gebhart/patrepeval huggingface dataset:
A regiospecific monooxygenase with novel stereopreference is the major pathway for arachidonic acid oxygenation in isolated epidermal cells. (1989)

We investigated the enzymatic mechanisms responsible for AA oxygenation in homogenous cell suspensions obtained by trypsinization of epidermis from healthy subjects. Cell incubation with AA (0.3-150 microM) invariably resulted in the predominant generation of a compound identified as 12-hydroxyeicosatetraenoic acid (12-HETE) by HPLC and by both negative-ion chemical ionization and electron-impact mass spectrometry. Maximal amounts of 12-HETE were 126 +/- 21 pmol/10(6) cells (+/- SE), and concentration-response curves yielded half-maximal levels for 12-HETE similar to PGE2 at 2 microM AA. Two epoxyeicosatrienoic acids derived from AA were also identified. Stereochemical analysis by chiral-phase chromatography demonstrated that the epidermal cell 12-HETE was a mixture of the 12S- and 12R-hydroxy isomers in a molar ratio varying from 2:1 to 8:1 among subjects. Subcellular fractionation into 12,000 g pellet (containing mitochondria) and 100,000 g supernatant (cytosol) and pellet (microsome) demonstrated that greater than 99% of the 12-HETE was generated by enzymatic activity distributed equally in the two pellets. Both mitochondrial and microsomal activities were increased upon addition of NADPH and were inhibited by carbon monoxide, but the molar ratio of 12S/12R-HETE was threefold greater in microsomal than in mitochondrial fractions. The results demonstrate that human epidermis contains active membrane-bound monooxygenase(s) which preferentially generates 12-HETE from AA, exhibits a 12S stereopreference of hydroxylation, and suggests the presence of distinct mitochondrial and microsomal enzyme systems in epidermal cells.
Comparison of XeF2 and F-atom reactions with Si and SiO2 (1984)

Silicon gasification by XeF2 is compared with F-atom etching under conditions typical of those used in plasma etching. Temperatures ranged from −17 to 360 °C and XeF2 pressures were between 0.05 and 2 Torr. Silicon etching by XeF2 shows a sharply different etch rate/temperature dependence than the Si/F or Si/F2 reaction systems; there is no detectable reaction between XeF2 and SiO2 in contrast to the F-atom/SiO2 system. These data indicate that physisorption can limit silicon etching by XeF2 and show that basic studies which use XeF2 as a model compound for the etching of silicon and SiO2 by F atoms should be interpreted with caution.
Psilocybin und Psilocin, zwei psychotrope Wirkstoffe aus mexikanischen Rauschpilzen (1959)

Abstract The psychotropically active principles of the Mexican hallucinogenic fungus Psilocybe maxicana H EIM have been isolated and obtained in crystalline form. The two new substances, which have been called psilocybin and psilocin , are present in the fruit bodies, the artificially cultivated mycelium and in the sclerotia. The dried mushroom contains 0.2 to 0.4 per cent psilocybin. Psilocin is present, at the most, in trace amounts only.
Silica Sol as a Nanoglue: Flexible Synthesis of Composite Aerogels (1999)

Low-density nanoscale mesoporous composites may be readily synthesized by adding a colloidal or dispersed solid to an about-to-gel silica sol. The silica sol can "glue" a range of chemically and physically diverse particles into the three-dimensional silica network formed upon gelation. If the composite gel is supercritically dried so as to maintain the high porosity of the wet gel, a composite aerogel is formed in which the nanoscopic surface and bulk properties of each component are retained in the solid composite. The volume fraction of the second solid can be varied above or below a percolation threshold to tune the transport properties of the composite aerogel and thereby design nanoscale materials for chemical, electronic, and optical applications.
Parkin Accumulation in Aggresomes Due to Proteasome Impairment (2002)

