gebhart/patrepeval huggingface dataset:
Crystal Structure of the Wild-type von Willebrand Factor A1-Glycoprotein Ibα Complex Reveals Conformation Differences with a Complex Bearing von Willebrand Disease Mutations (2004)

The adhesion of platelets to the subendothelium of blood vessels at sites of vascular injury under high shear conditions is mediated by a direct interaction between the platelet receptor glycoprotein Ibalpha (GpIbalpha) and the A1 domain of the von Willebrand factor (VWF). Here we report the 2.6-A crystal structure of a complex comprised of the extracellular domain of GpIbalpha and the wild-type A1 domain of VWF. A direct comparison of this structure to a GpIbalpha-A1 complex containing "gain-of-function" mutations, A1-R543Q and GpIbalpha-M239V, reveals specific structural differences between these complexes at sites near the two GpIbalpha-A1 binding interfaces. At the smaller interface, differences in interaction show that the alpha1-beta2 loop of A1 serves as a conformational switch, alternating between an open alpha1-beta2 isomer that allows faster dissociation of GpIbalpha-A1, as observed in the wild-type complex, and an extended isomer that favors tight association as seen in the complex containing A1 with a type 2B von Willebrand Disease (VWD) mutation associated with spontaneous binding to GpIbalpha. At the larger interface, differences in interaction associated with the GpIbalpha-M239V platelet-type VWD mutation are minor and localized but feature discrete gamma-turn conformers at the loop end of the beta-hairpin structure. The beta-hairpin, stabilized by a strong classic gamma-turn as seen in the mutant complex, relates to the increased affinity of A1 binding, and the beta-hairpin with a weak inverse gamma-turn observed in the wild-type complex corresponds to the lower affinity state of GpIbalpha. These findings provide important details that add to our understanding of how both type 2B and platelet-type VWD mutations affect GpIbalpha-A1 binding affinity.
Low-frequency-noise diode laser for atom interferometry (2008)

We investigate the influence of fast frequency fluctuations of an interrogation laser on the obtainable signal-to-noise ratio in Ramsey-Bordé atom interferometers. It is shown that the excessive high-frequency noise of diode lasers can degrade the signal-to-noise ratio significantly in an atom interferometer. To overcome these limitations, we have devised a low-noise light source by frequency filtering a diode laser in a high-finesse cavity and further amplifying the transmitted power by injection locking a solitary laser diode. When this laser source was used for atom interferometry with laser-cooled calcium atoms, the signal-to-noise ratio could be improved further by a factor of 3.5 compared with the use of the unfiltered 1 Hz linewidth laser source.
Management and Monitoring of Cancer-Associated Retinopathy (1992)

Cancer-associated retinopathy is a rare paraneoplastic event that can involve allergic reactions and result in retinal degradation. A patient, who had a 35-year smoking history, complained of visual loss and was found to have serum antibodies that reacted with an extract of retina, including the previously described retinal cancer-associated retinopathy antigen. Prednisone treatment appeared to reduce the patient's antibody titers to normal levels. Visual fields stabilized, and the patient was able to maintain useful vision throughout the course of treatment until his death 1 year following initial diagnosis. To our knowledge, this is the first reported case in which monitoring of antibody responses to retinal antigens appeared to be useful in the decision whether to initiate prednisone therapy. Rising antibody titers to the cancer-associated retinopathy antigen probably occurs before progressive visual field loss and may be considered an indication for prompt steroid therapy.
Polymer-liposome nanoparticles obtained by the electrostatic bio-adsorption of natural polymers onto soybean lecithin liposomes (2012)

This work is focused on the formulation of polymer-liposome nanoparticles based on the electrostatic bio-adsorption of natural polymers onto soybean lecithin liposomes, with potential as novel delivery system for macromolecules, such as proteins. The building up of the polymer-liposome nanoparticles was achieved through the alternating bio-adsorption of natural cationic (chitosan) and neutral (dextran) or anionic (dextran sulphate or alginate) polymer layers on a core composed by anionic nanosized soybean lecithin liposomes. The electrostatic bio-adsorption of natural polymers succeeded in building nanosized, spherical, monodisperse and stable polymer-liposome nanoparticles with cumulative sizes between 357.3 nm ± 25.3 nm and 498.2 nm ± 69.6 nm and surface charges (ζ-potential) between –30.66 mV ± 1.55 mV and –26.74 mV ± 1.04 mV for the liposomal systems composed by alternating layers of chitosan and dextran sulphate or alginate, respectively. Natural-polymer-liposome nanoparticles offer good properties for encapsulation on its liposomal aqueous core and sustained release of a model protein, BSA, in vitro.
SCTP multistreaming: preferential treatment among stireams (2004)

