gebhart/patrepeval huggingface dataset:
Organotypic liver culture models: Meeting current challenges in toxicity testing (2012)

Prediction of chemical-induced hepatotoxicity in humans from in vitro data continues to be a significant challenge for the pharmaceutical and chemical industries. Generally, conventional in vitro hepatic model systems (i.e. 2-D static monocultures of primary or immortalized hepatocytes) are limited by their inability to maintain histotypic and phenotypic characteristics over time in culture, including stable expression of clearance and bioactivation pathways, as well as complex adaptive responses to chemical exposure. These systems are less than ideal for longer-term toxicity evaluations and elucidation of key cellular and molecular events involved in primary and secondary adaptation to chemical exposure, or for identification of important mediators of inflammation, proliferation and apoptosis. Progress in implementing a more effective strategy for in vitro-in vivo extrapolation and human risk assessment depends on significant advances in tissue culture technology and increasing their level of biological complexity. This article describes the current and ongoing need for more relevant, organotypic in vitro surrogate systems of human liver and recent efforts to recreate the multicellular architecture and hemodynamic properties of the liver using novel culture platforms. As these systems become more widely used for chemical and drug toxicity testing, there will be a corresponding need to establish standardized testing conditions, endpoint analyses and acceptance criteria. In the future, a balanced approach between sample throughput and biological relevance should provide better in vitro tools that are complementary with animal testing and assist in conducting more predictive human risk assessment.
In vitro effect on Cryptosporidium parvum of short-term exposure to cathelicidin peptides (2003)

Two laboratory methods, a cell culture system and double fluorogenic staining, were used to study the viability and infective ability of Cryptosporidium parvum sporozoites and oocysts after short-term exposure to four cathelicidin peptides. The compounds, SMAP-29, BMAP-28, PG-1 and Bac7(1-35), exerted a strong cytotoxic effect on sporozoites, but did not affect the viability and function of oocysts consistently. Overall, in the sporozoite series, a percentage of the viable population decreased rapidly to less than detectable levels after 15 and 60 min exposure to the peptides at concentrations of 100 and 10 micro g/mL, respectively. In the oocyst series, no compound produced complete inhibition of parasite growth: 60-85% of the oocyst population was viable after 180 min exposure at 100 micro g/mL. SMAP-29 exerted the highest activity against both sporozoites and oocysts.
ChemInform Abstract: 2‐Oxazolidinones for Regioselective Protection of β‐Amino Alcohols in the Synthesis of 2‐Amino‐1‐aryl‐3‐fluoro‐1‐propanols. (1987)

Abstract The synthesis of the fluoro analogue (VIII) of thiamphenicol (IX) is reported.
Condensation Approach to Aliphatic Oligourea Foldamers: Helices with N‐(Pyrrolidin‐2‐ylmethyl)ureido Junctions (2011)

Caught in a fold: A simple and efficient coupling strategy to make aliphatic oligourea foldamers is reported. Crystal structures show that the pyrrolidine units (red; see picture) do not impair the 2.5-helical folding of the oligoureas. This modular strategy enables assembly of long helical segments containing non-adjacent pyrrolidine units as exemplified by the synthesis of a helix that is approximately 40 Å long.
Immune intervention with monoclonal antibodies targeting CD152 (CTLA-4) for autoimmune and malignant diseases. (2008)

CD152 or cytotoxic T lymphocyte antigen-4 (CTLA-4) is an essential receptor involved in the negative regulation of T cell activation. Because of its profound inhibitory role, CD152 has been considered a sound susceptible candidate in autoimmunity and a persuasive target for cancer immunotherapy for over a decade. However, the precise roles played by this molecule continue to emerge. In particular, recent evidence suggests that CD152 is also important in the homeostasis and function of a population of suppressive cells, termed regulatory T cells (Treg). In this review, we discuss the recent progress and main features of monoclonal antibodies (mAbs) targeting CD152 and examine how each mAb prepared to a distinct epitope may impact differently upon CD152 modulation depending on its demonstrated regulatory role acting as an agonist, antagonist, or inverse agonist.
High definition MAC: the compatible route to HDTV (1988)

The current discussion on standards for high definition television has concentrated on the studio standard to be used for picture generation. The situation is analyzed from the opposite end of the TV chain, considering the needs of the viewer. The latest developments in this respect within the Eureka Project EU-95 on high-definition television (HDTV) are highlighted. The HDTV display and two transmission coding schemes are discussed. The system selected for 1988 demonstration is described.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Lightpath (wavelength) routing in large WDM networks (1996)

