gebhart/patrepeval huggingface dataset:
Low-Coordinate Carbene Complexes of Nickel(0) and Platinum(0) (1994)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLow-Coordinate Carbene Complexes of Nickel(0) and Platinum(0)Anthony J. Arduengo III, Siegfried F. Gamper, Joseph C. Calabrese, and Fredric DavidsonCite this: J. Am. Chem. Soc. 1994, 116, 10, 4391–4394Publication Date (Print):May 1, 1994Publication History Published online1 May 2002Published inissue 1 May 1994https://pubs.acs.org/doi/10.1021/ja00089a029https://doi.org/10.1021/ja00089a029research-articleACS PublicationsRequest reuse permissionsArticle Views3549Altmetric-Citations245LEARN 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 (2)»Supporting Information Supporting Information Get e-Alerts
Regulation of Dictyostelium morphogenesis by cAMP-dependent protein kinase (1993)

During formation of the Dictyostelium slug extracellular cAMP signals direct the differentiation of prespore cells and DIF, a chlorinated hexaphenone, induces the differentiation of prestalk cells. At culmination the slug transforms into a fruiting body, composed of a stalk supporting a ball of spores. A dominant inhibitor of cAMP-dependent protein kinase (PKA) expressed under the control of a prestalk-specific promoter blocks the differentiation of prestalk cells into stalk cells. Analysis of a gene specifically expressed in stalk cells suggests that PKA acts to remove a repressor that prevents the premature induction of stalk cell differentiation by DIF during slug migration. PKA is also necessary for the morphogenetic movement of prestalk cells at culmination. Expression of the PKA inhibitor under control of a prespore-specific promoter blocks the accumulation of prespore mRNA sequences and prevents terminal spore cell differentiation. Thus PKA is essential for progression along both pathways of terminal differentiation but with different mechanisms of action. On the stalk cell pathway it acts to regulate the action of DIF while on the spore cell pathway PKA itself seems to act as the inducer of spore cell maturation. Ammonia, the extracellular signal which regulates the entry into culmination, acts by controlling the intracellular concentration of cAMP and thus exerts its effects via PKA. The fact that PKA is necessary for both prespore and spore gene expression leads us to postulate the existence of a signalling mechanism which converts the progressive rise in cAMP concentration during development into discrete, PKA-regulated gene activation events.
Electrophysiologic Principles of Radiofrequency Lesion Making (1976)

Understanding of the electrophysiologic principles of radiofrequency lesion making is necessary to ensure reliable results in surgical procedures using this technique. A radiofrequency lesion is produced by tissue electrocoagulation. Its method of formation and factors affecting heat generation and loss are discussed. Guidelines for making radiofrequency lesions, based on electrophysiologic principles are outlined.
Targeted cancer diagnosis with radiolabeled endostatin (2005)

Nuclear imaging is used for non-invasive detection, staging and therapeutic monitoring of tumors through the use of radiolabeled probes. Generally, these probes are used for applications in which they provide passive, non-specific information about the target. Therefore, there is a significant need for actively-targeted radioactive probes to provide functional information about the site of interest. This study examined endostatin, an endogenous inhibitor of tumor angiogenesis, which has affinity for tumor vasculature. The major objective of this study was to develop radiolabeled analogues of endostatin through novel chemical and radiochemical syntheses, and to determine their usefulness for tumor imaging using in vitro and in vivo models of vascular, mammary and prostate tumor cells. I hypothesize that this binding will allow for a non-invasive approach to detection of tumor angiogenesis, and such detection can be used for therapeutic monitoring to determine the efficacy of anti-angiogenic therapy. The data showed that endostatin could be successfully conjugated to the bifunctional chelator ethylenedicysteine (EC), and radiolabeled with technetium-99m and gallium-68, providing a unique opportunity to use a single precursor for both nuclear imaging modalities: 99mTc for single photon emission computed tomography and 68Ga for positron emission tomography, respectively. Both radiolabeled analogues showed increased binding as a function of time in human umbilical vein endothelial cells and mammary and prostate tumor cells. Binding could be blocked in a dose-dependent manner by unlabeled endostatin implying the presence of endostatin receptors on both vascular and tumor cells. Animal biodistribution studies demonstrated that both analogues were stable in vivo, showed typical reticuloendothelial and renal excretion and produced favorable absorbed organ doses for application in humans. The imaging data provide evidence that the compounds quantitate tumor volumes with clinically-useful tumor-to-nontumor ratios, and can be used for treatment follow-up to depict changes occurring at the vascular and cellular levels. Two novel endostatin analogues were developed and demonstrated interaction with vascular and tumor cells. Both can be incorporated into existing nuclear imaging platforms allowing for potential wide-spread clinical benefit as well as serving as a diagnostic tool for elucidation of the mechanism of action of endostatin.
Purified Escherichia coli recA protein catalyzes homologous pairing of superhelical DNA and single-stranded fragments. (1979)