FCS networks are presented with a new transport layer mechanism that, for transmitting multimedia, is markedly superior to transmission over UDP or TCP. SCTP's multistrearning provides an aggregation mechanism for transferring different objects belonging to the same logical application session; however, sharing the congestion state among the streams precludes efficient stream prioritization. We design an SCTP mechanism to provide the application with the service of being able to mark data such that different parts of a transfer (different streams) could be requested to receive preferential treatment from the network. The data flow within an association is divided into separate subassociation flows (SF), each SF having its own set of congestion control parameters. We implemented this design using an SCTP stack from Siemens. A number of experiments show that the streams marked with higher priority achieve much better throughput. We plan to investigate a layered congestion avoidance technique that uses state information from individual subflows to allow: dynamic addition of subflows without slow start; load balancing between paths and subflows; and using network state information to provide intelligent feedback to the application.
Design Formulas for Permanent-Magnet Bearings (2003)

As the energy densities in permanent magnet materials increases, permanent magnet (PM) bearings are becoming increasingly attractive machine elements for applications ranging from turbo machinery to energy storage flywheels. Desirable qualities include high speed, low wear, energy savings, and freedom from lubricants that can degrade or contaminate other system components. In this paper we develop analytical expressions for stiffness and peak load in stacked-structure radial magnetic bearings that extend the seminal work of Backers, and Yonnet and co-workers. In addition to the derivation of simple design rules, the axial peak force and negative axial stiffness are calculated.
Bit-rate enhancement through optical NRZ-to-RZconversion and passive time-division multiplexingfor soliton transmission systems (1994)

A nonlinear optical loop mirror is used to convert an NRZ signal generated by a standard 2.5 Gbit/s transmitter into a near-transform-limited 2.5 Gbit/s RZ signal. Passive time-division multiplexing is then used to enhance the signal bit rate up to 10 Gbit/s. This experiment shows the potential of using NRZ transmitters for high bit rate soliton system applications.
Analog integrated filters or continuous-time filters for LSI and VLSI (1987)

A survey is given on analog (continuous-time) filters for (V)LSI. The most important design methods, the filter elements on silicon (bipolar as well as MOS) and applications are briefly reviewed. Limitations and challenges to designers conclude the survey.
Anti-pig antibody adsorption efficacy of α-Gal carrying recombinant P-selectin glycoprotein ligand-1/immunoglobulin chimeras increases with core 2 β1, 6-N-acetylglucosaminyltransferase expression (2004)

We have previously described the construction of a P-selectin glycoprotein ligand-1-mouse immunoglobulin Fc fusion protein, which when transiently coexpressed with the porcine alpha1,3 galactosyltransferase in COS cells becomes a very efficient adsorber of xenoreactive, anti-pig antibodies. To relate the adsorption capacity with the glycan expression of individual fusion proteins produced in different cell lines, stable CHO-K1, COS, and 293T cells producing this fusion protein have been engineered. On alpha1,3 galactosyltransferase coexpression, high-affinity adsorbers were produced by both COS and 293T cells, whereas an adsorber of lower affinity was derived from CHO-K1 cells. Stable coexpression of a core 2 beta1,6 N-acetylglucosaminyltransferase in CHO-K1 cells led to increased alpha-Gal epitope density and improved anti-pig antibody adsorption efficacy. ESI-MS/MS of O-glycans released from PSGL-1/mIgG(2b) produced in an alpha1,3 galactosyl- and core 2 beta1,6 N-acetylglucosaminyltransferase expressing CHO-K1 cell clone revealed a number of structures with carbohydrate sequences consistent with terminal Gal-Gal. In contrast, no O-glycan structures with terminal Gal-Gal were identified on the fusion protein when expressed alone or in combination with the alpha1,3 galactosyltransferase in CHO-K1 cells. In conclusion, the density of alpha-Gal epitopes on PSGL-1/mIgG(2b) was dependent on the expression of O-linked glycans with core 2 structures and lactosamine extensions. The structural complexity of the terminal Gal-Gal expressing O-glycans with both neutral as well as sialic acid-containing structures is likely to contribute to the high adsorption efficacy.
Digital television transmission based on asynchronous transfer mode (2006)

