gebhart/patrepeval huggingface dataset:
On the Mechanism of Inactivation of Xanthine Oxidase by Allopurinol and Other Pyrazolo[3,4-d]pyrimidines (1970)

Allopurinol and other 6-unsubstituted pyrazolo[3,4-d]-pyrimidines have been shown to reduce all of the oxidation-reduction reactive groups of milk xanthine oxidase. The great inhibitory action of these compounds has been shown to be due to a sort of suicide reaction, in which the product formed by enzymatic hydroxylation in position 6 is joined in complex with a partially reduced from of the enzyme. Several lines of evidence are presented indicating that complex formation is with the enzyme-bound molybdenum in the Mo(IV) state. Studies on the stoichiometry of binding of the product of allopurinol reaction, allo-xanthine(4,6-dihydroxypyrazolo[3,4-d]pyrimidine), revealed that the amount of allo-xanthine bound was proportional to the percentage of functional active sites in the enzyme preparation; i.e. it serves as an active site label. From these results it is concluded that the best preparations of xanthine oxidase so far obtained contain only 75 to 80% functional active sites, even though they possess their full complement of flavin, molybdenum, and iron-sulfur components. Evidence is presented that the presence of nonfunctional active sites is responsible for several of the slow reactions previously observed with the enzyme.
General synthesis of 3-(substituted benzoyl)-3-substituted alkanoic acids (1973)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGeneral synthesis of 3-(substituted benzoyl)-3-substituted alkanoic acidsFrancis J. McEvoy and George R. Allen Jr.Cite this: J. Org. Chem. 1973, 38, 23, 4044–4048Publication Date (Print):November 1, 1973Publication History Published online1 May 2002Published inissue 1 November 1973https://pubs.acs.org/doi/10.1021/jo00987a019https://doi.org/10.1021/jo00987a019research-articleACS PublicationsRequest reuse permissionsArticle Views180Altmetric-Citations16LEARN 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
A Taxonomy of Pairing-Friendly Elliptic Curves (2009)

Elliptic curves with small embedding degree and large prime-order subgroup are key ingredients for implementing pairing-based cryptographic systems. Such “pairing-friendly” curves are rare and thus require specific constructions. In this paper we give a single coherent framework that encompasses all of the constructions of pairing-friendly elliptic curves currently existing in the literature. We also include new constructions of pairing-friendly curves that improve on the previously known constructions for certain embedding degrees. Finally, for all embedding degrees up to 50, we provide recommendations as to which pairing-friendly curves to choose to best satisfy a variety of performance and security requirements.
Substrate specificity of beta-collagenase from Clostridium histolyticum. (1985)

The substrate specificity of beta-collagenase from Clostridium histolyticum has been investigated by measuring the rate of hydrolysis of more than 50 tri-, tetra-, penta-, and hexapeptides covering the P3 to P3' subsites of the substrate. The choice of peptides was patterned after sequences found in the alpha 1 and alpha 2 chains of type I collagen. Each peptide contained either a 2-furanacryloyl (FA) or cinnamoyl (CN) group in subsite P2 or the 4-nitrophenylalanine (Nph) residue in subsite P1. Hydrolysis of the P1-P1' bond produces an absorbance change in these chromophoric peptides that has been used to quantitate the rates of their hydrolysis under first order conditions ([S] much less than KM) from kcat/KM values have been obtained. The identity of the amino acids in all six subsites (P3-P3') markedly influences the hydrolysis rates. In general, the best substrates have Gly in subsites P3 and P1', Pro or Ala in subsite P2', and Hyp, Arg, or Ala in subsite P3'. This corresponds well with the frequency of occurrence of these residues in the Gly-X-Y triplets of collagen. In contrast, the most rapidly hydrolyzed substrates do not have residues from collagen-like sequences in subsites P2 and P1. For example, CN-Nph-Gly-Pro-Ala is the best known substrate for beta-collagenase with a kcat/KM value of 4.4 X 10(7) M-1 min-1, in spite of the fact that there is neither Pro nor Ala in P2 or Hyp nor Ala in P1. These results indicate that the previously established rules for the substrate specificity of the enzyme require modification.
<i>Trans</i> -Suppression of Misfolding in an Amyloid Disease (2001)

