bluuebunny/crossref_metadata_2025 huggingface dataset:
[Ph4P][(C5H6N3O3)M(CO)5] (M = Cr, Mo, W; C5H7N3O3 = 1,3‐Dimethyl‐cyanuric Acid). Organometallic Complexes of the 1,3‐Dimethylcyanurate Ligand
Authors: Abu‐Salem Qutaiba , Maichle‐Mößmer Cäcilia , Niquet Elke , Kuhn Norbert
Published: October 2008

1,3‐Dimethylcyanuric acid (DMCH) forms on deprotonation and reaction with TlF its thallous salt Tl[DCM] (2) which is converted to the phosphonium salt [PPh4][DCM] (3). On the reaction with M(CO)6, the pentacarbonylmetalate salts [Ph4P][(DMC)M(CO)5], M = Cr (4a), Mo (4b) and W (4c) are obtained. IR and NMR data of 4 reveal the DMC anion (1) to have coordination properties similar to those of pyridine. The crystal structures of 4a and 4c are reported.
A New Compound in the Cu‐In System – the Synthesis and Structure of Cu10In7
Authors: Piao Shuying , Lidin Sven
Published: October 2008

A new binary phase, Cu10In7, was found during the investigation of the η‐phase field in the Cu‐In system. Single crystals of Cu10In7 were grown from a melt under an inert atmosphere. The compound crystallizes in the monoclinic space group C2/m with cell parameters a = 13.8453(2) Å, b = 11.8462(1) Å, c = 6.7388(1) Å and β = 91.063(1). The structure is based on a unit of face‐sharing octahedra consisting of five Cu4In2 octahedra terminated by Cu5In octahedra at both ends. The crystal structure is closely related to the Cu11In9 structure type.
Hydrothermal Synthesis, Crystal Structure and Electrochemical Property of a Ribbon‐like Coordination Polymer based on Octamolybdate Anions
Authors: Zhao Yi , You Wansheng , Dai Limei , Zhang Lancui , Song Dawei , Dalian Qinghua Du
Published: October 2008

A new coordination polymer based on octamolybdate anions and copper(II)‐mebpa complex fragments, namely, [{Cu(mebpa)}2β‐Mo8O26] (1), where mebpa is bis(2‐pyridylmethyl)methylamine, has been synthesized under the hydrothermal reaction and characterized by single‐crystal X‐ray diffraction, IR, thermogravimetric analysis and cyclic voltammetry. 1 is formed from β‐[Mo8O26]4− anions with {Cu(mebpa)}2+ fragments covalently attached via terminal oxygen atoms into a ribbon‐like chain. The β‐[Mo8O26]4− anions act as sexadentate ligands and the CuII ions adopt the common Jahn‐Teller distorted “4+2” coordination. Owing to the weak C‐H···O hydrogen bonding interactions, two crystallographically independent {CuN3O3} octahedra are located in the A and B layers respectively. The chemically modified carbon paste electrode (MCPE) displays well‐defined cyclic voltammograms with three two‐electron reversible redox couples in acidic aqueous solution and electrocatalytic activities toward the reduction of nitrite.
Assembly of Supramolecular Networks with the Inclusion of Water Chains, Cyclic Hepta and Octa Water Clusters
Authors: Sun Chang‐Yan , Zheng Xiang‐Jun , Li Wen‐Jun , Wang Ming‐Wen , Fang Chun‐Ying
Published: October 2008

Three new supramolecular compounds were synthesized and characterized with the formula of [Zn4(picO)4(phen)4]·11.25H2O (1), [Zn4(picO)4(2,2′‐bpy)4(H2O)4]·12H2O (2), and [Zn3(picO)3(bpe)5(H2O)3]n·8.5nH2O (3) (H2picO = 6‐hydroxypicolinic acid; phen = 1,10‐phenanthroline; 2,2′‐bpy = 2,2′‐bipyridine; bpe = 1,2‐bis(4‐pyridyl)ethane). For complexes 1 and 2, picO ligands adopt tridentate, tetradentate and bidentate coordination modes to link zinc(II) ions into dimers, which are extended into 3D supramolecular structures through hydrogen bonds. Water chains with cyclic page‐like octamer and boat‐like heptamer water clusters are included, respectively. Complex 3 is of a 2D brick‐wall structure. Triple interpenetration occurs, and there are still cyclic chair‐like octamer water clusters in the channels. The fluorescent properties of complexes 1‐3 have also been investigated.
Syntheses, Crystal Structures and Luminescent Properties of Three Inorganic‐Organic Hybrid Frameworks Constructed from 4,5‐Imidazoledicarboxylate
Authors: Wang Dong‐E , Wang Feng , Meng Xiang‐Gao , Ding Yu , Wen Li‐Li , Li Dong‐Feng , Lan She‐Ming
Published: October 2008

Three inorganic‐organic hybrid frameworks [Mn(HIMDC)(4,4′‐bipyo)0.5(H2O)]n (1), [Cd(H2IMDC)2(2,2′‐bipyo)] (2) and [Ca(HIMDC)(H2O)2·H2O]n (3) (H3IMDC = 4,5‐imidazoledicarboxylate; 4,4′‐bipyo = 4,4′‐bipyridine‐N,N′‐dioxide; 2,2′‐bipyo= 2,2′‐bipyridine‐N,N′‐dioxide) have been hydrothermally synthesized and characterized by the elemental analyses, IR spectra, TG analysis and the single crystal diffraction. Both compounds 1 and 3 exhibit 2D layers while 2 is a monomer. It is noteworthy that compound 2 exhibits strong fluorescent emission in the solid state at room temperature.
Synthesis, Characterization and Electrochemistry of New Soluble Porphyrazine Complexes Bearing Octakis 3‐Methylbutylthio Substituents
Authors: Erdoğmuş Ali , Koca Atıf , Avcıata Ulvi , Gül Ahmet
Published: October 2008

Porphyrazines, MPz (M = Mg, H, Ni, Zn and Co) with octakis 3‐methylbutylthio substituents have been synthesized starting with the corresponding unsaturated dicarbonitrile derivative. These new compounds have been characterized by UV‐Vis, FT‐IR, 1H NMR, MS and elemental analysis methods. Voltammetric properties of the complexes were also investigated by CV, DPV and CPC techniques. Electrochemical studies show that three reversible one electron reductions and one reversible one electron oxidation processes (two for CoIIPz) are observed for all of the complexes. The E1/2 values are similar for the H2Pz, NiIIPz and ZnIIPz derivatives with negative shift due to the different effective nuclear charges of the central metal ion. Peak to peak separations and separation between the first reduction and first oxidation couples related with the HOMO‐LUMO gap of the complexes are in harmony with the common porphyrazine complexes.
Neue Kronenether‐stabilisierte Oxoniumhalogenochalkogenate: [H3O(Dibromo‐benzo‐18‐Krone‐6)]2[Se3Br10] und [H5O2(Bis‐dibromo‐dibenzo‐24‐Krone‐8]2[Se3Br8]
Authors: Beckmann Illenora , Läge Mechtild , Krebs Bernt
Published: October 2008

