gebhart/patrepeval huggingface dataset:
Stereospecific deconjugation of alkyl (E)- and (Z)-3-trimethylstannyl-2-alkenoates (1990)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStereospecific deconjugation of alkyl (E)- and (Z)-3-trimethylstannyl-2-alkenoatesEdward Piers and Ashvinikumar V. GavaiCite this: J. Org. Chem. 1990, 55, 8, 2374–2379Publication Date (Print):April 1, 1990Publication History Published online1 May 2002Published inissue 1 April 1990https://pubs.acs.org/doi/10.1021/jo00295a027https://doi.org/10.1021/jo00295a027research-articleACS PublicationsRequest reuse permissionsArticle Views361Altmetric-Citations28LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts
Screening of Inhibitors Using Enzymes Entrapped in Sol−Gel-Derived Materials (2003)

In recent years, a number of new methods have been reported that make use of immobilized enzymes either on microarrays or in bioaffinity columns for high-throughput screening of compound libraries. A key question that arises in such methods is whether immobilization may alter the intrinsic catalytic and inhibition constants of the enzyme. Herein, we examine how immobilization within sol-gel-derived materials affects the catalytic constant (kcat), Michaelis constant (KM), and inhibition constant (KI) of the clinically relevant enzymes Factor Xa, dihydrofolate reductase, cyclooxygenase-2, and gamma-glutamyl transpeptidase. These enzymes were encapsulated into sol-gel-derived glasses produced from either tetraethyl orthosilicate (TEOS) or the newly developed silica precursor diglyceryl silane (DGS). It was found that the catalytic efficiency and long-term stability of all enzymes were improved upon entrapment into DGS-derived materials relative to entrapment in TEOS-based glasses, likely owing to the liberation of the biocompatible reagent glycerol from DGS. The KM values of enzymes entrapped in DGS-derived materials were typically higher than those in solution, whereas upon entrapment, kcat values were generally lowered by a factor of 1.5-7 relative to the value in solution, indicating that substrate turnover was limited by partitioning effects or diffusion through the silica matrix. Nonetheless, the apparent KI value for the entrapped enzyme was in most cases within error of the value in solution, and even in the worst case, the values differed by no more than a factor of 3. The implications of these findings for high-throughput screening are discussed.
Hydrotalcite-supported gold-nanoparticle-catalyzed highly efficient base-free aqueous oxidation of 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid under atmospheric oxygen pressure (2011)

Green synthesis of 2,5-furandicarboxylic acid, one of the most important chemical building blocks from biomass, viaoxidation of 5-hydroxymethylfurfural has been demonstrated using hydrotalcite-supported gold nanoparticle catalyst in water at 368 K under atmospheric oxygen pressure without addition of homogeneous base.
Intracellular pH changes produced by glutamate uptake in rat hippocampal slices (1994)

1. The mean intracellular pH in area CA1 of rat hippocampal slices was monitored fluorescently after loading the cells with the dye BCECF-AM. 2. Including L-glutamate in the solution superfusing the slice led to the intracellular pH becoming more acid. This acidification had a roughly Michaelis-Menten dependence on the superfused glutamate concentration with a half-maximal dose around 200 microM: this value must overestimate the glutamate concentration at most of the cells, which will be reduced by uptake. 3. The glutamate-evoked acidification was not significantly reduced by blockers of glutamate-gated ion channels [6-cyano-7-nitroquinoxaline-2,3- dione (CNQX) and D-aminophosphonovalerate (APV)] nor by blockers of gamma-aminobutyric acid (GABA)- and glycine-gated channels (picrotoxin and strychnine), and so was not produced by H+ entry through alpha-amino-3-hydroxy-5-methyl-4- isoxazolepropionic acid (AMPA) or N-methyl-D-aspartate (NMDA) receptor channels nor by HCO3- exit through the chloride channels controlled by GABA or glycine. 4. The glutamate-evoked acidification was not reduced by tetrodotoxin (TTX), ruling out the possibility of it being generated by action potentials. It was also unaffected by saturation of presynaptic L-amino-4-phosphonobutanoate (AP4) receptors with AP4. 5. In the presence of blockers of glutamate-, GABA-, and glycine-gated channels, the acidification showed the pharmacology of glutamate uptake and was reduced by a glutamate uptake blocker. 6. The glutamate-evoked acidification showed an ion dependence similar to that of glutamate uptake. It was abolished by removal of extracellular sodium and was reduced by raising the extracellular potassium concentration. It was unaffected by blockers of Na+/H+ exchange (amiloride) and Na+/HCO3- cotransport [4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS)] and so was not produced by the Na+ influx accompanying glutamate uptake changing the activity of these carriers. 7. These data show that the glutamate uptake carrier acidifies hippocampal cells, possibly because it transports a pH-changing anion out of the cell as in salamander glial cells. Glutamate uptake may thus contribute to activity-induced pH changes in the nervous system.
Boron neutron capture therapy of cancer. (1990)

