gebhart/patrepeval huggingface dataset:
Differentiation of human pluripotent stem cells to retinal pigmented epithelium in defined conditions using purified extracellular matrix proteins (2012)

A potential application of human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) is the generation of retinal pigmented epithelium (RPE) to treat age-related macular degeneration (AMD), a common but incurable retinal disease. RPE cells derived from hESCs (hESC-RPEs) and iPSCs (iPSC-RPEs) express essential RPE markers and can rescue visual function in animal models. However, standard differentiation protocols yield RPE cells at low frequency, especially from iPSC lines, and the common use of Matrigel and xenogeneic feeder cells is not compatible with clinical applications. The extracellular matrix (ECM) can affect differentiation, and therefore changes in ECM composition may improve the frequency of stem cell-RPE differentiation. We selected several purified ECM proteins and substrates, based on the in vivo RPE ECM environment, and tested their ability to support iPSC-RPE differentiation and maintenance. iPSCs differentiated on nearly all tested substrates developed pigmented regions, with Matrigel and mouse laminin-111 supporting the highest pigmentation frequencies. Although iPSC-RPEs cultured on the majority of the tested substrates expressed key RPE genes, only six substrates supported development of confluent monolayers with normal RPE morphology, including Matrigel and mouse laminin-111. iPSCs differentiated on mouse laminin-111 produced iPSC-RPEs expressing RPE proteins, and hESCs differentiated on mouse laminin-111 resulted in high yields of functional hESC-RPEs. This identification of key ECM proteins may assist with future scaffold designs and provide peptide sequences for use in synthetic, xeno-free, GMP-compliant generation of RPE from human pluripotent stem cells relevant to clinical translation.
Lipopolysaccharides of Campylobacter jejuni serotype O:19: Structures of O antigen chains from the serostrain and two bacterial isolates from patients with the Guillain-Barre syndrome (1994)

An O antigenic polysaccharide was liberated from the lipopolysaccharide of high M(r) from Campylobacter jejuni serotype O:19 by acetic acid hydrolysis of the ketosidic linkage to lipid A. The structure of the polysaccharide was established in several one- and two-dimensional 1H and 13C NMR experiments, fast atom bombardment mass spectrometry and methylation linkage analysis of the permethylated glycan and its degradation products. It is concluded that the glycan is a derivative of hyaluronic acid in which the beta-D-glucuronic acid residues in the alternating sequence [-4)-beta-D-GlcA-(1-->3)-beta-D-GlcNAc-(1]n are present as amides of 2-amino-2-deoxyglycerol. Parallel experiments were performed on O antigens liberated from lipopolysaccharides of high M(r) from bacterial isolates that had been obtained from two patients who subsequently developed the Guillain-Barré syndrome. Within the limits of structural analysis by NMR spectroscopy and methylation linkage analysis, both these O antigens were identical to that from the serostrain.
METABOLISM AND CYTOTOXICITY OF AFLATOXIN B 1 IN CYTOCHROME P-450-EXPRESSING HUMAN LUNG CELLS (2002)