Novel Oxonium Halogenochalcogenates Stabilized by Crown Ethers: [H3O(Dibromo‐benzo‐18‐crown‐6)]2[Se3Br10] and [H5O2(Bis‐dibromo‐dibenzo‐24‐crown‐8]2[Se3Br8]

Two novel complex oxonium bromoselenates(II,IV) and –(II) are reported containing [H3O]+ and [H5O2]+ cations coordinated by crown ether ligands. [H3O(dibromo‐benzo‐18‐crown‐6)]2[Se3Br10] (1) and [H5O2(bis‐dibromo‐dibenzo‐24‐crown‐8]2[Se3Br8] (2) were prepared as dark red crystals from dichloromethane or acetonitrile solutions of selenium tetrabromide, the corresponding unsubstituted crown ethers, and aqueous hydrogen bromide. The products were characterized by their crystal structures and by vibrational spectra. 1 is triclinic, space group $\rm P{\bar 1}$ (Nr. 2) with a = 8.609(2) Å, b = 13.391(3) Å, c = 13.928(3) Å, α = 64.60(2)°, β = 76.18(2)°, γ = 87.78(2)°, V = 1404.7(5) Å3, Z = 1. 2 is also triclinic, space group $\rm P{\bar 1}$ with a = 10.499(2) Å, b = 13.033(3) Å, c = 14.756(3) Å, α = 113.77(3)°, β = 98.17(3)°, γ = 93.55(3)°. V = 1813.2(7) Å3, Z = 1. In the reaction mixture complex redox reactions take place, resulting in (partial) reduction of selenium and bromination of the crown ether molecules. In 1 the centrosymmetric trinuclear [Se3Br10]2− consists of a central SeIVBr6 octahedron sharing trans edges with two square planar SeIIBr4 groups. The novel [Se3Br8]2− in 2 is composed of three planar trans‐edge sharing SeIIBr4 squares in a linear arrangement. The internal structure of the oxonium‐crown ether complexes is largely determined by the steric restrictions imposed by the aromatic rings in the crown ether molecules, as compared to complexes with more flexible unsubstituted crown ether ligands.
Platinum and Palladium Complexes Bearing New (1R,2R)‐(–)‐1,2‐Diaminocyclohexane (DACH)‐Based Nitrogen Ligands: Evaluation of the Complexes Against L1210 Leukemia
Authors: Abu–Surrah Adnan S. , Kettunen Mika , Leskelä Markku , Al‐Abed Yousef
Published: October 2008

The reaction of (1R,2R)‐(–)‐1,2‐diaminocyclohexane (1) [DACH] with the aldehyde (1R)‐(–)‐myrtenal (2) in MeOH afforded the bidentate diimine ligand, (1R,2R)‐(–)‐N1,N2‐bis{(1R)‐(–)myrtenylidene}‐1,2‐diaminocyclohexane (3) in a high yield. Reduction of 3 using LiAlH4 led to the formation of the desired ligand (4) (1R,2R)‐(–)‐N1,N2‐bis{(1R)‐(–)myrtenyl}‐1,2‐diaminocyclohexane. Treatment of compound 4 with K2PtCl4 or K2PdCl4 yielded the corresponding platinum(II) and palladium(II) complexes, Pt‐5 and Pd‐6, respectively. The reaction of compound 3 with K2PtCl4 gave the diimine complex Pt‐7. The cytotoxic activity of the complexes Pt‐5, Pd‐6 and Pt‐7 was tested and compared to the approved drugs, cisplatin (Cis‐Pt) and oxaliplatin (Ox‐Pt). The complexes (Pt‐5, Pd‐6 and Pt‐7) inhibit L1210 cell line proliferation with an IC50 of 0.6, 4.2, and 0.7 μL, respectively as evidenced by measuring thymidine incorporation.
Aryldimethylsilyl Modified Hypersilanes
Authors: Hauber Sven‐Oliver , Niemeyer Mark
Published: October 2008

Aryldimethylsilyl‐substituted hypersilanes ArSiMe2Hyp [Hyp =Si(SiMe3)3; Ar = Mes (3a), Bph (3b), Mph (3c), Pph (3d), Tph (3e); Dpp (3f); with Mes = 2,4,6‐Me3C6H2, Bph = 2‐PhC6H4, Mph = 2‐MesC6H4, Pph = 2′,3′,4′,5′,6′‐pentamethylbiphenyl2‐yl, Tph = 2′,4′,6′‐triisopropylbiphenyl‐2‐yl and Dpp = 2,6‐Ph2C6H3] have been synthesized by a multi‐step reaction starting from the readily available starting materials ArI and (thf)xKHyp. For this purpose the aryl iodides were first converted into the lithium aryls by lithium‐halogen exchange with n‐butyl lithium. A salt‐metathesis reaction with SiMe2Cl2 gave the corresponding arylchlorodimethylsilanes (2a–e) in excellent yields. Finally, reaction of 2a–e with (thf)xKHyp afforded the hypersilanes 3a–e in yields up to 86 %. Bis(aryldimethylsilyl)‐substituted silanes (ArSiMe2)2Si(SiMe3)2 (Ar = Mph (4c), Tph (4e)) were obtained by the reaction of 3c or 3e with KOtBu and the corresponding chlorosilanes 2c or 2e. All new compounds have been characterized by melting point, elemental analysis, 1H, 13C, and 29Si NMR spectroscopy and for selected species by IR spectroscopy or mass spectrometry. In addition, the solid‐state structures of silanes 3a–d, 3f, and 4c have been investigated by single crystal X‐ray diffraction.
Temperature‐dependent Changes of the Crystal Structure of Li2B4O7
Authors: Sennova Natalia , Bubnova R. S. , Cordier G. , Albert B. , Filatov S. K. , Isaenko L.
Published: October 2008