The theoretical advantage of BCNT is that it is a two component or binary system, consisting of 10 B and thermal neutrons, which when combined together generate high LET radiation capable of selectively destroying tumor cells without significant damage to normal tissues. In order for BCNT to succeed a critical amount of 10 B and a sufficient number of thermal neutrons must be delivered to individual tumor cells
Susceptibility loci for complex regional pain syndrome (2003)

An association between HLA-DR13 and patients with complex regional pain syndrome (CRPS) who progressed towards multifocal or generalized tonic dystonia was recently reported. We now report on a new locus, centromeric in HLA-class I, which was significantly associated with a spontaneous development of CRPS, suggesting an interaction between trauma severity and genetic factors conferring CRPS susceptibility. Additionally, an association with the D6S1014 locus was found, supporting the previous finding of an association with HLA-DR13.
A General Strategy for the Synthesis of Vincamajine-Related Indole Alkaloids:  Stereocontrolled Total Synthesis of (+)-Dehydrovoachalotine, (−)-Vincamajinine, and (−)-11-Methoxy-17-epivincamajine as Well as the Related Quebrachidine Diol, Vincamajine Diol, and Vincarinol1 (2005)

[structures: see text] The highly convergent stereocontrolled total synthesis of (-)-vincamajinine (7), (-)-11-methoxy-17-epivincamajine (9), and the oxygen-bridged (+)-dehydrovoachalotine (22) are described. Key steps in the synthesis of 7 and 9 involved the stereospecific enolate-driven palladium-catalyzed cross-coupling reaction, a Tollens reaction, an acid-assisted intramolecular cyclization to form the C(7)-C(17) quaternary center, and two stereospecific reductions. The efficiency of this strategy is illustrated by the completion of the synthesis of 7 and 9 in 16 [from d-(+)-tryptophan methyl ester 17] and 17 (from the Schöllkopf chiral auxiliary 27) reaction vessels, respectively. This constitutes the first total synthesis of these indole alkaloids and provides the first regiospecific route to 11-methoxy-substituted ajmaline/vincamajine-related alkaloids. The synthesis of 22 required a novel DDQ-mediated cyclization to furnish the C(6)-O(17) bond, executed in stereospecific fashion. Completion of these syntheses illustrates a concise and versatile strategy for the synthesis of vincamajine-related alkaloids, which has also been employed to prepare the related compounds quebrachidine diol (53), vincamajine diol (56), and vincarinol (59).
Modeling of Oxygen-Inhibited Free Radical Photopolymerization in a PDMS Microfluidic Device (2008)

Free-radical photopolymerization performed within PDMS microfluidic devices is now used for a variety of applications. We propose, through model and experiment, that atmospheric oxygen diffusing in through the porous PDMS is responsible for the presence, under UV light, of a thin, un-cross-linked film of oligomer abutting the walls of an all-PDMS device. After the advent of light exposure, an induction time τi is required before the oxygen present in the oligomer is depleted, and cross-linking reactions can begin. A polymerized structure then grows from the center of the device outward, increasing sharply in height with time and leaving only a thin un-cross-linked film of thickness, δi,c, close to the walls where oxygen can penetrate. Under suitable simplification of the reaction−diffusion model developed, scaling relationships were obtained for τi (∼Da−1) and δi,c (∼Da−1/2) as a function of a Damköhler number, Da. The relationships were successfully verified by comparison with both the full solution and experimental data. The analysis shows that control over particle height can be obtained more easily by changing initiator concentration, irradiation intensity, or channel height rather than exposure time.
Protein Adsorption on Biomaterial and Nanomaterial Surfaces: A Molecular Modeling Approach to Study Non-Covalent Interactions (2010)

