gebhart/patrepeval huggingface dataset:
Hyperenteroglucagonaemia and small intestinal mucosal growth after colonic perfusion of glucose in rats. (1985)

Beside intraluminal factors, humoral agents play an important role in intestinal adaptation. Enteroglucagon, the mucosal concentration of which is maximal in the terminal ileum and colon, is the strongest candidate for the role of small intestinal mucosal growth factor. The present experiment was designed to study the role of colonic enteroglucagon in stimulating mucosal growth in rats with a normal small intestine. After eight days of glucose large bowel perfusion, enteroglucagon plasma concentrations were 120.7 +/- SEM 9.2 pmol/l, versus 60.1 +/- 6.8 in mannitol perfused control rats (p less than 0.001). Gastrin, cholecystokinin, neurotensin, pancreatic glucagon, and insulin plasma concentrations were unchanged. Crypt cell proliferation, measured by the vincristine metaphase arrest technique, increased significantly in the small intestine of glucose perfused animals (p less than 0.005-0.001) in comparison with the controls. This resulted in a greater mucosal mass in both proximal and distal small bowel: mucosal wet weight, DNA, protein and alpha D-glucosidase per unit length intestine were all significantly higher (p less than 0.05-0.001) than in mannitol perfused rats. Our data, therefore, support the hypothesis that enteroglucagon is an enterotrophic factor and stress the possible role of the colon in the regulation of small bowel trophicity.
Unconventional secretion of Acb1 is mediated by autophagosomes (2010)

Starving Dictyostelium discoideum cells secrete AcbA, an acyl coenzyme A-binding protein (ACBP) that lacks a conventional signal sequence for entering the endoplasmic reticulum (ER). Secretion of AcbA in D. discoideum requires the Golgi-associated protein GRASP. In this study, we report that starvation-induced secretion of Acb1, the Saccharomyces cerevisiae ACBP orthologue, also requires GRASP (Grh1). This highlights the conserved function of GRASP in unconventional secretion. Although genes required for ER to Golgi or Golgi to cell surface transport are not required for Acb1 secretion in yeast, this process involves autophagy genes and the plasma membrane t-SNARE, Sso1. Inhibiting transport to vacuoles does not affect Acb1 secretion. In sum, our experiments reveal a unique secretory pathway where autophagosomes containing Acb1 evade fusion with the vacuole to prevent cargo degradation. We propose that these autophagosome intermediates fuse with recycling endosomes instead to form multivesicular body carriers that then fuse with the plasma membrane to release cargo.
Phosphonates as analogues of natural phosphates (1977)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhosphonates as analogues of natural phosphatesRobert. EngelCite this: Chem. Rev. 1977, 77, 3, 349–367Publication Date (Print):June 1, 1977Publication History Published online1 May 2002Published inissue 1 June 1977https://pubs.acs.org/doi/10.1021/cr60307a003https://doi.org/10.1021/cr60307a003research-articleACS PublicationsRequest reuse permissionsArticle Views2750Altmetric-Citations680LEARN 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
CathCam Guide Wire-Directed Colonoscopy: First Pilot Study in Patients with a Previous Incomplete Colonoscopy (2006)

A combined approach, consisting of guide wire insertion via a partially introduced colonoscope followed by CathCam or colonoscope insertion into the caecum was successful in over 90 % of patients with previous failure of complete colonoscopy. Further improvements may make this system suitable for use as a standard diagnostic colonoscope, either as a single unit (CathCam plus guide wire) or using the guide wire alone with a standard colonoscope in difficult cases.
Multispot, multianalyte, immunoassay. (1990)

Consideration of the basic principles of immunoassay design reveals that highly sensitive assays can, in principle, be developed using amounts of "sensor" antibody far smaller than are currently conventional in this field. Furthermore, when using such amounts, the fractional occupancy of antibody binding sites by analyte is independent of both sample volume and antibody concentration. Labelling of both the sensor-antibody and a developing antibody (designed to recognize either occupied or unoccupied sensor-antibody binding sites) permits the development of "ratiometric" immunoassays relying on measurement of the ratio of signals emitted by the two labelled antibodies. Furthermore, the sensor-antibody can be located within a "microspot" a few microns 2 in area. By labelling both sensor and developing antibodies with fluorescent labels, and scanning the microspot using a highly focussed laser beam, microspot immunoassays at least comparable in sensitivity with conventional "macroscopic" immunoassays are made possible. This in turn permits the development of immunoassay "arrays" capable in principle of measuring very large numbers of different substances within small samples (such as a drop of blood). The general principles and theory underlying these concepts are discussed, and preliminary experimental data using currently available instrumentation reported.
Emerging drugs for idiopathic pulmonary fibrosis (2011)