The crystal structure of Li2B4O7 was studied by single crystal X‐ray diffraction whilst the substance was cooled down from room temperature to −150 °C. The title compound crystallizes in the tetragonal, non‐centrosymmetric space group I 41cd (no. 110), a = 9.475(5) Å (r.t.), c = 10.283(6) Å (r.t.), R values for seven different data sets vary from 2.6 to 2.9 %. Low‐temperature single crystal examinations were combined with low‐temperature powder X‐ray diffraction experiments (−189 – +27 °C). The results are discussed in comparison with data earlier obtained at high temperatures (20 – 500 °C). No phase transitions or abrupt changes of the crystal structure were observed. The coordination sphere of the lithium ions is that of a distorted tetrahedron and remains almost unchanged, although the coordination number of the lithium ions decreases slightly with rising temperature, similarly to what was found for LiB3O5. An expected rigidity of the boron‐oxygen groups was confirmed. The thermal deformations of the [B4O7]2− framework occur according to the hinge mechanism. This indicates that the LiO4 chains change their winding on cooling, which leads to deformations along c.
Homo‐ and Heteropentanuclear Coordination Compounds with Td Symmetry – the Solid State Structures of [MZn4(L)4(L′)6] (M = CoII or Zn; L = chloride or acac; L′ = 1,2,3‐benzotriazolate)
Authors: Biswas Shyam , Tonigold Markus , Volkmer Dirk
Published: October 2008

The syntheses of homo‐ and heteropentanuclear coordination compounds with the molecular formulae [MZn4(L)4(L′)6] (M = CoII or Zn; L = chloride or acac; L′ = 1,2,3‐benzotriazolate) are reported. These compounds display a highly symmetric coordination unit consisting of a central metal ion (M = CoII or Zn) which is octahedrally coordinated by 6 tridentate benzotriazolate‐type ligands via their N(2) donor atom. The benzotriazolate ligands span the edges of an imaginary tetrahedron thus providing four coordination sites at the corners of the tetrahedron, which are then filled by four zinc ions. The coordination shell of the latter are completed by bidentate acetylacetonate (acac) ligands or by chloride anions, respectively.

The solid state structures of two homopentanuclear metal complexes, namely [Zn5(acac)4(bta)6]·4C6H12 (1) (acacH = acetylacetone; btaH = 1,2,3‐benzotriazole), and [Zn5Cl4(Me2bta)6]·2DMF (2) (Me2btaH = 5,6‐dimethyl‐1,2,3‐benzotriazole) were determined by single crystal X‐ray structure analysis. The heteropentanuclear metal complex [CoIIZn4Cl4(Me2bta)6]·2DMF (3) is isostructural with compound 2. Compound 1 was synthesized from stoichiometric amounts of Zn(acac)2 and btaH employing dichloromethane as solvent. The synthesis of compound 2 requires addition of an auxiliary base to the DMF solution of anhydrous ZnCl2 and Me2btaH. For compound 3 a stoichiometric ratio of Co(NO3)2·6H2O, anhydrous ZnCl2 and Me2btaH was employed during synthesis. Phase purity of all compounds was proved by X‐ray powder diffraction (XRPD) analysis, IR spectroscopy, and elemental analysis. Crystal data: for 1 (C80H100N18O8Zn5): monoclinic, space group P21/c with a = 23.781(5) Å, b = 16.000(3) Å, c = 25.170(5) Å, β = 115.29(3)°, V = 8659(3) Å3, Z = 4, ρ = 1.357 g cm−3. For 2 (C54H62Cl4N20O2Zn5): cubic, space group $Fd{\bar 3}m$ with a = 23.367(3) Å, V = 12759(3) Å3, Z = 8, ρ = 1.553 g cm−3. For 3 (C54H62Cl4CoN20O2Zn4): cubic, space group $Fd{\bar 3}m$ with a = 23.443(3) Å, V = 12884(3) Å3, Z = 8, ρ = 1.532 g cm−3.
Electrocrystallization of Tetra‐ and Hexa‐coordinated Silver(II) Compounds Based on 4,4′‐Dimethyl‐2,2′‐Bipyridine Ligand – Single Crystal Structures and Magnetic Studies
Authors: Kandaiah Sakthivel , Peters Eva‐Maria , Jansen Martin
Published: October 2008

In this paper we report on the potential dependent electrocrystallization of [Ag(4,4′‐dimethyl‐2,2′‐bipyridine)2(NO3)2] (1) and Ag(4,4′‐dimethyl‐2,2′‐bipyridine)(NO3)2 (2) from the same electrolytic bath. Thus it has been shown for the first time that the coordination number of silver ion to ligands can be tuned by the electrocrystallization potential. The single crystal structure analysis [1: C2/c, a = 18.6308(15), b = 14.5708(12), c = 11.5867(10) Å, β = 126.5910(10)°, Z = 4, R = 3.9 %] [2: P21/c, a = 8.5865(11) b = 11.0157(14) c = 16.4554(10) Å, β = 111.102(10), Z = 4 , R = 3.5 %] show divalent silver to be in an approximately square planar surrounding. Both complexes are paramagnetic following Curie's law with magnetic moments of 1.86 μB and 1.72 μB respectively.
Probing the Reactivity of the Potent AgF2 Oxidizer. Part 2: Inorganic Compounds
Authors: Malinowski Przemysław , Mazej Zoran , Grochala Wojciech
Published: October 2008

The reactivity of AgIIF2 towards forty two inorganic compounds containing oxo‐ and chloro‐ ligands, has been investigated. Five families of compounds were studied: (i) binary oxides of metals and nonmetals, (ii) ternary salts of inorganic oxo acids, (iii) concentrated or anhydrous oxo‐ acids, (iv) binary and ternary chlorides and (v) oxochlorides. At low temperatures up to 200 °C AgF2 readily oxidizes HgO, B2O3, PbO2, As2O5, Ag2SO4, LiBO2, K2CO3, KVO3, Ag2WO4, and AgMnO4 with concomitant oxygen evolution. In the same conditions V2O5, CrO3, MoO3, WO3, CuO, Tl2O3, I2O5, Re2O7, K2SO4, HgSO4, KSO3F, KNO3, KClO4, KIO4, BaCrO4, KMnO4 and KReO4 resist the action of AgF2 but many of these compounds get oxidized at higher temperatures (up to nearly 300 °C). Substantial inertness of sulfates, chromates, nitrates, perchlorates, permanganates and perrhenates suggests that one might attempt to synthesize salts of divalent silver with these anions. AgF2 vigorously reacts with H2SO4 (fuming, 30% SO3), HSO3Cl (100%), HClO4 (70%), and HNO3 (fuming, 100%) at room temperature yielding salts of AgI and O2; for HClO4 and HNO3 pre‐cooled to −35 °C metastable perchlorate / nitrate complexes of AgII are obtained. Anhydrous HSO3F behaves similar to HSO3CF3 (see Part 1 of this series) yielding slow methathetical conversion of AgF2 without concomitant redox reaction.