This paper introduces a method to realize digital television transmission based on asynchronous transfer mode (ATM), a technology based on fast packet switching. Choosing the integral multiple length of an ATM cell payload to equal to the length of an MPEG transport stream packet, an MPEG transport stream packet can be inextenso loaded by several ATM cells and transformed into ATM cells. Using ATM virtual connection technology and B-ISDN, the interoperability between ATM and DTV may be realized, and DTV signal transmission may also be realized finally.
Thermoelectric single-photon detectors: isotropic Seebeck sensors (2003)

Energy transfer from hot-electrons to phonons at low temperatures may take a longer time than the duration of transient thermoelectric effect. In this time interval phonons are dynamically decoupled from hot-electron heat flux so that an effective enhancement of thermoelectric figure of merit takes place. Based on this conclusion, we developed a concept of single-photon microcalorimeter suitable for hyperspectral imaging at high photon counting rates.
Oxidative stress: damage to intact cells and organs (1985)

Oxidative cell damage can be monitored by detection of (a) photoemission of singlet molecular oxygen formed from radical interactions (so-called low-chemical chemiluminescence), (b) end products of lipid peroxidation, such as ethane, and (c) glutathione disulphide release. These methods, preferably used in a complementary fashion, provide insight into the pro-oxidant-antioxidant balance in the intact cell or organ. Recent work from this laboratory on the metabolism of hydroperoxides and aldehydes as well as on redox cycling of the quinone menadione is presented. The comparison of GSSG transport systems in liver and heart reveals a limitation of capacity in the latter, thus making GSSG export potentially critical in the heart. As part of an inter-organ feedback system between extrahepatic tissues and liver, the newly described hormone stimulation of GSH release from liver is also presented.
Molecular markers for osteoarthritis: the road ahead (2002)

Osteoarthritis is a disabling joint disease that is characterized by the progressive destruction of articular cartilage. Diagnosis is based on clinical symptoms in combination with radiography, which is relatively insensitive and provides only an indication of accumulated damage. Alternative methods, such as molecular markers, are therefore needed that can quantitatively, reliably, and sensitively detect osteoarthritic changes in the joints at an early stage of the disease. Such molecular markers are essential for diagnosis, prognosis, and monitoring of disease progression and efficacy of therapy that is targeted at joint destruction. In addition, these markers are important for the development of new disease-modifying therapies. This concise review discusses the developments over the past 2 years in the field of molecular markers for osteoarthritis.
Arylthioindoles, Potent Inhibitors of Tubulin Polymerization (2004)

Several arylthioindoles had excellent activity as inhibitors both of tubulin polymerization and of the growth of MCF-7 human breast carcinoma cells. Methyl 3-[(3,4,5-trimethoxyphenyl)thio]-5-methoxy-1H-indole-2-carboxylate (21), the most potent derivative, showed IC(50) = 2.0 microM, 1.6 times more active than colchicine and about as active as combretastatin A-4 (CSA4). Compound 21 inhibited the growth of the MCF-7 cells at IC(50) = 13 nM. Colchicine and CSA4 had 13 nM and 17 nM IC(50) values, respectively, with these cells.
Spectroscopic study of telluric acid and selenic acid in hydrogen fluoride and the hydrolysis of tellurium hexafluoride (1975)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSpectroscopic study of telluric acid and selenic acid in hydrogen fluoride and the hydrolysis of tellurium hexafluorideUri. Elgad and Henry. SeligCite this: Inorg. Chem. 1975, 14, 1, 140–145Publication Date (Print):January 1, 1975Publication History Published online1 May 2002Published inissue 1 January 1975https://pubs.acs.org/doi/10.1021/ic50143a031https://doi.org/10.1021/ic50143a031research-articleACS PublicationsRequest reuse permissionsArticle Views128Altmetric-Citations23LEARN 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
Regulation of human Δ-6 desaturase gene transcription: identification of a functional direct repeat-1 element (2003)