The treatment of IPF represents one of the greatest challenges confronting respiratory medicine and, currently, there is no effective therapeutic option for IPF. Perhaps some of the drugs that are under evaluation in clinical trials will slow the decline of the pulmonary function tests or hopefully stabilize some patients. Nonetheless, it appears clear that new therapeutic approaches are urgently needed.
A three-hybrid system to detect RNA-protein interactions in vivo. (1996)

RNA-protein interactions are pivotal in fundamental cellular processes such as translation, mRNA processing, early development, and infection by RNA viruses. However, in spite of the central importance of these interactions, few approaches are available to analyze them rapidly in vivo. We describe a yeast genetic method to detect and analyze RNA-protein interactions in which the binding of a bifunctional RNA to each of two hybrid proteins activates transcription of a reporter gene in vivo. We demonstrate that this three-hybrid system enables the rapid, phenotypic detection of specific RNA-protein interactions. As examples, we use the binding of the iron regulatory protein 1 (IRP1) to the iron response element (IRE), and of HIV trans-activator protein (Tat) to the HIV trans-activation response element (TAR) RNA sequence. The three-hybrid assay we describe relies only on the physical properties of the RNA and protein, and not on their natural biological activities; as a result, it may have broad application in the identification of RNA-binding proteins and RNAs, as well as in the detailed analysis of their interactions.
The Effects of Data and Graph Type on Concepts and Visualizations of Variability (2010)

Recognizing and interpreting variability in data lies at the heart of statistical reasoning. Since graphical displays should facilitate communication about data, statistical literacy should include an understanding of how variability in data can be gleaned from a graph. This paper identifies several types of graphs that students typically encounter—histograms, distribution bar graphs, and value bar charts. These graphs all share the superficial similarity of employing bars, and yet the methods to perceive variability in the data differ dramatically. We provide comparisons within each graph type for the purpose of developing insight into what variability means and how it is evident within the data's associated graph. We introduce graphical aids to visualize variability for histograms and value bar charts, which could easily be tied to numerical estimates of variability.
Evaluating and optimizing autonomous text classification systems (1995)

Text retrieval systems typically produce a ranking of documents and let a user decide how far down that ranking to go. In contrast, programs that filter text streams, software that categorizes documents, agents which alert users, and many other IR systems must make decisions without human input or supervision. It is important to define what constitutes good effectiveness for these autonomous systems, tune the systems to achieve the highest possible effectiveness, and estimate how the effectiveness changes as new data is processed. We show how to do this for binary text classification systems, emphasizing that different goals for the system lead to different optimal behaviors. Optimizing and estimating effectiveness is greatly aided if classifiers that explicitly estimate the probability of class membership are used. 1
Prenyltransferase: determination of the binding mechanism and individual kinetic constants for farnesylpyrophosphate synthetase by rapid quench and isotope partitioning experiments (1981)

The 1'-4 condensation reaction catalyzed by farnesylpyrophosphate synthetase was examined by using rapid quench and isotope partitioning experiments. E.Mg2+-isopentyl-PP (PP = pyrophosphate) is not catalytically competent, as evidenced by failure to trap the complex with Mg2+-geranyl-PP at concentrations as high as 3.2 mM. In contrast, the concentration of Mg2+-isopentenyl-PP required for one-half maximal trapping (K 1/2) of E.Mg2+-geranyl-PP is 1.4 muM. The results strongly support an ordered mechanism for the 1'-4 condensation reaction, with addition of the allylic substrate before Mg2+-isopentenyl-PP. At short reaction times, a burst phase corresponding to accumulation of Mg2+-farnesyl-PP on the surface of the enzyme, followed by a slower, steady-state release of products, is observed. Evaluation of individual kinetic constants for the reaction indicates that the rates for addition of Mg2+-geranyl-PP to the enzyme (k1 = 4.9 X 10(6) M-1 s-1) and addition of Mg2+-isopentenyl-PP to E.Mg2+-geranyl-PP (k3 = 2 X 10(6) m-1 s-1) are below the diffusion-controlled limit. The rate-limiting step at steady state is isomerization of E.Mg2+-farnesyl-PP-Mg2+-PPi or release of products (k6 = 0.1 s-1). During the course of isotope partitioning experiments with E.Mg2+-geranyl-PP, a new dual isotope procedure was developed which minimizes difficulties encountered during workup. In addition, for enzymes such as farnesyl-PP synthetase that catalyze irreversible reactions, the dual isotope approach is both sensitive extremely easy to execute.
The mycobacteria: an introduction to nomenclature and pathogenesis (2001)