Majority of chlorides and oxochlorides studied (AgCl, AuCl3, KAuCl4, WCl6, WOCl4, MoOCl4, MoO2Cl2) react with AgF2 at temperatures below 160 °C. Reaction with SiCl4 (in contrast to CCl4) is violent and very exothermic at room temperature. Liquid CrO2Cl2 (at room temperature) and solid WO2Cl2 (up to 180 °C) are kinetically inert to AgF2. We do not observe intercalation of AgF2 with various redox—inert oxo‐ and chloro‐ Lewis bases at the experimental conditions.
Siloxanediolates of the Rare Earth Elements – An Eight‐Membered Inorganic Ring System containing Ytterbium
Authors: Gießmann Stephan , Blaurock Steffen , Edelmann Anja , Lorenz Volker , Edelmann Frank T.
Published: October 2008

Treatment of anhydrous YbCl3 with LiN(SiMe3)2 followed by reaction with 1 equivalent of 1,1,3,3,5,5‐hexaphenyl‐1,3,5‐trisiloxanediol afforded the first mono(trisiloxanediolate) complex of a rare earth element. The compound [Ph2Si(OSiPh2O)2]Yb(THF)(μ‐Cl)3Li2(THF)3 (1) was isolated in the form of colorless crystals in very high yield (93%). A single‐crystal X‐ray diffraction study confirmed the presence of an eight‐membered inorganic ring system containing ytterbium. Coordination of one THF ligand and retention of two equivalents of lithium chloride lead to formation of an “ate” complex.
Synthese und Koordinationsverhalten von (Ph3SnO)3As. Die Kristallstrukturen von (Ph3SnO)3As und [{(Ph3SnO)3As}Fe(CO)4]
Authors: Herntrich Tobias , Merzweiler Kurt
Published: October 2008

Synthesis and Coordination Behaviour of (Ph3SnO)3As. The Crystal Structures of (Ph3SnO)3As and [{(Ph3SnO)3As}Fe(CO)4]

(Ph3SnO)3As (1) was obtained from the reaction of Ph3SnOH with As2O3 in a dichloromethane/water mixture as solvent. Upon recrystallization from DMF 1 forms orthorhombic crystals, space group P212121, with a = 977.3(2), b = 1903.5(3) and c = 2600.9(5) pm (at 220 K). In 1 the As atom is bound to three OSnPh3 groups with As–O distances of 171.9(3)–174.9(3) pm. Reaction of 1 with Fe2(CO)9 gives [{(Ph3SnO)3As}Fe(CO)4] (2). 2 crystallizes monoclinic, space group P21/n with a = 2242.3(5), b = 1112.6(2), c = 2353.0(5) pm and β = 111,46(2)° (at 220 K). In 2 the iron atom exhibits a trigonal bipyramidal coordination with the (Ph3SnO)3As ligand in an axial position. The Fe–As bond length is 230.5(1) pm.
Structural and Spectroscopic Studies of [M((x)tu)4]+ Systems (M = Cu, Ag; (x)tu = (substituted) Thiourea)
Authors: Bowmaker Graham A. , Pakawatchai Chaveng , Skelton Brian W. , Thanyasirikul Yupa , White Allan H.
Published: October 2008

In a low‐temperature redetermination of improved precision of the structure of [Cu(tu)4]2(SiF6) (‘tu’ = thiourea, SC(NH2)2), Cu–S range between 2.3173–2.3433(8), < > 2.336(11) Å, with S–Cu–S 92.72(3)–118.75(12)°. The first structure determination of a 1:4 adduct of a silver(I) salt with a (substituted) thiourea ligand is also reported, for silver(I) nitrate with ‘ethylenethiourea’, (‘etu’ = SC(NHCH2)2), as a monohydrate [Ag(etu)4](NO3)·H2O, wherein Ag–S range between 2.544–2.637(2), < > 2.59(4) Å, S–Ag–S 87.88–117.57(7)°. Bands in the far‐IR spectra of these compounds are assigned to ν(MS) modes, and the frequencies are compared with those predicted by previously established correlations between ν(MS) and the M–S bond length d(MS) for copper or silver complexes with tu or etu ligands.
Three‐dimensional Hemidirected Mixed‐ligand Lead(II) Coordination Polymer, [Pb2(bpa)2(SCN)3(NO3)]n (bpa = 1,2‐di(4‐pyridyl)ethane)
Authors: Abedini Jafar , Morsali Ali , Zeller Matthias
Published: October 2008

A new 3D hemidirected mixed‐ligand lead(II) coordination polymer with the ligand 1,2‐di(4‐pyridyl)ethane bpa) and the two metal coordinated anions nitrate and thiocyanate, [Pb2(bpa)2(SCN)3(NO3)]n (1), has been synthesized and characterized by CHN elemental analysis, IR‐, 1H‐ and 13C NMR spectroscopy. The single crystal X‐ray data of compound 1 show that the complex is a three‐dimensional coordination polymer with two different Pb atoms with stereoactive electron lone pairs and six‐ and five‐coordinate hemidirected geometries, respectively.
Unusual Solid Solutions in the System Ge‐Sb‐Te: The Crystal Structure of 33R‐Ge4−xSb2−yTe7 (x, y ≈ 0.1) is Isostructural to that of Ge3Sb2Te6
Authors: Schneider Matthias N. , Oeckler Oliver
Published: October 2008

Whereas for a series of layered compounds with the general formula (GeTe)n(Sb2Te3)m the stoichiometry allows to predict the structure type and the average thickness of the hexagonal atom layers, these rules are not generally applicable for GeTe‐rich compounds like Ge4Sb2Te7. A 39R layer stacking is expected, however, single crystal diffraction studies reveal a 33R layered structure ($R{\bar 3}m$, a = 4.1891(5) Å, c = 62.169(15), R = 0.047) closely related to that of Ge3Sb2Te6. This is also corroborated by the average layer thickness that can be determined from the strong reflections of powder patterns and exhibits a direct relation to the structure type. Mixed occupancy of cation positions with Ge and Sb and possibly defects allow this unusual range of homogeneity. Bulk material of the kinetically stable compound can be synthesized by quenching stoichiometric melts of the pure elements and subsequent annealing.
Atomistic Simulation Study of Cu0.327Ni0.673 Alloys: from Solid Solution to Phase Segregation
Authors: Zahn Dirk , Haarmann Frank , Grin Yuri
Published: October 2008