Purified Escherichia coli recA protein catalyzed ATP-dependent pairing of superhelical DNA and homologous single-stranded fragments. The product of the reaction: (i) was retained by nitrocellulose filters in 1.5 M NaCl/0.15 M Na citrate at pH 7, (ii) was dissociated at pH 12.3 but was not dissociated by heating at 55 degrees C for 4 min or by treatment with 0.2% sodium dodecyl sulfate and proteinase K, (iii) contained covalently closed circular double-stranded DNA (form I DNA), (iv) contained single-stranded fragments associated with replicative form (RF) DNA, and (v) contained a significant fraction of D-loops as judged by electron microscopy. Linear and nicked circular double-stranded DNA did not substitute well for superhelical DNA; intact circular single-stranded DNA did not substitute well for single-stranded fragments. Homologous combinations of single-stranded fragments and superhelical DNA from phages phiX174 and fd reacted, whereas heterologous combinations did not. The reaction required high concentrations of protein and MgCl2. The ATPase activity of purified recA protein was more than 98% dependent on the addition of single-stranded DNA. In 1 mM MgCl2, the ability of superhelical DNA to support the ATPase activity was two-thirds as good as that of single-stranded DNA.
Characterization of a novel mouse recombinant processing α-mannosidase (1994)

In previous work (Herscovics et al., J. Biol. Chem., 269, 9864-9871), a novel mouse alpha-mannosidase cDNA was isolated by homology, taking advantage of identical regions between the amino acid sequences of the yeast and rabbit liver processing alpha 1,2-mannosidases of different specificities to design degenerate oligonucleotides for reverse transcription/polymerase chain reaction. The cDNA isolated from a mouse 3T3 cDNA library encodes a 73 kDa type II membrane protein with a cytoplasmic region of approximately 35 amino acids and a large C-terminal region that contains a consensus Ca(2+)-binding sequence. To study the properties of this enzyme, the C-terminal part lacking the transmembrane region (beginning at either amino acid 106 or 171) was transiently expressed in COS cells as a secreted protein A fusion protein, and the enzymatic properties of the fusion protein bound to IgG-Sepharose were investigated. The enzyme is an alpha 1,2-mannosidase that trims Man9GlcNAc to Man5 GlcNAc (where Man is mannose and GlcNAc is N-acetyl glucosamine). The activity requires divalent cations since it is greatly inhibited by ethylene diamine tetraacetic acid (EDTA). Although Ca2+ is the most effective, the enzyme may also use Mg2+, Mn2+ or Co2+, but not Zn2+, which is inhibitory. The enzyme is inhibited by 1-deoxymannojirimycin, but not by swainsonine. We propose that this novel alpha 1,2-mannosidase cDNA encodes mouse Golgi alpha-mannosidase IB.
Prevention of neonatal group B streptococcal infections: advances in maternal vaccine development. (1992)

The development of a vaccine for prevention of neonatal group B streptococcal sepsis is an attainable goal. Further study of the immunogenic properties of bacterial-cell-wall polysaccharides and their conjugates, C proteins, and the potential universal antigen is required.
Factors Influencing the Accuracy of Age Estimates of Unfamiliar Faces (1995)

