gebhart/patrepeval huggingface dataset:
Sustained signaling leading to T cell activation results from prolonged T cell receptor occupancy. Role of T cell actin cytoskeleton. (1995)

Using antigen-specific T cell clones and peptide-pulsed antigen-presenting cells (APCs) we investigated the mechanisms that lead to sustained signaling, known to be required for activation of effector function. Four lines of evidence indicate that the T cell actin cytoskeleton plays a crucial role in T cell activation by antigen-pulsed APCs, but is not required when T cell receptor (TCR) is cross-linked by soluble antibodies. First, addition of antibodies to the major histocompatibility complex molecules recognized by the TCR aborts the ongoing intracellular calcium concentration ([Ca2+]i) increase in performed T-APC conjugates, indicating that the sustained signaling requires the continuous occupancy of TCR. Second, time-lapse image recording shows that T lymphocytes conjugated to peptide-pulsed APCs undergo a sustained [Ca2+]i increase, which is accompanied by the formation of a large and changing area of contact between the two opposing membranes. Third, drugs that disrupt the actin cytoskeleton, Cytochalasin D and and C2 Clostridium botulinum toxin induce a rapid block of [Ca2+]i rise, coincident with a block of the cyclic changes in T cell shape. Finally, the addition of Cytochalasin D or of anti-MHC antibodies to preformed conjugates inhibits interferon gamma production in an 1-antigen dose- and time-dependent fashion. These results identify T cell actin cytoskeleton as a major motor for sustaining signal transduction and possibly for driving TCR cross-linking and offer an explanation for how T cells equipped with low affinity TCR can be triggered by a small number of complexes on APCs.
Hybrid hepatitis B virus nucleocapsid bearing an immunodominant region from hepatitis B virus surface antigen (1993)

A hepatitis B core antigen (HBcAg) gene bearing the 39-amino-acid-long domain A of hepatitis B surface antigen (HBsAg) within the HBcAg immunodominant loop has been constructed and expressed in Escherichia coli. Chimeric capsids demonstrated HBs but not HBc antigenicity and elicited in mice B-cell and T-cell responses against native HBcAg and HBsAg.
Polymerase chain reaction assay of parvovirus B19 DNA in clinical specimens (1989)

The polymerase chain reaction (PCR) was used to detect parvovirus B19 DNA in a panel of sera from individuals recently infected with B19, as demonstrated by the presence of anti-B19 immunoglobulin M. Of 95 serum samples, 60 (63%) were found positive by PCR, whereas only 1 was also found positive by dot hybridization. In a control panel of 100 serum samples from individuals with other infections, only 1 serum sample was found positive by PCR, and this was also found positive by dot hybridization. This was probably just a fortuitous discovery of viremia. Placental tissues from women (n = 89) who had proven B19 infections in pregnancy but who gave birth to healthy infants at term were also tested. A total of 74 (83%) were found positive for B19 DNA by PCR. The high rate of detection by PCR probably represents "decay" of viral DNA after the peak of viremia and is not a clinically significant phenomenon.
Cross-Species Genome Wide Expression Analysis during Pluripotent Cell Determination in Mouse and Rat Preimplantation Embryos (2012)

The transition between morula and blastocyst stage during preimplantation development represents the first differentiation event of embryogenesis. Morula cells undergo the first cellular specialization and produce two well-defined populations of cells, the trophoblast and the inner cell mass (ICM). Embryonic stem cells (ESCs) with unlimited self-renewal capacity are believed to represent the in vitro counterpart of the ICM. Both mouse and rat ESCs can be derived from the ICM cells, but their in vitro stability differs. In this study we performed a microarray analysis in which we compared the transcriptome of mouse and rat morula, blastocyst, and ICM. This cross-species comparison represents a good model for understanding the differences in derivation and cultivation of ESCs observed in the two species. In order to identify alternative regulation of important molecular mechanisms the investigation of differential gene expression between the two species was extended at the level of signaling pathways, gene families, and single selected genes of interest. Some of the genes differentially expressed between the two species are already known to be important factors in the maintenance of pluripotency in ESCs, like for example Sox2 or Stat3, or play a role in reprogramming somatic cells to pluripotency like c-Myc, Klf4 and p53 and therefore represent interesting candidates to further analyze in vitro in the rat ESCs. This is the first study investigating the gene expression changes during the transition from morula to blastocyst in the rat preimplantation development. Our data show that in the pluripotent pool of cells of the rat and mouse preimplantation embryo substantial differential regulation of genes is present, which might explain the difficulties observed for the derivation and culture of rat ESCs using mouse conditions.
Simultaneous Electrical and Mechanical Mapping Using 3D Cardiac Mapping System: Novel Approach for Optimal Cardiac Resynchronization Therapy (2009)

