gebhart/patrepeval huggingface dataset:
T cell clones from an X-linked hyper-immunoglobulin (IgM) patient induce IgE synthesis in vitro despite expression of nonfunctional CD40 ligand. (1994)

The induction of immunoglobulin E (IgE) switching in B cells requires at least two signals. The first is given by either of the soluble lymphokines interleukin 4 (IL-4) or IL-13, whereas the second is contact dependent. It has been widely reported that a second signal can be provided by the CD40 ligand (CD40L) expressed on the surface of T cells, mast cells, and basophils. A defect in the CD40L has been shown recently to be responsible for the lack of IgE, IgA, and IgG, characteristic of the childhood X-linked immunodeficiency, hyper IgM syndrome (HIGM1). IgE can however be detected in the serum of some HIGM1 patients. In this study, we isolated T cell clones and lines using phytohemagglutinin (PHA) and allergen, respectively, from the peripheral blood of one such patient who expressed a truncated form of CD40L, and investigated their ability to induce IgE switching in highly purified, normal tonsillar B cells in vitro. Unexpectedly, 4 of 12 PHA clones tested induced contact-dependent IgE synthesis in the presence of exogenous IL-4. These clones were also shown to strongly upregulated IL-4-induced germline epsilon RNA and formed dense aggregates with B cells. Of the four helper clones, three were CD8+, of which two were characteristic of the T helper cell 2 (Th2) subtype. Two allergen-specific HIGM1 T cell lines, both of the Th0 subtype, could also drive IgE synthesis when prestimulated using specific allergen. All clones and lines were negative for surface expression of CD40L, and the mutated form of CD40L was confirmed for a representative clone by RNase protection assay and sequencing. The IgE helper activity could not be attributed to membrane tumor necrosis factor alpha (TNF-alpha) although it was strongly expressed on activated clones, and the addition of neutralizing anti-TNF-alpha antibody did not abrogate IgE synthesis. These results therefore suggest the involvement of T cell surface molecules other than CD40L in the induction of IgE synthesis, and that these molecules may also be implicated in other aspects of T-B cell interactions.
Biliary epithelial and hepatocytic cell lineage relationships in embryonic rat liver as determined by the differential expression of cytokeratins, alpha-fetoprotein, albumin, and cell surface-exposed components. (1988)

The differentiation patterns of epithelial cells in fetal rat liver were analyzed in situ and in primary culture by indirect immunofluorescence microscopy using polyvalent and monoclonal antibodies directed against cytokeratins with molecular weights of 55,000 (CK55), 52,000 (CK52), and 39,000 (CK39) and against vimentin, albumin, alpha-fetoprotein, and surface-exposed components of bile ductular cells (BDS7) and hepatocytes (HES6). The anti-CK52 antibody, which reacted with biliary ductal cells in the liver of adult rats (Germain et al., Cancer Res., 45:673, 1985; Germain et al., Cancer Res., 48: 368-378, 1988), stained essentially all of the epithelial cells of embryonic day 12 (E12) rat liver. The anti-BDS7 antibody reacted with a few cell foci, which enlarged and became more numerous at later developmental ages. At E12 essentially all of the cells were positive for albumin and alpha-fetoprotein but did not express HES6. In fact HES6 was not detected until E15 in cells with the morphology of immature hepatocytes. By E18 staining with anti-HES6 reached the level of that observed on adult rat hepatocytes. Liver cells isolated from E12 rats were seeded on fibronectin-treated dishes and their response to various combinations of growth- and differentiation-promoting factors was evaluated with respect to their capacity to express either the hepatocytic or the bile ductular phenotype. In medium supplemented with serum, insulin, dexamethasone, and dimethyl sulfoxide, the E12 cells were capable of differentiating in culture to mimic over a 6-day period the sequential phenotypic changes which occur in vivo during normal hepatoontogeny, namely the loss of CK52 and the appearance of HES6. In contrast, the addition of sodium butyrate to the above supplement mixture resulted in the massive expression of BDS7. To further assess the developmental potential of fetal rat liver cells toward the biliary epithelial cell lineage, the in vitro assay was performed using cells isolated from livers of E18 rats and also from 2-day-old (P2) and P14 rats. While a slight expression of BDS7 was induced in cell culture from E18 liver, essentially no expression was observed in cells from postnatal livers. These findings strongly suggest that the emerging hepatic tissue in rat embryo is composed of bipotential progenitor epithelial cells that are capable of differentiating along either the hepatocytic or biliary epithelial cell lineage. These observations constitute a clear demonstration of the plasticity of liver differentiation and also provide a striking example of environmental influences on liver progenitor cell differentiation.
A Low-Power Preamble Detection Methodology for Packet Based RF Modems on All-Digital Sensor Front-Ends (2007)

