinate cobalt in an octahedral geometry bonded to the tridentate tptz ligand and three chlorines. The non-coordinating pyridyl group in the tptz ligand is protonated (with the protonated nitrogen crystallographically disordered over two possible sites), providing overall charge neutrality for the complex.

Connective tissue growth factor antagonizes transforming growth factor-beta 1/Smad signalling in renal mesangial cells

The critical involvement of TGF-beta 1 (transforming growth factor-beta 1) in DN (diabetic nephropathy) is well established. However, the role of CTGF (connective tissue growth factor) in regulating the complex interplay of TGF-beta 1 signalling networks is poorly understood. The purpose of the present study was to investigate co-operative signalling between CTGF and TGF-beta 1 and its physiological significance. CTGF was determined to bind directly to the T beta RIII (TGF-beta type III receptor) and antagonize TGF-beta 1-induced Smad phosphorylation and transcriptional responses via its N-terminal half. Furthermore, TGF-beta 1 binding to its receptor was inhibited by CTGF. A consequent shift towards non-canonical TGF-beta 1 signalling and expression of a unique profile of differentially regulated genes was observed in CTGF/TGF-beta 1-treated mesangial cells. Decreased levels of Smad2/3 phosphorylation were evident in STZ (streptozotocin)-induced diabetic mice, concomitant with increased levels of CTGF Knockdown of T beta RIII restored TGF-beta 1-mediated Smad signalling and cell contractility, suggesting that T beta RIII is key for CTGF-mediated regulation of TGF-beta 1. Comparison of gene expression profiles from CTGF/TGF-beta 1-treated mesangial cells and human renal biopsy material with histological diagnosis of DN revealed significant correlation among gene clusters. In summary, mesangial cell responses to TGF-beta 1 are regulated by cross-talk with CTGF, emphasizing the potential utility of targeting CTGF in DN.

Novel anti-inflammatory compound SEN1176 alleviates behavioural deficits induced following bilateral intrahippocampal injection of aggregated amyloid-beta(1-42).

Behavioral effects of a novel anti-inflammatory SEN1176 were investigated. This pyrrolo[3,2-e][1,2,4]triazolo[1,5-a]pyrimidine suppresses amyloid-ß (Aß)1-42-induced macrophage production of nitric oxide, TNF-a, IL-1ß, and IL-6 in a dose-dependent fashion, an activity profile consistent with SEN1176 being a neuroinflammation inhibitor. Using male Sprague-Dawley rats, SEN1176 was examined relative to detrimental behavioral effects induced following bilateral intrahippocampal (IH) injections of aggregated Aß1-42. The rats were trained to respond under an alternating-lever cyclic-ratio (ALCR) schedule of food reinforcement, enabling measurement of parameters of operant performance that reflect aspects of learning and memory. Under the ALCR schedule, orally administered SEN1176 at 5, 20, or 30 mg/kg was effective in reducing the behavioral deficit caused by bilateral IH aggregated Aß1-42 injections in a dose-related manner over a 90-day treatment period. SEN1176 at 20 and 30 mg/kg significantly reduced lever switching errors and, at doses of 5, 10, and 30 mg/kg, significantly reduced incorrect lever perseverations, indicating a reduction of the behavioral deficit induced as a result of inflammation following IH Aß1-42 injections. When treatment with SEN1176 was instigated 30 days after IH Aß1-42 injections, it resulted in progressive protection, and withdrawal of SEN1176 treatment 60 days after IH Aß1-42 injections revealed partial retention of the protective effect. SEN1176 also significantly reduced numbers of activated astrocytes adjacent to the aggregated Aß1-42 injection sites. These results indicate the potential of SEN1176 for alleviating chronic neuroinflammatory processes related to brain Aß deposition that affect learning and memory in Alzheimer's disease.

