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Chicken is a major food source for humans, hence it is important to understand the mechanisms involved in nutrient absorption in chicken. In the gastrointestinal tract (GIT), the microbiota plays a central role in enhancing nutrient absorption and strengthening the immune system, thereby affecting both growth and health of chicken. There is little information on the diversity and functions of chicken GIT microbiota, its impact on the host, and the interactions between the microbiota and host. Here, we review the recent metagenomic strategies to analyze the chicken GIT microbiota composition and its functions related to improving metabolism and health. We summarize methodology of metagenomics in order to obtain bacterial taxonomy and functional inferences of the GIT microbiota and suggest a set of indicator genes for monitoring and manipulating the microbiota to promote host health in future. [ABSTRACT FROM AUTHOR]

BICEP2 has observed a primordial gravitational wave corresponding to the tensor-to-scalar ratio of 0.16. It seems to require a super-Planckian inflationary model. In this paper, we propose a double hybrid inflation model, where the inflaton potential dynamically changes with the evolution of the inflaton fields. During the first phase of inflation over 7 e-folds, the power spectrum can be almost constant by a large linear term in the hybrid potential, which is responsible also for the large tensor-to-scalar ratio. In the second phase of 50 e-folds, the dominant potential becomes dynamically changed to the logarithmic form as in the ordinary supersymmetric hybrid inflation, which is performed by the second inflaton field. In this model, the sub-Planckian field values (~0.9 M_P) can still yield the correct cosmic observations with the sufficient e-folds. [ABSTRACT FROM AUTHOR]

The compound [Ni(L)(isoph)2][Ni(L)].8H2O (1; L = C-meso-5,5,7,12,12,14- hexamethyl-1,4,8,11-tetraazacyclotetradecane; H2-isoph = isophthalic acid) has been synthesized and structurally characterized. Complex 1 exhibits a geometrically symmetric core with a {4/6} coordination number set. The coordination environment around the Ni(1) ion is a distorted octahedron, while the geometry around the four-coordinate Ni(2) is depicted as square planar in 1D hydrogen-bonded infinite chain. The compound crystallizes in the triclinic system P-1 with a = 8.602(2), b = 10.684(7), c = 16.550(3) Å, α = 91.04(4), β = 94.09(2), Å = 111.09(4)°, V = 1413.9(10) Å3, Z = 1. The cyclic voltammogram of 1 undergoes one-electron wave corresponding to NiII/NiI process. The electronic spectra, electrochemical and TGA behavior of the complex are significantly affected by the nature of the hexamethyltetraaza macrocycle and the axial isoph2- ligand. [ABSTRACT FROM AUTHOR]

The reaction of [Ni(L)]Cl2·2H2O (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo [14,4,01.18,07.12]docosane) with trans-1,2-cyclopentanedicarboxylic acid (H2-cpdc) yields a 1D hydrogen-bonded infinite chain with formula [Ni(L)(H-cpdc-)2] (1). This complex has been characterized by X-ray crystallography, spectroscopy and cyclic voltammetry. The crystal structure of 1 exhibits a distorted octahedral geometry about Ni atom with four nitrogen atoms of the macrocycle and two oxygen atoms of the H-cpdc- ligand at the axial position. Compound 1 crystallizes in the monoclinic system P21/c with a = 8.7429(17), b = 10.488(2), c = 18.929(4) Å, β = 91.82(2), V = 1734.8(6) Å3, Z = 2. Electronic spectrum of 1 reveals a high-spin octahedral environment. Cyclic voltammetry of 1 undergoes two waves of a one-electron transfer corresponding to NiII/NiIII and NiII/NiI processes. [ABSTRACT FROM AUTHOR]