The mycotoxin aflatoxin B(1) (AFB(1)) is a hepatocarcinogen in many animal models and probably a human carcinogen. Besides being a dietary carcinogen, AFB(1) has been detected in dusts generated in the processing and transportation of AFB(1)-contaminated products. Inhalation of grain dusts contaminated with AFB(1) may be a risk factor in human lung cancer. Aflatoxin B(1) requires cytochrome P-450 (CYP)-mediated activation to form cytotoxic and DNA-reactive intermediates, and this activation in human liver is mediated by the CYP 1A2 and 3A4 isoforms. Which isoforms are important in AFB(1) activation in human lung is not well understood. To investigate whether these CYPs can activate AFB(1) at low, environmentally relevant concentrations in human lung cells, SV40 immortalized human bronchial epithelial cells (BEAS-2B) that were transfected with cDNA for CYPs 3A4 (B3A4) or 1A2 (B-CMV1A2) were used. B-CMV1A2 cultured in 15 nM AFB(1) produced the AFB(1)-glutathione conjugate (AFB(1)-GSH) and aflatoxin M(1) (AFM(1)), while B3A4 cells produced only aflatoxin Q(1) (AFQ(1)) at 0.15 microM AFB(1). Nontransfected BEAS-2B cells produced no metabolites, even at 1.5 mM AFB(1). Microsomes prepared from B-CMV1A2 and B3A4 cells activated AFB(1) to AFB(1) 8,9-epoxide (AFBO), while those from BEAS-2B cells did not produce AFBO. Cytosol from all three cell types was ineffective at glutathione S-transferase (GST)-mediated trapping of enzymatically generated AFB(1) 8,9-epoxide. B-CMV1A2 cells were 100-fold more sensitive to AFB(1) compared to B3A4 cells, and were 6000-fold more sensitive than control BEAS-2B cells. Western immunoblots confirmed that only B-CMV1A2 cells expressed CYP 1A2 protein, while CYP 3A4 was only in B3A4 cells. B-CMV1A2 cells were the most sensitive to AFB(1), followed by B3A4 cells. CYP 3A4, which has been predicted to activate AFB(1) primarily at higher AFB(1) concentrations, was also responsible for significant AFB(1) toxicity at low concentrations. These data indicate that human lung cells expressing these CYP isoforms are capable of activating AFB(1), even at environmentally relevant concentrations.
Electroluminescence and semiconductor lasers (1966)

The various types of electroluminescence are discussed, with particular reference to the luminescence efficiency, and the materials in which electroluminescence has been observed are listed, Semiconductor lasers operating with electroluminescent, cathodoluminescent, or photoluminescent excitation, and some of the pertinent materials and operating parameters, are reviewed. All known semiconductor lasers are listed. Such devices are useful for a variety of applications, particularly if emission in the infrared region and operation at low temperatures is feasible. On the other hand, highly efficient visible electroluminescence or coherent emission has not been observed from any semiconductor at room temperature to date.
A pilot study of intralymphatic interleukin-2. II. Clinical and biological effects. (1990)

Interleukin-2 (recombinant methionyl human interleukin-2 alanine 125; IL-2) was administered intralymphatically to 12 patients with advanced cancer in a phase I trial. Doses were administered once a week for 6 weeks in a dosage escalation schedule; patients were entered in four groups at successively higher starting dosages. Toxicity occurred in a profile similar to that seen with intravenous IL-2. The maximum tolerated dose with this route/schedule was 275,000 units/kg, a figure not higher than expected with intravenous administration. T1/2 alpha was prolonged to 54 min from the 13 min figure we obtained with IL-2 given intravenously. Granulocytosis and eosinophilia were seen, along with lymphocytosis following initial lymphopenia. Anti-IL-2 antibodies were seen in 42% of patients (compared to 16% with this agent given intravenously), suggesting increased immunogenicity of this route/schedule. No clinical response was achieved. Immunologic effects will be reported separately but are summarized.
Interactions between epinephrine, ascending vagal fibers, and central noradrenergic systems in modulating memory for emotionally arousing events (2012)

It is well-established that exposure to emotionally laden events initiates secretion of the arousal-related hormone epinephrine in the periphery. These neuroendocrine changes and the subsequent increase in peripheral physiological output play an integral role in modulating brain systems involved in memory formation. The impermeability of the blood brain barrier to epinephrine represents an important obstacle in understanding how peripheral hormones initiate neurochemical changes in the brain that lead to effective memory formation. This obstacle necessitated the identity of a putative pathway capable of conveying physiological changes produced by epinephrine to limbic structures that incorporate arousal and affect related information into memory. A major theme of the proposed studies is that ascending fibers of the vagus nerve may represent such a mechanism. This hypothesis was tested by evaluating the contribution of ascending vagal fibers in modulating memory for responses learned under behavioral conditions that produce emotional arousal by manipulating appetitive stimuli. A combination of electrophysiological recording of vagal afferent fibers and in vivo microdialysis was employed in a second study to simultaneously assess how elevations in peripheral levels of epinephrine affect vagal nerve discharge and the subsequent potentiation of norepinephrine release in the basolateral amygdala. The final study used double immunohistochemistry labeling of c-fos and dopamine beta hydroxylase (DBH), the enzyme for norepinephrine synthesis to determine if epinephrine administration alone or stimulation of the vagus nerve at an intensity identical to that which improved memory in Experiment 1 produces similar patterns of neuronal activity in brain areas involved in processing memory for emotional events. Findings emerging from this collection of studies establish the importance of ascending fibers of the vagus nerve as an essential pathway for conveying the peripheral consequences of physiological arousal on brain systems that encode new information into memory storage.
Iida and Ishihara Reply: (2004)

