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ABSTRACT: A focused review of the risk of harms of anti-TNF inhibitors in adult rheumatic diseases was performed. An increased risk of serious infections, tuberculosis and other opportunistic infections has been reported across various studies, with etanercept appearing to have a modestly better safety profile in terms of tuberculosis and opportunistic infections, and infliximab posing a higher risk of serious infections. Evidence suggests no increase in risk of cancer with anti-TNF biologics, but there is an increased risk of non-melanoma skin cancer. Elderly patients appear to be at increased risk of incident or worsening heart failure with anti-TNF biologic use.
Immunotherapy 03/2013; 5(3):265-99. · 1.85 Impact Factor
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Jasvinder A Singh,
Daniel E Furst,
Aseem Bharat,
Jeffrey R Curtis,
Arthur F Kavanaugh,
Joel M Kremer,
Larry W Moreland,
James O'Dell,
Kevin L Winthrop,
Timothy Beukelman, [......],
John T Schousboe,
Eileen Moynihan,
Karen S Kolba, Archana Jain,
Elizabeth R Volkmann,
Harsh Agrawal,
Sangmee Bae,
Amy S Mudano,
Nivedita M Patkar,
Kenneth G Saag
Arthritis care & research. 05/2012; 64(5):625-39.
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Phosphorus Sulfur and Silicon and the Related Elements 06/2011; Sulfur(and Silicon and the Related Elements):1375-1378. · 0.72 Impact Factor
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ABSTRACT: The reactions of diorganotin precursors [R(2)Sn(OR(1))(OSO(2)R(1))](n) [R = R(1) = Me (1); R = Me, R(1) = Et (2)] with an equimolar amount of t-butylphosphonic acid (RT, 8-10 h) in methanol result in the formation of identical products, of composition [(Me(2)Sn)(3)(O(3)PBu(t))(2)(O(2)P(OH)Bu(t))(2)](n) (3). On the other hand, a similar reaction of 2, when carried out in dichloromethane, affords [(Me(2)Sn)(3)(O(3)PBu(t))(2)(OSO(2)Et)(2)·MeOH](n) (4). A plausible mechanism implicating the role of solvent in the formation of these compounds has been put forward. In addition, the synthesis of [(Me(2)Sn)(3)(O(3)PCH(2)CH(2)COOMe)(2)(OSO(2)Me)(2)](n) (5) and [R(2)Sn(O(2)P(OH)CH(2)CH(2)COOMe)(OSO(2)R(1))](n) [R = Et, R(1) = Me (6); R = (n)Bu, R(1) = Et (7)] has been achieved by reacting 1 and related diorganotin(alkoxy)alkanesulfonates with 3-phosphonopropionic acid in methanol. The formation of a methylpropionate functionality on the phosphorus center in these structural frameworks results from in situ esterification of the carboxylic group. X-ray crystallographic studies of 1-7 are presented. The structures of 1 and 2 represent one-dimensional (1D) coordination polymers composed of alternate [Sn-O](2) and [Sn-O-S-O](2) cyclic rings formed by μ(2)-alkoxo and sulfonate ligands, respectively. For 3-5 and 7, variable bonding modes of phosphonate and/or sulfonate ligands afford the construction of two- and three-dimensional self-assemblies that are comprised of trinuclear tin entities with an Sn(3)P(2)O(6) core as well as [Sn-O-P-O](2) and/or [Sn-O-S-O](2) rings. The formation of a 1D coordination polymer in 6 is unique in terms of repeating eight-membered cyclic rings containing Sn, O, P, and S heteroatoms. The contribution from hydrogen-bonding interactions is also found to be significant in these structures.
Inorganic Chemistry 02/2011; 50(4):1339-50. · 4.60 Impact Factor
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ABSTRACT: Hydrolysis of the mixed-ligand dimethyltin(ethoxy)ethanesulfonate, [Me(2)Sn(OEt)(OSO(2)Et)](n) (1a) in moist hexane proceeds via disproportionation and partial cleavage of Sn-C and S-C bonds to afford a novel oxo-/hydroxo- organotin cluster of the composition [(Me(2)Sn)(MeSn)(4)(OSO(2)Et)(2)(OH)(4)(O)(2)(SO(3))(2)] (1) bearing both mono- and dimethyltin fragments and in situ generated sulfite (SO(3)(2-)) anion in the structural framework. On the other hand, similar reactions with analogous mixed ligand diorganotin precursors, [R(2)Sn(OR(1))(OSO(2)R(1))](n) (R = n-Bu, R(1) = Et (2a); R = Et, R(1) = Me (3a)), result in the formation of tetranuclear diorganotin clusters, [{(n-Bu(2)Sn)(2)(OH)(OSO(2)Et)}O](2) (2) and [(Et(2)Sn)(4)(OH)(O)(2)(OSO(2)Me)(3)] (3), respectively. The activation of the Sn-C or S-C bond is not observed in these cases. These findings provide a preliminary insight into the unusual reactivity of 1a under hydrolytic conditions.