The transthyretin (TTR) amyloid diseases, representative of numerous misfolding disorders, are of considerable interest because there are mutations that cause or suppress disease. The Val30 --> Met30 (V30M) TTR mutation is the most prevalent cause of familial amyloid polyneuropathy in heterozygotes, whereas a Thr119 --> Met119 (T119M) mutation on the second TTR allele protects V30M carriers from disease. Here, we show that the incorporation of one or more T119M TTR subunits into a predominantly V30M tetramer strongly stabilized the mixed tetramer against dissociation. Dissociation is required for amyloid formation, so these findings provide a molecular explanation for intragenic trans-suppression of amyloidosis. The data also suggest a potential therapeutic strategy, provide insight into tissue-specific deposition and amyloid composition, and support the validity of the amyloid hypothesis in human disease.
Purification and Properties of In Vitro–produced Anthrax Toxin Components (1968)

The three components of the toxin of Bacillus anthracis, edema factor (EF), protective antigen (PA), and lethal factor (LF), were purified 197-, 156-, and 1,025- fold, with 38, 78, and 11% recovery, respectively. Each purified component was serologically active, distinct, and free from the other components. The purified EF produced edema when mixed with PA, and the purified PA was an active immunogen. The components did not appear to be simple proteins by spectrophotometric analysis. As they were purified, the pH range in which they were most stable narrowed, centering between pH 7.4 and 7.8. Heat readily destroyed the biological activity of the components but not their serological activity. The rat lethality test showed that, with a constant amount of LF and an increasing amount of PA, the time to death reached a minimum and then was extended. When an increasing amount of LF was added to a constant amount of PA, the time to death became shorter as more LF was added. The biological, immunological, and serological properties of the components were shown to vary independently with storage and extent of purification so that serological activity was not always directly correlated with biological activity. Evidence is presented that the components can exist in different molecular configurations or as aggregates, and that this property is influenced by the state of component purity and by the environment.
Analogs of angiotensin II. II. Mechanism of receptor interaction (1970)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAnalogs of angiotensin II. II. Mechanism of receptor interactionPhilip A. Khairallah, A. Toth, and F. M. BumpusCite this: J. Med. Chem. 1970, 13, 2, 181–184Publication Date (Print):March 1, 1970Publication History Published online1 May 2002Published inissue 1 March 1970https://pubs.acs.org/doi/10.1021/jm00296a003https://doi.org/10.1021/jm00296a003research-articleACS PublicationsRequest reuse permissionsArticle Views89Altmetric-Citations48LEARN 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
The ergonomic and safety implications of in-car ATT devices - evidence from field trials with elderly drivers (1995)

The DRIVE II project EDDIT (Elderly and Disabled Drivers' Information Telematics) has evaluated a number of in-vehicle telematic systems in terms of their potential value in extending the safe driving life of the elderly. Although the terms of reference of the project focus on the benefits and safety implications for what appears to be a particularly vulnerable group-the over-65s- EDDIT's experimental work has provided valuable insights into ergonomic issues that concern all users, and has highlighted both the usefulness and usability of different types of man-machine interface. Among the devices tested have been two reversing aids (one dashboard-mounted, the other located behind the driver), three types of route guidance system and a head-up night vision enhancement system. Unlike other in-vehicle innovations, such as mobile telephones and music systems, the systems studied within EDDIT add another element to the driving task, leading potentially to an increase in the driver's visual and mental workload, and many of them require the user to switch his/her visual attention from the road scene ahead. The possible safety implications of using such devices are therefore very important, particularly in the case of elderly people, whose capacity to cope with the various mental and cognitive demands of driving may in any case be almost saturated. This paper discusses these issues in the light of the results of EDDIT'S field trials.
A Survey on Edge Computing Systems and Tools (2019)

Driven by the visions of Internet of Things and 5G communications, the edge computing systems integrate computing, storage, and network resources at the edge of the network to provide computing infrastructure, enabling developers to quickly develop and deploy edge applications. At present, the edge computing systems have received widespread attention in both industry and academia. To explore new research opportunities and assist users in selecting suitable edge computing systems for specific applications, this survey paper provides a comprehensive overview of the existing edge computing systems and introduces representative projects. A comparison of open-source tools is presented according to their applicability. Finally, we highlight energy efficiency and deep learning optimization of edge computing systems. Open issues for analyzing and designing an edge computing system are also studied in this paper.
Ventricular Septal Defects (2007)

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Acid-Catalyzed Isomerization of Carvone to Carvacrol (2005)