A Reply to the Comment by T. Iida and H. Ishihara.Received 5 November 2003DOI:https://doi.org/10.1103/PhysRevLett.92.089702©2004 American Physical Society
A Natural Intergenotypic Recombinant of Hepatitis C Virus Identified in St. Petersburg (2002)

Hepatitis C virus (HCV) evolution is thought to proceed by mutations within the six genotypes. Here, we report on a viable spontaneous HCV recombinant and we show that recombination may play a role in the evolution of this virus. Previously, 149 HCV strains from St. Petersburg had been subtyped by limited sequencing within the NS5B region. In the present study, the core regions of 41 of these strains were sequenced to investigate the concordance of HCV genotyping for these two genomic regions. Two phylogenetically related HCV strains were found to belong to different subtypes, 2k and 1b, according to sequence analysis of the 5' untranslated region (5'UTR)-core and the NS5B regions, respectively. By sequencing of the E2-p7-NS2 region, the crossover point was mapped within the NS2 region, probably between positions 3175 and 3176 (according to the numbering system for strain pj6CF). Sequencing of the 5'UTR-core regions of four other HCV strains, phylogenetically related to the above-mentioned two strains (based on analysis within the NS5B region), revealed that these four strains were also recombinants. Since a nonrecombinant 2k strain was found in St. Petersburg, the recombination may have taken place there around a decade ago. Since the frequency of this recombinant is now high enough to allow the detection of the recombinant in a fraction of the city's population, it seems to be actively spreading there. The reported recombinant is tentatively designated RF1-2k/1b, in agreement with the nomenclature used for HIV recombinants. Recombination between HCV genotypes must now be considered in the classification, laboratory diagnosis, and treatment of HCV infection.
Organic light-emitting device with an ordered monolayer of silica microspheres as a scattering medium (2000)

Periodic dielectric structures, consisting of hexagonally closed-packed arrays of silica microspheres with the diameter of 550 nm, were incorporated into organic light-emitting devices with a conventional two-layer structure made with vacuum-sublimation. The arrays acted as a two-dimensional diffraction lattice which behaved as a light scattering medium for the light propagated in waveguiding modes within the device. Strongly scattered light emission through the front surface of the devices was observed. An increase in the device coupling-out factor for electroluminescent efficiency by using the scattering structure is demonstrated.
Beschreibung chemischer Strukturen (1991)

Wenn wir Angaben zur Struktur einer chemischen Verbindung machen wollen, so müssen wir die räumliche Verteilung der Atome in geeigneter Weise, beschreiben. Dies kann zunächst einmal mit Hilfe der chemischen Nomenklatur geschehen, welche zumindest für Moleküle einigermaßen ausgefeilt ist. Für Festkörperstrukturen gibt es keine systematische Nomenklatur, mit der sich strukturelle Gegebenheiten erfassen lassen. Man behilft sich mit der Angabe von Strukturtypen, etwa in folgender Art: „Magnesium-fluorid kristallisiert im Rutil-Typ“, womit für MgF2 eine Verteilung von Mg- und F-Atomen zum Ausdruck gebracht wird, die derjenigen von Ti-und O-Atomen im Rutil entspricht. Jeder Strukturtyp wird durch einen willkürlich gewählten Vertreter bezeichnet. Wie man strukturelle Gegebenheiten in Formeln zum Ausdruck bringen kann, wird in Abschnitt 2.1 erläutert.
Progressive Renal Disease: Fibroblasts, Extracellular Matrix, and Integrins (1999)

