350 research outputs found

    A new bifunctional catalyst for tandem Heck-asymmetric dihydroxylation of olefins

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    A new bifunctional catalyst consisting of active palladium and osmium species anchored on silica gel through a mercaptopropyl spacer and a cinchona alkaloid respectively has been prepared for the first time and used in the heterogeneous tandem Heck-asymmetric dihydroxylation of olefins to afford diols with excellent yields and enantiomeric excesses (ee's) in presence of N-methylmorpholine Noxide or K3Fe(CN)6 as cooxidants

    A clinico-pathological study of pigmented cutaneous lesions: a one-year prospective study in a tertiary care hospital

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    Background: Pigmented lesions are group of lesions which have melanocytic proliferation with very common clinical presentation. Diagnosing these pigmented lesions and differentiating cutaneous melanocytic lesions from non-melanocytic lesions poses a great challenge for the pathologist.Methods: A Prospective study was conducted for one year from June 2016 to June 2017 sent to the Department of Pathology, Andhra Medical College, Visakhapatnam, a tertiary care centre in southern India consisting of 44 pigmented lesions. Specimens were formalin fixed and the tissue was adequately processed for histopathological examination. The sections were stained routinely with hematoxylin and eosin stain and examined under light microscopy.Results: Out of 44 cases, 24 cases were cutaneous melanocytic lesions which include benign naevi 22 (50%) and 2 (4.6%) malignant melanoma cases. The other 20 cases were cutaneous non melanocytic lesions which include 5 (11.4%) pigmented seborrheic keratosis, 6 (13.7%) pigmented basal cell carcinoma, 1 (2.3%) pigmented actinic keratosis and 8 (18%) cases of naevus sebaceous. Most common effected age group was <21 years (31.81%), male: female ratio is 1:2 and most common site involved was face 29 cases (65.9%). Most common pigmented lesions were benign melanocytic nevi 22 (50%) followed by naevus sebaceous 8 (18%) cases. 32 (72.71%) cases were consistent with both clinico-histopathological correlation.Conclusions: Benign melanocytic nevi are most common lesions obtained, seborric keratosis and pigmented basal cell carcinoma were most common mimickers of melanocytic lesions, hence a careful histopathological diagnosis is important

    Electron paramagnetic resonance of Cu<SUP>2+</SUP> ion in CsCl single crystals

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    Electron paramagnetic resonance spectrum of the Cu2+ ion in CsCl is studied at different temperatures. The local symmetry at the Cu2+ site is found to be tetragonal. A model of substitutional Cu2+ ion associated with a first neighbour cation vacancy is proposed to explain the observed spectrum

    Properties of iron-modified-by-silver supported on mordenite as catalysts for nox reduction

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    A series of mono and bimetallic catalysts based on a Fe-Ag mixture deposited on mordenite was prepared by ion-exchange and evaluated in the catalytic activity test of the de-NOx reaction in the presence of CO/C3H6. The activity results showed that the most active samples were the Fe-containing ones, and at high temperatures, a co-promoter effect of Ag on the activity of Fe catalysts was also observed. The influence of the order of cation deposition on catalysts formation and their physicochemical properties was studied by FTIR (Fourier Transform Infrared Spectroscopy) of adsorbed NO, XANES (X-ray Absorption Near-Edge Structure), and EXAFS (Extended X-ray Absorption Fine Structure) and discussed in terms of the state of iron. Results of Fe K-edge XANES oscillations showed that, in FeMOR catalysts, iron was present in a disordered state as Fe3+ and Fe2+. In FeAgMOR, the prevailing species was Fe3+, while in the AgFeMOR catalyst, the state of iron was intermediate or mixed between FeMOR and FeAgMOR. The Fe K-edge EXAFS results were characteristic of a disordered phase, the first coordination sphere being asymmetric with two different Fe-O distances. In FeAgMOR and AgFeMOR, coordination of Fe-O was similar to Fe2O3 with a few amount of Fe2+ species. We may conclude that, in the bimetallic FeAgMOR and AgFeMOR samples, a certain amount of tetrahedral Al3+ ions in the mordenite framework is replaced by Fe3+ ions, confirming the previous reports that these species are active sites for the de-NOx reaction. Based on the thermodynamic analysis and experimental data, also, it was confirmed that the order of deposition of the components influenced the mechanism of active sites&rsquo; formation during the two steps ion-exchange synthesis

    Electrochemical and lithium-ion transport properties of layered Li-rich Li1.10(Ni0.32X0.01Co0.33Mn0.33)O2(X = Dy/Gd/Ho) positive electrodes