We address the problem of efficient circuit switching in wide area optical networks. The solution provided is based on finding optimal routes for lightpaths and the new concept of semilightpaths. A lightpath is a fully optical transmission path, while a semilightpath is a transmission path constructed by chaining together several lightpaths, using wavelength conversion at their junctions. A fast and practical algorithm is presented to optimally route lightpaths and semilightpaths taking into account both the cost of using the wavelengths on links and the cost of wavelength conversion. We prove that the running time of the algorithm is the best possible in the wide class of algorithms allowing linear algebraic operations on weights. This class encompasses all known related practical methods. Additionally, our method works for any physical realization of wavelength conversion, independently whether it is done via optoelectronic conversion or in a fully optical way.
Microbiological Transformations. 47. A Step toward a Green Chemistry Preparation of Enantiopure (S)-2-, -3-, and -4-Pyridyloxirane via an Epoxide Hydrolase Catalyzed Kinetic Resolution (2000)

The biocatalyzed hydrolytic kinetic resolution of 2-, 3-, and 4-pyridyloxirane by the Aspergillus niger epoxide hydrolase (EH) has been explored. This was used to perform a gram scale preparation of these epoxides of (S) absolute configuration using a process performed at a concentration as high as 10 g/L (82 mM). All three epoxides have been obtained in a nearly enantiopure form (ee > 98%). Interestingly, it was shown that this biotransformation could be achieved using plain water instead of buffer solution, an important improvement as far as downstream processing of an eventual industrial process is concerned. Neither of these substrates could be obtained in reasonable enantiomeric purity and yield using the nowadays most efficient metal-based catalysts.
Physiological response of central metabolism in Escherichia coli to deletion of pyruvate oxidase and introduction of heterologous pyruvate carboxylase (2005)

We studied the physiological response of Escherichia coli central metabolism to the expression of heterologous pyruvate carboxylase (PYC) in the presence and absence of pyruvate oxidase (POX). These studies were complemented with expression analysis of central and intermediary metabolic genes and conventional in vitro enzyme assays to evaluate glucose metabolism at steady-state growth conditions (chemostats). The absence of POX activity reduced nongrowth-related energy metabolism (maintenance coefficient) and increased the maximum specific rate of oxygen consumption. The presence of PYC activity (i.e., with POX activity) increased the biomass yield coefficient and reduced the maximum specific oxygen consumption rate compared to the wildtype. The presence of PYC in a poxB mutant resulted in a 42% lower maintenance coefficient and a 42% greater biomass yield compared to the wildtype. Providing E. coli with PYC or removing POX increased the threshold specific growth rate at which acetate accumulation began, with an 80% reduction in acetate accumulation observed at a specific growth rate of 0.4 h-1 in the poxB-pyc+ strain. Gene expression analysis suggests utilization of energetically less favorable glucose metabolism via glucokinase and the Entner-Doudoroff pathway in the absence of functional POX, while the upregulation of the phosphotransferase glucose uptake system and several amino acid biosynthetic pathways occurs in the presence of PYC. The physiological and expression changes resulting from these genetic perturbations demonstrate the importance of the pyruvate node in respiration and its impact on acetate overflow during aerobic growth.
Random multiple scattering of ultrasound. II. Is time reversal a self-averaging process? (2001)

This is the second article in a series of two dealing with the statistical moments of ultrasonic waves transmitted through a disordered medium with resonant multiple scattering. Second-order moments in time and space are considered here. An ultrasonic pulsed wave is transmitted from a point source to a 128-element receiving array through two-dimensional samples with various thicknesses. The samples consist of random collections of parallel steel rods immersed in water. The scattered waves are recorded, time reversed, and sent back into the medium. The time-reversed waves are converging back to their source and the quality of spatial and temporal focusing on the source is related to the second-order moments of the scattered wave (correlation) in time and in space. Experimental results show that it is possible to obtain a robust estimation on a single realization of disorder, taking advantage of the wide frequency bandwidth. The spatial resolution of the system is only limited by the correlation length of the scattered field, and no longer by the array aperture. As the sample thickness is increased, the quality of focusing saturates, which we believe is linked to the Thouless factor g. In the thickest sample, g approximately 30, which is still well above the localization threshold.
Stacked reconfigurable circular patch antenna for adaptive MIMO systems (2009)

