gebhart/patrepeval huggingface dataset:
Comparison of nonivamide and capsaicin with regard to their pharmacokinetics and effects on sensory neurons. (1984)

Nonanoyl vanillylamide (nonivamide NVA) was compared with trans-8-methyl-N-vanillyl-nonenamide (capsaicin, CAP) with regard to their pharmacokinetic properties, their potency in stimulating primary afferent neurons and depleting them of substance P and somatostatin in rats. Following the injection of 50 mg kg-1 the time course of the presence of NVA in brain and blood was similar to that of CAP. The concentration of NVA in brain was higher than in blood; the reverse was true for CAP. The ability of NVA and CAP to stimulate afferent neurons was measured by the reflex depressor response following i.v. injection and by the number of wiping movements following instillation of the substances into the eye. In both tests, the potency of NVA was about half of that of CAP. Treatment of newborn rats by s.c. injections of 50 mg kg-1 NVA or CAP seemed to cause a larger depletion of substance P and somatostatin in the sciatic nerve and the spinal cord than treatment of adult rats. Depletion by CAP was generally larger than that by NVA although depletion experiments are hardly suitable for quantification. The depletion of substance P by CAP and NVA could be correlated with the extent to which ocular chemosensitivity and neurogenic plasma extravasations were attenuated. The methods used are discussed in view of their possible use in screening further capsaicin analogues.
IIP2 Calibration Methods for Current Output Mixer In Direct-Conversion Receivers (2005)

In this paper, two different IIP2 calibration methods for Gilbert cell type mixers with current-mode output are presented. The first method controls the transconductance of the mixer input stage and the second method the LO signal, respectively. Both methods are also suitable for the resistively loaded Gilbert cell mixer, which has a voltage-mode output.
Meningococcal Genetic Variation Mechanisms Viewed through Comparative Analysis of Serogroup C Strain FAM18 (2007)

The bacterium Neisseria meningitidis is commonly found harmlessly colonising the mucosal surfaces of the human nasopharynx. Occasionally strains can invade host tissues causing septicaemia and meningitis, making the bacterium a major cause of morbidity and mortality in both the developed and developing world. The species is known to be diverse in many ways, as a product of its natural transformability and of a range of recombination and mutation-based systems. Previous work on pathogenic Neisseria has identified several mechanisms for the generation of diversity of surface structures, including phase variation based on slippage-like mechanisms and sequence conversion of expressed genes using information from silent loci. Comparison of the genome sequences of two N. meningitidis strains, serogroup B MC58 and serogroup A Z2491, suggested further mechanisms of variation, including C-terminal exchange in specific genes and enhanced localised recombination and variation related to repeat arrays. We have sequenced the genome of N. meningitidis strain FAM18, a representative of the ST-11/ET-37 complex, providing the first genome sequence for the disease-causing serogroup C meningococci; it has 1,976 predicted genes, of which 60 do not have orthologues in the previously sequenced serogroup A or B strains. Through genome comparison with Z2491 and MC58 we have further characterised specific mechanisms of genetic variation in N. meningitidis, describing specialised loci for generation of cell surface protein variants and measuring the association between noncoding repeat arrays and sequence variation in flanking genes. Here we provide a detailed view of novel genetic diversification mechanisms in N. meningitidis. Our analysis provides evidence for the hypothesis that the noncoding repeat arrays in neisserial genomes (neisserial intergenic mosaic elements) provide a crucial mechanism for the generation of surface antigen variants. Such variation will have an impact on the interaction with the host tissues, and understanding these mechanisms is important to aid our understanding of the intimate and complex relationship between the human nasopharynx and the meningococcus.
Sequential Self-Folding Structures by 3D Printed Digital Shape Memory Polymers (2015)