Atomistic computer simulations of protein adsorption on the heterogeneous surface of biomaterials and nanomaterials are reviewed. First, we present a very brief introduction to some relevant issues concerning force fields and the computational methodologies currently used, in particular molecular dynamics simulations for studying non-covalent interactions in general. The main results are then discussed, considering the adsorption of different protein subdomains and of whole proteins on different surfaces of an unlike nature. In particular, we review our results for lysozyme and some protein subdomains with a different secondary structure on a strongly hydrophobic graphite surface and on a highly hydrophilic polymeric surface, and preliminary results of protein adsorption on single-walled carbon nanotubes, focusing on the effect of the surface topography and curvature. We also discuss the results obtained in other groups for other proteins or protein subdomains being adsorbed on ceramic materials, either purely ionic (MgO, hydroxyapatite) or covalent (SiO₂, taken as a model for mica), and on self-assembled monolayers terminated with various chemical functionalities. The insights gained from these simulations are commented on critically, in particular the use of an implicit solvent or the use of explicit water and the lack of final equilibrium usually achieved in the latter case. Finally, we present some open issues for computer simulations of protein adsorption at an interface, and provide an outlook about possible future work in this area.
Erratum: “Spectra analysis of annealed Hg1−xCdxTe molecular beam epitaxial films” [Appl. Phys. Lett. 73, 1376 (1998)] (1998)

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Treatment with Low Dose Human Recombinant Interferon-Alpha-2-ARG Induces Complete Remission in Patients with Hairy Cell Leukemia (1985)

Five cases with advanced hairy cell leukemia refractory to treatment with splenectomy and chemotherapy as well as one patient presenting with a stage-A response to splenectomy were treated with rhu-IFN-α2-arg. 5 × 106 were administered intramuscularly every day. Both patients, with advanced disease resistant to conventional therapy and treated for six or more months with rhu-IFN-α2-arg, achieved complete clinical remissions. Three further cases treated for less than half a year and also with advanced disease achieved partial remission states with marked reduction of circulating hairy cells and with recovery of normal hemopoiesis. Minimal residual disease in the remaining patient during a three-month period of treatment did not respond. Side effects of rhu-IFN-α2 low dose therapy were minimal in 5 cases and comprised a severe leukopenia reversible after dose reduction in one patient.
Most mammalian mRNAs are conserved targets of microRNAs (2008)

MicroRNAs (miRNAs) are small endogenous RNAs that pair to sites in mRNAs to direct post-transcriptional repression. Many sites that match the miRNA seed (nucleotides 2-7), particularly those in 3' untranslated regions (3'UTRs), are preferentially conserved. Here, we overhauled our tool for finding preferential conservation of sequence motifs and applied it to the analysis of human 3'UTRs, increasing by nearly threefold the detected number of preferentially conserved miRNA target sites. The new tool more efficiently incorporates new genomes and more completely controls for background conservation by accounting for mutational biases, dinucleotide conservation rates, and the conservation rates of individual UTRs. The improved background model enabled preferential conservation of a new site type, the "offset 6mer," to be detected. In total, >45,000 miRNA target sites within human 3'UTRs are conserved above background levels, and >60% of human protein-coding genes have been under selective pressure to maintain pairing to miRNAs. Mammalian-specific miRNAs have far fewer conserved targets than do the more broadly conserved miRNAs, even when considering only more recently emerged targets. Although pairing to the 3' end of miRNAs can compensate for seed mismatches, this class of sites constitutes less than 2% of all preferentially conserved sites detected. The new tool enables statistically powerful analysis of individual miRNA target sites, with the probability of preferentially conserved targeting (P(CT)) correlating with experimental measurements of repression. Our expanded set of target predictions (including conserved 3'-compensatory sites), are available at the TargetScan website, which displays the P(CT) for each site and each predicted target.
Detection of 9-Tetrahydrocannabinol in Exhaled Breath Collected from Cannabis Users (2011)

