gebhart/patrepeval huggingface dataset:
Syntheses, Characterizations, and Redox Behavior of Optically Active Viologens and Bisviologens (1999)

Abstract Optically active viologens, containing [1-(1-naphthyl)-, 1-phenyl-, and 1-cyclohexylethyl]carbamoylmethyl groups, have been synthesized and characterized. The redox behavior of the chiral viologens was studied compared with achiral viologens. The monoviologens containing naphthyl groups show an intermolecular charge-transfer interaction between the bipyridinium and naphthyl groups in aqueous solution. The association constants are dependent on the chirality of the viologens and larger in the (S,S)- and (R,R)-isomers than in the (R,S)-one. Chiral bisviologens, in which two viologen units are linked with a trimethylene chain, have also been synthesized and characterized. Although the intermolecular charge-transfer interaction between the bipyridinium and viologen units of bisviologens was very weak in solution, such an interaction was appreciably observed in a solid state, which was confirmed by X-ray crystallography. Monoradical trications produced by a one-electron reduction of bisviologens disproportionate more easily in the (R,S)-isomers than in the (S,S)- and (R,R)-ones. The disproportionation is controlled by the steric bulk of the chiral substituents in intramolecular association between two viologen radical units of diradical dications.
Current Applications of Polysaccharides in Colon Targeting (1996)

Polysaccharides have over the years been used widely in pharmaceutical, chemical, and biochemical drug delivery. This family of natural polymers has an appeal to the area of drug delivery as it is comprised of polymers with a large number of derivatizable groups, a wide range of molecular weights, varying chemical compositions, and for the most part, a low toxicity and biodegradability, yet a high stability. The main scope of this review is to relate the polysaccharides available now to the rapidly growing field of colonic drug delivery. Polysaccharides have been applied to the area as controlled release coatings, matrices, macromolecular carriers, and biodegradable carriers. Bacterial sources of polysaccharidases as well as a detailed treatise of the enzymatic flora of the colonic region are discussed, followed by a presentation of the polysaccharides available for the purpose of colon-specific drug delivery. A final overview of the various approaches to obtain colon-specific delivery by using polysaccharides and a summary of available in vitro and in vivo testing methods will lead to the conclusion that polysaccharides at this point appear to be very promising compounds for use in obtaining colon-specific drug delivery systems.
Delivery of short hairpin RNAs by transkingdom RNA interference modulates the classical ABCB1-mediated multidrug-resistant phenotype of cancer cells (2009)

Delivery of RNA interference (RNAi)-mediating agents to target cells is one of the major obstacles for the development of RNAi-based therapies. One strategy to overcome this barrier is transkingdom RNAi (tkRNAi). This technology uses non-pathogenic bacteria to produce and deliver therapeutic short hairpin RNA (shRNA) into target cells to induce RNAi. In this study, the tkRNAi approach was used for modulation of the "classical" ABCB1-mediated multidrug resistance (MDR) in human cancer cells. Subsequent to treatment with anti-ABCB1 shRNA expression vector bearing E. coli, MDR cancer cells (EPG85 257RDB) showed 45% less ABCB1 mRNA expression. ABCB1 protein expression levels were reduced to a point at which merely a weak band could be detected. Drug accumulation was enhanced 11-fold, to an extent that it reached 45% of the levels in non-resistant cells and resistance to daunorubicin was decreased by 40%. The data provide the proof-of-concept that tkRNAi is suitable for modulation of "classical" MDR in human cancer cells. Overall, the prototype tkRNAi system tested here did not yet attain the levels of gene silencing seen with conventional siRNAs nor virally delivered shRNAs; but the tkRNAi system for gene-silencing of ABCB1 is still being optimized, and may become a powerful tool for delivery of RNAi effectors for the reversal of cancer MDR in future.
Cardiac Mapping Instrumentation for the Instantaneous Display of Endocardial and Epicardial Activation (1987)