The reaction of [Ni(L)]Cl2·2H2O (L = 3.14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18,07.12]docosane) with malonic (H2mal) acid yields a one-dimensional coordination polymer [Ni(L)(mal)2]n ( 1). The structure was characterized by X-ray crystallography, spectroscopic and magnetic susceptibility. Each nickel(II) ion has a distorted octahedral coordination environment with the four secondary amines of the macrocycle in which two carboxylate anions of the malonate ligand have assembled around each nickel center. The compound crystallizes in the monoclinic system C2/ c with a = 19.487(4), b = 8.4143(12), c = 14.6036(18) Å, β = 102.232(11)°, V = 2340.2(6) Å3, Z = 4. Electronic spectrum of 1 exhibits a high-spin octahedral environment. The magnetic behavior of 1 reveals a weak intramolecular antiferromagnetic interaction with J values of −1.91(1) cm−1. The cationic units in complex 1 are bridged by carboxylate anions to give a one-dimensional coordination polymer in which each nickel(II) ion has a distorted octahedral coordination environment.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Escherichia coli cells expressing Rhodococcus DK17 o-xylene dioxygenase genes were used for bioconversion of m-xylene. Gas chromatography–mass spectrometry analysis of the oxidation products detected 3-methylbenzylalcohol and 2,4-dimethylphenol in the ratio 9:1. Molecular modeling suggests that o-xylene dioxygenase can hold xylene isomers at a kink region between α6 and α7 helices of the active site and α9 helix covers the substrates. m-Xylene is unlikely to locate at the active site with a methyl group facing the kink region because this configuration would not fit within the substrate-binding pocket. The m-xylene molecule can flip horizontally to expose the meta-position methyl group to the catalytic motif. In this configuration, 3-methylbenzylalcohol could be formed, presumably due to the meta effect. Alternatively, the m-xylene molecule can rotate counterclockwise, allowing the catalytic motif to hydroxylate at C-4 yielding 2,4-dimethylphenol. Site-directed mutagenesis combined with structural and functional analyses suggests that the alanine-218 and the aspartic acid-262 in the α7 and the α9 helices play an important role in positioning m-xylene, respectively. [ABSTRACT FROM AUTHOR]

We review models which generate a large non-Gaussianity of the local form. We first briefly consider three models which generate the non-Gaussianity either at or after the end of inflation; the curvaton scenario, modulated (p)reheating, and an inhomogeneous end of inflation. We then focus on ways of generating the non-Gaussianity during inflation. We derive general conditions which a product or sum separable potential must satisfy in order to generate a large local bispectrum during slow-roll inflation. As an application, we consider two-field hybrid inflation. We then derive a formalism not based on slow roll which can be applied to models in which the slow-roll parameters become large before inflation ends. An exactly soluble two-field model is given in which this happens. Finally, we also consider further non-Gaussian observables, a scale dependence of fNL and the trispectrum. [ABSTRACT FROM AUTHOR]

Abstract  The reaction of [M(L)]Cl2 · 2H2O (M = Ni2+ and Cu2+, L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18,07.12]docosane) with 1,1-cyclobutanedicarboxylic acid (H2-cbdc) generates 1D and 2D hydrogen-bonded infinite chains [Ni(L)(H-cbdc−)2] (1) and [Cu(L)(H-cbdc−)2] (2). (H-cbdc− = cyclobutane-1-carboxylic acid-1-carboxylate). These complexes have been characterized by X-ray crystallography, spectroscopy, and cyclic voltammetry. The crystal structure of 1 shows a distorted octahedral coordination geometry around the nickel(II) ion, with four secondary amines and two oxygen atoms of the H-cbdc− ligand at the trans position. In 2, the coordination environment around the central copper(II) ion shows a Jahn–Teller distorted octahedron with four Cu–N bonds and two long Cu–O distances. The cyclic voltammogram of the complexes undergoes two one-electron waves corresponding to MII/MIII and MII/MI processes. The electronic spectra and electrochemical behavior of the complexes are significantly affected by the nature of the axial H-cbdc− ligand. [ABSTRACT FROM AUTHOR]

Abstract  The tridentate Schiff base carboxylate-containing ligand 2-pyridylmethylamino-3-butyric acid (Hpaba) reacts with copper(II) perchlorate to give the one-dimensional chain complex {[Cu(μ-paba)](ClO4)·H2O} n (1). The coordination geometry of each copper(II) ion is best described as a square-plane with two nitrogen atoms and one carboxylate oxygen atom of the ligand, and one carboxylate oxygen atom belong to another ligand. It crystallizes in the monoclinic system P21/c with a = 12.717(2), b = 7.9163(15), c = 14.981(2) Å, β = 111.14(1)°, V = 1406.8(4) Å3, Z = 4. Cyclic voltammogram of 1 undergoes the reversible one-electron oxidation to the Cu(III) and the reversible one-electron reduction to the Cu(I) state. Graphical Abstract  Crystal structure of 1 reveals a syn-anti carboxylate-bridged one dimensional chain complex in which the coordination environment around each copper(II) ion exhibits a distorted square plane. [ABSTRACT FROM AUTHOR]