Progressive renal disease is characterized by expansion of the tubulo-interstitium and accumulation of extracellular matrix within this tissue compartment. Interstitial fibroblasts are the primary producers of the interstitial matrix, and in the evolution of tubulo-interstitial fibrosis these cells undergo changes, namely increased proliferation, differentiation to myofibroblasts, and altered extracellular matrix metabolism, all of which, in other cell types, have been shown to be regulated by the major family of extracellular matrix receptors, the integrins. In the normal kidney, interstitial fibroblasts express alpha1, alpha4, alpha5, and beta1 integrins, and fibrosis is associated with increased expression of alpha1, alpha2, alpha5, alphav, and beta1 integrins. In particular, alpha5, beta1, and alphav are suggested to be linked with the fibrotic process. In vitro, renal fibroblasts express a similar range of integrins, and ligation of selected receptors is associated with specific functions. Ligation of alpha6 stimulates proliferation, while alpha5 promotes expression of myofibroblastic phenotype, and beta1 integrin has been implicated in cell contraction. Recent studies suggest that renal fibroblasts also express the non-integrin matrix receptors, discoidin domain receptors, and that changes in activation of these receptors may be associated with fibrogenic events. Thus the current, albeit limited, data suggest an important role for receptors for extracellular matrix molecules in the pathogenesis of progressive renal fibrosis.
The First Direct and Enantioselective Cross-Aldol Reaction of Aldehydes (2002)

The first enantioselective catalytic direct cross-aldol reaction that employs nonequivalent aldehydes has been accomplished using proline as the reaction catalyst. Structural variation in both the aldol donor (R1 = Me, n-Bu, Bn, 91 to >99%) and aldol acceptor (R2 = I-Pr, I-Bu, c-C6H11, Et, Ph, 97-99% ee) are possible while maintaining high reaction efficiency (75-88% yield). Significantly, this new aldol variant allows facile enantioselective access to a broad range of beta-hydroxy aldehydes which are valuable intermediates in polyketide syntheses.
Real-time vehicle tracking in image sequences (2002)

We present an algorithm for tracking vehicles through an image sequence. The algorithm is based on matching a model in the image plane to each observed vehicle. The model is based on the characteristic edges of an intensity image of a vehicle. This model is applied to track vehicles through image sequences. We introduce three refinements to a standard model based tracking approach. As a first refinement, we use Kalman filtering to control the position and scale of the models. A multiple hypotheses strategy is suggested to avoid mismatches to local edges with a similar structure as (a part of) the model. As a last refinement we dynamically adapt each model to the vehicle if is being matched to. The refined model is more characteristic for the tracked vehicle and therefore increases the accuracy and robustness of the track. Each of these refinements contributes in their own way to a better overall performance of the tracking algorithm. We show that vehicles can be tracked in real-time with off the shelf processing capabilities and that our method is capable to track objects in ambiguous situations. Experiments based on practical data are presented to underline these conclusions.
Duration of protective efficacy of equine influenza immunostimulating complex/tetanus vaccines (1994)

Seven previously untreated five-month-old New Forest ponies received two doses of equine influenza immunostimulating complex vaccines, one with and one without an immunopurified tetanus toxoid component, given by deep intramuscular injection six weeks apart, followed by a booster dose without tetanus toxoid five months later. Fifteen months after the third dose of vaccine, the ponies were challenged by exposure to an aerosol of influenza A/Equine 2/Sussex/89 (H3N8), a virus isolated from a recent outbreak of influenza A/equine 2 in Britain. The challenge produced severe clinical signs of influenza (pyrexia and coughing) in five unvaccinated control ponies. Four of the vaccinated ponies were completely protected against clinical disease, and two of these were also protected against infection as demonstrated by their lack of an antibody response after challenge. No coughing was recorded among the vaccinated ponies, and only three of the seven vaccinated ponies experienced a transient mild pyrexia. The mean duration and severity of the pyrexia among the vaccinated ponies was significantly less (P < 0.01) than among the controls, and the excretion of virus was almost eliminated, thus demonstrating the protective efficacy of the vaccines 15 months after vaccination. Monitoring of tetanus antitoxin antibodies showed that protective levels (> or = 0.01/iu/ml) were maintained for at least 20 months after vaccination.
Vascular Endothelial Growth Factor Blockade Reduces Intratumoral Regulatory T Cells and Enhances the Efficacy of a GM-CSF–Secreting Cancer Immunotherapy (2006)