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    Layer structured Li1.10(Ni0.32X0.01Co0.33Mn0.33)O2 (X = Dy/Gd/Ho) compounds were synthesized via the microwave assisted solvothermal route. The impacts of doping on the electrical and electrochemical properties of Li1.10 (Ni0.32X0.01Co0.33Mn0.33)O2 compounds were investigated. Rietveld refined XRD pattern showed Li1.10 (Ni0.32X0.01Co0.33Mn0.33)O2 compounds with layered hexagonal structure. SEM images revealed the compounds with micrometer sized grains. The Li1.10 (Ni0.33Co0.33Mn0.33)O2 compound delivered an initial discharge capacity of 197 mAh/g at 0.2C and retained a capacity of 163mAh/g after 50th cycle in the voltage window of 2.5-4.6V. The cycling stability of Li1.10(Ni0.33Co0.33Mn0.33)O2 compound was improved with rare earth doping. Li1.10(Ni0.32Dy0.01Co0.33Mn0.33)O2 compound delivered the discharge capacity of 166 mAh/g after50th cycle in the potential window 2.5-4.6V at 0.2C with 100% capacity retention. AC impedance studies displayed the electrical conductivity in the order of 10-6 S/cm. Wagner polarization analysis revealed the improvement in electronic transference number via rare earth doping

    Electrochemical and lithium-ion transport properties of layered Li-rich Li1.10(Ni0.32X0.01Co0.33Mn0.33)O2 (X = Dy/Gd/Ho) positive electrodes

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    864-876Layer structured Li1.10(Ni0.32X0.01Co0.33Mn0.33)O2 (X = Dy/Gd/Ho) compounds were synthesized via the microwave assisted solvothermal route. The impacts of doping on the electrical and electrochemical properties of Li1.10 (Ni0.32X0.01Co0.33Mn0.33)O2 compounds were investigated. Rietveld refined XRD pattern showed Li1.10 (Ni0.32X0.01Co0.33Mn0.33)O2 compounds with layered hexagonal structure. SEM images revealed the compounds with micrometer sized grains. The Li1.10 (Ni0.33Co0.33Mn0.33)O2 compound delivered an initial discharge capacity of 197 mAh/g at 0.2C and retained a capacity of 163mAh/g after 50th cycle in the voltage window of 2.5-4.6V. The cycling stability of Li1.10(Ni0.33Co0.33Mn0.33)O2 compound was improved with rare earth doping. Li1.10(Ni0.32Dy0.01Co0.33Mn0.33)O2 compound delivered the discharge capacity of 166 mAh/g after50th cycle in the potential window 2.5-4.6V at 0.2C with 100% capacity retention. AC impedance studies displayed the electrical conductivity in the order of 10-6 S/cm. Wagner polarization analysis revealed the improvement in electronic transference number via rare earth doping

    Apoptotic Engulfment Pathway and Schizophrenia

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    Background: Apoptosis has been speculated to be involved in schizophrenia. In a previously study, we reported the association of the MEGF10 gene with the disease. In this study, we followed the apoptotic engulfment pathway involving the MEGF10, GULP1, ABCA1 and ABCA7 genes and tested their association with the disease. Methodology/Principal Findings: Ten, eleven and five SNPs were genotyped in the GULP1, ABCA1 and ABCA7 genes respectively for the ISHDSF and ICCSS samples. In all 3 genes, we observed nominally significant associations. Rs2004888 at GULP1 was significant in both ISHDSF and ICCSS samples (p = 0.0083 and 0.0437 respectively). We sought replication in independent samples for this marker and found highly significant association (p = 0.0003) in 3 Caucasian replication samples. But it was not significant in the 2 Chinese replication samples. In addition, we found a significant 2-marker (rs2242436 * rs3858075) interaction between the ABCA1 and ABCA7 genes in the ISHDSF sample (p = 0.0022) and a 3-marker interaction (rs246896 * rs4522565 * rs3858075) amongst the MEGF10, GULP1 and ABCA1 genes in the ICCSS sample (p = 0.0120). Rs3858075 in the ABCA1 gene was involved in both 2- and 3-marker interactions in the two samples. Conclusions/Significance: From these data, we concluded that the GULP1 gene and the apoptotic engulfment pathway are involved in schizophrenia in subjects of European ancestry and multiple genes in the pathway may interactively increase the risks to the disease. © 2009 Chen et al

    MEKK1-MKK4-JNK-AP1 Pathway Negatively Regulates Rgs4 Expression in Colonic Smooth Muscle Cells