We present a combined Monte‐Carlo/molecular dynamics study of a Cu0.327Ni0.673 alloy system. On the basis of nearest‐neighbor coordination number analyses atomic clustering and phase segregation is explored. Along this line, free energy profiles are calculated and separated into entropic and energetic contributions. The competition of both terms was found in accordance to the experimental phase diagrams (phase separation of the solid solution below about 600 Kelvin). Two independent simulation runs were performed. At 1000 Kelvin the observed configurations correspond to solid solutions exhibiting a weak tendency to cluster atoms of identical species. At room temperature the energetic favoring of atomic separation is clearly dominant and leads to the formation of Ni‐rich and Cu‐rich domains. The latter are separated by interfacial regions whose width ranges from 0.5 to 1 nanometers.
Koordinationspolymere aus Metallotripyrrinen
Authors: Bröring Martin , Prikhodovski Serguei
Published: October 2008

Dieser Forschungsbericht behandelt jüngere Entwicklungen in der Koordinationschemie von Tripyrrinen und verwandten Liganden mit einem Schwerpunkt auf der Strukturchemie von Koordinationspolymeren. Der Tripyrrinligand ist einzigartig in seiner Fähigkeit, ein‐ und dreidimensionale supramolekulare Strukturen aus pentakoordinierten Übergangsmetallionen zu stabilisieren. Dies gelingt durch eine effektive sterische Blockierung der sechsten Koordinationsstelle am chelatisierten Ion. Lineare Koordinationspolymere wurden mit einer Vielzahl anionischer Brückenliganden wie Trifluoracetat, Azid, Thio‐ und Selenocyanat sowie mit Pseudohalogeniden höherer Ordnung erhalten. Der Einsatz von Cyanidometallaten erlaubt zudem die Darstellung homo‐ und heterodimetallischer Spezies, die in zwei Fällen strukturell charakterisiert wurden. Neben den kovalenten koordinativen Bindungen wurden verschiedene sekundäre Wechselwirkungen wie Wasserstoffbrückenbindungen oder π‐Stapelkontakte als stabilisierende Zusatzelemente gefunden, die eine Darstellung von Materialien mit funktionalisierten inneren Oberflächen ermöglichen.
Kinetische Untersuchungen zur Hydrierung von Kohlendioxid zu Ameisensäure mit einem Rhodiumkomplex als Katalysator
Authors: Dietrich Jens , Schindler Siegfried
Published: October 2008

Kinetic Studies on the Hydrogenation of Carbon Dioxide to Formic Acid using a Rhodium Complex as Catalyst

A detailed kinetic analysis has been performed on the hydrogenation of carbon dioxide with the complex [(dppp)2RhH] (dppp = 1,3‐bis(diphenyl‐phosphino)propane in DMSO using stopped‐flow techniques. Activation parameters including the activation volume for this reaction as well as for the related reaction of the formation of the dihydrogen complex [(dppp)2RhH2]HCO2 were obtained and thus allowed the formulation of a mechanism for this reaction cycle.
Structural and Spectroscopic Evidence for Marginal Metal‐to‐Ligand Charge Transfer in Complexes Pt(abpy)Me3X, abpy = 2,2′‐Azobispyridine, X = Cl, Br, I
Authors: Dogan Akbey , Kavakli Cüneyt , Sieger Monika , Niemeyer Mark , Sarkar Biprajit , Kaim Wolfgang
Published: October 2008

The title complexes (X = Cl, 1a; X = Br, 1b; X = I, 1c) could be characterized by 1H‐NMR spectroscopy and were partially studied by X‐ray diffraction (1b,c), cyclic voltammetry and UV‐Vis spectroscopy (1b). The short N=N bonds of about 1.26Å, the occurrence of only weak charge transfer absorptions in the visible, the rather small shift of the reduction potential, and the small g anisotropy in the EPR spectrum of 1b˙− indicate an only a marginal π interaction between the organometallic PtIV fragments and the excellent π acceptor abpy.
Die Kristallstrukturen von [Ph3PMe]Cl·CH2Cl2, [Ph4P]NO3·CH2Cl2 und [Ph4P]2[SiF6]·CH2Cl2
Authors: Neumüller Bernhard , Dehnicke Kurt
Published: October 2008

Crystal Structures of [Ph3PMe]Cl·CH2Cl2, [Ph4P]NO3·CH2Cl2, and [Ph4P]2[SiF6]·CH2Cl2

The crystal structures of the title compounds are determined by X‐ray diffraction. In all cases, the included dichloromethane molecules as well as the phosphonium cations are involved to form hydrogen bridges with the anions.

[Ph3PMe]Cl·CH2Cl2 (1): Space group $P{\bar 1}$, Z = 2, lattice dimensions at 100 K: a = 890.3(1), b = 988.0(1), c = 1162.5(1) pm, α = 106.57(1)°, β = 91.79(1)°, γ = 92.60(1)°, R1 = 0.0253.

[Ph4P]NO3·CH2Cl2 (2): Space group P21/n, Z = 4, lattice dimensions at 193 K: a = 1057.0(1), b = 1666.0(1), c = 1358.9(1) pm, β = 100.10(1)°, R1 = 0.0359.

[Ph4P]2[SiF6]·CH2Cl2 (3): Space group $P{\bar 1}$, Z = 2, lattice dimensions at 193 K: a = 1063.9(1), b = 1233.1(1), c = 1782.5(2) pm, α = 76.88(1)°, β = 83.46(1)°, γ = 72.29(1)°, R1 = 0.0332.
Tt‐Tt (Tt = Si, Ge) Dumb‐Bell Structures at Different Valence Electron Concentrations: Ln2MgSi2 (Ln = La, Ce), Yb2Li0.5Ge2, and Yb1.75Mg0.75Si2
Authors: Xie Qinxing , Kubata Christof , Wörle Michael , Nesper Reinhard
Published: October 2008