There is a growing trend towards networks of sensors in which each sensor wirelessly transmits digital data to a central data collection node. The transmission of sensor measurements relies on its digitized data being organized as a set of bits. This sequence or frame contains preamble information (the preamble is used to signal that "here is a train of data coming" to the receiver), a data sequence, and finally "end of signal" bits. In order to achieve frame synchronization in packet-based communication systems, a known sequence (pre-amble) is sent at the beginning of each packet. This paper presents a low power scheme for preamble detection using dynamic precision configuration. The proposed scheme is based on the observation that signal processing algorithms at the front end (including mixer, square root raised cosine (SRRC) matched filter and code matched filter (CMF)) of the receiver, can be operated with minimum precision during the acquisition phase without incurring significant acquisition performance degradation. The SRRC filter is designed to achieve minimize inter-symbol interference, while the CMF is designed to improve the signal to noise ratio. The result is an acquisition system design that consumes less than 25% of power dissipation that is consumed by other typical implementations.
Estimation of cardiac output in patients with congestive heart failure by analysis of right ventricular pressure waveforms (2011)

The analysis of right ventricular pressure waveforms continuously recorded by an implantable hemodynamic monitor provides an estimate of CO and may prove useful in guiding treatment in patients with CHF.
All-Solid-State Miniaturized Fluorescence Sensor Array for the Determination of Critical Gases and Electrolytes in Blood (1997)

We describe a six-channel, all-solid-state, miniaturized fluorescence sensor array for the precise determination of blood analytes for medical diagnostic purposes. The device features superblue LEDs as light sources, GRIN optics, and photodiodes, assembled according to pigtailing procedures (Bruno, A. E.; et al. Trends Anal. Chem. 1994, 13, 190-198). The numerical aperture of the fluorescence optics is 0.46, rendering a collection efficiency of 2.4%. The performance of this instrument has been evaluated in terms of dynamic response, linearity, channel reproducibility, reversibility, long-term drifts, photobleaching of indicator, cross-talk, ionic strength, and selectivity in pH measurements. The responses of the pH sensing membranes were optimized in the physiological range. Responses are linear with typical values of approximately 1.5 V/pH units, with limits of decision of 24 mV, which corresponds to pH resolutions of 0.03 pH unit. Under continuous illumination, using calibration buffers, the sensors display nonstatistical differences within 2 standard deviations over a period of 6 h, and it is shown that, under discontinuous illumination, the membranes can be used in more than 2000 measurements without need of calibration, in contrast to electrochemical sensors which require periodic calibration. After selecting the appropriate combination of LEDs, excitation and emission filters, and sensing membranes, the instrument was used to determine the concentrations of various critical blood analytes in buffer solutions in the various channels. Similar measurements in untreated blood reproduce the reported results.
In-car interaction using search-based user interfaces (2008)