Abstract  These complexes have been characterized by X-ray crystallography, spectroscopic, and cyclic voltammetry. In 1, the copper(II) ion has a distorted square-pyramidal geometry with three nitrogen atoms of the dpa ligand and two oxygen atoms of the nitrate anions. The crystal structure of 2 shows that the copper(II) ions are bridged by tp anion to form a dinuclear complex, in which each copper(II) ion exhibits a distorted square-pyramid with three nitrogen atoms of the dpa ligand, water molecule, and the oxygen atom of the bridging tp ligand. Cyclic voltammetric data indicate that 1 undergoes irreversible one-electron oxidation to the CuIII and reversible one-electron reduction to the CuI, while 2 gives one reversible oxidation and two reversible and irreversible reduced processes. The electronic spectra and redox potentials of the complexes are influenced significantly by the anionic ligands. Graphical Abstract  The reaction of [Cu(dpa)Cl2] with K(NO3)2 and Na2tp yields mononuclear and dinuclear copper(II) complexes [Cu(dpa)(NO3)2] (1) and [Cu2(dpa)2(H2O)2(μ-tp)](tp)�6H2O (2) (dpa = di-(2-picolyl)amine, tp = terephthalate). [ABSTRACT FROM AUTHOR]

Abstract  The reaction of cobalt(II) chloride with the tridentate ligand 2-oximino-3-thiosemicarbazone-2,3-butanedione [Hotsb (1)] leads to the formation of the novel six-coordinated complex [Co(otsb)2]·2H2O (2). This complex has been synthesized and characterized by X-ray crystallography, spectroscopic and cyclic voltammetric measurements. The ligand Hotsb (1) obtained by the condensation of 2,3-butanedione monoxime and thiosemicarbazide is used for the preparation of complex 2. The Hotsb (1) crystallizes into a monoclinic lattice with space group P21/c. The crystal structure of 2 shows a distorted mer-octahedral geometry in which the ligands are coordinated as uninegatively charged tridentate chelating agents via the hydrazine nitrogen atoms, the azomethine nitrogen atoms, and the thiolate sulfur atoms. The cyclic voltammogram of 2 undergoes two irreversible one-electron waves corresponding to CoII/CoIII and CoII/CoI processes. [ABSTRACT FROM AUTHOR]

Abstract  The reaction of Cu(ClO4)2�6H2O and Cd(ClO4)2 with di-(2-picolyl)sulfur (dps) leads to the formation of mononuclear complexes [Cu(dps)(H2O)(ClO4)](ClO4) (1) and [Cd(dps)2](ClO4)2 (2). The crystal structure of 1 exhibits a distorted square pyramidal geometry, coordinated by one sulfur and two nitrogen atoms from the dps ligand, one water molecule and one perchlorate oxygen atom. For 2, the environment around cadmium atom is in a distorted octahedron with four nitrogen and two sulfur atoms from the dps ligand. Cyclic voltammetric data show that complexes undergo two waves of a one-electron transfer corresponding to M(II)/M(III) and M(II)/M(I) processes. Spectral and electrochemical behaviors of the complexes are also discussed. [ABSTRACT FROM AUTHOR]

We consider axino warm dark matter in a supersymmetric axion model with R-parity violation. In this scenario, axino with the mass ma ≃7 keV can decay into photon and neutrino resulting in the X-ray line signal at 3.5keV, which might be the origin of unidentified X-ray emissions from galaxy clusters and Andromeda galaxy detected by the XMM-Newton X-ray observatory. [ABSTRACT FROM AUTHOR]

Giant magnetic flux jumps are observed in magnetic hysteresis loops of Ba0.6K0.4Fe2As2 single crystals. The size of the flux jumps, which appear only at low temperatures (T<4 K), is so large that it can transform the whole superconducting state into the normal state. The recovery rate to the superconducting state is rather slow, although the superconducting state is almost fully recovered. We show that theoretical predictions based on the adiabatic approach with nonlocal electrodynamics give a good explanation of the flux jumps observed in the single crystals of Ba0.6K0.4Fe2As2. [ABSTRACT FROM AUTHOR]