A real-time mapping system is described that allows instant display of both endocardial and epicardial activation as monitored by an array of transmural plunge-needle electrodes in the intact in situ heart. From the total cardiac muscle mass, 768 electrograms are recorded, with a programmable feature allowing the rapid and unrestricted selection of 110 endocardial electrograms for automated analysis. An activation analyzer (consisting of parallel analog circuitry) provides an activation image in real time, while video recorders provide both raw and processed data storage with the capability of immediate slow-motion replay. The nature of the data acquisition (110 plunge needles) limits this system to the experimental arrhythmia laboratory where its chief advantage is the enabling of the multichannel recording of endo data without the complications of open heart surgery. Equally important is the ability to automatically store the endocardial activation image locked in time to the simultaneously recorded epicardial image.
Direct and progressive differentiation of human embryonic stem cells into the chondrogenic lineage (2010)

Treatment of common and debilitating degenerative cartilage diseases particularly osteoarthritis is a clinical challenge because of the limited capacity of the tissue for self-repair. Because of their unlimited capacity for self-renewal and ability to differentiate into multiple lineages, human embryonic stem cells (hESCs) are a potentially powerful tool for repair of cartilage defects. The primary objective of the present study was to develop culture systems and conditions that enable hESCs to directly and uniformly differentiate into the chondrogenic lineage without prior embryoid body (EB) formation, since the inherent cellular heterogeneity of EBs hinders obtaining homogeneous populations of chondrogenic cells that can be used for cartilage repair. To this end, we have subjected undifferentiated pluripotent hESCs to the high density micromass culture conditions we have extensively used to direct the differentiation of embryonic limb bud mesenchymal cells into chondrocytes. We report that micromass cultures of pluripotent hESCs undergo direct, rapid, progressive, and substantially uniform chondrogenic differentiation in the presence of BMP2 or a combination of BMP2 and TGF-beta1, signaling molecules that act in concert to regulate chondrogenesis in the developing limb. The gene expression profiles of hESC-derived cultures harvested at various times during the progression of their differentiation has enabled us to identify cultures comprising cells in different phases of the chondrogenic lineage ranging from cultures just entering the lineage to well differentiated chondrocytes. Thus, we are poised to compare the abilities of hESC-derived progenitors in different phases of the chondrogenic lineage for cartilage repair.
Insecticidal activity of the pyrethrins and related compounds X 5‐benzyl‐3‐furylmethyl 2,2‐dimethyicyclopropanecarboxylates with ethylenic substituents at position 3 on the cyclopropane ring (1976)

Abstract The insecticidal activities against houseflies (Musca domestica L.) and mustard beetles ( Phaedon cochleariae Fab.) of the chrysanthemate bioresmethrin, and of 31 related 5‐benzyl‐3‐furylmethyl 2,2‐dimethylcyclopropanecarboxylates with alkenyl, alkadienyl or alkoxycarbonylalkenyl substituents at position 3 of the cyclopropane ring are compared to determine the relative influence of the isobutenyl sidechain (as in chrysanthemates) and of the other side chains. Several substituents, in particular ( E )‐ or ( Z )‐butadienyl or ‐pentadienyl, give considerably greater activity than isobutenyl but alkoxycarbonyl compounds are less potent.
Synthesis of Early Transition Metal Bisphenolate Complexes and Their Use as Olefin Polymerization Catalysts (2009)