Parkinson's disease (PD) is characterized by loss of dopaminergic neurons in the substantia nigra and by the presence of ubiquitinated cytoplasmic inclusions known as Lewy bodies. Alpha-synuclein and Parkin are two of the proteins associated with inherited forms of PD and are found in Lewy bodies. Whereas numerous reports indicate the tendency of alpha-synuclein to aggregate both in vitro and in vivo, no information is available about similar physical properties for Parkin. Here we show that overexpression of Parkin in the presence of proteasome inhibitors leads to the formation of aggresome-like perinuclear inclusions. These eosinophilic inclusions share many characteristics with Lewy bodies, including a core and halo organization, immunoreactivity to ubiquitin, alpha-synuclein, synphilin-1, Parkin, molecular chaperones, and proteasome subunit as well as staining of some with thioflavin S. We propose that the process of Lewy body formation may be akin to that of aggresome-like structures. The tendency of wild-type Parkin to aggregate and form inclusions may have implications for the pathogenesis of sporadic PD.
β-Secretase Processing of the β-Amyloid Precursor Protein in Transgenic Mice Is Efficient in Neurons but Inefficient in Astrocytes (1996)

Alzheimer's disease is characterized by the extracellular deposition of beta-amyloid peptide (Abeta) in cerebral plaques and evidence is accumulating that amyloid is neurotoxic. Abeta is derived from the beta-amyloid precursor protein (APP). Proteolytic processing of APP by the enzyme, beta-secretase, produces the N terminus of Abeta, and releases a secreted ectodomain of APP (beta-s-APP). To develop animal models for measuring beta-secretase activity in specific brain cells in vivo, we have targeted the expression of the full-length human APP to either neurons or astrocytes in transgenic mice using the neuron- specific enolase (NSE) promoter or a modified glial fibrillary acidic protein (GFAP) gene, respectively. The APP cDNAs expressed were mutated (KM to NL at 670/671) to encode amino acid substitutions that enhance amyloidogenic processing in vitro. Western analyses revealed abundant production of beta-s-APP in the brains of NSE-APP mice and enzyme-linked immunosorbent assay analyses showed production of Abeta in fetal primary mixed brain cultures and brain homogenates from these transgenic animals. Because the NSE promoter drives expression primarily in neurons, this provides in vivo evidence that the beta-secretase cleavage necessary for generation of beta-s-APP and Abeta is efficiently performed in neurons. In contrast, only little beta-s-APP was detected in brain homogenates of GFAP-APP mice, indicating that astrocytes show very little beta-secretase activity in vivo. This provides strong in vivo evidence that the major source of Abeta in brain is from neurons and not from astrocytes.
Interferon γ induces differential upregulation of α and β chemokine secretion in colonic epithelial cell lines (1998)

These studies suggest that intestinal epithelial cells may produce chemokines capable of attracting both neutrophils and monocytes. The ability of IFN-gamma to activate the expression of beta chemokines preferentially could facilitate the development of chronic inflammatory infiltrates.
Mechanistic Studies on the Galvanic Replacement Reaction between Multiply Twinned Particles of Ag and HAuCl4 in an Organic Medium (2007)

This article presents a mechanistic study on the galvanic replacement reaction between 11- and 14-nm multiply twinned particles (MTPs) of Ag and HAuCl4 in chloroform. We monitored both morphological and spectral changes as the molar ratio of HAuCl4 to Ag was increased. The details of reaction were different from previous observations on single-crystal Ag nanocubes and cuboctahedrons. Because Au and Ag form alloys rapidly within small MTPs rich in vacancy and grain boundary defects, a complete Au shell did not form on the surface of each individual Ag template. Instead, the replacement reaction resulted in the formation of alloy nanorings and nanocages from Ag MTPs of decahedral or icosahedral shape. For the nanorings and nanocages derived from 11-nm Ag MTPs, the surface plasmon resonance (SPR) peak can be continuously shifted from 400 to 616 nm. When the size of Ag MTPs was increased to 14 nm, the SPR peak can be further shifted to 740 nm, a wavelength sought by biomedical applications. We have also investigated the effects of capping ligands and AgCl precipitate on the replacement reaction. While hollow structures were routinely generated from oleylamine-capped Ag MTPs, we obtained very few hollow structures by using a stronger capping ligand such as oleic acid or tri-n-octylphosphine oxide (TOPO). Addition of extra oleylamine was found to be critical to the formation of well-controlled, uniform hollow structures free of AgCl contamination thanks to the formation of a soluble complex between AgCl and oleylamine.
A new member of the acid-sensing ion channel family (2000)