Purpose BVAC-B is an autologous B cell- and monocyte-based immunotherapeutic vaccine that contains cells transfected with a recombinant human epidermal growth factor receptor 2 (HER2) gene and loaded with the natural killer T cell ligand alpha-galactosylceramide. Here, we report the first BVAC-B study in patients with HER2-positive advanced gastric cancer. Materials and Methods Patients with advanced gastric cancer refractory to standard treatment with HER2+ immunohistochemistry ≥ 1 were eligible for treatment. Patients were administered low (2.5×107 cells/dose), medium (5.0×107 cells/dose), or high dose (1.0×108 cells/dose) of BVAC-B intravenously four times every 4 weeks. Primary endpoints included safety and maximum tolerated BVAC-B dose. Secondary endpoints included preliminary clinical efficacy and BVAC-B-induced immune responses. Results Eight patients were treated with BVAC-B at low (n=1), medium (n=1), and high doses (n=6). No dose-limiting toxicity was observed, while treatment-related adverse events (TRAEs) were observed in patients treated with medium and high doses. The most common TRAEs were grade 1 (n=2) and grade 2 (n=2) fever. Out of the six patients treated with high-dose BVAC-B, three had stable disease with no response. Interferon gamma, tumor necrosis factor-α, and interleukin-6 increased after BVAC-B treatment in all patients with medium and high dose, and HER2-specific antibody was detected in some patients. Conclusion BVAC-B monotherapy had a safe toxicity profile with limited clinical activity; however, it activated immune cells in heavily pretreated patients with HER2-positive gastric cancer. Earlier treatment with BVAC-B and combination therapy is warranted for evaluation of clinical efficacy. [ABSTRACT FROM AUTHOR]

Silicon (Si) alone or Si + boron (B) foliar sprays at the maturity stage of light red of the cherry tomato cultivar 'Unicorn' were examined to determine the effect on the quality and shelf life. The foliar applications that were utilized in this study were: 20 mM Si alone from silicon dioxide (SiO2), 20 mM Si from SiO2 with 4.85 mM B from boric acid (H3BO3) and distilled water as a control substance. The Si + B treatment resulted in the lowest respiration and ethylene production as recorded. The Si + B treated tomato fruits attained and retained the highest firmness as noted. Compared with the control, the Si + B treated fruits had less-soluble solids, higher titratable acidity, higher vitamin C content, and longer shelf life. The Si + B treated fruits and leaves had the highest Si and B content uptake. Therefore, Si + B foliar sprays increased and retained cherry tomato firmness, maintained soluble solids, maintained titratable acidity, increased the vitamin C content, prolonged shelf life, increased cellwall compactness, and increased Si and B accumulation as noted in the study. [ABSTRACT FROM AUTHOR]

In the title compound, [Cu3(C10H13N2O2)2Cl(ClO4)3(H2O)3]·2H2O, the Cu atoms exhibit octa­hedral, square-pyramidal and square-planar coordination environments, and they are linked by carboxyl­ate groups to form a trinuclear structure. The five water mol­ecules participate in intra- and inter­molecular hydrogen bonding. [ABSTRACT FROM AUTHOR]

The tetra­dentate Schiff base carboxyl­ate-containing ligand bis­(2-pyridylmeth­yl)amino-6-caproic acid (Hpmca) reacts with zinc(II) perchlorate to give the title one-dimensional zinc(II) complex, {[Zn(C18H22N3O2)(H2O)](ClO4)} n or {[Zn(μ-pmca)(H2O)](ClO4)} n. Each ZnII ion has a distorted octa­hedral geometry, being coordinated by three N atoms of the ligand, two O atoms belonging to another ligand, and one water mol­ecule. [ABSTRACT FROM AUTHOR]

Non-Hodgkin's lymphoma (NHL), a disease which may involve the spine, is frequently associated with advanced disease. Radiculopathy caused by spinal root compression as the initial presentation in patients with NHL is very rare and thought to occur in less than 5% of cases. A 69-year-old woman complained of a history of low back pain with right sciatica for 1 month prior to admission. Computed tomography and magnetic resonance imaging of the lumbar spine showed a dumbbell-shape epidural mass lesion extending from L2 to L3, which was suggestive of a neurogenic tumor. After paraspinal approach and L2 lower half partial hemilaminectomy, total excision of the tumor was achieved, followed by rapid improvement of back pain and radiating pain. The lesion was confirmed to be Burkitt's lymphoma by histopathological examination. We then checked whole-body PET-CT, which showed multifocal malignant lesions in the intestine, liver, bone and left supraclavicular lymph node. Although a rare situation, Burkitt's lymphoma should be considered in the differential diagnosis for patients presenting with back and lumbar radicular pain without a prior history of malignancy. Burkitt's lymphoma could be the cause of dumbbell-shape spinal tumor. [ABSTRACT FROM AUTHOR]