High-performance liquid chromatographic determination of 17 beta-estradiol and 17 beta-estradiol-3-acetate solubilities and diffusion coefficients in silicone elastomeric intravaginal rings

A rapid, sensitive reversed-phase high-performance liquid chromatographic method has been developed for the determination of in vitro release of 17 beta-estradiol and its ester prodrug, 17 beta-estradiol-3-acetate, from silicone intravaginal rings. Partial hydrolysis of the acetate under the aqueous conditions provided by the 1% benzalkonium chloride release medium necessitates its conversion to 17 beta-estradiol prior to HPLC analysis. Both steroid peaks have been fully resolved from the benzalkonium chloride peaks by the reported chromatographic method,which employs a C-18 bonded reversed-phase column, an acetonitrile-water (50:50, v/v) mobile phase and a UV detection wavelength of 281 nm. The peak area versus 17 beta-estradiol concentration was found to be linear over the range of 0.0137-1347 mu g ml(-1) The HPLC method has also been used to determine the silicone solubilities and diffusion coefficients of the two related steroids. The almost 100-fold increase in 17 beta-estradiol-3-acetate release from the silicone core-type intravaginal rings compared to 17 beta-estradiol is shown to be due to a 60-fold increase in silicone solubility and a one and a half-fold increase in diffusitivity. The results demonstrate that an effective estrogen replacement therapy dose of 17 beta-estradiol may be administered from a silicone intravaginal reservoir device containing the labile 17 beta-estradiol-3-acetate prodrug. (C) 2000 Elsevier Science B.V. All rights reserved.

Elimination kinetic of 17 beta-estradiol 3-benzoate and 17 beta-nandrolone laureate ester metabolites in calves' urine

Efficient control of the illegal use of anabolic steroids must both take into account metabolic patterns and associated kinetics of elimination; in this context, an extensive animal experiment involving 24 calves and consisting of three administrations of 17 beta-estradiol 3-benzoate and 17 beta-nandrolone laureate esters was carried out over 50 days. Urine samples were regularly collected during the experiment from all treated and non-treated calves. For sample preparation, a single step high throughput protocol based on 96-well C-18 SPE was developed and validated according to the European Decision 2002/657/EC requirements. Decision limits (CC alpha) for steroids were below 0.1 mu g L-1, except for 19-norandrosterone (CC alpha = 0.7 mu g L-1) and estrone (CC alpha = 0.3 mu g L-1). Kinetics of elimination of the administered 17 beta-estradiol 3-benzoate and 17 beta-nandrolone laureate were established by monitoring 17 beta-estradiol, 17 alpha-estradiol, estrone and 17 beta-nandrolone, 17 alpha-nandrolone, 19-noretiocholanolone, 19-norandrostenedione, respectively. All animals demonstrated homogeneous patterns of elimination both from a qualitative (metabolite profile) and quantitative point of view (elimination kinetics in urine). Most abundant metabolites were 17 alpha-estradiol and 17 alpha-nandrolone (> 20 and 2 mg L-1, respectively after 17 beta-estradiol 3-benzoate and 17 beta-nandrolone laureate administration) whereas 17 beta-estradiol, estrone, 17 beta-nandrolone, 19-noretiocholanolone and 19-norandrostenedione were found as secondary metabolites at concentration values up to the mu g L-1 level. No significant difference was observed between male and female animals. The effect of several consecutive injections on elimination profiles was studied and revealed a tendency toward a decrease in the biotransformation of administered steroid 17 beta form. (c) 2008 Elsevier Ltd. All rights reserved.

Immunological homologues of the Arabidopsis thaliana beta 1 tubulin are polyglutamylated in Nicotiana tabacum

Peptide-specific antibody AABI, raised to the C-terminal 13 amino acids of Arabidopsis thaliana beta 1 tubulin, identifies a single electrophoretically separable beta-tubulin on 2-D-gel Western blots of total protein extracts from A. thaliana seedlings. We show that AABI crossreacts with two of the eight polyglutamylated beta-tubulin isoforms present in purified Nicotiana tabacum tubulin fractionated by high-resolution isoelectric focussing. Immunolocalisation studies using AAB1 revealed that the two N. tabacum polyglutamylated beta 1-tubulin isoforms are utilised in all four plant microtubule arrays (the interphase cortical array, the preprophase band, the spindle and the phragmoplast) indicating that there is no apparent subcellular sorting of these isotypes.

The role of transforming growth factor-beta 1 in steroidogenesis, cell proliferation, and apoptosis in cultured bovine granulosa cells

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