Acid-sensing ion channels (ASICs) are members of the epithelial sodium channel (ENaC)-degenerin family of two-pass transmembrane segment protein subunits which form multimeric cation channels. Members of the ENaC-degenerin family are gated by stimuli as diverse as protons, peptides and mechanical distension. Here we describe a new member of the family, SPASIC or ASIC 4 (spinal cord ASIC) which is expressed throughout the central nervous system in an overlapping population of neurons that also express the ASIC subunit MDEG2. ASIC-4 which shows 44% identify with ASIC is developmentally regulated and expressed in a subset of sensory neurons as well as in the CNS. However, despite the strong homology with ASIC, the ASIC-4 transcript does not encode a proton gated cation channel.
A Markov Model for Driver Turn Prediction (2008)

&lt;div class="htmlview paragraph"&gt;This paper describes an algorithm for making short-term route predictions for vehicle drivers. It uses a simple Markov model to make probabilistic predictions by looking at a driver's just-driven path. The model is trained from the driver's long term trip history from GPS data. We envision applications including driver warnings, anticipatory information delivery, and various automatic vehicle behaviors. The algorithm is based on discrete road segments, whose average length is 237.5 meters. In one instantiation, the algorithm can predict the next road segment with 90% accuracy. We explore variations of the algorithm and find one that is both simple and accurate.&lt;/div&gt;
QUANTUM DOTS ARE PHAGOCYTIZED BY MACROPHAGES AND COLOCALIZE WITH EXPERIMENTAL GLIOMAS (2007)

Quantum dots are optical nanoparticles that, when delivered in nanomole doses, are phagocytized by the macrophages and microglia that infiltrate experimental gliomas. The optical signal may be detected, allowing for improved identification and visualization of tumors, potentially augmenting brain tumor biopsy and resection.
The Impact of Semiconductor Technology Scaling on CMOS RF and Digital Circuits for Wireless Application (2005)

The impact of CMOS technology scaling on the various radio frequency (RF) circuit components such as active, passive and digital circuits is presented. Firstly, the impact of technology scaling on the noise and linearity of the low-noise amplifier (LNA) is thoroughly analyzed. Then two new circuits, i.e., CMOS complementary parallel push-pull (CCPP) circuit and vertical-NPN (V-NPN) circuit for direct-conversion receiver (DCR), are introduced. In CCPP, the high RF performance of pMOS comparable to nMOS provides single ended differential RF signal processing capability without the use of a bulky balun. The use of parasitic V-NPN bipolar transistor, available in triple well CMOS technology, has shown to provide more than an order of magnitude improvement in 1/f noise and dc offset related problems, which have been the bottleneck for CMOS single chip integration. Then CMOS technology scaling for various passive device performances such as the inductor, varactor, MIM capacitor, and switched capacitor, is discussed. Both the forward scaling of the active devices and the inverse scaling of interconnection layer, i.e., more interconnection layers with effectively thicker total dielectric and metal layers, provide very favorable scenario for all passive devices. Finally, the impact of CMOS scaling on the various digital circuits is introduced, taking the digital modem blocks, the various digital calibration circuits, the switching RF power amplifier, and eventually the software defined radio, as examples.
Homologous recombination catalyzed by human cell extracts. (1985)