The acid-catalyzed isomerization of carvone (oil of spearmint) to carvacrol (oil of origanum) in the sophomore organic chemistry laboratory is discussed. The experiment demonstrates several important concepts including (i) formation of a carbocation by protonation of an alkene, (ii) rearrangement of a carbocation, (iii) deprotonation of a carbocation, (iv) acid-catalyzed enolization, and (v) aromaticity. The experiment is especially suitable for use with low-field permanent-magnet FT–NMR for two important reasons: (i) even the 60 MHz proton spectrum is interpretable by the students and (ii) the product is a liquid that is obtained from an inexpensive starting material in sufficiently high yield and purity so that a neat or highly concentrated NMR sample can be prepared for 13C NMR analysis.
Observation of Mobility Enhancement in Strained Si and SiGe Tri-Gate MOSFETs with Multi-Nanowire Channels Trimmed by Hydrogen Thermal Etching (2007)

Strained Si and SiGe tri-gate nanowire (NW) MOSFETs with significantly reduced line-edge roughness and smooth sidewalls were fabricated by a novel anisotropic thermal etching technique in H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> atmosphere. Effective carrier mobility measurements revealed mobility enhancements for the strained-Si NW n-MOSFETs and the strained-SiGe NW p-MOSFETs by factors of 1.9 and 1.6 against unstrained Si NW n- and p-MOSFETs, respectively. It was also shown that the sidewall shapes of the NWs have a great impact on the mobility via the difference in the surface roughness scattering on the sidewalls.
Microbicides and HIV prevention: lessons from the past, looking to the future (2009)

Development of a protective 'barrier' which can be controlled by the receptive partner independent of time of coitus remains a key goal in HIV prevention. A gel or ring-delivered combination of active anti-HIV agents may prove more efficacious than a single agent alone. Challenges in evaluating and manufacturing new candidates must be overcome before a well tolerated, effective, acceptable and affordable microbicide can be produced.
Vasoactive Intestinal Peptide Stimulation of Adenylate Cyclase and Active Electrolyte Secretion in Intestinal Mucosa (1974)

Vasoactive intestinal peptide (VIP), originally isolated from hog small intestinal mucosa, has been shown to cause small intestinal secretion. More recently, this peptide has been identified in the plasma and tumors of patients with the so-called "pancreatic cholera" syndrome. In order to explore the possible role of VIP in the pathogenesis of this syndrome, we examined the effects of this peptide and other hormones on the cyclic AMP levels, adenylate cyclase activity, and ion transport in in vitro preparations of ileal mucosa. In rabbit ileal mucosa, VIP (20 mug/ml) caused a prompt fivefold increase in cyclic AMP level, whereas nine other hormones, which have been postulated to cause intestinal secretion, failed to exert such an effect. Pentagastrin and glucagon also failed to increase cyclic AMP levels in canine ileal mucosa. An increase in mucosal cyclic AMP levels was observed at a VIP concentration of 0.1 mug/ml and appeared to be nearly maximal at 2.0 mug/ml. VIP (100 mug/ml) stimulated adenylate cyclase activity in a membrane preparation from rabbit ileal mucosa. Secretin (6.0 x 10(-5) M) failed to do so. When added to the serosal side of isolated rabbit ileal mucosa clamped in an Ussing chamber, VIP (2 mug/ml) increased short-circuit current (SCC) and caused net secretion of both Cl and Na. Net Cl secretion exceeded net Na secretion. These effects of VIP on mucosal cyclic AMP metabolism and ion transport are similar to those observed with cholera enterotoxin and certain prostaglandins. VIP was also tested with normal human ileal mucosa. At a concentration of 2 mug/ml it caused a fivefold increase in cyclic AMP level and an increase in SCC of the same magnitude as that caused by 5 mM theophylline. Addition of a second 2-mug/ml dose of VIP and addition of theophylline after VIP produced no further change in SCC. We conclude the VIP stimulates adenylate cyclase and active ion secretion in both rabbit and human ileal mucosa. This may be related to the pathogenesis of diarrhea in patients with the pancreatic cholera syndrome.
An algorithm for robust signal modelling in speech recognition (2002)

The most popular set of parameters used in recognition systems is the mel frequency cepstral coefficients. While giving generally good results, it remains that the filtering process, as used in the evaluation of these parameters, reduces the signal resolution in the frequency domain, which can have some impact in discriminating between phonemes. This paper presents a new parameterization approach that preserves most of the characteristics of mel frequency cepstral coefficients while maintaining the initial frequency resolution obtained from the fast Fourier transform. It is shown, by the results obtained, that this technique can significantly increase the performance of a recognition system.
An Observation Chamber Technique for Evaluating Potential Biocontrol Agents of Globodera rostochiensis. (1984)