The isostructural compounds Yb2MgSi2, La2.05Mg0.95Si2, and Ce2.05Mg0.95Si2, as well as Yb2Li0.5Ge2 and Yb1.75Mg0.75Si2, respectively, were synthesized from stoichiometric mixtures of the corresponding elements in sealed Nb‐ ampoules under argon atmosphere. The structures were determined by single crystal X‐ray diffraction: Yb2MgSi2 (P4/mbm (No. 127), a = 7.056(1), c = 4.130(1) Å3, Z = 2), La2.05Mg0.95Si2 (P4/mbm, a = 7.544(1), c = 4.464(1) Å3, Z = 2), and Ce2.05Mg0.95Si2 (P4/mbm, a = 7.425(1), c = 4.370(1) Å3, Z = 2), Yb2Li0.5Ge2 (Pnma (No. 62), a = 7.0601(6), b = 14.628(1), c = 7.6160(7) Å, V = 786.5Å3, Z = 4), Yb1.75Mg0.75Si2 (Pnma, a = 6.9796(1), b = 14.4009(1), c = 7.5357(1) Å, V = 757.43(2) Å3, Z = 4). All compounds contain exclusively Tt‐Tt dumb‐bells (Tt = Si, Ge). The Si‐Si Zintl anions exhibit only very small variations of bond lengths which seem to be more due to cation matrix effects than to effective bond orders.
Description of Virus Capsid Structures with Methods from Inorganic Solid State Chemistry
Authors: Andersson Sten
Published: October 2008

The fundamental theorem of algebra and the Hermites provide unique methods to describe virus capsids. Giant virus structures are described in the Rossmann's series that contains the PBCV‐1, and also a hypothetical Mimi virus structure. The HIV core structure given by Mark Yeager and Barbie Ganser‐Pornillos is described as composed of capsid members of the Blue Tongue series.
Homelessness, Mental Illness, and Criminal Activity: Examining Patterns Over Time
Authors: Fischer Sean N. , Shinn Marybeth , Shrout Patrick , Tsemberis Sam
Published: October 2008

This study examined whether street homelessness, sheltered homelessness, and the severity of psychological symptoms predicted non‐violent and violent crime among 207 mentally ill participants who were homeless at baseline. Participants were interviewed at 9 time points over 4 years. Hierarchical linear modeling (HLM) was used to examine whether changes in homelessness status and symptom severity predicted changes in criminal activity over time. Results indicated that homelessness both on the streets and in shelters and psychological symptom severity predicted increases in non‐violent crime. Sheltered homelessness and symptom severity predicted increases in violent crime, although street homelessness did not. A separate mediational analysis with 181 participants showed that the relationship between diagnosis of a psychotic disorder and both non‐violent and violent criminal activity was partially mediated through the severity of psychotic symptoms. Implications for research and intervention are discussed.
Transcobalamin (TC) deficiency—Potential cause of bone marrow failure in childhood
Authors: Prasad C. , Rosenblatt D. S. , Corley K. , Cairney A. E. L. , Rupar C. A.
Published: October 2008

It is unusual for inborn errors of metabolism to be considered in the investigative work‐up of pancytopenia. We report a family in which the proband presented with failure to thrive at 2 months of age and subsequent bone marrow failure. A previous sibling had died at 7 months of age with suspected leukaemia. Haematological findings in the proband were significant for pancytopenia, and bone marrow aspiration showed dysplastic changes in all cell lineages. Urinary organic acid analysis revealed elevated methylmalonic acid. The synthesis of transcobalamin II (transcobalamin, TC) by cultured fibroblasts was markedly reduced, confirming the diagnosis of TC deficiency. The proband and his younger asymptomatic sister (also found to have TC deficiency) were homozygous for R399X (c.1195C>T), a novel mutation resulting in the loss of the C‐ terminal 29 amino acids of TC, a highly conserved region. Response to parenteral vitamin B12 in the proband was dramatic. At 6 years 3 months of age, physical examination is normal and developmental level is age appropriate. His sister is clinically asymptomatic and is also developing normally. Propionylcarnitine concentrations were not elevated in the newborn screening cards from the proband and sister, but that was for specimens retrieved from storage after 7 years and 5 years, respectively. Inherited and acquired cobalamin disorders should both be considered in the differential diagnosis of bone marrow failure syndromes in young children. Early detection of the metabolic causes of bone marrow failure can ensure prompt recovery in some cases involving the vitamin B12 pathway.
Low allelic heterogeneity in a sample of Mexican patients with classical galactosaemia
Authors: Velázquez‐Aragón J. , Alcántara‐Ortigoza M. A. , Vela‐Amieva M. , Monroy S. , Martínez‐Cruz V. , Todd‐Quiñones C. , González‐del Angel A.
Published: October 2008

Classical galactosaemia is an autosomal recessive disease of galactose metabolism caused by a deficiency of the enzyme galactose‐1‐phosphate uridyltransferase (GALT). Galactosaemia is not included in the neonatal screening programme in Mexico and it is necessary to implement methodologies for prompt diagnosis of these patients to establish treatment. To date, more than 190 mutations in the GALT gene have been reported, most in caucasian populations, but there have been no reports of mutations in Latin‐American populations. We report here the mutational spectrum in 19 Mexican galactosaemic patients. The most frequent mutations were p.Q188R, p.N314D and IVS2‐2A>G, which together represented 71% of detected mutations. The mutation IVS2‐2A>G, which has been detected only in Hispanics, was thought to generate a null allele; we identified one patient with a homozygous IVS2‐2A>G mutation who showed a mild deficiency of enzyme value in erythrocytes. One patient homozygous for Duarte 2 (p.N314D, IVS5+62G>A) is probably due to a partial uniparental disomy of chromosome 9. In addition, a novel mutation c.336T>C (p.S112R) was detected in one patient with severe enzymatic deficiency. Despite the small number of patients studied, our results suggest that classical galactosaemia shows low allelic heterogeneity in Mexican patients, in contrast what is observed in other Mendelian disorders such as cystinosis or autosomal dominant hypercholesterolaemia. This low allelic heterogeneity might be explained by a “population of origin” effect in the central region of Mexico, as has been described for phenylketonuria.
Significance of genotype in tetrahydrobiopterin‐responsive phenylketonuria
Authors: Trefz F. K. , Scheible D. , Götz H. , Frauendienst‐Egger G.
Published: October 2008

Background

The value of genotyping to identify tetrahydrobiopterin‐responsive (BH4‐responsive) patients with phenylalanine hydroxylase (PAH) deficiency is a matter of debate.

Methods

We reviewed 250 cases of patients with PAH deficiency, using published data from 198 cases and unpublished data from 52 cases of patients attending our own clinic. Patients underwent analyses for BH4 load and genetic mutations. Partial and full BH4 responses were defined as a 10–29% decrease and a ≥30% decrease from baseline in blood phenylalanine levels, respectively. BH4‐responsive alleles were identified from BH4‐responsive patients as either homozygous for a specific allele or compound heterozygous for that allele with a null mutation.