Increasing functionality, growing media volumes and dynamic data in today's in-vehicle information systems bear new challenges for user interaction design. Traditional hierarchical and menu-based interaction can only provide limited support while new search-based approaches are promising. In this work we assess different search techniques and search-based user interfaces. In particular we compare free search across all data items with categorized search. Our experiments with functional prototypes show that free search is more efficient and easier to use than searching within categories. Tests in a driving simulator show promising results regarding safety and workload. Means for alphanumeric input appear to be essential for an efficient and safe search interaction while driving.
Frequency reuse for two co-existing TDMA personal communications systems (2003)

Two strategies to share radio spectrum for two co-existing personal communications systems are discussed. The implications on signal quality are examined by simulating wireless access for portable users and gathering the statistic of the signal to co-channel interference ratio. The author shows that, for two service providers to offer services in a common geographic region with interleaved port locations, it is preferable that the radio spectrum be partitioned between the two systems.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Native and recombinant herpes simplex virus type 1 envelope proteins induce human immune T-lymphocyte responses (1987)

The abilities of whole herpes simplex virus type 1 (HSV-1) antigen (HSV-ag) and purified HSV-1 native and recombinant envelope proteins to stimulate in vitro T-lymphocyte responses were compared in patients with recurrent herpes labialis. Immunochemically purified preparations of native glycoproteins B, C, and D (ngB, ngC, ngD) from cultured HSV-1 as well as expressed recombinant plasmid preparations of gD (rgD-1t, rgD-45K) elicited lymphocyte proliferation (LT) and production of gamma interferon (IFN-gamma) and interleukin-2 (IL-2) only in seropositive individuals. The IFN-gamma induced by rgD-1t correlated with the time to the next herpetic lesion in 19 volunteers followed to recurrence (r = 0.69, P less than 0.008), although the magnitude and frequency of LT and IFN-gamma responses were lower with either recombinant or native purified antigens than with the whole-virus antigen. Combinations of ngB plus ngD or ngB plus ngC plus ngD stimulated more IFN-gamma, equivalent to whole-virus-antigen responses. Recombinant-derived human IL-2 also specifically increased LT and IFN-gamma responses in antigen-driven cultures. ngD stimulated IL-2 and LT responses similar to those of whole-virus antigen and higher than those of ngC. HSV-ag and ngB induced significantly higher titers of total IFN than could be accounted for by IFN-gamma; this was not seen for the other antigens, which induced only IFN-gamma. HSV-ag-driven Leu 2a-, plastic-nonadherent blood cells, unlike whole peripheral blood mononuclear cells, showed evidence of an increase and then a decline in the frequency of HSV-responsive cells after a lesion recurrence. These studies suggest that HSV-1 envelope proteins are capable of stimulating an immune T-helper-cell response which is associated with the prevention of human herpes simplex lesion recurrence. Although the whole virus probably contains additional important antigens, increasing concentrations or combinations of certain purified glycoproteins or the addition of nonspecific enhancers of T-lymphocyte function can drive in vitro immune responses to the same level as the complete set of viral antigens.
Fatty acid profiles and their distribution patterns in microalgae: a comprehensive analysis of more than 2000 strains from the SAG culture collection (2011)

FA distribution patterns are suitable chemotaxonomic markers to define taxa of higher rank in algae. However, due to their extensive variation at the species level it is difficult to make predictions about the FA profile in a novel isolate.
Accessory cell function of keratinocytes for superantigens. Dependence on lymphocyte function-associated antigen-1/intercellular adhesion molecule-1 interaction (1993)