Cardiac resynchronization therapy (CRT) restores synchrony in heart failure patients. However, a significant proportion of patients implanted with CRT devices do not realize any benefit from CRT. Placing a left ventricular (LV) lead at the sites of electrical or mechanical delay has been advocated to maximize response to CRT, but there is currently no technique described to measure mechanical delay in real-time. We describe a novel technique that can be used intraoperatively to assess mechanical and electrical activation of the coronary sinus for guidance of LV pacing site optimization during CRT implantation.
Ruthenium(II)-Catalyzed Asymmetric Transfer Hydrogenation of Ketones Using a Formic Acid−Triethylamine Mixture (1996)

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTRuthenium(II)-Catalyzed Asymmetric Transfer Hydrogenation of Ketones Using a Formic Acid−Triethylamine MixtureAkio Fujii, Shohei Hashiguchi, Nobuyuki Uematsu, Takao Ikariya, and Ryoji NoyoriView Author Information ERATO Molecular Catalysis Project Research Development Corporation of Japan 1247 Yachigusa, Yakusa-cho, Toyota 470-03, Japan Cite this: J. Am. Chem. Soc. 1996, 118, 10, 2521–2522Publication Date (Web):March 13, 1996Publication History Received7 December 1995Published online13 March 1996Published inissue 1 January 1996https://doi.org/10.1021/ja954126lCopyright © 1996 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views16429Altmetric-Citations942LEARN 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 InReddit Read OnlinePDF (126 KB) Get e-AlertsSupporting Info (2)»Supporting Information Supporting Information SUBJECTS:Alcohols,Hydrogen,Ketones,Mixtures,Transfer reactions Get e-Alerts
Gene expression profiling of liver metastases and tumour invasion in pancreatic cancer using an orthotopic SCID mouse model (2007)

The prognosis of pancreatic adenocarcinoma is affected by early metastases and local tumour invasion beyond surgical margins. Gene expression profiling in pancreatic cancer tissue is complicated due to the high amount of RNAses being present in human tissue and that of suitable models. In order to demonstrate early metastases, the models should take into account the anatomical environment of the tumour. Using the orthotopic transplantation of pancreatic tumour cells in SCID (severe combined immunodeficiency) mice, these interactions are taken into consideration. In order to identify genes associated with local tumour invasion and metastases in ductal pancreatic cancer, we investigated a human pancreatic tumour cell line derived from an orthopic pancreatic tumour model in SCID mice. Differential gene expression was performed on the basis of microarray technique. The human MiaPaca-2 cell line was implanted orthotopically in SCID mice. Transcriptional profiling was performed on fresh frozen tissue derived from the primary tumour, the tumour invasion front and the liver metastases. Differentially expressed genes were identified using statistical analyses, and were validated with external databases and with immunohistochemistry. A total of 1066 of 14 500 genes were significantly differentially expressed. Comparing the primary tumour with the tumour invasion front, there were 614 statistically significant up- and 348 downregulated genes. Twenty-five statistically significant up- and 181 downregulated genes were identified comparing the liver metastases with the primary tumour. Eight genes (PAI-1, BNIP3l, VEGF, NSE, RGS4, HSP27, GADD45A, PTPN14) were chosen and validated in a semi-quantitative immunohistochemical analysis, which revealed a positive correlation to the array data. Overrepresentation analyses revealed a total of 66 significantly regulated pathways associated with cell proliferation, cell stress, cell communication metabolic and cytokine function. In conclusion, model marker genes for local invasion and liver metastases can be identified using transcriptional profiling in the SCID mouse. Overrepresentation analysis secures a good and fast overview about the significantly regulated genes and can assign genes to certain pathways. These marker genes can be related to the apoptotic cascade, angiogenesis and cell interaction.
Oxidation products of fused 2-hetarylimidazole derivatives (2011)