Tuberculosis, caused by Mycobacterium tuberculosis, and leprosy, caused by M. leprae, are diseases known since antiquity. In developing countries, tuberculosis is still the leading cause of mortality due to an infectious disease. Taxonomically, mycobacteria belong to the genus Mycobacterium, which is the single genus within the family of Mycobacteriaceae, in the order Actinomycetales. Actinomycetales include diverse micro-organisms, but mycobacteria and allied taxa are easily distinguished on the basis of the ability to synthesise mycolic acids. Mycobacterial species are traditionally differentiated on the basis of phenotypic characteristics, and the authors provide an updated list of the biochemical tests currently employed and the culture properties that help to discriminate among various species of mycobacteria. However, as the phenotypic characteristics do not allow precise identification of all species, recent molecular taxonomical approaches for mycobacterial classification and phylogeny are also described. Mycobacteria are also a leading cause of infection in various domesticated animals and wildlife. The authors briefly describe the mycobacteria involved in animal infections, the wildlife reservoirs and strategies to control bovine tuberculosis, and the use of molecular tools for diagnostics and epidemiology of mycobacterial infections in animals. The characteristic of intracellular parasitism is discussed, in addition to the fate of pathogenic mycobacteria that have the ability to grow inside phagosomes and phagolysosomes of infected host macrophages. The mycobacterial cell envelope, which is a complex tripartite structure containing a high proportion of lipids (approximately 30% to 40% of the total weight) could play a crucial role in the adaptation of mycobacteria to intracellular growth and survival, immune modulation and drug resistance.
Neuronal pathology in the nucleus basalis and associated cell groups in senile dementia of the Alzheimer's type (1985)

The loss of cortical cholinergic innervation in senile dementia of the Alzheimer's type (SDAT) is associated with cell loss in the nucleus basalis and related cell groups (magnocellular basal nucleus, MBN). We examined MBN in Nissl-, acetylcholinesterase- and thioflavin S-stained sections in two cases of SDAT and in four control brains. Using these sensitive methods, senile plaques were easily demonstrated in MBN, and most MBN neurons showed neurofibrillary degeneration as an early change. Cell loss appeared to be due to maturation of neurofibrillary tangles, displacing normal cellular contents. In contrast to theories that the cell loss in MBN represents retrograde degeneration due to axonal injury in the cerebral cortex, MBN neuronal perikarya may be involved by the same primary processes as cortical neurons.
Functional Properties of Motoneurons Derived from Mouse Embryonic Stem Cells (2004)

The capacity of embryonic stem (ES) cells to form functional motoneurons (MNs) and appropriate connections with muscle was investigated in vitro. ES cells were obtained from a transgenic mouse line in which the gene for enhanced green fluorescent protein (eGFP) is expressed under the control of the promotor of the MN specific homeobox gene Hb9. ES cells were exposed to retinoic acid (RA) and sonic hedgehog agonist (Hh-Ag1.3) to stimulate differentiation into MNs marked by expression of eGFP and the cholinergic transmitter synthetic enzyme choline acetyltransferase. Whole-cell patch-clamp recordings were made from eGFP-labeled cells to investigate the development of functional characteristics of MNs. In voltage-clamp mode, currents, including EPSCs, were recorded in response to exogenous applications of GABA, glycine, and glutamate. EGFP-labeled neurons also express voltage-activated ion channels including fast-inactivating Na(+) channels, delayed rectifier and I(A)-type K(+) channels, and Ca(2+) channels. Current-clamp recordings demonstrated that eGFP-positive neurons generate repetitive trains of action potentials and that l-type Ca(2+) channels mediate sustained depolarizations. When cocultured with a muscle cell line, clustering of acetylcholine receptors on muscle fibers adjacent to developing axons was seen. Intracellular recordings of muscle fibers adjacent to eGFP-positive axons revealed endplate potentials that increased in amplitude and frequency after glutamate application and were sensitive to TTX and curare. In summary, our findings demonstrate that MNs derived from ES cells develop appropriate transmitter receptors, intrinsic properties necessary for appropriate patterns of action potential firing and functional synapses with muscle fibers.
Deterin, a New Inhibitor of Apoptosis from Drosophila melanogaster (2000)