The metabolically versatile Rhodococcus sp. strain DK17 is able to grow on tetralin and indan but cannot use their respective desaturated counterparts, 1,2-dihydronaphthalene and indene, as sole carbon and energy sources. Metabolite analyses by gas chromatography-mass spectrometry and nuclear magnetic resonance spectrometry clearly show that (i) the meta-cleavage dioxygenase mutant strain DK180 accumulates 5,6,7,8-tetrahydro-1,2-naphthalene diol, 1,2-indene diol, and 3,4-dihydro-naphthalene-1,2-diol from tetralin, indene, and 1,2-dihydronaphthalene, respectively, and (ii) when expressed in Escherichia coli, the DK17 o-xylene dioxygenase transforms tetralin, indene, and 1,2-dihydronaphthalene into tetralin cis-dihydrodiol, indan-1,2-diol, and cis-1,2-dihydroxy-1,2,3,4-tetrahydronaphthalene, respectively. Tetralin, which is activated by aromatic hydroxylation, is degraded successfully via the ring cleavage pathway to support growth of DK17. Indene and 1,2-dihydronaphthalene do not serve as growth substrates because DK17 hydroxylates them on the alicyclic ring and further metabolism results in a dead-end metabolite. This study reveals that aromatic hydroxylation is a prerequisite for proper degradation of bicyclics with aromatic and alicyclic rings by DK17 and confirms the unique ability of the DK17 o-xylene dioxygenase to perform distinct regioselective hydroxylations. [ABSTRACT FROM AUTHOR]

Chromohalobacter sp. strain HS-2 was isolated from salted fermented clams and analyzed for the ability to grow on benzoate and p-hydroxybenzoate as the sole carbon and energy source. HS-2 was characterized as moderately halophilic, with an optimal NaCl concentration of 10%. The genes encoding the benzoate metabolism were cloned into a cosmid vector, sequenced, and then analyzed to reveal the benzoate ( benABCD) and catechol ( catBCA) catabolic genes, both of which are flanked on either side by LysR-type transcriptional regulator ( catR) and membrane transport protein for benzoate ( benE) in the gene order catRBCAbenABCDE. Near the large cat- ben cluster, a p-hydroxybenzoate hydroxylase gene ( pobA) and two putative regulatory genes ( pcaQ and pobR) were additionally detected. The HS-2 genes involved in benzoate and p-hydroxybenzoate degradation are tightly clustered within a c. 19 kb region, and show quite a different genetic organization from those of other benzoate catabolic genes. Reverse transcriptase-PCR experiments show that benzoate induces the expression of benzoate 1,2-dioxygenase, catechol 1,2-dioxygenase, and protocatechuate 3,4-dioxygenase while p-hydroxybenzoate only induced the expression of p-hydroxybenzoate hydroxylase. When expressed in Escherichia coli, benzoate 1,2-dioxygenase (BenABC) and p-hydroxybenzoate hydroxylase (PobA) transformed benzoate and p-hydroxybenzoate into cis-benzoate dihydrodiol and protocatechuate, respectively. [ABSTRACT FROM AUTHOR]

We identified a p-cumate degrading gene cluster (designated cmt) with a novel organization in our genomic studies of the terpene-degrading Rhodococcus sp. strain T104. The mutant strain SN140, isolated for the inability to grow on p-cumate, accumulates 2,3-dihydroxy- p-cumate as identified by liquid chromatography-mass spectrometry and 300 MHz proton nuclear magnetic resonance spectroscopy. Reverse transcriptase polymerase chain reaction experiments showed that the cmt genes are operonic and induced specifically by growth on p-cumate. This report is the first example of identifying the genes for p-cumate degradation in a gram-positive organism based on functional data. [ABSTRACT FROM AUTHOR]

Conventional cancer targeting with nanoparticles has been based on the assumed enhanced permeability and retention (EPR) effect. The data obtained in clinical trials to date, however, have rarely supported the presence of such an effect. To address this challenge, we formulated intracellular nitric oxide-generating nanoparticles (NO-NPs) for the tumor site-specific delivery of NO, a well-known vasodilator, with the intention of boosting EPR. These nanoparticles are self-assembled under aqueous conditions from amphiphilic copolymers of poly(ethylene glycol) and nitrated dextran, which possesses inherent NO release properties in the reductive environment of cancer cells. After systemic administration of the NO-NPs, we quantitatively assessed and visualized increased tumor blood flow as well as enhanced vascular permeability than could be achieved without NO. Additionally, we prepared doxorubicin (DOX)-encapsulated NO-NPs and demonstrated consequential improvement in therapeutic efficacy over the control groups with considerably improved DOX intratumoral accumulation. Overall, this proof of concept study implies a high potency of the NO-NPs as an EPR enhancer to achieve better clinical outcomes. [ABSTRACT FROM AUTHOR]