Inorganic Chemistry 05/2010; 49(10):4708-15. · 4.60 Impact Factor
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ABSTRACT: The coordination-driven self-assemblies of mixed-ligand dialkyltin derivatives, [(Et(2)Sn)(4) (O(2)P(OH)Me)(2)(O(3)PMe)(2)(OSO(2)Et)(2) x 2 H(2)O](n) 1, [(Et(2)Sn)(3)(O(3)PMe)(2)(OSO(2)Me)(2) x CHCl(3)](n) 2, and [(Me(2)Sn)(3)(O(3)PBu(t))(2)(OSO(2)Me)(2) x 2 CHCl(3)](n) 3 have been achieved by reacting the tin precursors, [R(2)Sn(OR(1))(OSO(2)R(1))](n) (R = Et, R(1) = Et (1a), Me (2a); R = Me, R(1) = Me (3a)) with an equimolar amount of methylphosphonic/t-butylphosphonic acid under mild conditions (rt, 8 h, CH(2)Cl(2)). These have been characterized by IR and multinuclear ((1)H, (13)C, (31)P, and (119)Sn) NMR spectroscopy as well as single crystal X-ray diffraction. The asymmetric unit of 1 is composed of a tetranuclear, Sn(4)(mu(2)-PO(2))(2)(mu(3)-PO(3))(2) core bearing an appended ethanesulfonate group on each terminal tin (Sn2) atom and two P(OH)...O hydrogen bonded water molecules. The ladder-like structural motif thus formed is extended into one-dimensional polymeric chains by virtue of bridging bidentate mode of the sulfonate groups. These chains are linked by O-H...O(S) hydrogen bonds involving H(2)O molecules and oxygen atoms of the sulfonate groups. The asymmetric units of 2 and 3 are composed of trinuclear tin clusters with a Sn(3)(mu(3)-PO(3))(2) core and two dangling methanesulfonate groups which are covalently bonded to the tin centers. The construction of three-dimensional self-assemblies is effected by variable bonding modes (mu(2), mu(3) in 2; mu(2) in 3) of the methanesulfonate groups. Both the structural motifs possess five- and six-coordinated tin atoms and form rectangular channels which are occupied by CHCl(3) molecules.
Inorganic Chemistry 04/2009; 48(8):3608-16. · 4.60 Impact Factor
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ABSTRACT: Mixed-ligand diorganotin esters, [R 2Sn(OP(O)(OH)Ph)(OS(O) 2R (1))] n [R = n-Bu, R (1) = Me ( 1), n-Pr ( 2); R = Et, R (1) = Me ( 3)], have been synthesized by reacting the tin precursors, R 2Sn(OR (1))OS(O) 2R with an equimolar amount of phenylphosphonic acid under mild conditions (room temperature, 6-8 h, CH 2Cl 2). These have been characterized by IR, multinuclear ( (1)H, (13)C{ (1)H}, (31)P, and (119)Sn) NMR, and single crystal X-ray diffraction studies. The asymmetric unit of 1 is comprised of a tetramer with four crystallographically unique tin atoms. The structure reveals a central eight-membered (Sn-O-S-O) 2 cyclic ring with two exocyclic tin atoms, which results from micro 3-binding of the two methanesulfonate groups. The remaining two sulfonates are monodentate and contribute in O...HO(P) hydrogen bonding. The molecular structure is extended into a 3D coordination polymer with the aid of hydrogenphenylphosphonate group on each tin atom, acting in a micro 2-O 2P mode and forms a series of eight-membered (Sn-O-P-O) 2 rings in the structural framework. 2 and 3 are isostructural and represent linear 1D coordination polymers via micro 2-binding mode of both alkanesulfonate and hydrogenphenylphosphonate groups.
Inorganic Chemistry 08/2008; 47(13):5930-5. · 4.60 Impact Factor
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04/2002;
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04/2002;
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ABSTRACT: Diethyltin(methoxy)methanesulfonate reacts readily with equimolar amount of t-butylphosphonic acid (RT, 8–10 h) in moist dichloromethane and methanol to afford [(Et2Sn)6(O3PBut)4(OSO2Me)4·CH2Cl2]n (1) and [(Et2Sn)6(O3PBut)4(OSO2Me)4·2H2O]n (2), respectively. The identity of these compounds has been established by IR, multinuclear (1H, 13C, 31P and 119Sn) NMR as well as X-ray crystallographic studies. Despite apparent similarity in the composition, a marked difference in the structural motifs between 1 and 2 is evident in the solid state. For 1, the formation of three-dimensional self- assembly results from μ3-phosphonate and μ2, μ3-sulfonate binding modes and exhibits continuous channel of voids which are occupied by disordered CH2Cl2 molecules. In contrast, the sulfonate ligands in 2 act exclusively in μ2-fashion and hydrogen bonding interactions (O–H⋯O) between coordinated water molecules and methanesulfonate groups is significant in the construction of 3D supramolecular assembly.Graphical abstractSynthesis and structural characterization of mixed-ligand diethyltin-based three-dimensional assemblies derived from sulfonate/phosphonate ligands are described.Highlights► Diethyltin(methoxy)methanesulfonate reacts with t-butylphosphonic acid under mild conditions in presence of trace amount of water. ► The formation of simple molecular constructs via disproportionation of tin precursor is key step in these reactions. ► Association of the molecular constructs form coordination driven 3D self-assemblies.
Inorganica Chimica Acta. 372(1):108-114.
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ABSTRACT: A flow-injection method is described for the determination of acetaminophen (paracetamol) (linear range 0.8.100 gmg ml−1 based on its oxidation with 2-iodylbenzoate in acid medium to produce a yellow-orange compound, believed to be N-acetyl-1,4-benzoquinoneimine, which is monitored at 445 nm. The sample throughput is 360 h−1. The precision (R.S.D) of determination was 0.5−2%. The method was applied to the determination of acetaminophen in drug formlations, and evaluated by analyzing spiked sample solutions, a mean recovery of 1006% (range 96.3−105.2%) being obtained. No interference was observed from the common exicipients of drugs and other active substances, e.g., dipyrone, acetylsalicylic acid, salicylamide and oxyphenbutzone. Te possible application of the proposed method in content uniformity test and drug dissolution studies is indicated. Comparison of the present method with a liquid chromatographic method for acetaminophen determination gave a mean difference of 1.2% (range 0.4−2.4%).
Analytica Chimica Acta.