Bisphenolate ligands with pyridine- and benzene-diyl linkers have been synthesized and metalated with group 4 and 5 transition metals. The solid-state structures of some of the group 4 complexes have been solved. The titanium, zirconium, hafnium, and vanadium complexes were tested for propylene polymerization and ethylene/1-octene copolymerization activities with methylaluminoxane as cocatalyst. The vanadium(III) precatalyst is the most active for propylene polymerization and shows the highest 1-octene incorporation for ethylene/1-octene copolymerization. The zirconium(IV) precatalyst was the most active for propylene polymerization of the group 4 precatalysts. Titanium(IV) and zirconium(IV) precatalysts with pyridine-diyl linkers provided mixtures of isotactic and atactic polypropylene while titanium(IV) precatalysts with benzene-diyl linkers gave atactic polypropylene only. The hafnium(IV) precatalyst with a pyridine-diyl linker generated moderately isotactic polypropylene.
Preparation and Polymerization of Unsaturated Quaternary Ammonium Compounds (1949)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPreparation and Polymerization of Unsaturated Quaternary Ammonium CompoundsGeorge B. Butler and Robert L. BunchCite this: J. Am. Chem. Soc. 1949, 71, 9, 3120–3122Publication Date (Print):September 1, 1949Publication History Published online1 May 2002Published inissue 1 September 1949https://pubs.acs.org/doi/10.1021/ja01177a053https://doi.org/10.1021/ja01177a053research-articleACS PublicationsRequest reuse permissionsArticle Views873Altmetric-Citations85LEARN 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-Alertsclose Get e-Alerts
Identification of DNA-cisplatin adducts in a blind trial of insituscanning tunneling microscopy (1993)

Scanning tunneling microscopy (STM) reveals nanometer scale details of hydrated DNA but the interpretation of the images is controversial because of substrate artifacts and the lack of a theory for image contrast. We demonstrate that we have overcome these problems by identifying five DNA samples by their STM images alone in a blinded trial. The samples were single-stranded and double-stranded DNA with and without covalent modification by the anti-tumor drug cisplatin. The cisplatin adducts were distinguished by substantial kinking at the drug binding site. The oligomers were 20 bases in length, which was too short to permit the kinking angle to be determined with precision. However, models with a 45 degree kink gave a better fit to the images of the duplex adducts than models with a 90 degrees kink. A variety of structures was observed for the single-stranded adducts.
Isolation of a Bacterial Culture That Degrades Methyl t -Butyl Ether (1994)

We have isolated a mixed bacterial culture (BC-1) which is capable of degrading the gasoline oxygenate methyl t-butyl ether (MTBE). BC-1 was developed from seed microorganisms present in a chemical plant biotreater sludge. This enrichment culture has been maintained in continuous culture treating high concentrations of MTBE (120 to 200 mg/liter) as the sole carbon source in a simple feed containing NH(4), PO(4), Mg, and Ca nutrients. The unit had a stable MTBE removal rate when maintained with a long cell retention time (ca. 80 to 90 days); however, when operated at a </=50-day cell waste rate, loss of MTBE-degrading activity was observed. The following three noteworthy experimental data show that MTBE is biodegraded extensively by BC-1: (i) the continuous (oxygen-sparged) culture was able to sustain a population of autotrophic ammonia-oxidizing bacteria which could nitrify influent NH(4) concentrations at high rates and obtain CO(2) (sole carbon source for growth) from the metabolism of the alkyl ether, (ii) BC-1 metabolized radiolabeled either (CH(3)O-MTBE) to CO(2) (40%) and C-labeled cells (40%), and (iii) cell suspensions of the culture were capable of degrading (substrate depletion experiments) MTBE to t-butyl alcohol, a primary metabolite of MTBE. BC-1 is a mixed culture containing several bacterial species and is the first culture of its kind which can completely degrade an alkyl ether.
Validation of minimal disease activity criteria for psoriatic arthritis using interventional trial data (2010)

Patients with active PsA achieving MDA with effective therapy have a significant reduction in radiographic progression. Aiming for low levels of disease activity can improve the outcome of patients with PsA even in a disease-modifying antirheumatic drug-resistant cohort. The new MDA criteria could provide an objective target for treatment in trials and clinical practice.
ADVERSE REACTIONS IN CHILDREN VACCINATED WITH DPT AND PERTUSSIS VACCINE (1982)