Factors affecting the accuracy with which adults could assess the age of unfamiliar male faces aged between 5 and 70 years were examined. In the first experiment twenty-five 'young' adult subjects, aged 16-25, and twenty-five 'old' adults, aged 51-60, were used. Each subject saw five versions of three different faces: these consisted of an original version of each face and four manipulated versions of it. The manipulations consisted of mirror reversal, pseudo-cardioidal strain, thresholding, and elimination of all but the internal features of the face. The second experiment was similar except that a between-subjects design was used: each subject saw three faces for each age category of target face, but was exposed to only a single type of manipulation (plus a set of 'original' faces which were identical for all groups, so that the comparability of the different groups in age estimation could be checked). Results from both experiments were similar. Age estimates for unmanipulated 'original' faces were highly accurate, although subjects were most accurate with target faces that were within their own age range. Results for the manipulated faces implied that the importance of cardioidal strain as a necessary and sufficient cue to age may have been overestimated in previous reports: subjects' age estimates were accurate when cardioidal strain was absent from the stimulus, and poor when cardioidal strain was the only cue available.
Effect of Vagal Nerve Electrostimulation on the Power Spectrum of Heart Rate Variability in Man (1992)

The power spectrum of heart rate variability contains low frequency (LF = 0.08-0.12 Hz) and high frequency (HF = 0.18-0.30 Hz) components said to represent neurocardiac rhythms. To verify whether such a relationship exists we report a unique study where the heart rate autospectrum was determined in a 28-year-old epileptic male patient with an implanted vagal electrical stimulator. The stimulator was activated at 20 Hz, 300 microseconds pulse, and 1.25 V. Continuous ECG and respiratory waveform records were obtained over 45 minutes every 8 hours (7-8 AM; 3-4 PM; 11-12 PM) with the stimulator ON, then 24 hours OFF and then 24 hours ON again. The overall LF:HF peak ratio increased from 0.64 to 1.99 (P less than 0.001) after the stimulator was turned OFF. There was a dramatic increase in the LF peak power (greater than 60%) and a corresponding decrease in the HF peak power (greater than 65%) when the stimulator was turned OFF. These values were reversed when the stimulator was turned ON again. In the early morning and late evening hours, there was a significant rightward shift in the LF peak power frequency (average 0.057 to 0.075 Hz) whenever the stimulator was ON. Otherwise, there were no significant circadian variations in any of the autospectral components. The results demonstrate an unequivocal relationship between selective vagal nerve electrostimulation and alterations in the heart rate autospectrum.
Clustering of death receptors in lipid rafts initiates neutrophil spontaneous apoptosis (2004)

Neutrophils die by apoptosis spontaneously within 12-24 h of their release from the bone marrow. The mechanism regulating entry of neutrophils into apoptosis at the end of their life-span is currently under debate. Our data suggest that neutrophil apoptosis involves a novel mechanism of caspase 8 activation that is indirectly regulated by accumulation of reactive oxygen species. We detected early activation of caspase 8 upstream of caspase 3 activation, suggesting death receptor signalling. The CD95 DISC (death-inducing signalling complex) was detected in neutrophils, but blocking antibodies to death receptors did not inhibit apoptosis, suggesting a novel mechanism for caspase 8 activation. Death receptor clustering in ceramide-rich lipid rafts is thought to be an early event in their signalling, so we investigated the role of ceramide generated by ASM (acid sphingomyelinase) in neutrophil apoptosis. Ceramide was generated early in neutrophil apoptosis, and ASM activity was required for neutrophil apoptosis. Moreover, neutrophil apoptosis was significantly delayed in ASM(-/-) mice compared with their wild-type littermates. CD95 DISC components were present in lipid rafts in neutrophils, and were progressively clustered in cultured neutrophils. Generation of ceramide was blocked by desferrioxamine, suggesting that hydroxyl radicals are important for the activation of ASM. This observation was in line with our earlier observation of a precipitous drop in reduced glutathione in the aging neutrophil.
SUV: standard uptake or silly useless value? (1995)