Oxidation of 5-(1-methyl-1H-benzimidazol-2-yl)thiophene-, and -selenophene-2-carbaldehydes with potassium dichromate in 20% aqueous sulfuric acid afforded the corresponding carboxylic acids. Analogous reaction with 5-(1-methyl-1H-benzimidazol-2-yl)furan-2-carbaldehyde led to the formation of 1-methyl-1H-benzimidazole as a result of decarboxylation of the primary oxidation product and subsequent decomposition of the furan ring. Probable factors responsible for instability of 5-(1H-benzimidazol-2-yl)-hetarene-2-carboxylic acids were considered. The oxidation of 2-furylnaphtho[2,3-d]- and 2-hetarylphenanthro-[9,10-d]imidazoles gave, respectively, an anthraquinone analog and 6,7-quinones. π-Electron-rich heterocycles in 2-furyl- and 2-pyrrolylphenanthro[9,10-d]imidazoles were oxidized completely, being replaced by hydrogen.
Site‐directed mutagenesis of the putative catalytic residues of Trichoderma reesci cellobiohydrolase I and endoglucanase I (1990)

Site directed mutagenesis has been performed to test hypotheses concerning the putative active sites of Trichoderma reesei cellobiohydrolase I and endoglucanase I. It is shown that mutagenesis of the residue E126, previously proposed to be the proton donor in CBHI, did not totally inactivate the enzyme while mutagenesis of the residue E127 in the homologous enzyme EGI resulted in complete loss of activity. These results are compared with those obtained in similar studies of other glucanases and the effects on enzymatic activity of hyperglycosylation of the yeast produced cellulases are discussed.
Saccharomyces cerevisiae null mutants in glucose phosphorylation: metabolism and invertase expression. (1991)

A congenic series of Saccharomyces cerevisiae strains has been constructed which carry, in all combinations, null mutations in the three genes for glucose phosphorylation: HXK1, HXK2 and GLK1, coding hexokinase 1 (also called PI or A), hexokinase 2 (PII or B), and glucokinase, respectively: i.e., eight strains, all of which grow on glucose except for the triple mutant. All or several of the strains were characterized in their steady state batch growth with 0.2% or 2% glucose, in aerobic as well as respiration-inhibited conditions, with respect to growth rate, yield, and ethanol formation. Glucose flux values were generally similar for different strains and conditions, provided they contained either hexokinase 1 or hexokinase 2. And their aerobic growth, as known for wild type, was largely fermentative with ca. 1.5 mol ethanol made per mol glucose used. The strain lacking both hexokinases and containing glucokinase was an exception in having reduced flux, a result fitting with its maximal rate of glucose phosphorylation in vitro. Aerobic growth of even the latter strain was largely fermentative (ca. 1 mol ethanol per mol glucose). Invertase expression was determined for a variety of media. All strains with HXK2 showed repression in growth on glucose and the others did not. Derepression in the wild-type strain occurred at ca. 1 mM glucose. The metabolic data do not support- or disprove-a model with HXK2 having only a secondary role in catabolite repression related to more rapid metabolism.
Polymorphe Modifikationen und Solvate von Psilocin und Psilocybin (1976)

Abstract Von Psilocin konnten drei polymorphe Modifikationen dargestellt werden, die sich durch ihr Verhalten beim Kristallisieren und Schmelzen sowie durch ihre IR‐Spektren unterscheiden. Mod. I schmilzt bei 170–173°, Mod. II bei 161°, Mod, III wird immer umgewandelt; ihr Schmp. konnte nicht bestimmt werden. Diese Form läßt sich dagegen durch ihr IR‐Spektrum sehr gut charakterisieren. Psilocybin ist ein Solvatbildner, polymorphe Formen wurden nicht gefunden. Nach der Desolvation, die am Hydrat bei ca. 100° und am Methanolsolvat bei ca. 145° erfolgt, entsteht aus beiden Solvaten die gleiche lösungsmittelfreie Form, die je nach Versuchsbedingungen zwischen 210 und 230° unter Zersetzung schmilzt.
Identification of Single Human Hematopoietic Stem Cells Capable of Long-Term Multilineage Engraftment and Self-Renewal. (2009)