Exhaled breath has recently been proposed as a new possible matrix for drugs of abuse testing. A key drug is cannabis, and the present study was aimed at investigating the possibility of detecting tetrahydrocannabinol and tetrahydrocannabinol carboxylic acid in exhaled breath after cannabis smoking. Exhaled breath was sampled from 10 regular cannabis users and 8 controls by directing the exhaled breath by suction through an Empore C(18) disk. The disk was extracted with hexane/ethyl acetate, and the resulting extract was evaporated to dryness and redissolved in 100 μL hexane/ethyl acetate. A 3-μL aliquot was injected onto the LC-MS-MS system and analyzed using positive electrospray ionization and selected reaction monitoring. In samples collected 1-12 h after cannabis smoking, tetrahydrocannabinol was detected in all 10 subjects. The rate of excretion was between 9.0 and 77.3 pg/min. Identification of tetrahydrocannabinol was based on correct retention time relative to tetrahydrocannabinol-d(3) and correct product ion ratio. In three samples, peaks were observed for tetrahydrocannabinol carboxylic acid, but these did not fulfill identification criteria. Neither tetrahydrocannabinol or tetrahydrocannabinol carboxylic acid was detected in the controls. These results confirm older reports that tetrahydrocannabinol is present in exhaled breath following cannabis smoking and extend the detection time from minutes to hours. The results further support the idea that exhaled breath is a promising matrix for drugs-of-abuse testing.
Patterned polymer matrix promotes stemness and cell-cell interaction of adult stem cells (2015)

This approach meets the need for scalable, highly repeatable, and tuneable models that mimic extracellular matrix features that signal for maintenance of hMSC stemness.
PU.1 as an essential activator for the expression of gp91phoxgene in human peripheral neutrophils, monocytes, and B lymphocytes (1998)

We have reported a deficiency of a 91-kDa glycoprotein component of the phagocyte NADPH oxidase (gp91(phox)) in neutrophils, monocytes, and B lymphocytes of a patient with X chromosome-linked chronic granulomatous disease. Sequence analysis of his gp91(phox) gene revealed a single-base mutation (C --> T) at position -53. Electrophoresis mobility-shift assays showed that both PU.1 and hematopoietic-associated factor 1 (HAF-1) bound to the inverted PU.1 consensus sequence centered at position -53 of the gp91(phox) promoter, and the mutation at position -53 strongly inhibited the binding of both factors. It was also indicated that a mutation at position -50 strongly inhibited PU.1 binding but hardly inhibited HAF-1 binding, and a mutation at position -56 had an opposite binding specificity for these factors. In transient expression assay using HEL cells, which express PU.1 and HAF-1, the mutations at positions -53 and -50 significantly reduced the gp91(phox) promoter activity; however, the mutation at position -56 did not affect the promoter activity. In transient cotransfection study, PU.1 dramatically activated the gp91(phox) promoter in Jurkat T cells, which originally contained HAF-1 but not PU.1. In addition, the single-base mutation (C --> T) at position -52 that was identified in a patient with chronic granulomatous disease inhibited the binding of PU.1 to the promoter. We therefore conclude that PU.1 is an essential activator for the expression of gp91(phox) gene in human neutrophils, monocytes, and B lymphocytes.
A Targetable Fluorescent Probe for Imaging Hydrogen Peroxide in the Mitochondria of Living Cells (2008)

We present the design, synthesis, and biological applications of mitochondria peroxy yellow 1 (MitoPY1), a new type of bifunctional fluorescent probe for imaging hydrogen peroxide levels within the mitochondria of living cells. MitoPY1 combines a chemoselective boronate-based switch and a mitochondrial-targeting phosphonium moiety for detection of hydrogen peroxide localized to cellular mitochondria. Confocal microscopy and flow cytometry experiments in a variety of mammalian cell types show that MitoPY1 can visualize localized changes in mitochondrial hydrogen peroxide concentrations generated by situations of oxidative stress.
Galectin-3 in Heart Failure—Linking Fibrosis, Remodeling, and Progression (2010)