A total of 508 children were vaccinated with DPT vaccine (Lot 76 327). The vaccination policy was that basic DPT vaccination started at the age of three months and three injections were given at one‐month intervals. In another 370 cases pertussis vaccine (Lot 76 012) was given. In these, vaccination started at the age of five weeks and three injections were given at four‐week intervals. In the children basically vaccinated with DPT vaccine some local reactions occurred in 26/508(5.1%) cases and systemic reactions in 48/508(9.4%). In the children basically vaccinated with pertussis vaccine local reactions occurred in 13/370(3.5%) cases and systemic reactions in 33/370(8.9%). Booster vaccination with DPT vaccine (Lot 76 327) was given to 565 children aged one–6 years, while 138 children aged 2–6 years were booster vaccinated with pertussis vaccine (Lot 76 012). The children booster vaccinated with DPT vaccine exhibited some local reactions in 118/565(20.9%) cases and some systemic reactions in 53/565(9.3%). In the children vaccinated with pertussis vaccine local reactions occurred in 14/138(10.1%) cases and systemic reactions in 7/138(5.1%). None of the vaccinated children developed any severe neurological or systemic complications from vaccination. DPT and pertussis vaccine contain equal amounts (about 5 000 million cells/ml vaccine) of the Bordetella pertussis strains 18 530 and 1 772 and aluminium hydroxy phosphate as adjuvant. One dose vaccine was 0.5 ml.
Dioxygen Activation and Methane Hydroxylation by Soluble Methane Monooxygenase: A Tale of Two Irons and Three Proteins (2001)

Methanotrophic bacteria are capable of using methane as their sole source of carbon and energy. The first step in methane metabolism, the oxidation of methane to methanol, is catalyzed by a fascinating enzyme system called methane monooxygenase (MMO). The selective oxidation of the very stable C-H bond in methane under ambient conditions is a remarkable feat that has not yet been repeated by synthetic catalysts and has attracted considerable scientific and commercial interest. The best studied MMO is a complex enzyme system that consists of three soluble protein components, all of which are required for efficient catalysis. Dioxygen activation and subsequent methane hydroxylation are catalyzed by a hydroxylase enzyme that contains a non-heme diiron site. A reductase protein accepts electrons from NADH and transfers them to the hydroxylase where they are used for the reductive activation of O(2). The third protein component couples electron and dioxygen consumption with methane oxidation. In this review we examine different aspects of catalysis by the MMO proteins, including the mechanisms of dioxygen activation at the diiron site and substrate hydroxylation by the activated oxygen species. We also discuss the role of complex formation between the different protein components in regulating various aspects of catalysis.
Andrew: a distributed personal computing environment (1986)

The Information Technology Center (ITC), a collaborative effort between IBM and Carnegie-Mellon University, is in the process of creating Andrew, a prototype computing and communication system for universities. This article traces the origins of Andrew, discusses its goals and strategies, and gives an overview of the current status of its implementation and usage.
Spatio-temporal EEG source localization using a three-dimensional subspace FINE approach in a realistic geometry inhomogeneous head model (2006)

The subspace source localization approach, i.e., first principle vectors (FINE), is able to enhance the spatial resolvability and localization accuracy for closely-spaced neural sources from EEG and MEG measurements. Computer simulations were conducted to evaluate the performance of the FINE algorithm in an inhomogeneous realistic geometry head model under a variety of conditions. The source localization abilities of FINE were examined at different cortical regions and at different depths. The present computer simulation results indicate that FINE has enhanced source localization capability, as compared with MUSIC and RAP-MUSIC, when sources are closely spaced, highly noise-contaminated, or inter-correlated. The source localization accuracy of FINE is better, for closely-spaced sources, than MUSIC at various noise levels, i.e., signal-to-noise ratio (SNR) from 6 dB to 16 dB, and RAP-MUSIC at relatively low noise levels, i.e., 6 dB to 12 dB. The FINE approach has been further applied to localize brain sources of motor potentials, obtained during the finger tapping tasks in a human subject. The experimental results suggest that the detailed neural activity distribution could be revealed by FINE. The present study suggests that FINE provides enhanced performance in localizing multiple closely spaced, and inter-correlated sources under low SNR, and may become an important alternative to brain source localization from EEG or MEG.
Inhibition of nicotine-induced seizures in rats by combining vaccination against nicotine with chronic nicotine infusion. (2001)