Recent research has stimulated optimism that naturally occurring parasites may be useful biocontrol agents of nematodes (3,4,6-9). To evaluate their potential, collections of biocontrol agents must be screened against the target nematode. Screening isolates against one nematode generation in greenhouse pots is an often used standard test. Disadvantages of this test include the lack of controlled environmental conditions and the inability, without destructive sampling, to observe the effect of parasitism. An observation chamber was developed (1) and used to continually observe parasitism of developing Heterodera avenae (Woll.) females by Nematophthora g),nophila (5). This technique involved growing oat roots in clear petri dishes in soil infested with both the nematode and the fungM parasite under greenhouse conditions. The observation chamber allowed evaluation of parasitism at more than one point in the life cycle, but lacked controlled environ
<i>In vitro</i> cultivation of human islets from expanded ductal tissue (2000)

A major obstacle to successful islet transplantation for both type 1 and 2 diabetes is an inadequate supply of insulin-producing tissue. This need for transplantable human islets has stimulated efforts to expand existing pancreatic islets and/or grow new ones. To test the hypothesis that human adult duct tissue could be expanded and differentiated in vitro to form islet cells, digested pancreatic tissue that is normally discarded from eight human islet isolations was cultured under conditions that allowed expansion of the ductal cells as a monolayer whereupon the cells were overlaid with a thin layer of Matrigel. With this manipulation, the monolayer of epithelial cells formed three-dimensional structures of ductal cysts from which 50-to 150- micrometer diameter islet-like clusters of pancreatic endocrine cells budded. Over 3-4 weeks culture the insulin content per flask increased 10- to 15-fold as the DNA content increased up to 7-fold. The cultivated human islet buds were shown by immunofluorescence to consist of cytokeratin 19-positive duct cells and hormone-positive islet cells. Double staining of insulin and non-beta cell hormones in occasional cells indicated immature cells still in the process of differentiation. Insulin secretion studies were done over 24 h in culture. Compared with their basal secretion at 5 mM glucose, cysts/cultivated human islet buds exposed to stimulatory 20 mM glucose had a 2.3-fold increase in secreted insulin. Thus, duct tissue from human pancreas can be expanded in culture and then be directed to differentiate into glucose responsive islet tissue in vitro. This approach may provide a potential new source of pancreatic islet cells for transplantation.
Dentin bond strength of a new adhesive system containing calcium phosphate experimentally developed for direct pulp capping (2009)

The purpose of this study was to evaluate the microtensile bond strength (microTBS) to human dentin of an experimental bonding agent containing calcium phosphates experimentally developed for direct pulp capping. Different concentrations of four types of calcium phosphates were added to an experimental bonding monomer, and six experimental bonding agents were thus prepared. Clearfil SE Bond/Bond was used as the control. Flat dentin surfaces of human molars were assigned to the experimental adhesive systems and the control. After Clearfil SE Bond/Primer was applied to the dentin surface, each experimental bonding agent was applied and photopolymerized, and then a resin composite paste was placed and photopolymerized. The specimens were subjected to microTBS testing. Results revealed that there were no significant differences among the microTBS values of the experimental bonding agents and the control. In other words, the calcium phosphate-containing experimental adhesives did not adversely affect the microTBS to dentin.
Identification of degradation products in Aripiprazole tablets by LC-QToF mass spectrometry (2010)

This paper describes the separation, identification and proposed structures of the degradation products formed during degradation analysis of aripiprazole in its final dosage form by high performance liquid chromatography (HPLC) coupled with quadrupole time-of-flight mass spectrometry (QToF-MS). The drug product was subjected to stress conditions including acid, base, thermal, oxidation, humidity and photolytic degradations. Aripiprazole was found to be stable in all conditions except in thermal and peroxide degradations. The degradation impurities were first separated by HPLC and then identified using QToF mass spectrometry. QToF mass spectrometer provided high order of mass accuracy for unknown impurities and their fragment ions to explore the elemental composition. Based on the fragmentation pattern, the possible structures of the unknown impurities were proposed. To the best of our knowledge, there were no methods available to identify the impurities during degradation of aripiprazole tablets by liquid chromatography-mass spectrometry.
Artificially Induced Epithelial-Mesenchymal Transition in Surgical Subjects: Its Implications in Clinical and Basic Cancer Research (2011)

This study will evoke the fundamental misinterpretation including underestimation of the prognostic evaluation power of markers by overestimation of EMT IN past cancer research, and will furnish some advice for the near future as follows: 1) Understanding how long the tissues were under an ischemic condition. 2) Prevalence of biopsy samples for in vivo expression profiling with low biases on basic and clinical research. 3) Checking cancer cell contents and normal- or necrotic-tissue contamination in biopsy samples for prevalence.