The rate-limiting step in 20:4(n-6) and 22:6(n-3) synthesis is the desaturation of 18:2(n-6) and 18:3(n-3) by Delta-6 desaturase. In this report, we demonstrate that n-6 and n-3 PUFAs suppressed the hepatic expression of rodent Delta-6 desaturase by inhibiting the rate of Delta-6 desaturase gene transcription. In contrast, consumption of the peroxisome proliferator-activated receptor (PPAR)alpha activator WY 14,643 significantly enhanced the transcription of hepatic Delta-6 desaturase by more than 500%. Transfection reporter assays with HepG2 cells revealed that the PUFA response region for the human Delta-6 desaturase gene involved the proximal promoter region of -283/+1 human Delta-6 desaturase gene, while the WY 14,643 response element (RE) was identified as an imperfect direct repeat (DR-1) located at -385/-373. The WY 14,643 induction of the human Delta-6 desaturase promoter activity was dependent upon the expression of PPARalpha. Electrophoretic mobility shift assays revealed that nuclear proteins extracted from HepG2 cells expressing PPARalpha specifically interacted with the -385/-373 DR-1 sequence of the human Delta-6 desaturase gene. The interaction was eliminated by the unlabeled PPARalpha RE of the rat acyl-CoA oxidase gene, and the protein-DNA complex was super-shifted by treatment with anti-PPARalpha. The -385/-373 sequence also interacted with a mixture of in vitro translated PPARalpha-retinoic acid receptor X (RXR)alpha, but by themselves neither PPARalpha nor RXRalpha could bind to the Delta-6 desaturase DR-1. These data indicate that the 5'-flanking region of the human Delta-6 desaturase gene contains a DR-1 that functions in the regulation of human Delta-6 desaturase gene transcription, and thereby plays a role in the synthesis of 20- and 22-carbon polyenoic fatty acids.
Alzheimer Disease Pathogenesis: Insights From Molecular and Cellular Biology Studies of Oligomeric Aβ and Tau Species (2019)

Alzheimer disease (AD) represents an oncoming epidemic that without an effective treatment promises to exact extraordinary human and financial burdens. Studies of pathogenesis are essential for defining targets for discovering disease-modifying treatments. Past studies of AD neuropathology provided valuable, albeit limited, insights. Nevertheless, building on these findings, recent studies have provided an increasingly rich harvest of genetic, molecular and cellular data that are creating unprecedented opportunities to both understand and treat AD. Among the most significant are those documenting the presence within the AD brain of toxic oligomeric species of Aβ and tau. Existing data support the view that such species can propagate and spread within neural circuits. To place these findings in context we first review the genetics and neuropathology of AD, including AD in Down syndrome (AD-DS). We detail studies that support the existence of toxic oligomeric species while noting the significant unanswered questions concerning their precise structures, the means by which they spread and undergo amplification and how they induce neuronal dysfunction and degeneration. We conclude by offering a speculative synthesis for how oligomers of Aβ and tau initiate and drive pathogenesis. While 100 years after Alzheimer's first report there is much still to learn about pathogenesis and the discovery of disease-modifying treatments, the application of new concepts and sophisticated new tools are poised to deliver important advances for combatting AD.
Development and testing of regenerable hot-coal-gas desulfurization sorbents (1981)

Investigations over several years at the Morgantown Energy Technology Center have been concerned with the development of a regenerable metal oxide desulfurization sorbent which would function on hot coal-derived fuel gas. In the latest phase of testing, a combination of zinc oxide with iron oxide as zinc ferrite has produced a sorbent which has demonstrated regenerability and capability of removing sulfur from simulated hot coal gas to a level of 1 to 10 ppM by volume. The principal finding at this stage of the project is that the compound zinc ferrite and also iron oxide containing some zinc ferrite have hydrogen sulfide absorption performances very similar to those of zinc oxide. Extruded sorbents made from these compounds have been demonstrated to perform with varying ability in the temperature range 800/sup 0/F (427/sup 0/C) to 1400/sup 0/F (760/sup 0/C) at a space velocity of 2000 hourly and a hydrogen sulfide concentration of 2.7 percent. They have also been shown to be regenerable with a 50/50 percent v/v steam-air mixture at 1000/sup 0/F (538/sup 0/C) and 600 hourly space velocity with no loss of absorptive power. Both zinc ferrite and zinc oxide appear to perform optimally in the middle of the temperature range, where absorption capacity is greatest. Surprisingly, the experimental results indicate no trend to a lower degree of hydrogen sulfide removal with rise in temperature. Zinc ferrite appears to be superior to zinc oxide in terms of its absorption capacity and resistance to sintering at higher temperatures.
Genetic effects of oxidative DNA damage: comparative mutagenesis of 7,8-dihydro-8-oxoguanine and 7,8-dihydro-8-oxoadenine in<i>Escherichia coli</i> (1992)