Two plasmids containing noncomplementing and nonreverting deletions in a bacterial phosphotransferase gene conferring resistance to neomycin (Neor) were incubated with human cell extracts, and the mixtures were used to transform recombination-deficient (recA-) Escherichia coli cells. We were able to obtain Neor colonies at a frequency of 2 X 10(-3). This frequency was 100 to 1,000 times higher than that obtained with no extracts. The removal of riboadenosine 5'-triphosphate, Mg2+, or deoxynucleoside triphosphates from the reaction mixture severely reduced the yield of Neor colonies. Examination of plasmid DNA from the Neor colonies revealed that they resulted from gene conversion and reciprocal recombination. On the basis of these results, we conclude that mammalian somatic cells in culture have the enzymatic machinery to catalyze homologous recombination in vitro.
Pyrazine Chemistry. III. Derivatives of 3-Amino-5,6-dimethylpyrazinoic Acid (1948)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPyrazine Chemistry. III. Derivatives of 3-Amino-5,6-dimethylpyrazinoic AcidRudolph C. Ellingson and Robert L. HenryCite this: J. Am. Chem. Soc. 1948, 70, 3, 1257–1261Publication Date (Print):March 1, 1948Publication History Published online1 May 2002Published inissue 1 March 1948https://pubs.acs.org/doi/10.1021/ja01183a117https://doi.org/10.1021/ja01183a117research-articleACS PublicationsRequest reuse permissionsArticle Views207Altmetric-Citations9LEARN 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
Fibroblast‐like synoviocytes: key effector cells in rheumatoid arthritis (2009)

Rheumatoid arthritis (RA) remains a significant unmet medical need despite significant therapeutic advances. The pathogenesis of RA is complex and includes many cell types, including T cells, B cells, and macrophages. Fibroblast-like synoviocytes (FLS) in the synovial intimal lining also play a key role by producing cytokines that perpetuate inflammation and proteases that contribute to cartilage destruction. Rheumatoid FLS develop a unique aggressive phenotype that increases invasiveness into the extracellular matrix and further exacerbates joint damage. Recent advances in understanding the biology of FLS, including their regulation regulate innate immune responses and activation of intracellular signaling mechanisms that control their behavior, provide novel insights into disease mechanisms. New agents that target FLS could potentially complement the current therapies without major deleterious effect on adaptive immune responses.
Toxicity of Organic Fluorophores Used in Molecular Imaging: Literature Review (2009)

Fluorophores are potentially useful for in vivo cancer diagnosis. Using relatively inexpensive and portable equipment, optical imaging with fluorophores permits real-time detection of cancer. However, fluorophores can be toxic and must be investigated before they can be administered safely to patients. A review of published literature on the toxicity of 19 widely used fluorophores was conducted by searching 26 comprehensive biomedical and chemical literature databases and analyzing the retrieved material. These fluorophores included Alexa Fluor 488 and 514, BODIPY FL, BODIPY R6G, Cy 5.5, Cy 7, cypate, fluorescein, indocyanine green, Oregon green, 8-phenyl BODIPY, rhodamine 110, rhodamine 6G, rhodamine X, rhodol, TAMRA, Texas red, and Tokyo green. Information regarding cytotoxicity, tissue toxicity, in vivo toxicity, and mutagenicity was included. Considerable toxicity-related information was available for the Food and Drug Administration (FDA)-approved compounds indocyanine green and fluorescein, but published information on many of the non-FDA-approved fluorophores was limited. The information located was encouraging because the amounts of fluorophore used in molecular imaging probes are typically much lower than the toxic doses described in the literature. Ultimately, the most effective and appropriate probes for use in patients will be determined by their fluorescent characteristics and the safety of the conjugates.
Multi-scale lung modeling (2011)

Multi-scale modeling of biological systems has recently become fashionable due to the growing power of digital computers as well as to the growing realization that integrative systems behavior is as important to life as is the genome. While it is true that the behavior of a living organism must ultimately be traceable to all its components and their myriad interactions, attempting to codify this in its entirety in a model misses the insights gained from understanding how collections of system components at one level of scale conspire to produce qualitatively different behavior at higher levels. The essence of multi-scale modeling thus lies not in the inclusion of every conceivable biological detail, but rather in the judicious selection of emergent phenomena appropriate to the level of scale being modeled. These principles are exemplified in recent computational models of the lung. Airways responsiveness, for example, is an organ-level manifestation of events that begin at the molecular level within airway smooth muscle cells, yet it is not necessary to invoke all these molecular events to accurately describe the contraction dynamics of a cell, nor is it necessary to invoke all phenomena observable at the level of the cell to account for the changes in overall lung function that occur following methacholine challenge. Similarly, the regulation of pulmonary vascular tone has complex origins within the individual smooth muscle cells that line the blood vessels but, again, many of the fine details of cell behavior average out at the level of the organ to produce an effect on pulmonary vascular pressure that can be described in much simpler terms. The art of multi-scale lung modeling thus reduces not to being limitlessly inclusive, but rather to knowing what biological details to leave out.
Immunity to Distinct Sand Fly Salivary Proteins Primes the Anti-Leishmania Immune Response towards Protection or Exacerbation of Disease (2008)