Deterin, a new apoptosis inhibitor from Drosophila melanogaster, possesses an unusual structure of only a single baculovirus inhibitor of apoptosis (IAP)-type repeat and no RING finger motif. The biochemical actions of deterin are demonstrated in SF9 and S2 cell transfection assays, in which the expressed protein acts in the cytoplasm to inhibit or deter cells from apoptosis otherwise induced by the caspase-dependent apoptosis activator reaper or by cytotoxicants. A loss of function phenotype for deterin of cell death was indicated by transfections with either a dominant negative deterin mutant or with inhibitory RNA (RNAi) for deterin. The dominant negative C-terminal fragment that antagonized antiapoptotic activity of deterin did not affect antiapoptotic activity of DIAP1 or p35. Both the baculovirus IAP-type repeat (BIR) domain and the alpha-helical C-terminal domain are necessary in both SF9 and S2 cells for deterin to manifest its activity to prevent cell death. The approximately 650-base deterin transcript is present in embryos, third instar larvae, and late stage nurse cells of adult females. The deterin transcript is distributed throughout early stage embryos, whereas in later stage embryos it becomes progressively restricted to the central nervous system and gonads. Whereas the nematode survivin-type IAP has thus far been implicated only as a mitotic regulator, Drosophila deterin constitutes the first invertebrate member of the survivin-type IAP group to exhibit apoptosis-inhibitory activity.
A smoothly constrained Kalman filter (1997)

This paper presents the Smoothly Constrained Kalman Filter (SCKF) for nonlinear constraints. A constraint is any relation that exists between the state variables. Constraints can be treated as perfect observations. But, linearization errors can prevent the estimate from converging to the true value. Therefore, the SCKF iteratively applies nonlinear constraints as nearly perfect observations, or, equivalently, weakened constraints. Integration of new measurements is interlaced with these iterations, which reduces linearization errors and, hence, improves convergence compared to other iterative methods. The weakening is achieved by artificially increasing the variance of the nonlinear constraint. The paper explains how to choose the weakening values, and when to start and stop the iterative application of the constraint.
Optical beam-shifter module with high extinction ratio for 1024-input-port optical-switching network (1993)

An optical beam shifter module consisting of liquid-crystal cells and a birefringent plate is investigated for a 1024-input-port switching network. High extinction ratio (&gt; 20 dB) and low insertion loss (0.5 dB) are achieved by optimal device design. Precise optical alignment is obtained without any adjustment mechanism by using assembly baseplate and an optical assembly bench.
Distortion-based crest factor reduction algorithms in multi-carrier transmission systems (2007)

Distortion-based crest factor reduction (CFR) algorithms were studied in orthogonal frequency division multiplexing (OFDM) and multiple-input multiple-output (MIMO) OFDM systems to reduce the nonlinear distortion and improve the power efficiency of the transmitter front-end. First, definitions of peak-to-average-power ratio (PAR) were clarified based on the power efficiency improvement consideration in the MIMO-OFDM systems. Next, error vector magnitude (EVM) was used as the in-band performance-evaluating metric. Statistical analysis of EVM was performed to provide concrete thresholds for the amount of allowable distortions from each source to meet EVM requirements in the standard. Furthermore, an effective CFR technique, constrained clipping, was proposed to drastically reduce the PAR while satisfying any given in-band EVM and out-of-band spectral mask constraints. Constrained clipping has low computational complexity and can be easily extended to the multiple-user OFDM environment. Finally, signal-to-noise-and-distortion ratio (SNDR) analysis for transceiver nonlinearities in the additive white Gaussian noise channel was investigated. An analytical solution was presented for maximizing the transceiver SNDR for any given set of nonlinear transmitter polynomial coefficients. Additionally, mutually inverse pair of transceiver nonlinearities was shown to be SNDR-optimal only in the noise-free case.
Cloned structural genes for the osmotically regulated binding‐protein‐dependent glycine betaine transport system (ProU) of Escherichia coli K‐12 (1988)

The proU locus of Escherichia coli encodes a high-affinity, binding-protein-dependent transport system (ProU) for the osmoprotectant glycine betaine. We cloned this locus into both low-copy-number lambda vectors and multicopy plasmids and demonstrated that these clones restore osmotically controlled synthesis of the periplasmic glycine betaine binding protein (GBBP) and the transport of glycine betaine in a delta (proU) strain. These clones allowed us to investigate the influence of osmolarity on ProU transport activity independent of the osmotically controlled expression of proU. ProU activity was strongly stimulated by a moderate increase in osmolarity and was partially inhibited by high osmolarity. This activity profile differs from the profile of the osmotically regulated proU expression. The proU locus is organized in an operon and the position of the structural gene (proV) for GBBP is defined using a minicell system. We determined that at least three proteins (in addition to GBBP) are encoded by the proU locus. We also investigated the permeation of glycine betaine across the outer membrane. At low substrate concentration (0.7 microM), permeation of glycine betaine was entirely dependent on the OmpF and OmpC porins.