Folding is ubiquitous in nature with examples ranging from the formation of cellular components to winged insects. It finds technological applications including packaging of solar cells and space structures, deployable biomedical devices, and self-assembling robots and airbags. Here we demonstrate sequential self-folding structures realized by thermal activation of spatially-variable patterns that are 3D printed with digital shape memory polymers, which are digital materials with different shape memory behaviors. The time-dependent behavior of each polymer allows the temporal sequencing of activation when the structure is subjected to a uniform temperature. This is demonstrated via a series of 3D printed structures that respond rapidly to a thermal stimulus, and self-fold to specified shapes in controlled shape changing sequences. Measurements of the spatial and temporal nature of self-folding structures are in good agreement with the companion finite element simulations. A simplified reduced-order model is also developed to rapidly and accurately describe the self-folding physics. An important aspect of self-folding is the management of self-collisions, where different portions of the folding structure contact and then block further folding. A metric is developed to predict collisions and is used together with the reduced-order model to design self-folding structures that lock themselves into stable desired configurations.
Interaction of gelonin with zinc. (1987)

Gelonin, a plant protein which inactivates eukaryotic ribosomes, binds to zinc chelate Sepharose from which it is eluted with EDTA or histidine. After purification by metal chelate affinity chromatography, gelonin maintains the associated zinc-dependent proteinase activity previously described. In equilibrium dialysis about 4 moles of zinc bind per mole of gelonin with a dissociation constant of 0.96 mM. Ca2+ behaves as a mixed competitive and non-competitive inhibitor of the binding of zinc with Ki = 29 mM.
Organizations for Standardization of Quantities and Units (1995)

Many international organizations have contributed to the development of the International System of Units (SI). The highest international authority on units is the General Conference on Weights and Measures (CGPM), which is an intergovernmental body. Legal aspects of units and metrology are dealt with by the International Organization of Legal Metrology (OIML), whereas scientific questions in this field are dealt with by scientific unions such as the International Union of Pure and Applied Physics (IUPAP), and the International Union of Pure and Applied Chemistry (IUPAC). Among their many tasks the international standards organizations, i.e. the International Organization for Standardization (ISO), and the International Electrotechnical Commission (IEC), implement the SI as adopted by the CGPM. They also standardize quantities, i.e. their definitions, names, and letter symbols. The main purpose of this article is to present these two organizations for standardization and to describe their role in the standardization of quantities and units.
Large‐Scale Purification and Some Properties of Malate Synthase from Baker's Yeast (1981)

1. Malate synthase from baker's yeast (5 kg) was purified 400--500-fold to homogeneity. About 50--200 mg homogeneous enzyme were obtained within a week in a yield of 30% with reference to the total activity in cell-free crude extracts. The enzyme, pI = 7.5, was pure as judged from ultracentrifugal and gel electrophoretic studies. 2. Sedimentation and diffusion coefficients were determined: S 0 20,w = 8.26 +/- 0.05 S, D 0 20,w = 4.5 +/- 0.1 X 10(-7) cm2 s-1. The molecular weight of the synthase was found to be 175 000 +/- 10 000 and 180 000 +/- 10 000 by sedimentation/diffusion and by high-speed sedimentation equilibrium respectively. It was concluded from these and other results that malate synthase has a molecular mass of 180 000 +/- 10 000. 3. The synthase on sodium dodecylsulfate gel electrophoresis was dissociated to yield a single specimen of Mr about 66 000. The result indicates a composition of the native enzyme from three subunits of identical or nearly identical mass. 4. The binding of acetyl-coenzyme A to the synthase is independent of Mg2+ but that of glyoxylate is strictly dependent on the presence of Mg2+. Kinetic studies indicate that the malate synthase reaction follows a sequential random mechanism. 5. The intermolecular isotopic effect, kH:k2H = 1.4, was determined with acetyl-coenzyme A and [2H3]acetyl-coenzyme A under several different experimental conditions and was shown to reflect different maximal velocities of the two substrates. An enzymic procedure for the preparation of doubly labelled [3H, 14C]acetyl-coenzyme A is also presented.
Increased Plasma Levels of Insulin-Like Growth Factor 2 and Insulin-Like Growth Factor Binding Protein 3 Are Associated with Endometrial Cancer Risk (2004)