Quantification has always held a pervasive allure for nuclear medicine. There is a sense that anything that can be quantified should be. Once we have the numbers in hand, there is a mysterious tendency to accord them special value. Why this should be the case is unclear. Perhaps it is because of the functional nature of nuclear medicine studies, which seem as if they should be quantified. Perhaps it is because it is so easy to extract numbers from our studies. Whatever the cause, the phenomenon has been particularly strong in PET, in which we hear at every turn that PET is {open_quotes}quantitative.{close_quotes} DiChiro and Brooks commented on this phenomenon years ago, noting that, in many applications, subjective interpretation of PET images is actually superior to the use of quantitative data. Undaunted, however, the field has continued to lean heavily toward numbers as the final arbiter of correctness. 15 refs., 2 tabs.
Molecular control of ionic conduction in polymer nanopores (2009)

Polymeric nanopores show unique transport properties and have attracted a great deal of scientific interest as a test system to study ionic and molecular transport at the nanoscale. By means of all-atom molecular dynamics, we simulated the ion dynamics inside polymeric polyethylene terephthalate nanopores. For this purpose, we established a protocol to assemble atomic models of polymeric material into which we sculpted a nanopore model with the key features of experimental devices, namely a conical geometry and a negative surface charge density. Molecular dynamics simulations of ion currents through the pore show that the protonation state of the carboxyl group of exposed residues have a considerable effect on ion selectivity, by affecting ionic densities and electrostatic potentials inside the nanopores. The role of high concentrations of Ca2+ ions was investigated in detail.
Apoptosis in Caspase-inhibited Neurons (2001)

Our data suggest that Bcl-2-dependent and caspase-mediated death programs account only partially for neurodegenerative changes in injured neurons. Blockage of the caspase execution machinery may only temporarily rescue damaged neurons and classical apoptotic features can still appear in caspase-inhibited neurons.
Cloning and expression of the streptococcal C5a peptidase gene in Escherichia coli: linkage to the type 12 M protein gene (1989)

A genomic library of Streptococcus pyogenes CS24 DNA was constructed by cloning streptococcal DNA partially digested with Sau3A into the lambda replacement vector EMBL3. The expression of streptococcal C5a peptidase (SCP) was analyzed by radioimmunoassay with hyperimmune rabbit serum. Two clones, lambda 4.1 and lambda 4.2, were found to express the desired antigen, and various DNA fragments from the hybrid bacteriophage lambda 4.1 were subcloned into the plasmid vector pUC9 in Escherichia coli. One of the recombinant plasmids, designated pTT1, contained a 5.8-kilobase (kb) streptococcal DNA insert. Analysis of total cellular protein from this E. coli clone by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western (immuno-) blotting identified a 140,000-Mr protein, similar in size to the native protein purified from S. pyogenes. Cloned SCP was functionally active, as shown by its ability to inhibit C5a-mediated chemotaxis. By deletion analysis with both restriction endonucleases and BAL 31 nuclease, the SCP gene was localized to a 4.3-kb segment of DNA. Southern hybridization experiments showed that the type 12 M protein-coding sequence is also present in the hybrid phage lambda 4.1, at approximately 2 kb upstream of the SCP structural gene. Western blot analysis indicated that the cloned streptococcal DNA in lambda 4.1 directed the expression of both SCP and M12 protein.
Structural Insight into Pre-B Cell Receptor Function (2007)

The pre-B cell receptor (pre-BCR) serves as a checkpoint in B cell development. In the 2.7 angstrom structure of a human pre-BCR Fab-like fragment, consisting of an antibody heavy chain (HC) paired with the surrogate light chain, the "unique regions" of VpreB and lambda5 replace the complementarity-determining region 3 (CDR3) loop of an antibody light chain and appear to "probe" the HC CDR3, potentially influencing the selection of the antibody repertoire. Biochemical analysis indicates that the pre-BCR is impaired in its ability to recognize antigen, which, together with electron microscopic visualization of a pre-BCR dimer, suggests ligand-independent oligomerization as the likely signaling mechanism.
An Efficient SOFC Based on Samaria-Doped Ceria (SDC) Electrolyte (2012)