The ability of a nicotine vaccine to protect against nicotine-induced seizures was studied in rats. Groups of 10 rats were vaccinated with 3 doses of either a nicotine conjugate vaccine over 6 weeks to elicit high titers of nicotine-specific antibodies or with a control vaccine. Rats were then pretreated with a 1-week subcutaneous infusion of either nicotine 1 mg/kg/day or saline and then received a single 2 mg/kg ip dose of nicotine to provoke seizures. Vaccination reduced the incidence of seizures. The combination of vaccination and pretreatment with nicotine infusion was more effective than either treatment alone. These data suggest that vaccination is protective against this toxic effect of nicotine and that combining vaccination and chronic nicotine administration may provide a novel strategy for blocking some effects of nicotine.
Bevacizumab-Induced Normalization of Blood Vessels in Tumors Hampers Antibody Uptake (2013)

In solid tumors, angiogenesis occurs in the setting of a defective vasculature and impaired lymphatic drainage that is associated with increased vascular permeability and enhanced tumor permeability. These universal aspects of the tumor microenvironment can have a marked influence on intratumoral drug delivery that may often be underappreciated. In this study, we investigated the effect of blood vessel normalization in tumors by the antiangiogenic drug bevacizumab on antibody uptake by tumors. In mouse xenograft models of human ovarian and esophageal cancer (SKOV-3 and OE19), we evaluated antibody uptake in tumors by positron emission tomographic imaging 24 and 144 hours after injection of (89)Zr-trastuzumab (SKOV-3 and OE19), (89)Zr-bevacizumab (SKOV-3), or (89)Zr-IgG (SKOV-3) before or after treatment with bevacizumab. Intratumor distribution was assessed by fluorescence microscopy along with mean vessel density (MVD) and vessel normalization. Notably, bevacizumab treatment decreased tumor uptake and intratumoral accumulation compared with baseline in the tumor models relative to controls. Bevacizumab treatment also reduced MVD in tumors and increased vessel pericyte coverage. These findings are clinically important, suggesting caution in designing combinatorial trials with therapeutic antibodies due to a possible reduction in tumoral accumulation that may be caused by bevacizumab cotreatment.
Synthesis and Activity of Ruthenium Olefin Metathesis Catalysts Coordinated with Thiazol-2-ylidene Ligands (2008)

A new family of ruthenium-based olefin metathesis catalysts bearing a series of thiazole-2-ylidene ligands has been prepared. These complexes are readily accessible in one step from commercially available (PCy3)2Cl2Ru=CHPh or (PCy3)Cl2Ru=CH(o-iPrO-Ph) and have been fully characterized. The X-ray crystal structures of four of these complexes are disclosed. In the solid state, the aryl substituents of the thiazole-2-ylidene ligands are located above the empty coordination site of the ruthenium center. Despite the decreased steric bulk of their ligands, all of the complexes reported herein efficiently promote benchmark olefin metathesis reactions such as the ring-closing of diethyldiallyl and diethylallylmethallyl malonate and the ring-opening metathesis polymerization of 1,5-cyclooctadiene and norbornene, as well as the cross metathesis of allyl benzene with cis-1,4-diacetoxy-2-butene and the macrocyclic ring-closing of a 14-membered lactone. The phosphine-free catalysts of this family are more stable than their phosphine-containing counterparts, exhibiting pseudo-first-order kinetics in the ring-closing of diethyldiallyl malonate. Upon removing the steric bulk from the ortho positions of the N-aryl group of the thiazole-2-ylidene ligands, the phosphine-free catalysts lose stability, but when the substituents become too bulky the resulting catalysts show prolonged induction periods. Among five thiazole-2-ylidene ligands examined, 3-(2,4,6-trimethylphenyl)- and 3-(2,6-diethylphenyl)-4,5-dimethylthiazol-2-ylidene afforded the most efficient and stable catalysts. In the cross metathesis reaction of allyl benzene with cis-1,4-diacetoxy-2-butene increasing the steric bulk at the ortho positions of the N-aryl substituents results in catalysts that are more Z-selective.