Immunization with two salivary proteins from P. papatasi, PpSP15 and PpSP44, produced distinct immune profiles that correlated with resistance or susceptibility to Leishmania infection. The demonstration for the first time that immunity to a defined salivary protein (PpSP44) results in disease enhancement stresses the importance of the proper selection of vector-based vaccine candidates.
Activation of muscle-specific transcription by myogenic helix-loop-helix proteins. (1992)

Myogenin is a muscle-specific transcription factor that acts as a molecular switch to induce myogenesis. Myogenin shares homology with MyoD and other myogenic regulatory proteins within a basic region and helix-loop-helix (HLH) motif that mediate binding to a conserved DNA sequence (CANNTG) present in the regulatory regions of numerous muscle-specific genes. Binding of myogenin and other members of the MyoD family to DNA can be augmented upon heterodimerization with the widely expressed HLH protein E12. We have used the muscle creatine kinase (MCK) enhancer as a target to study the mechanism whereby myogenin activates muscle-specific transcription. Full activity of the MCK enhancer requires cooperative interactions between myogenin (or other myogenic HLH proteins that bind the same site) and a complex array of ubiquitous and cell type-specific nuclear factors. To define the domains of myogenin responsible for sequence-specific DNA binding, activation of muscle-specific transcription, and cooperativity with other transcription factors, we have generated an extensive series of mutants by site-directed mutagenesis and domain swapping. These mutants have revealed strong transcriptional activation domains in the N- and C-termini of myogenin that rely on a specific amino acid sequence within the DNA binding domain for activity. Myogenin's ability to induce muscle-specific transcription is subject to negative regulation by growth factor and oncogenic signals. Mechanisms through which growth signals may repress myogenin function are discussed.
Use of Organosilicon Reagents as Protective Groups in Organic Synthesis (1985)

Recent developments in the use of organosilicon reagents for the protection of organic functional groups involving hetero atoms are discussed. Conditions of protection and deprotection are described as well as the selectivity of the reagents. 1. Protection for the Hydroxy Group 2. Protection for 1,2- and 1,3-Diols 3. Protection for the Carbonyl Group 4. Protection for the Carboxyl Group 5. Protection for the Amino Group 6. Protection for the Sulfur Atom 7. Protection for the Phosphorus Atom 8. Addendum 9. Conclusions
Interference in climbing a quantum ladder system with frequency-chirped laser pulses (1994)

Excitation of a quantum ladder system by frequency-swept (-chirped) laser pulses has been investigated by studying an atomic model system, the 5s-5p-5d ladder of rubidium. The population transfer is significantly enhanced when the frequency is swept such that it follows the spacing of the ladder. At intermediate intensities we observe oscillations in the population transfer to the upper level (5d), which can be attributed to interference between two routes of excitation: sequential transfer and direct two-photon excitation via a virtual intermediate state. We determine simultaneously the population transfer to the upper level (5d) and the direct three-photon ionization, the latter corresponding to a three-step ladder with the final state being in the continuum: 5s-5p-5d-\ensuremath{\varepsilon}p/\ensuremath{\varepsilon}f. Experiments were performed, using 100 fs pulses at \ensuremath{\sim}780 nm from a self-mode-locked Ti:${\mathrm{Al}}_{2}$${\mathrm{O}}_{3}$ oscillator amplified at 10 Hz.
The wavelet/scalar quantization compression standard for digital fingerprint images (2002)

A new digital image compression standard has been adopted by the US Federal Bureau of Investigation for use on digitized gray-scale fingerprint images. The algorithm is based on adaptive uniform scalar quantization of a discrete wavelet transform image decomposition and is referred to as the wavelet/scalar quantization standard. The standard produces archival quality images at compression ratios of around 20:1 and will allow the FBI to replace their current database of paper fingerprint cards with digital imagery.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>