Doped ceria has been widely studied as electrolyte materials for intermediate temperature solid oxide fuel cells (IT-SOFCs). While high peak power densities have been reported, the electronic conductivity of doped ceria under fuel cell operating conditions reduces the open circuit voltage (OCV) and hence energy efficiency, more so with thinner electrolyte membrane at higher operating temperatures. Here we report a new cell structure: a thin SDC electrolyte membrane supported by a composite anode consisting of a mixed-ion conductor BaZr0.1Ce0.7Y0.1Yb0.1O3−δ (BZCYYb) and NiO. The inter-diffusion between BZCYYb and SDC during co-firing results in a thin layer of doped barium cerate and zirconate at the interface, which suppresses the electronic conduction of SDC and enhances the OCV and cell performance. The new cell structure also shows excellent stability when wet hydrogen or methane was used as fuel at 750°C.
CC family chemokines directly regulate myoblast responses to skeletal muscle injury (2008)

Chemokines have been implicated in the promotion of leucocyte trafficking to diseased muscle. The purpose of this study was to determine whether a subset of inflammatory chemokines are able to directly drive myoblast proliferation, an essential early component of muscle regeneration, in a manner which is entirely independent of leucocytes. Cultured myoblasts (C2C12) were exposed to monocyte chemoattractant protein-1 (MCP-1; CCL2), macrophage inflammatory protein-1alpha (MIP-1alpha; CCL3) or MIP-1beta (CCL4). All chemokines induced phosphorylation of extracellular signal-regulated kinase (ERK)1/2 mitogen-activated protein kinase (MAPK) and greatly increased myoblast proliferative responses. Chemokine-induced myoblast proliferation was abolished by pertussis toxin and the MEK1/2 inhibitor U0126, implicating both Galphai-coupled receptors and ERK1/2-dependent signalling. Myoblasts expressed receptors for all of the chemokines tested, and mitogenic responses were specifically inhibited by antibodies directed against CC family chemokine receptors 2 and 5 (CCR2 and CCR5). Within an in vitro myogenic wound healing assay devoid of leucocytes, all chemokines significantly accelerated the time course of myoblast wound closure after mechanical injury. Injections of MCP-1 into cardiotoxin-injured skeletal muscles in vivo also suppressed expression of the differentiation marker myogenin, consistent with a mitogenic effect. Taken together, our results indicate that CC chemokines have potent and direct effects on myoblast behaviour, thus indicating a novel role in muscle repair beyond leucocyte chemoattraction. Therefore, interventions aimed at modulating the balance between myoblast and leucocyte effects of CC chemokines in injured muscle could represent a novel strategy for the treatment of destructive muscle pathologies.
Natriuretic Peptides in Cardiovascular Disease (1997)

It is now well established that the heart and vascular endothelium are endocrine glands that synthesize and release natriuretic and vasoactive peptides. Specifically, the cardiac myocyte produces atrial and brain natriuretic peptides (ANP and BNP), whereas endothelial cells produce C-type natriuretic peptide (CNP). All three peptides share structural similarities, but are genetically distinct and have different roles in cardiovascular, renal, and endocrine regulation under physiological and pathophysiological conditions. Studies support the concept that the natriuretic peptides play a homeostatic role to maintain sodium excretion, promote vasodilatation, inhibit hypertrophic responses, and oppose the synthesis and actions of cardiovascular peptides, such as angiotensin II (ANG II) and endothelin (ET-1). Although a number of pathophysiologic states are characterized by involvement of the natriuretic peptide system, congestive heart failure (CHF) emerges as the paradigm in which the natriuretic peptides are activated to their greatest magnitude in nature. This has provided significant insight into the pathophysiology of this endocrine system. After reviewing the physiologic role of this system in cardiorenal homeostasis, this chapter will focus on the pathophysiology of the natriuretic peptides in CHF and explore potential therapeutic and diagnostic implications.
Listen to the brain: a Biological perspective On musical emotions (2001)

Abstract The functioning of the brain is fascinating. It fascinates for the obvious reason that the brain is the commander of all our actions, thoughts, and motivations. By studying its functioning, the hope is to obtain crucial information about the biological determinants of human cognition and emotion. Neuropsychology is the discipline concerned with these questions. As its name indicates, neuropsychology aims to relate neural mechanisms to mental functions. It is an old discipline, dating back to the discovery that speech was related to the functioning of a small region of the left brain by Broca in 1861. Following this discovery, the neural correlates of musical abilities were similarly scrutinized (for a recent review, see Marin &amp; Perry 1999). Although the neuropsychological approach to music is a century old, progress has been slow. term.