Results

Most inconsistencies between observed genotype and BH4 response were associated with mutations in the regulatory domain of PAH (p.R68S, p.I65T, p.L48S and p.F39C), where 20/62 alleles (32.2%) were non‐responsive. In the catalytic domain (mutations p.Y414C, p.R261Q, p.E390G, p.A300S, p.R241C, p.A403V and p.V388M), only 8/125 alleles (6.4%) were non‐responsive. Seven patients had a genotype with two BH4‐responsive alleles resulting in no response or only a partial response to BH4. Ten patients had identical genotypes but inconsistent responses in BH4 load.

Conclusions

These results show that BH4 non‐responsiveness is associated with genotype. However, patients with mutations in the regulatory domain show inconsistent results. In patients with two responsive alleles, non‐responsiveness may be related to negative inter‐allelic complementation. In patients with the same genotype and inconsistent results for BH4 load, external factors such as intestinal absorption of BH4, catabolic conditions or other genetic factors may be responsible. Further in vitro studies are necessary to clarify the genotype–phenotype correlation in patients with BH4‐responsive PKU.
Nutritional management of PKU with glycomacropeptide from cheese whey
Authors: Ney D. M. , Gleason S. T. , van Calcar S. C. , MacLeod E. L. , Nelson K. L. , Etzel M. R. , Rice G. M. , Wolff J. A.
Published: October 2008

Individuals with phenylketonuria (PKU) must follow a lifelong low‐phenylalanine (Phe) diet to prevent neurological impairment. Compliance with the low‐Phe diet is often poor owing to restriction in natural foods and the requirement for consumption of a Phe‐free amino acid formula or medical food. Glycomacropeptide (GMP), a natural protein produced during cheese‐making, is uniquely suited to a low‐Phe diet because when isolated from cheese whey it contains minimal Phe (2.5–5 mg Phe/g protein). This paper reviews progress in evaluating the safety, acceptability and efficacy of GMP in the nutritional management of PKU. A variety of foods and beverages can be made with GMP to improve the taste, variety and convenience of the PKU diet. Sensory studies in individuals with PKU demonstrate that GMP foods are acceptable alternatives to amino acid medical foods. Studies in the PKU mouse model demonstrate that GMP supplemented with limiting indispensable amino acids provides a nutritionally adequate source of protein and improves the metabolic phenotype by reducing concentrations of Phe in plasma and brain. A case report in an adult with classical PKU who followed the GMP diet for 10 weeks at home indicates safety, acceptability of GMP food products, a 13–14% reduction in blood Phe levels (p < 0.05) and improved distribution of dietary protein throughout the day compared with the amino acid diet. In summary, food products made with GMP that is supplemented with limiting indispensable amino acids provide a palatable alternative source of protein that may improve dietary compliance and metabolic control of PKU.
Progress in expanded newborn screening for metabolic conditions by LC‐MS/MS in Tuscany: Update on methods to reduce false tests
Authors: la Marca G. , Malvagia S. , Casetta B. , Pasquini E. , Donati M. A. , Zammarchi E.
Published: October 2008

We report on our 6‐year experience of expanded newborn screening by tandem mass spectrometry in Tuscany (Italy), the first Italian Region to screen all newborns for more than 40 inborn errors of metabolism: organization, diseases observed and updates on methods to reduce false‐positive and false‐negative tests are described. Blood collection is recommended between 48 and 72 h of life. Blood spots are sent daily by courier to laboratory. When a positive result occurs, two subsequent procedures are followed: for disorders with possible acute metabolic decompensation, the baby is immediately recalled and clinical examinations and confirmatory tests are performed; for the other disorders, the nursery provides for a second blood spot. If the test is positive, clinical examinations and confirmatory tests are performed. In both cases, if confirmatory tests are positive, a treatment and a follow‐up programme are started. Up to now, spots from 160 000 infants have been analysed and 80 affected patients have been identified (disorders of amino acids, organic acids and fatty acids metabolism). We describe adjustments to cut‐off values, the introduction of a second‐tier test for propionic acidaemia and for methylmalonic aciduria, the inclusion of succinylacetone in the panel of metabolites, and protocols for premature infants and for newborns on parenteral nutrition or transfused. These changes resulted in a reduction in recalls from 1.37% to 0.32% and consequently of working time and parental stress. Avoiding false‐negatives by using more specific markers and minimizing the false‐positive rate with second‐tier testing is important for a successful newborn screening programme.
Quality of life in noncompliant adults with phenylketonuria after resumption of the diet
Authors: Bik‐Multanowski M. , Didycz B. , Mozrzymas R. , Nowacka M. , Kaluzny L. , Cichy W. , Schneiberg B. , Amilkiewicz J. , Bilar A. , Gizewska M. , Lange A. , Starostecka E. , Chrobot A. , Wojcicka‐Bartlomiejczyk B. I. , Milanowski A.
Published: October 2008

Background:

Discontinuation of dietary therapy in adults with phenylketonuria can lead to neuropsychological abnormalities and emotional problems. The aim of our study was to assess the change in quality of life in adult patients returning to the diet and to define the reasons for failure in diet resumption.

Methods:

Quality of life was assessed by means of the Psychological General Well‐Being Index before study entry and subsequently after 3 and 9 months. Reasons for failure in diet resumption were analysed.

Results:

53 patients participated in the study. Initial quality of life assessment revealed severe distress in 17%, moderate distress in 28% and positive well‐being in 55% of them. In the majority of patients with severe or moderate distress, improvement of subjective well‐being was observed (especially in the domains of anxiety and depressiveness) if they managed to return to the diet (blood phenylalanine concentrations before study entry 0.78–1.62 mmol/L, mean 1.16 mmol/L; average blood phenylalanine concentration decrease by 0.42 mmol/L). Only 29 persons managed to maintain the diet for at least 3 months and only 10 participants finished the entire 9‐month study protocol. Problems with dietary treatment while at work, the high cost of low‐protein products and poor knowledge regarding proper diet were the most important factors responsible for failure in resumption of diet.