GM-CSF-secreting cancer immunotherapy and VEGF blockade increases the i.t. ratio of effector to regulatory T cells to provide enhanced antitumor responses. This therapeutic combination may prove to be an effective strategy for the treatment of patients with cancer.
Stimulated radiation from single crystals of BaYb/sub 2/F/sub 8/-Pr/sup 3 +/ (1987)

The authors have grown single crystals of BaYb/sub 2/F/sub 8/-Pr/sup 3 +/ and at about 110 K have excited Se at the waves of the inter-Stark transitions of the two intermultiplet channels /sup 1/G/sub 4/ ..-->.. /sup 3/H/sub 4/ and /sup 1/G/sub 4/ ..-->.. /sup 3/F/sub 4/ of their activator ions. The results have increased the number of generation channels of Ln/sup 3 +/ activators in the monoclinic fluorides Ba(Y, Ln)/sub 2/F/sub 8/ to 23 and broadened the IR limit of their SE range to 3.6 ..mu..m.
In vitro biocompatibility assessment of sulfonated polyrotaxane‐immobilized polyurethane surfaces (2003)

Sulfonated polyrotaxanes (PRx-SO(3)'s), in which sulfonated alpha-cyclodextrins (alpha-CDs) were threaded onto the poly(ethylene glycol) (PEG) segments in a PEG-b-poly(propylene glycol) (PPG)-b-PEG triblock copolymer (Pluronic) capped with benzyloxycarbonyl (Z)-L-phenylalanine (Z-L-Phe), were prepared as a novel surface-modifying biomaterial. Surface modification of the polyurethane (PU) was carried out by blending the PRx-SO(3)'s with a PU solution, followed by solution casting. The incorporated PRx-SO(3)'s led to the enhanced hydrophilicity by changing the surface properties of the PU matrix. Modified PUs showed the stable entrapment of the PRx-SO(3)'s with little extraction into water and enhanced mechanical properties after exposure to water compared to the PU control. The incorporated PRx-SO(3)'s repelled the proteins and kept them from closely approaching the surface areas, prevented platelet activation by thrombin, and effectively repelled bacteria. These results suggest that both the supramolecular structure of the polyrotaxanes and exposure of the sulfonated groups onto the surfaces contribute to these phenomena. Thus, surface modification with PRx-SO(3)'s is suggested to be useful for the fabrication of biocompatible medical devices.
Human platelet osteonectin: release, surface expression, and partial characterization (1990)

Our laboratory has previously shown that osteonectin, an abundant noncollagenous bone protein, is contained in and secreted from human platelets. In this study, the distribution of osteonectin both in the supernatant and on the platelet surface after activation was measured by fluid-phase and solid-phase radioimmunoassay, respectively. Total cellular osteonectin was determined by RIA of guanidinium chloride extracted platelets and ranged from 0.65 to 2.2 micrograms/10(8) platelets or 135,000 to 457,000 molecules/platelet. Platelets treated with varying concentrations of collagen and thrombin released osteonectin in a dose-dependent fashion. Approximately 61% of the total platelet osteonectin was secreted at saturating concentrations of collagen and thrombin. A small fraction of platelet osteonectin is expressed on the surface of platelets in an activation-specific manner as evidenced by the specific and saturable binding of [125I]-anti- osteonectin monoclonal antibody, IIIA3A8, to thrombin-activated platelets. Based on a non-linear least squares regression analysis of the antibody binding, 2,200 IIIA3A8 molecules, or 0.8% of the total platelet osteonectin, is expressed on the platelet surface on activation. Platelet osteonectin was purified from the supernatant of thrombin-activated platelets by immunoaffinity chromatography. Western blotting of proteins secreted by washed, thrombin-stimulated platelets with IIIA3A8 indicated that the osteonectin molecule released from the platelet is a single chain polypeptide. Comparison of immunopurified platelet osteonectin with isolated bovine bone osteonectin and isolated human bone osteonectin by sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that platelet osteonectin has a greater apparent molecular weight than bone osteonectin. The NH2-terminal sequence of immunopurified platelet osteonectin was obtained by automated Edman degradation and is identical to the sequence of human bone osteonectin derived from the cDNA of SaOS-2 cells. Collectively, these data suggest that platelet osteonectin is structurally distinct from bone osteonectin in a region of the molecule at a distance from the NH2-terminus.