Although sonodynamic therapy (SDT) has emerged as a potential alternative to conventional photodynamic therapy, the low quantum yield of the sonosensitizer such as TiO2 nanoparticles (NPs) is still a major concern. Here, we have developed hydrophilized Au-TiO2 nanocomposites (HAu-TiO2 NCs) as sonosensitizers for improved SDT. The physicochemical properties of HAu-TiO2 NCs were thoroughly studied and compared with their counterparts without gold deposition. Upon exposure of HAu-TiO2 NCs to ultrasound, a large quantity of reactive oxygen species (ROS) were generated, leading to complete suppression of tumor growth after their systemic administration in vivo. Overall, it was evident that the composites of gold with TiO2 NPs significantly augmented the levels of ROS generation, implying their potential as SDT agents for cancer therapy. [ABSTRACT FROM AUTHOR]

We report the growth of Ba1–xLaxSnO3 (x=0.00, 0.005, 0.01, 0.02, and 0.04) thin films on the insulating BaSnO3(001) substrate by pulsed laser deposition. The insulating BaSnO3 substrates were grown by the Cu2O-CuO flux, in which the molar fraction of KClO4 was systematically increased to reduce electron carriers and thus induce a doping induced metal-insulator transition, exhibiting a resistivity increase from ~10–3 to ~1012Ωcm at room temperature. We find that all the Ba1–xLaxSnO3 films are epitaxial, showing good in-plane lattice matching with the substrate as confirmed by X-ray reciprocal space mappings and transmission electron microscopy studies. The Ba1–xLaxSnO3 (x=0.005–0.04) films showed degenerate semiconducting behavior, and the electron mobility at room temperature reached 100 and 85 cm2V–1 s–1 at doping levels 1.3×1020 and 6.8×1019 cm–3, respectively. This work demonstrates that thin perovskite stannate films of high quality can be grown on the BaSnO3(001) substrates for potential applications in transparent electronic devices. [ABSTRACT FROM AUTHOR]

Surgical decompression for cervical radiculopathy includes anterior cervical discectomy and fusion, anterior or posterior cervical foraminotomy, and cervical arthroplasty after decompression. The aim of this study was to evaluate the usefulness of a CO2 laser in posterior-approach surgery for unilateral cervical radiculopathy. From January 2006 to December 2008, 12 consecutive patients with unilateral cervical radiculopathy from either foraminal stenosis or disc herniation, which was confirmed with imaging studies, underwent posterior foraminotomy and discectomy with the use of a microscope and CO2 laser. For annulotomy and discectomy, we used about 300 joules of CO2 laser energy. Magnetic resonance imaging (MRI) was used to evaluate the extent of disc removal or foraminal decompression. Clinical outcome was evaluated by using visual analogue scale scores for radicular pain and Odom's criteria. For evaluation of spinal stability, cervical flexion and extension radiographs were obtained. Single-level foraminotomy was performed in 10 patients and two-level foraminotomies were performed in 2 patients. Preoperative radicular symptoms were improved immediately after surgery in all patients. No surgery-related complications developed in our cases. Postoperative MRI demonstrated effective decompression of ventral lesions and widened foraminal spaces in all cases. There was no development of cervical instability during the follow-up period. Posterior foraminotomy and discectomy using a microscope and CO2 laser is an effective surgical tool for unilateral cervical radiculopathy caused by lateral or foraminal disc herniations or spondylotic stenosis. Long-term follow- up with radiographs showed no significant kyphotic changes or spinal instability. [ABSTRACT FROM AUTHOR]