Abstract Abstract 816 A fundamental tenet that has guided our insight into the biology of hematopoietic stem cells (HSCs) over the past 50 years is the principle that an HSC can only be assayed by functional repopulation of an irradiated host1. In its strictest definition, only a HSC can provide long-term reconstitution of all the major lineages following single cell transplantation. However, the existing strategies for human HSC isolation lack quantitation and do not submit to this rigorous standard, thus precluding further biological analysis. Here, we report the prospective and quantitative analysis of human cord blood (CB) HSCs transplanted into female NOD/SCID/IL-2Rgcnull mice. We identify integrin a6 (CD49f) as a novel marker of cord blood (CB) HSCs and report that single Lin-CD34+CD38-CD90+CD45RA-RholoCD49fhi cells can reconstitute myeloid, B-, and T-cell lineages for 18 weeks. 5 of 29 mice transplanted with single cells gave rise to human cells indicating that approximately 20% of cells in this fraction are HSCs. This advance finally enables utilization of near-homogeneous populations of human HSCs to gain insight into their biology and to harness them for stem cell-based therapeutics. Disclosures: No relevant conflicts of interest to declare.
VIB-1 Is Required for Expression of Genes Necessary for Programmed Cell Death in Neurospora crassa (2006)

Nonself recognition during somatic growth is an essential and ubiquitous phenomenon in both prokaryotic and eukaryotic species. In filamentous fungi, nonself recognition is also important during vegetative growth. Hyphal fusion between genetically dissimilar individuals results in rejection of heterokaryon formation and in programmed cell death of the fusion compartment. In filamentous fungi, such as Neurospora crassa, nonself recognition and heterokaryon incompatibility (HI) are regulated by genetic differences at het loci. In N. crassa, mutations at the vib-1 locus suppress nonself recognition and HI mediated by genetic differences at het-c/pin-c, mat, and un-24/het-6. vib-1 is a homolog of Saccharomyces cerevisiae NDT80, which is a transcriptional activator of genes during meiosis. For this study, we determined that vib-1 encodes a nuclear protein and showed that VIB-1 localization varies during asexual reproduction and during HI. vib-1 is required for the expression of genes involved in nonself recognition and HI, including pin-c, tol, and het-6; all of these genes encode proteins containing a HET domain. vib-1 is also required for the production of downstream effectors associated with HI, including the production of extracellular proteases upon carbon and nitrogen starvation. Our data support a model in which mechanisms associated with starvation and nonself recognition/HI are interconnected. VIB-1 is a major regulator of responses to nitrogen and carbon starvation and is essential for the expression of genes involved in nonself recognition and death in N. crassa.
Growth of Rhodospirillum rubrum on synthesis gas: Conversion of CO to H2 and poly‐β‐hydroxyalkanoate (2006)

To examine the potential use of synthesis gas as a carbon and energy source in fermentation processes, Rhodospirillum rubrum was cultured on synthesis gas generated from discarded seed corn. The growth rates, growth and poly-beta-hydroxyalkanoates (PHA) yields, and CO oxidation/H(2) evolution rates were evaluated in comparison to the rates observed with an artificial synthesis gas mixture. Depending on the gas conditioning system used, synthesis gas either stimulated or inhibited CO-oxidation rates compared to the observations with the artificial synthesis gas mixture. Inhibitory and stimulatory compounds in synthesis gas could be removed by the addition of activated charcoal, char-tar, or char-ash filters (char, tar, and ash are gasification residues). In batch fermentations, approximately 1.4 mol CO was oxidized per day per g cell protein with the production of 0.75 mol H(2) and 340 mg PHA per day per g cell protein. The PHA produced from R. rubrum grown on synthesis gas was composed of 86% beta-hydroxybutyrate and 14% beta-hydroxyvalerate. Mass transfer of CO into the liquid phase was determined as the rate-limiting step in the fermentation.
The HDSL environment (high bit rate digital subscriber line) (1991)

The author presents a tutorial on the physical environment in which high bit rate digital subscriber line (HDSL) transceivers will have to evolve and succeed. Special attention is given to the most damaging impairments that are encountered in subscriber lines, such as propagation loss, linear distortion, crosstalk, bridged taps, and impulse noise. Somewhat less important impairments, such as change of gauge, temperature variation, and thermal noise, are also briefly described. The author concludes with a discussion of the capacity of a twisted-pair channel in a crosstalk-dominated environment.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Human Skeletal Muscle Insulin Receptor Substrate-1: Characterization of the cDNA, Gene, and Chromosomal Localization (1993)