A growing body of evidence points to a role for epidermal keratinocytes as active participants in immunologic reactions. Inasmuch as certain T cell-mediated skin diseases, such as psoriasis and atopic dermatitis, are triggered by microbial infection, we asked whether multipassaged human keratinocytes could provide the costimulatory signals necessary to induce autologous T cell proliferation in response to bacterial-derived super-antigens. On exposure to IFN-gamma, keratinocytes are induced to express HLA-DR and HLA-DQ class II MHC Ag, and the lymphocyte function-associated Ag-1 counter-receptor intercellular adhesion molecule-1 (ICAM-1). This change in keratinocyte phenotype is accompanied by the ability of these cells to support T cell proliferation induced by two different bacterial-derived superantigens, staphylococcal enterotoxins A and B. Superantigen-driven proliferation in the presence of IFN-gamma-treated keratinocytes was significantly inhibited (70-90% reduction) by mAb against the LFA-1 alpha- or beta-chain or ICAM-1. Proliferation was not inhibited by mAb against the CD28 ligands BB-1 or B7, even though these keratinocytes express BB-1. In addition to previous defined roles for class II MHC Ag, stimulation of LFA-1 on the T cells by ICAM-1 on the keratinocytes also plays an important costimulatory role in this superantigen-mediated response. The accessory cell capability of keratinocytes was not unique to superantigen driven responses as PHA, as well as anti-CD3 mAb also induced vigorous T cell proliferation when IFN-gamma-treated keratinocytes were added. However, IFN-gamma-treated keratinocytes consistently failed to provoke an allogeneic response. These data demonstrate that 1) keratinocytes can serve as accessory cells for T cell proliferation using a variety of different stimuli, 2) the LFA-1/ICAM-1 interaction plays a major role in keratinocyte-mediated costimulation, and 3) previous reports in which IFN-gamma-treated keratinocytes failed to support T cell proliferation to nominal or alloantigens, may reflect impaired Ag presentation via class II MHC molecules, rather than lack of necessary costimulatory signals. These findings highlighting the accessory cell function of keratinocytes may have implications for our understanding of the pathogenesis of immunologic disorders of the skin.
Synthesis and Properties of Nucleic Acid Analogues Consisting of a Benzene−Phosphate Backbone (2005)

[Chemical reaction: See text] The synthesis and properties of a nucleic acid analogue consisting of a benzene-phosphate backbone are described. The building blocks of the nucleic acid analogue are composed of bis(hydroxymethyl)benzene residues connected to nucleobases via the biaryl-like axis. Stabilities of the duplexes were studied by thermal denaturation. It was found that the thermal stabilities of the duplexes composed of the benzene-phosphate backbone are highly dependent on their sequences. The duplexes with the benzene-phosphate backbone comprised of the mixed sequences were thermally less stable than the natural DNA duplexes, whereas that composed of the homopyrimidine and homopurine sequences was thermally and thermodynamically more stable than the corresponding natural DNA duplex. It was suggested that the analogues more efficiently stabilize the duplexes in a B-form duplex rather than in an A-form duplex. Thus, the duplexes consisting of the benzene-phosphate backbone, especially composed of the homopyrimidine and homopurine sequences, may offer a novel structural motif useful for developing novel materials applicable in the fields of bio- and nanotechnologies.
Reduction of Th1 cell activity in the peripheral circulation of patients with rheumatoid arthritis after treatment with a non-depleting humanized monoclonal antibody to CD4. (1998)

Clinical improvement in patients with RA treated with a non-depleting Mab to CD4 may be related to a decrease in the function of IL-2 and IFN-gamma producing Th1 cells.
18-MC reduces methamphetamine and nicotine self-administration in rats (2000)

In previous studies, 18-methoxycoronaridine (18-MC), a novel iboga alkaloid congener, has been found to decrease the intravenous self-administration of morphine and cocaine in rats. In the present study, 18-MC (1-40 mg/kg, i.p.) dose-dependently decreased the i.v. self-administration of methamphetamine and nicotine. As in the previous studies, drug self-administration was reduced for > or = 24 h after the highest dose of 18-MC. A comparison of 18-MC's interactions with all four drugs of abuse studied so far indicated that 18-MC is least effective in decreasing methamphetamine self-administration and most potent in decreasing nicotine self-administration. The results suggest that a nicotinic antagonist action of 18-MC contributes to its putative anti-addictive efficacy.
Design considerations for high power high frequency transformers (2002)