Circulating insulin-like growth factors (IGFs) and their binding proteins have been associated with increased risk of breast, prostate, colon, and lung cancer. To examine the association of IGFs and endometrial cancer risk, we measured the plasma levels of IGF-1, IGF-2, and IGF binding protein 3 (IGFBP-3) by ELISA in 80 women with endometrial cancer and 80 age-matched control subjects with no history of cancer. Mean plasma levels of IGF-2 were significantly higher in women with cancer versus controls (670 ng/ml versus 380 ng/ml, P < 0.001). In contrast, significantly lower mean plasma levels of IGF-1 (155 mg/ml versus 185 ng/ml, P < 0.01) and IGFBP-3 (1703 ng/ml versus 2170 ng/ml, P < 0.001) were observed among cases compared to the control group. Women in the highest quartile of IGF-2 were found to have 9.67 (95% confidence interval 3.29-28.43) times the risk of endometrial cancer than women in the lowest quartiles. Women in the highest quartile of IGFBP-3 were associated with a significantly decreased risk for developing endometrial cancer (odds ratio = 0.23, 95% confidence interval 0.09-0.60). These data suggest that increased plasma levels of IGF-2 and decreased levels of IGFBP-3 are associated with an increased risk of endometrial cancer. Further validation of these results is needed to determine the potential usefulness of risk assessment.
Altered fruit ripening and leaf senescence in tomatoes expressing an antisense ethylene‐forming enzyme transgene (1993)

Summary Tomato plants in which the synthesis of ethylene‐forming enzyme (EFE) had been inhibited by an anti‐sense gene were used to study the role of ethylene in fruit ripening at the biochemical and molecular level. A reduction in total lycopene accumulation was observed in EFE‐antisense fruit ripened both on and off the plant. The rate of over‐ripening and fruit spoilage was also reduced in the EFE‐antisense fruit. The degree of inhibition of ripening was shown to be dependent upon the stage of development at which the fruit were detached from the plant. The effects on ripening in EFE‐antisense fruit were much more pronounced when fruit were detached from the vine before the onset of colour change, and were associated with changes in the level of accumulation of mRNAs homologous to a number of previously characterized ripening‐related cDNAs. The retarded ripening of detached EFE‐antisense fruit could be partially restored by ethylene treatment. In addition to changes observed in ripening fruit, a temporal delay in the onset of foliar senescence was observed in EFE‐antisense plants, indicating that the physiological effects of the EFE‐antisense gene, and the associated reduction in ethylene evolution, are not confined specifically to fruit ripening.
Transmission of Signals from the T Lymphocyte Antigen Receptor to the Genes Responsible for Cell Proliferation and Immune Function: The Missing Link (1990)

Exhausted CD8 T (Tex) cells are a distinct cell lineage that arise during chronic infections and cancers in animal models and humans. Tex cells are characterized by progressive loss of effector functions, high and sustained inhibitory receptor expression, ...Read More
Membrane Trafficking Regulates the Activity of the Human Dopamine Transporter (1999)

The trafficking of synaptic proteins is unquestionably a major determinant of the properties of synaptic transmission. Here, we present a detailed analysis of the downregulation and intracellular trafficking of the cocaine- and amphetamine-sensitive dopamine transporter (DAT), a presynaptic plasma membrane protein responsible for the regulation of extracellular DA concentrations. Using PC12 cells stably transfected with human DAT cDNA, we observe that phorbol ester activation of protein kinase C (PKC) results in decreased transporter capacity and a parallel decrease in the amount of DAT on the cell surface that is attributable to intracellular transporter sequestration. After internalization, DAT diverges to the recycling, as opposed to the degradative, arm of the endocytic pathway. This study demonstrates, for the first time, DAT endocytosis, establishes the pathways through which DAT traffics both at steady state and in response to PKC activation, and suggests that DAT recycling is likely to occur.
The mechanism of proton exclusion in aquaporin channels (2004)