Manganese(Il/lII) complexes of a phenol-based tetradentate ligand L[sup2-] [H[sub2]L = N,N'-dimethyl-N,N'-bis(2-hydroxy- 3,5-dimethylbenzyl)-ethylenediamine], namely, [Mn[sub4](L)[sub2](PhCOO)[sub6]] (1), [Mn[sub3](L)[sub2](CH[sub3]CH[sub2]COO)[sub2](OMe)[sub2]]∙H[sub2]O (2), and [Mn(L)((CH[sub3])[sub3]CCOO)(CH[sub3]OH)]∙CH[sub3]OH (3), have been synthesized. The basicity and steric congestion provided by the carboxylate moiety used as an ancillary ligand have profound influence on tuning the nuclearity of these compounds. Results of X-ray crystallography, electronic spectroscopy, and variable-temperature (1.8-300 K) magnetic measurements have been used to characterize these compounds. Complex 1 has a very interesting centrosymmetric structure that involves two crystallographically equivalent binuclear [Mn[supII]—Mn[supIII]] units, connected together by a pair of syn—anti bridging benzoates to generate a "dimer of dimers" structural motif. Compound 2 with propionate as the ancillary ligand, on the other hand, has a nearly linear Mn[supIII]—Mn[supII]—Mn[supIII] core with antiferromagnetically coupled (J = -0.13 cm[sup-1]) metal centers. Compound 1 has an S[subT] = 9 spin ground state with ferromagneticlly coupled metal centers (J[subwb]= 2.8(1) and J[subbb] = 0.09(2) cm[sup-1]) that failed to function as a single molecule magnet due to the presence of low-lying excited states with smaller spin values and a weak magnetic anisotropy. The electron paramagnetic resonance spectrum of 1 in the frozen solution (12 K) displays two signals in the g = 2 and g = 4 regions, each split into six lines due to [sup55]Mn (/= 5/2) superhyperfine couplings. The use of bulky pivalate as a replacement for benzoate provides enough steric bulk to generate a mononuclear species [Mn(L)((CH[sub3])[sub3]CCOO)(CH[sub3]OH)] ∙ CH[sub3]OH (3). The lone manganese(lll) center in this compound has an octahedral geometry, completed by the tetradentate ligand L[sup2-] together with an axially coordinated methanol molecule and a monodentate pivalate. The latter two are connected by a hydrogen bond, thus stabilizing the monodentate carboxylate moiety. Redox behaviors (CV) of 1 and 3 are grossly similar, each undergoing a quasi-reversible reduction process at E[sub1/2] = -0.03 and -0.11 V, respectively, versus a Ag/AgCI reference. [ABSTRACT FROM AUTHOR]

A general protocol for the synthesis of μ-oxo divanadium(V) compounds [LOV(μ-O)VO(Salen)] (1-5) incorporating coordination asymmetry has been developed for the first time. One of the vanadium centers in these compounds has an octahedral environment, completed by tetradentate Salen ligand, while the remaining center has square pyramidal geometry, made up of tridentate biprotic Schiff-base ligands (L2-) with ONO (1-3) and ONS (4, 5) type donor combinations. Single crystal X-ray diffraction analysis, ESI-MS, and NMR (both ¹H and 51V) spectroscopy have been used extensively to establish their identities. The V(1)-O(6)-V(2) bridge angle in these compounds, save 3, lie in a narrow range (166.20(9)-157.79(16)°) with the V2O3 core having a rare type of twist-angular structure, somewhat intermediate between the regular ant!linear and the syn-angular modes. For 3, however, the bridge angle is sufficiently smaller 117.92(8)° that it forces the V2O3 core to adopt an anti-angular geometry. The V(1)⋯V(2) separations in these molecules (3.7921(7)-3.3084(6) Å) are by far the largest compared to their peers containing a V2O3 core. The molecules retain the binuclear structures also in solution as confirmed by NMR spectroscopy. Their redox behaviors appear quite interesting, each undergoing a one-electron reduction in the positive potential range (E1/2, 0.42-0.45 V vs Ag/AgCI) to generate a trapped-valence mixed-oxidation products [LVVO-(μ-O)-OVIVsalen)]1-, confirmed by combined coulometry-EPR experiments. The bent V-O-V bridge in these molecules probably prevents the symmetry-constrained vanadium dxy orbitals, containing the unpaired electron, to overlap effectively via the pπ orbitals of the bridging oxygen atom, thus accounting for the trapped-valence situation in this case. [ABSTRACT FROM AUTHOR]

Dinuclear oxovanadium(V) compounds [LVVO(μ-OH)OVVL](PF6) [H2L = N,N′-tert-ethylene bis(salicylideneimine) (H2Salen) and its derivatives] (1-3) have been obtained by aerial oxidation of VIVOL precursors in THF in the presence of added NH4PF6. The oxidized vanadium(V) probably extracts an OH- ligand from the residual moisture in the solvent and is retained as an unsupported hydroxo-bridge between the metal centers of these compounds as confirmed by single-crystal X-ray diffraction analyses. The molecules of 1-3 have centrosymmetric structures with each vanadium center having a distorted octahedral geometry. The bridging OH- group is located trans to the terminal VOt bond. The latter exerts strong trans labilizing influence to set the participating vanadium centers apart by about 4.1 Å. These separations are by far the largest (e.g., V ⋯ V#, 4.131 Å in 1) among all binuclear compounds containing an unsupported hydroxo bridge reported to date. The complexes retain their identity also in solution as established by ¹H NMR spectroscopy. Electrochemically, the behaviors of 1-3 are quite interesting as studied by cyclic voltammetry in acetonitrile, each undergoing three (except 3) nearly reversible metal-based reductions, all in the positive potential range (e.g., at E1/2 = 0.57, 0.39, and 0.04 V versus Ag/AgCl reference for 1) as indicated by steady state voltammetry. The electrode process at 0.39 V appears to involve a single-step two-electron transfer as revealed from the normal and differential pulse voltammetric data and probably includes a combination of VV-VIV ↔ VIII-VIV mixed oxidation states. Compounds 1-3 thus provide a unique example of divanadium compounds in which the metal centers are linked by an unsupported hydroxo-bridge. [ABSTRACT FROM AUTHOR]