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Fractionated Plasma Separation and Adsorption System: A Novel System for Blood Purification to Remove Albumin Bound Substances (1999)

The removal of albumin bound substances has gained increasing interest in different diseases, especially in acute and chronic liver disease. Therefore, a new system, the fractionated plasma separation and adsorption (FPSA) system, was developed based on combined membrane and adsorbent blood purification techniques. The most important contribution to the FPSA system was the development of a new polysulfone hollow-fiber filter, which is characterized by a sieving coefficient of 0.89 for human serum albumin (HSA) but only of 0.17 for fibrinogen, and 0 (zero) for IgM immunoglobulins. Using a closed filtrate circuit connected to the new polysulfone filter which integrates 1 or 2 adsorption columns and also a high flux dialyzer adapted to a dialysis machine, the FPSA system opens excellent possibilities for the relatively specific removal of albumin bound substances from the blood such as albumin bound bilirubin or even tryptophan. In comparison to other systems (for example, the Molecular Adsorbent Recirculating System [MARS] and albumin dialysis systems), the FPSA system enables much higher elimination of strongly bound albumin substances. The first clinical investigations have recently started based on a modified dialysis machine designed with all necessary safety measures.
The Longevity Annuity: An Annuity for Everyone? (2008)

As of 2005, U.S. individuals had an estimated $7.4 trillion invested in IRAs and employer-sponsored retirement accounts. Many retirees will thus face the difficult problem of turning a pool of assets into a stream of retirement income. Purchasing an immediate annuity is a common recommendation for retirees trying to maximize retirement spending. The vast majority of retirees, however, are unwilling to annuitize all their assets. This research demonstrates that a “longevity annuity,” which is distinct from an immediate annuity in that payouts begin late in retirement, is optimal for retirees unwilling to fully annuitize. For a typical retiree, allocating 10–15 percent of wealth to a longevity annuity creates spending benefits comparable to an allocation to an immediate annuity of 60 percent or more.
A Rare Genetically Determined Variant of Pseudocholinesterase in two German Families with High Plasma Enzyme Activity (1979)

Activity of pseudocholinesterase (acylcholine-acyl-hydrolase) elevated up to four times has been detected in sera of members of two German families. The catalytic concentrations of the pseudocholinesterase of the afflicted members of both families (male and female) varied between 4800 U/l and 10 200 U/o (acetylthiocholine iodide substrate). The pseudocholinesterase of the propositi exhibits isoenzyme separation patterns in polyacrylamide electrophoresis as well as in electrofocussing which are different from those of pseudocholinesterase from normal persons. No differences could be seen as regards the Km of substrates or the inhibition by dibucaine, fluoride or succinyldiocholine.
Structure Based Substrate Specificity Analysis of Heparan Sulfate 6-O-Sulfotransferases (2016)

Heparan sulfate (HS) is a sulfated polysaccharide exhibiting essential physiological functions. HS 6-O-sulfotransferase (6-OST) transfers a sulfo group to the 6-OH position of glucosamine units to confer a variety of HS biological activities. There are three different isoforms of 6-OST in the human genome. Here, we report crystal structures of the ternary complex of 6-OST with the sulfo donor analog 3'-phosphoadenosine 5'-phosphate and three different oligosaccharide substrates at 1.95 to 2.1 Å resolutions. Structural and mutational analyses reveal amino acid residues that contribute to catalysis and substrate recognition of 6-OST. Unexpectedly, the structures reveal 6-OST engages HS in a completely different orientation than other HS sulfotransferases and sheds light on the basic HS requirements for specificity. These findings also contribute structural information to understand mutations in human 6-OST isoform 1 associated with the human genetic disease idiopathic hypogonadotropic hypogonadism characterized by incomplete or lack of puberty.