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    Background: Regulator of G-protein Signaling 4 (RGS4) plays an important role in regulating smooth muscle contraction, cardiac development, neural plasticity and psychiatric disorder. However, the underlying regulatory mechanisms remain elusive. Our recent studies have shown that upregulation of Rgs4 by interleukin (IL)-1b is mediated by the activation of NFkB signaling and modulated by extracellular signal-regulated kinases, p38 mitogen-activated protein kinase, and phosphoinositide-3 kinase. Here we investigate the effect of the c-Jun N-terminal kinase (JNK) pathway on Rgs4 expression in rabbit colonic smooth muscle cells. Methodology/Principal Findings: Cultured cells at first passage were treated with or without IL-1b (10 ng/ml) in the presence or absence of the selective JNK inhibitor (SP600125) or JNK small hairpin RNA (shRNA). The expression levels of Rgs4 mRNA and protein were determined by real-time RT-PCR and Western blot respectively. SP600125 or JNK shRNA increased Rgs4 expression in the absence or presence of IL-1b stimulation. Overexpression of MEKK1, the key upstream kinase of JNK, inhibited Rgs4 expression, which was reversed by co-expression of JNK shRNA or dominant-negative mutants for MKK4 or JNK. Both constitutive and inducible upregulation of Rgs4 expression by SP600125 was significantly inhibited by pretreatment with the transcription inhibitor, actinomycin D. Dual reporter assay showed that pretreatment with SP600125 sensitized the promoter activity of Rgs4 in response to IL-1b. Mutation of the AP1-binding site within Rgs

    Genome-Wide Association Study of Treatment Refractory Schizophrenia in Han Chinese

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    We report the first genome-wide association study of a joint analysis using 795 Han Chinese individuals with treatment-refractory schizophrenia (TRS) and 806 controls. Three loci showed suggestive significant association with TRS were identified. These loci include: rs10218843 (P = 3.04×10−7) and rs11265461 (P = 1.94×10−7) are adjacent to signaling lymphocytic activation molecule family member 1 (SLAMF1); rs4699030 (P = 1.94×10−6) and rs230529 (P = 1.74×10−7) are located in the gene nuclear factor of kappa light polypeptide gene enhancer in B-cells 1 (NFKB1); and rs13049286 (P = 3.05×10−5) and rs3827219 (P = 1.66×10−5) fall in receptor-interacting serine/threonine-protein kinase 4 (RIPK4). One isolated single nucleotide polymorphism (SNP), rs739617 (P = 3.87×10−5) was also identified to be associated with TRS. The -94delATTG allele (rs28362691) located in the promoter region of NFKB1 was identified by resequencing and was found to associate with TRS (P = 4.85×10−6). The promoter assay demonstrated that the -94delATTG allele had a significant lower promoter activity than the -94insATTG allele in the SH-SY5Y cells. This study suggests that rs28362691 in NFKB1 might be involved in the development of TRS

    Positive Selection within the Schizophrenia-Associated GABA(A) Receptor β(2) Gene

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    The gamma-aminobutyric acid type-A (GABA(A)) receptor plays a major role in inhibitory neurotransmissions. Intronic SNPs and haplotypes in GABRB2, the gene for GABA(A) receptor β(2) subunit, are associated with schizophrenia and correlated with the expression of two alternatively spliced β(2) isoforms. In the present study, using chimpanzee as an ancestral reference, high frequencies were observed for the derived (D) alleles of the four SNPs rs6556547, rs187269, rs1816071 and rs1816072 in GABRB2, suggesting the occurrence of positive selection for these derived alleles. Coalescence-based simulation showed that the population frequency spectra and the frequencies of H56, the haplotype having all four D alleles, significantly deviated from neutral-evolution expectation in various demographic models. Haplotypes containing the derived allele of rs1816072 displayed significantly less diversity compared to haplotypes containing its ancestral allele, further supporting positive selection. The variations in DD-genotype frequencies in five human populations provided a snapshot of the evolutionary history, which suggested that the positive selections of the D alleles are recent and likely ongoing. The divergence between the DD-genotype profiles of schizophrenic and control samples pointed to the schizophrenia-relevance of positive selections, with the schizophrenic samples showing weakened selections compared to the controls. These DD-genotypes were previously found to increase the expression of β(2), especially its long isoform. Electrophysiological analysis showed that this long β(2) isoform favored by the positive selections is more sensitive than the short isoform to the inhibition of GABA(A) receptor function by energy depletion. These findings represent the first demonstration of positive selection in a schizophrenia-associated gene
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