Insulin receptor substrate-1 is a major substrate of insulin receptor Tyr kinase. We have now cloned the IRS-1 cDNA from human skeletal muscle, one of the most important target tissues of insulin action, localized and cloned the human IRS-1 gene, and studied the expression of the protein in Chinese hamster ovary cells. Human IRS-1 cDNA encodes a 1242 amino acid sequence that is 88% identical with rat liver IRS-1. The 14 potential Tyr phosphorylation sites include 6 Tyr-Met-X-Met motifs and 3 Tyr-X-X-Met motifs that are completely conserved in human IRS-1. Human IRS-1 has > 50 possible Ser/Thr phosphorylation sites and one potential ATP-binding site close to the NH2-terminal. The human IRS-1 gene contains the entire 5'-untranslated region and protein coding region in a single exon and was localized on chromosome 2 q36-37 by in situ hybridization. By Northern blot analysis, IRS-1 mRNA is rare and consists of two species of 6.9 and 6 kilobase. By using quantitative polymerase chain reaction after reverse transcription of total RNA from human fetal tissues, IRS-1 mRNA could be identified in all tissues. When human IRS-1 cDNA was expressed in Chinese hamster ovary cells, the protein migrated between 170,000-180,000 M(r) in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and was rapidly Tyr phosphorylated upon insulin stimulation. Thus, IRS-1 is widely expressed and highly conserved across species and tissues.(ABSTRACT TRUNCATED AT 250 WORDS)
Novel thin film titanium nitride micro-electrodes with excellent charge transfer capability for cell stimulation and sensing applications (2002)

Microelectrodes with high specific charge transfer capability are an important prerequisite for high resolution stimulation, and recording of neuronal and muscular tissue. Novel thin film titanium nitride (TiN) microelectrodes were fabricated onto a microelectrode array by reactive sputtering in a nitrogen/argon atmosphere. The electrodes showed excellent charge transfer capacity of 40 mC/cm/sup 2/ and low ac-impedance along with high pulse stability. Scanning electron microscopy revealed a regular columnar morphology providing for a large internal surface area. With respect to their electrical and mechanical properties the TiN electrodes proved superior to electrodes produced by anodic oxidation of iridium. In this type of iridium oxide irregular cracks formed probably due to the high density ratio between metal and oxide. Furthermore, in spite of high charge capacity at very low frequencies (Q/sub cap/) the iridium oxide electrodes exhibited poor safe charge injection limit under pulsing conditions (Q/sub inj/).
The Role of Herpes Simplex Virus-1 Thymidine Kinase Alanine 168 in Substrate Specificity (2008)

Herpes simplex virus type 1 (HSV) thymidine kinase (TK) has been widely used in suicide gene therapy for the treatment of cancer due to its broad substrate specificity and the inability of the endogenous human TK to phosphorylate guanosine analogs such as ganciclovir (GCV). The basis of suicide gene therapy is the introduction of a gene that encodes a prodrug-activating enzyme into tumor cells. After administration, the prodrug is selectively converted to a toxic drug by the suicide gene product thereby bringing about the eradication of the cancer cells. A major drawback to this therapy is the low activity the enzyme displays towards the prodrugs, requiring high prodrug doses that result in adverse side effects. Earlier studies revealed two HSV TK variants (SR39 and mutant 30) derived by random mutagenesis with enhanced activities towards GCV in vitro and in vivo. While these mutants contain multiple amino acid substitutions, molecular modeling suggests that substitutions at alanine 168 (A168) may be responsible for the observed increase in prodrug sensitivity. To evaluate this, site-directed mutagenesis was used to individually substitute A168 with phenylalanine or tyrosine to reflect the mutations found in SR39 and mutant 30, respectively. Additionally, kinetic parameters and the ability of these mutants to sensitize tumor cells to GCV in comparison to wild-type thymidine kinase were determined.
Annotation for the Deep Web (2003)

One of the core challenges of the Semantic Web is to create metadata by mass collaboration. A solution to this problem is a technique called deep annotation, which uses three elements of information-the information itself, its structure, and its context-to derive mappings.