A single 7,8-dihydro-8-oxoguanine (G8-OXO; 8-hydroxyguanine) adduct in the lacZ alpha gene of bacteriophage M13 DNA induces a targeted G-->T transversion after replication in Escherichia coli (Biochemistry, 29, 7024-7031 (1990)). This mutation is thought to be due to the facile formation during DNA synthesis of a G8-OXO.base pair, where G8-OXO is in the syn conformation about the deoxyglycosyl bond. A related modified purine, 7,8-dihydro-8-oxoadenine (A8-OXO; 8-hydroxyadenine), is an abundant product found in irradiated and oxidized DNAs. Similar to G8-OXO, as a mononucleoside A8-OXO assumes the syn conformation. This work has assessed the relative mutagenicities of A8-OXO and G8-OXO in the same experimental system. A deoxypentanucleotide containing A8-OXO [d(GCT-A8-OXOG)] was synthesized. After 5'-phosphorylation with [gamma-32P] ATP, the oligomer was ligated into a duplex M13mp19-derived genome at a unique NheI restriction site. Genomes containing either A8-OXO (at position 6275, [+] strand) or G8-OXO (position 6276) were denatured with heat and introduced into E.coli DL7 cells. Analysis of phage DNA from mutant plaques obtained by plating immediately after transformation (infective centers assay) revealed that G8-OXO induced G-->T transversions at an apparent frequency of approximately 0.3%. The frequency and spectrum of mutations observed in DNA sequences derived from 172 mutant plaques arising from the A8-OXO-modified DNA were almost indistiguishable from those generated from transfection of an adenine-containing control genome. We conclude that A8-OXO is at least an order of magnitude less mutagenic than G8-OXO in E.coli cells with normal DNA repair capabilities.
Determinants of RNA-Dependent RNA Polymerase (In)fidelity Revealed by Kinetic Analysis of the Polymerase Encoded by a Foot-and-Mouth Disease Virus Mutant with Reduced Sensitivity to Ribavirin (2008)

A mutant poliovirus (PV) encoding a change in its polymerase (3Dpol) at a site remote from the catalytic center (G64S) confers reduced sensitivity to ribavirin and forms a restricted quasispecies, because G64S 3Dpol is a high-fidelity enzyme. A foot-and-mouth disease virus (FMDV) mutant that encodes a change in the polymerase catalytic site (M296I) exhibits reduced sensitivity to ribavirin without restricting the viral quasispecies. In order to resolve this apparent paradox, we have established a minimal kinetic mechanism for nucleotide addition by wild-type (WT) FMDV 3Dpol that permits a direct comparison to PV 3Dpol as well as to FMDV 3Dpol derivatives. Rate constants for correct nucleotide addition were on par with those of PV 3Dpol, but apparent binding constants for correct nucleotides were higher than those observed for PV 3Dpol. The A-to-G transition frequency was calculated to be 1/20,000, which is quite similar to that calculated for PV 3Dpol. The analysis of FMDV M296I 3Dpol revealed a decrease in the calculated ribavirin incorporation frequency (1/8,000) relative to that (1/4,000) observed for the WT enzyme. Unexpectedly, the A-to-G transition frequency was higher (1/8,000) than that observed for the WT enzyme. Therefore, FMDV selected a polymerase that increases the frequency of the misincorporation of natural nucleotides while specifically decreasing the frequency of the incorporation of ribavirin nucleotide. These studies provide a mechanistic framework for understanding FMDV 3Dpol structure-function relationships, provide the first direct analysis of the fidelity of FMDV 3Dpol in vitro, identify the beta9-alpha11 loop as a (in)fidelity determinant, and demonstrate that not all ribavirin-resistant mutants will encode high-fidelity polymerases.