The mechanism of proton exclusion in aquaporin channels is elucidated through free energy calculations of the pathway of proton transport. The second generation multistate empirical valence bond (MS-EVB2) model was applied to simulate the interaction of an excess proton with the channel environment. Jarzynski's equality was employed for rapid convergence of the free energy profile. A barrier sufficiently high to block proton transport is located near the channel center at the NPA motif-a site involved in bi-orientational ordering of the embedded water-wire in absence of the excess proton. A second and lower barrier is observed at the selectivity filter near the periplasmic outlet where the channel is narrowest. This secondary barrier may be essential in filtering other large solutes and cations.
Morphology of femtosecond laser-induced structural changes in bulk transparent materials (2004)

Using optical and electron microscopy, we analyze the energy and focusing angle dependence of structural changes induced in bulk glass by tightly focused femtosecond laser pulses. We observe a transition from small density variations in the material to void formation with increasing laser energy. At energies close to the threshold for producing a structural change, the shape of the structurally changed region is determined by the focal volume of the objective used to focus the femtosecond pulse, while at higher energies, the structural change takes on a conical shape. From these morphological observations, we infer the role of various mechanisms for structural change.
Gut Microbiota-Derived Short-Chain Fatty Acids, T Cells, and Inflammation (2014)

T cells are central players in the regulation of adaptive immunity and immune tolerance. In the periphery, T cell differentiation for maturation and effector function is regulated by a number of factors. Various factors such as antigens, co-stimulation signals, and cytokines regulate T cell differentiation into functionally specialized effector and regulatory T cells. Other factors such as nutrients, micronutrients, nuclear hormones and microbial products provide important environmental cues for T cell differentiation. A mounting body of evidence indicates that the microbial metabolites short-chain fatty acids (SCFAs) have profound effects on T cells and directly and indirectly regulate their differentiation. We review the current status of our understanding of SCFA functions in regulation of peripheral T cell activity and discuss their impact on tissue inflammation.
Applying cartoon animation techniques to graphical user interfaces (2001)

If judiciously applied, animation techniques can enhance the look and feel of computer applications that present a graphical human interface. Such techniques can smooth the rough edges and abrupt transitions common in many current graphical interfaces, and strengthen the illusion of direct manipulation that many interfaces strive to present. To date, few applications include such animation techniques. One possible reason is that animated interfaces are difficult to implement: they are difficult to design, place great burdens on programmers, and demand high-performance from underlying graphics systems.This article describes how direct manipulation human computer interfaces can be augmented with techniques borrowed from cartoon animators. In particular, we wish to improve the visual feedback of a direct manipulation interface by smoothing the changes of an interface, giving manipulated objects a feeling of substance and providing cues that anticipate the result of a manipulation. Our approach is to add support for animation techniques such as object distortion and keyframe interpolation, and to provide prepackaged animation effects such as animated widgets for common user interface interactions.To determine if these tools and techniques are practical and effective, we built a prototype direct manipulation drawing editor with an animated interface and used the prototype editor to carry out a set of human factors experiments. The experiments show that the techniques are practical even on standard workstation hardware, and that the effects can indeed enhance direct manipulation interfaces.
SPR-MS in functional proteomics (2005)

The mapping of protein networks and the establishment of the functional relationships between expressed proteins and their effects on cellular processes represents a great challenge for functional or interaction proteomics. The combination of surface plasmon resonance (SPR)-based technology with mass spectrometry (MS) has created a unique analytical tool for functional proteomics investigations. Proteins are affinity purified, quantified and characterised in terms of their interactions, while the mass spectrometer identifies and structurally characterises the biomolecules. Recent developments have led to a closer integration of these key technologies, providing a combined approach which enables identification of proteins selected on the basis of their functional binding criteria. In addition to a historical overview of this field, some recent detailed examples of combined SPR-MS approaches will be reviewed in a number of key application areas, including ligand fishing, peptide sequence and post-translational modification analysis by SPR-MS/MS and enzyme inhibitor screening.
High-Resolution CT Imaging of Carotid Artery Atherosclerotic Plaques (2008)