In this paper we present a novel design of a reconfigurable circular patch antenna (RCPA) for multiple input multiple output (MIMO) communication systems. This antenna allows for high pattern diversity and exhibits good radiation efficiency in all of its configurations. The compact array is capable of dynamically changing the shape of its radiation pattern by selecting a pair of feed points connected to two stacked circular disks. Different electromagnetic modes are excited in the antenna structure to achieve pattern reconfigurability. The performance achievable with this antenna in MIMO systems is determined through channel measurements collected in an indoor environment. Results show a capacity improvement of 11% when using the proposed array at one end of a 2 times 2 MIMO system with respect to a system that employs non reconfigurable antennas.
Zum Stand der Dinge: Die Computerwelt und ihre wissenschaftliche Beobachtung (1990)

In der kurzen Zeit, die seit seiner Einführung vergangen ist, hat der Computer eine Überfülle von Kommentaren, Lobreden und Schmährufen erfahren. Das, was den Zeitgenossen der Erfindung des Buchdrucks widerfuhr, nämlich aufgrund einer allgemeinen Uninformiertheit den durch die neue Technik eingeleiteten Strukturwandel der Gesellschaft schlichtweg nicht wahrgenommen zu haben, sollte sich im Zeitalter der Verbreitung moderner elektronischer Medien nicht wiederholen.
ApoE-deficient mice develop lesions of all phases of atherosclerosis throughout the arterial tree. (1994)

Initial description of apolipoprotein (apo) E-deficient transgenic mice demonstrated the development of severe hypercholesterolemia due to probable delayed clearance of large atherogenic particles from the circulation. Examination of these mice demonstrated foam cell accumulation in the aortic root and pulmonary arteries by 10 weeks of age. In the present study, the animals were fed either chow or a high-fat, Western-type diet and examined at ages ranging from 6 to 40 weeks. Gross examination by dissection microscopy revealed a predilection for development of lesions in the aortic root, at the lesser curvature of the aortic arch, the principal branches of the aorta, and in the pulmonary and carotid arteries. Monocyte attachment to endothelial cells was observed by light and electron microscopic examination at 6 weeks, the earliest time point examined. Foam cell lesions developed as early as 8 weeks, and after 15 weeks advanced lesions (fibrous plaques) were observed. The latter consisted of a fibrous cap containing smooth muscle cells surrounded by connective tissue matrix that covered a necrotic core with numerous foamy macrophages. Mice fed the Western-type diet generally had more advanced lesions than those fed a chow diet. The apoE-deficient mouse contains the entire spectrum of lesions observed during atherogenesis and is the first mouse model to develop lesions similar to those in humans. This model should provide numerous opportunities to study the pathogenesis and therapy of atherosclerosis in a small, genetically defined animal.
Force–length characteristics of in vivo human skeletal muscle (2001)

In the present study, the in vivo force-length relations of the human soleus (SOL) and tibialis anterior (TA) muscles were estimated. Measurements were taken in six men at ankle angles from 30 degrees of dorsiflexion to 45 degrees of plantarflexion in steps of 15 degrees, and involved dynamometry, electrical stimulation, ultrasonography and magnetic resonance imaging (MRI). For each muscle and ankle angle studied the following three measurements were carried out: (1) dynamometry-based measurement of maximal voltage tetanic moment, (2) ultrasound-based measurement of pennation angle and fibre length and (3) MRI-based measurement of tendon moment arm length. Tendon forces were calculated dividing moments by moment arm lengths, and muscle forces were calculated dividing tendon forces by the cosine of pennation angles. In the transition from 30 degrees of dorsiflexion to 45 degrees of plantarflexion the SOL muscle fibre length decreased from 3.8 to 2.4 cm and its force decreased from 3330 to 290 N. Over the same range of ankle angles the TA muscle fibre length increased from 3.7 to 6 cm and its force increased from 157 to 644 N. Over the longest muscle fibre lengths reached the force of both muscles remained approximately constant. These results indicate that the intact human SOL and TA muscles operate in the ascending limb and plateau region of the force-length relationship. Similar conclusions were reached when calculating the theoretical operating range of the two muscle sarcomeres in the study.
Stochastic Thresholds (1986)

Thresholds have traditionally been represented by a single number; the optimal management of the patient depends on whether his probability of disease is above or below this number. The concept of a threshold as a single number, however, inadequately represents the treatment approach of a group of physicians who do not have all the same threshold or a single physician who is uncertain about the exact value of the threshold. An alternative to a single valued threshold is to consider the threshold as having a probability distribution: for every probability that the patient has the disease there is a probability that the threshold is exceeded. This "stochastic" threshold model contains information about the uncertainty of the threshold estimation. Stochastic thresholds can be useful for testing the sensitivity of a management decision to the patient's probability of disease. They can also be used for comparing the standards of practice of individual physicians or comparing the practice of an individual physician with that of a group.
Carbon nano-onions (multi-layer fullerenes): chemistry and applications (2014)