Conclusion:

Interpersonal differences exist between adult patients on relaxed diet, in some of whom quality of life often remains good, while others can suffer from severe emotional distress. Returning to diet increases quality of life in the majority of patients.
A Systematic Review of the Effects of Disclosing Carrier Results Generated Through Newborn Screening
Authors: Hayeems R. Z. , Bytautas J. P. , Miller F. A.
Published: October 2008

Evidence on the effects of disclosing carrier results identified through newborn screening (NBS) is needed to develop effective strategies for managing these results, and to inform debate about contradictory policies governing genetic testing in minors in the context of NBS relative to clinical care. This is likely to be even more important as technological opportunities for carrier identification through NBSincrease. We report the results of a systematic review of evidence related to the generation of carrier results through NBS to summarize what is known about: (1) the outcomes associated with these results; (2) the best strategies for providing information and follow‐up care to parents; and (3) the impact they have on reproductive decision‐making. Our study expands the existing body of knowledge and identifies gaps in the evidence base. As key players in the management of carrier results clinically, genetic counselors are well positioned to engage in formative research and policy development in this area.
Association of Ilizarov's technique and intramedullary rodding in the treatment of congenital pseudarthrosis of the tibia
Authors: Mathieu Laurent , Vialle Raphaël , Thevenin-Lemoine Camille , Mary Pierre , Damsin Jean-Paul
Published: October 2008

Purpose

Many surgical techniques have been published on how to treat congenital pseudoarthrosis of the tibia (CPT). We combined Ilizarov's fixator with intramedullary nailing of the tibia and developed a procedure which combines the advantages of both methods: Ilizarov's high fusion rate with alignment control and the protection against refracture provided by the intramedullary nail. The results of this approach are presented and discussed.

Material and methods

Seven boys and three girls aged 3–14 years (mean age 8 years 2 months) were treated using our combined technique. In six cases, the CPT was associated with neurofibromatosis. Two strategies were adopted: in six cases, a compression was applied on the bone defect, and in four cases, segmental bone transportation was performed before the compression procedure. The final follow-up (1.2–6.6 years) included a clinical and radiological examination.

Results

Tibial union was achieved in nine cases without bone grafting. In one case, tibial union still remains uncertain, despite intertibiofibular bone grafting and additional compression procedures. Thirteen overall complications were noted, including three valgus deformity of the ankle. Bone transportation failed to achieve complete limb lengthening in three cases. One deep infection occurred 4 years after removal of the external fixator. The treatment for this included nail removal and antibiotic therapy for 3 months. Despite a permanent protection of orthosis, a refracture occurred 2 years after nail removal, reverting to the initial level of pseudarthrosis. Another surgical attempt using the same method was then performed with a satisfactory result.

Conclusions

The association of Ilizarov's technique and intramedullary nailing achieved and maintained tibial union in nine of ten patients at final follow-up. It also allowed correction of axial deformities and prevented refracture. Despite the short duration of the follow-up and a high rate of complications in our series, this method can be useful in many cases of CPT in which healing has failed to occur despite many previous surgeries.
Pathologic fractures of long bones in Nigerian children
Authors: Akinyoola Akinyele Lawrence , Orimolade Elkanah Ayodele , Yusuf Moruf Babatunde
Published: October 2008

Background

Pathologic or spontaneous fractures are recognised causes of morbidity in children. There is a paucity of data on their aetiology and patterns in African children.

Methods

A combined retrospective and prospective study of 47 children aged 15 and below with pathologic fractures of long bones seen from January 2000 to December 2006. The setting was the Orthopaedic and Traumatology department of the Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Nigeria.

Results

A total of 47 patients with a mean age of 5.3 years ± SD with pathologic fractures of 50 long bones were seen and treated. The most commonly affected bones were the femur (28%), tibia (28%) and humerus (26%). Chronic osteomyelitis following inadequately treated acute haematogenous osteomyelitis was the commonest cause of pathologic fractures (74.5%). The mean duration of fracture union was 6.8 ± 2.3 months and the outcome was satisfactory in 91.4% of cases.

Conclusions

The aetiology of pathologic fractures in the African population is different from their causes in Caucasian children. Chronic osteomyelitis following inadequately treated acute haematogenous osteomyelitis continues to plague many children in our environment.
Differential analgesic effects of morphine and gabapentin on behavioural measures of pain and disability in a model of osteoarthritis pain in rats
Authors: Vonsy Jean Laurent , Ghandehari Javid , Dickenson Anthony Henry
Published: October 2008

Osteoarthritis (OA) is associated with chronic debilitating joint pain. Pain is the result of an emotional and sensory experience and preclinical models of OA can thus be useful to better understand the underlying mechanisms of the disease and test new therapeutic options.

We induced unilateral knee OA in Sprague‐Dawley rats using monosodium iodoacetate (MIA), a glycolysis inhibitor and assessed the effects of acute and chronic morphine and gabapentin using a battery of quantitative behavioural outcome measures of pain and disability.

Animals received a single intra‐articular injection of 2mg MIA in 25μl saline, causing inflammation and progressive cartilage degradation. Mechanical and thermal sensitivity as well as ambulatory‐evoked pain were then monitored using von Frey hairs, acetone and a rotarod. Once maximum nociceptive responses were reached, chronic bi‐daily morphine (3mg/kg s.c.) or gabapentin (30mg/kg s.c.) were administered for 5 days.

We observed a marked biphasic mechanical hypersensitivity that increased and reached a plateau from day 14 (317.6% of control response, p<0.01, with von Frey 6g). Moreover we found a marked cooling hypersensitivity, and validated a novel ambulatory‐evoked pain score. These measures were significantly reduced after both acute (13.3% of sham response, p<0.01, von Frey 6g) and chronic (38.3%, p<0.05) morphine whilst only chronic gabapentin (37.0%, p<0.05) had an effect.

We show the reliability of the model in terms of mechanical hypersensitivity and demonstrate cooling hypersensitivity and ambulatory‐evoked pain. In terms of translational research, the effects of morphine and gabapentin validate the model and suggest trials of these therapeutic approaches in OA patients.
Glu43 is an essential residue for coordinating the [Fe2S2] cluster of IscR from Acidithiobacillus ferrooxidans
Authors: Zeng Jia , Zhang Xiaojian , Wang Yiping , Ai Chenbing , Liu Qing , Qiu Guanzhou
Published: October 2008

The iron–sulfur cluster regulator (IscR) was reported to be a repressor of the iscRSUA operon. In vitro transcription reactions revealed that the IscR had a repression effect on the iscR promoter. The IscR contains a [Fe2S2] cluster per each monomer, and three highly conserved cysteines were identified to ligate the [Fe2S2] cluster. It was proposed that a non‐cysteine residue might be the fourth ligand for the [Fe2S2] cluster. In this study, using site‐directed mutagenesis, Glu43 was found to be the fourth residue that coordinates the [Fe2S2] cluster of IscR.