The composition of carotid atherosclerotic plaques determined by CTA reflects plaque composition defined by histologic examination.
Designing cell-permeant phosphopeptides to modulate intracellular signaling pathways (2001)

A central theme in intracellular signaling is the regulatable interaction of proteins via the binding of specialized domains on one protein to short linear sequences on other molecules. The capability of these short sequences to mediate the required specificity and affinity for signal transduction allows for the rational design of peptide-based modulators of specific protein-protein interactions. Such inhibitors are valuable tools for elucidating the role of these interactions in cellular physiology and in targeting such interactions for potential therapeutic intervention. This approach is exemplified by the study of the role of phosphorylation of specific sites on signaling proteins. However, the difficulty of introducing large hydrophilic molecules such as phosphopeptides into cells has been a major drawback in this area. This review describes the application of recently developed cell-permeant peptide vectors in the introduction of biologically active peptides into cells, with particular emphasis on the antennapedia/penetratin, TAT, and signal-peptide based sequences. In addition, the modification of such peptides to increase uptake efficiency and affinity for their targets is discussed. Finally, the use of cell-permeant phosphopeptides to both inhibit and stimulate intracellular signaling mechanisms is described, by reference to the PLCgamma, Grb2, and PI-3 kinase pathways.
Endocytosis and intracellular processing of transferrin and colloidal gold-transferrin in rat reticulocytes: demonstration of a pathway for receptor shedding. (1984)

Endocytosis and intracellular processing of transferrin (Tf) and Tf receptors were examined in rat reticulocytes. Subcellular fractionation revealed that Tf enters a non-lysosomal endocytic compartment with a density between those of plasma membrane and lysosomes. After 20 min of uptake at (37 degrees C) 35 to 40% of cell-associated Tf was contained in this intermediate-density compartment. To test the fidelity of colloidal gold-Tf (AuTf) as a probe for Tf processing, reticulocytes were fractionated after uptake of 131I-Tf and 125I-AuTf. The subcellular distributions of the two ligands were indistinguishable by this method, a result suggesting that AuTf is processed similarly to Tf. Electron microscopy revealed that AuTf entered multivesicular endosomes (MVEs) as well as various small vesicles and tubular structures. In addition MVE exocytosis was observed with discharge of inclusion vesicles and associated AuTf. AuTf was bound to the outside of these vesicles both before and after exocytosis. These data suggest that Tf receptors are shed from developing reticulocytes by incorporation into the limiting membrane of inclusion vesicles, followed by discharge of these vesicles by MVE exocytosis. As further evidence of this process, we isolated inclusion vesicles after their discharge and found them to contain Tf receptors. Moreover, the rate of Tf receptor shedding by inclusion vesicle discharge matches Tf receptor loss rates closely enough to suggest that this is the primary path of receptor loss during reticulocyte development.
Is there a common mechanism linking muscle wasting in various disease types? (2007)

These results suggest a common mechanism leading to muscle atrophy, which has important implications in the clinical treatment of wasting diseases.
Direct Semiconductor Bonded 5J Cell for Space and Terrestrial Applications (2013)

Spectrolab has demonstrated a 2.2/1.7/1.4/1.05/0.73 eV 5J cell with an efficiency of 37.8% under 1 sun AM1.5G spectrum and 35.1% efficiency for 1 sun AM0. The top three junctions and bottom two junctions were grown on GaAs and InP substrates, respectively, by metal organic vapor phase epitaxy. The GaAs- and InP-based cells were then direct bonded to create a low-resistance, high-transmissive interface. Both the space and terrestrial cells have high 1 sun V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">oc</sub> between 4.75 and 4.78 V. Initial tests of the terrestrial cells at concentration are promising with efficiencies increasing up to 10× concentration to a maximum value close to 41%.