This review focuses on the development of multi-layer fullerenes, known as carbon nano-onions (CNOs). First, it briefly summarizes the most important synthetic pathways for their preparation and their properties and it gives the reader an update over new developments in the recent years. This is followed by a discussion of the published synthetic procedures for CNO functionalization, which are of major importance when elucidating future applications and addressing drawbacks for possible applications, such as poor solubility in common solvents. Finally, it gives an overview over the fields of application, in which CNO materials were successfully implemented.
Overview of the Scalable Coherent Interface, IEEE STD 1596 (SCI) (2003)

The Scalable Coherent Interface (SCI) standard defines a new generation of interconnection that spans the full range from supercomputer memory 'bus' to campus-wide network. SCI provides bus-like services and a shared-memory software model while using an underlying packet protocol on many independent communication links. Initially these links are 1 GByte/s (wires) and 1 GBit/s (fiber), but the protocol scales well to future faster or lower-cost technologies. The interconnect may use switches, meshes, and rings. The SCI distributed-shared-memory model is simple and versatile, enabling a smooth integration of highly parallel multiprocessors, workstations, personal computers, input/output, networking, and data acquisition.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Eosinophils and Cancer (2014)

Eosinophils have long been known to infiltrate tumors, and in most cases, this is associated with an improved prognosis. However, the reasons behind this infiltration and the mechanism of action of the eosinophil have remained elusive. In this article, we explore the biology of eosinophils and examine their function in homeostasis and disease states, specifically focusing on what is currently known about the association of the eosinophil with cancer.
Inhibition of N-acetylglucosaminyl transfer enzymes: chemical-enzymic synthesis of new five-membered acetamido azasugars (1993)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInhibition of N-acetylglucosaminyl transfer enzymes: chemical-enzymic synthesis of new five-membered acetamido azasugarsYoshikazu Takaoka, Tetsuya Kajimoto, and Chi Huey WongCite this: J. Org. Chem. 1993, 58, 18, 4809–4812Publication Date (Print):August 1, 1993Publication History Published online1 May 2002Published inissue 1 August 1993https://pubs.acs.org/doi/10.1021/jo00070a013https://doi.org/10.1021/jo00070a013research-articleACS PublicationsRequest reuse permissionsArticle Views349Altmetric-Citations73LEARN 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-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts
Molecular Staging for Survival Prediction of Colorectal Cancer Patients (2005)

These data support further evaluation of molecular staging to discriminate good from poor prognosis patients, with the potential to direct adjuvant therapy.
Multichannel image deblurring of raw color components (2005)

This paper presents a novel multi-channel image restoration algorithm. The main idea is to develop practical approaches to reduce optical blur from noisy observations produced by the sensor of a camera phone. An iterative deconvolution is applied separately to each color channel directly on the raw data obtained from the camera sensor. We use a modified iterative Landweber algorithm combined with an adaptive denoising technique. The employed adaptive denoising is based on Local Polynomial Approximation (LPA) operating on data windows, which are selected by the rule of Intersection of Confidence Intervals (ICI). In order to avoid false coloring due to independent component filtering in RGB space, we have integrated a novel regularization mechanism that smoothly attenuates the high-pass filtering near saturated regions. Through simulations, it is shown that the proposed filtering is robust with respect to errors in point-spread function (PSF) and approximated noise models. Experimental results show that the proposed processing technique produces significant improvement in perceived image resolution.
Probing the Efficiency of Electron Transfer through Porphyrin-Based Molecular Wires (2007)

Electron transfer over long distances is important for many future applications in molecular electronics and solar energy harvesting. In these contexts, it is of great interest to find molecular systems that are able to efficiently mediate electrons in a controlled manner over nanometer distances, that is, structures that function as molecular wires. Here we investigate a series of butadiyne-linked porphyrin oligomers with ferrocene and fullerene (C60) terminals separated by one, two, or four porphyrin units (Pn, n = 1, 2, or 4). When the porphyrin oligomer bridges are photoexcited, long-range charge separated states are formed through a series of electron-transfer steps and the rates of photoinduced charge separation and charge recombination in these systems were elucidated using time-resolved absorption and emission measurements. The rates of long-range charge recombination, through these conjugated porphyrin oligomers, are remarkably fast (kCR2 = 15 - 1.3 x 108 s-1) and exhibit very weak distance dependence, particularly comparing the systems with n = 2 and n = 4. The observation that the porphyrin tetramer mediates fast long-range charge transfer, over 65 A, is significant for the application of these structures as molecular wires.