Heterobinuclear copper(II)-zinc(II) complexes and their homobinuclear dicopper(II) counterparts (1-4) of two asymmetric ligands (H2L¹ and H2L²), based on 2-aminocyclopent-1-ene-1-dithiocarboxylate, are reported. The ligands are capable of providing both donor set and coordination number asymmetry in tandem. Metal centers in these complexes are connected by a µ-alkoxo and a bridging pyrazolate moiety, as confirmed by X-ray structure analyses of 1, 3, and 4. The Cu(1) site in the dicopper complex (1) is square planar and so are the copper sites in the Cu-Zn complexes 3 and 4. The pentacoordinated Zn sites in the latter complexes have distorted TBP geometry (τ = 0.74), while the corresponding Cu site in 1 has a highly distorted square pyramidal structure (τ = 0.54). The Cu···Zn separations in 3 and 4 are 3.3782 and 3.3403 Å, respectively, while the Cu···Cu distance in 1 is 3.3687 Å. The dicopper complexes are EPR silent at 77 K, in which the copper(II) centers are coupled by strong antiferromagnetic coupling (J = ca. -290 cm-1) as confirmed by variable-temperature (4-300 K) magnetic measurements. These compounds (1 and 2) undergo two one-electron reductions and a single step two-electron oxidation at ca. -0.26, -1.40, and 1.0 V vs Ag/AgCl reference, respectively, as indicated by cyclic and differential pulse voltammetry done at subambient temperatures. EPR spectra of 3 and 4 display axial anisotropy at 77 K with the g⊥ region being split into multiple lines due to N-superhyperfine coupling (AN = 15.3 × 10-4 cm-4). The observed trend in the spin-Hamiltonian parameters, g¦¦ > g⊥ > 2.04 and ¦A⊥¦ « ¦A¦¦¦ ≈ (120-150) × 10-4 cm-1, indicates a dx²-y²-based ground state with tetragonal site symmetry for the Cu(II) center in these molecules. [ABSTRACT FROM AUTHOR]

Studies the electronic and molecular structures of nickel(II) complexes of three heterodonor ligands. Crystallography; Electrochemical behavior of the binuclear complexes; Electronic spectral features of the compounds.

The metabolically versatile Rhodococcus sp. strain DK17 utilizes indan as a growth substrate via the o-xylene pathway. Metabolite and reverse transcription-PCR analyses indicate that o-xylene dioxygenase hydroxylates indan at the 4,5 position of the aromatic moiety to form cis-indan-4,5-dihydrodiol, which is dehydrogenated to 4,5-indandiol by a dehydrogenase. 4,5-Indandiol undergoes ring cleavage by a meta-cleavage dioxygenase. [ABSTRACT FROM AUTHOR]

In basic media, the coordinated semiquinone radical in the spin-coupled [(bipy)CIVIVO(TCSQ)] 1 (HTCSQ = tetrachlorosemiquinone) undergoes nucleophilic ipso substitution (OH- for Cl-) to generate the chloranilate anion (CA2-) that bridges the vanadium(IV) centers, forming a binuclear compound [(bipy)CIVIVO(CA)OVIVCl(bipy)] 2. [ABSTRACT FROM AUTHOR]

Isovalent μ-oxo divanadium(V) compounds [L¹VO(μ-O)VO(salen)] (1) and its bromo derivative [L²VO(μ-O)VO(salen)]·CH3CN (2) (both H2L¹ and H2L² are tridentate dithiocarbazate-based ONS ligands) with ligands providing donor set and coordination number asymmetry in tandem have been synthesized for the first time; confirmations in favor of these unsymmetrical molecular structures have come from single-crystal X-ray diffraction analysis, as well as from NMR (both ¹H and 51V) spectroscopy. [ABSTRACT FROM AUTHOR]