Various design considerations for high-power (multikilowatt), high-frequency transformers for DC-DC power converters are investigated. Although Ferrite (PC40) is lossier than Permalloy80 (0.5 mil) at the frequencies of interest (25-50 kHz) the use of the former is justified on the basis of cost, weight, and wide ranges of shapes. The influence of the leakage flux distribution in the window region on the copper losses has been demonstrated for various conventional winding arrangements. However, it is seen that in conventionally wound transformers a considerable amount of leakage flux enters the core, resulting in localized core saturation and hot-spots. This becomes a very critical issue for high-power, high-frequency transformers. Coaxially wound transformers are seen to be a viable alternative, in that the leakage flux is contained with the interwinding space, with very little or none of it permeating the core. Such transformers can also realize multiple benefits of a low distributed and controllable leakage inductance, robust construction, low electromechanical forces, and low core and copper losses. Test results on two coaxially wound transformers with different tube geometries, designed for 50 kW, 50 kHz, primary voltage of 200 V, and secondary voltage of 1000 V (two windings), are presented. Finally the concept of coaxial winding technique for three-phase transformers is also presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Factor XII-Driven Inflammatory Reactions with Implications for Anaphylaxis (2017)

Anaphylaxis is a life-threatening allergic reaction. It is triggered by the release of pro-inflammatory cytokines and mediators from mast cells and basophils in response to immunologic or non-immunologic mechanisms. Mediators that are released upon mast cell activation include the highly sulfated polysaccharide and inorganic polymer heparin and polyphosphate (polyP), respectively. Heparin and polyP supply a negative surface for factor XII (FXII) activation, a serine protease that drives contact system-mediated coagulation and inflammation. Activation of the FXII substrate plasma kallikrein leads to further activation of zymogen FXII and triggers the pro-inflammatory kallikrein-kinin system that results in the release of the mediator bradykinin (BK). The severity of anaphylaxis is correlated with the intensity of contact system activation, the magnitude of mast cell activation, and BK formation. The main inhibitor of the complement system, C1 esterase inhibitor, potently interferes with FXII activity, indicating a meaningful cross-link between complement and kallikrein-kinin systems. Deficiency in a functional C1 esterase inhibitor leads to a severe swelling disorder called hereditary angioedema (HAE). The significance of FXII in these disorders highlights the importance of studying how these processes are integrated and can be therapeutically targeted. In this review, we focus on how FXII integrates with inflammation and the complement system to cause anaphylaxis and HAE as well as highlight current diagnosis and treatments of BK-related diseases.
A hierarchical order of factors in the generation of FLK1- and SCL-expressing hematopoietic and endothelial progenitors from embryonic stem cells (2004)

The receptor tyrosine kinase FLK1 and the transcription factor SCL play crucial roles in the establishment of hematopoietic and endothelial cell lineages in mice. We have previously used an in vitro differentiation model of embryonic stem (ES) cells and demonstrated that hematopoietic and endothelial cells develop via sequentially generated FLK1(+) and SCL(+) cells. To gain a better understanding of cellular and molecular events leading to hematopoietic specification, we examined factors necessary for FLK1(+) and SCL(+) cell induction in serum-free conditions. We demonstrate that bone morphogenetic protein (BMP) 4 was required for the generation of FLK1(+) and SCL(+) cells, and that vascular endothelial growth factor (VEGF) was necessary for the expansion and differentiation of SCL-expressing hematopoietic progenitors. Consistently, Flk1-deficient ES cells responded to BMP4 and generated TER119(+) and CD31(+) cells, but they failed to expand in response to VEGF. The Smad1/5 and map kinase pathways were activated by BMP4 and VEGF, respectively. The overexpression of SMAD6 in ES cells resulted in a reduction of FLK1(+) cells. In addition, a MAP kinase kinase 1 specific inhibitor blocked the expansion of SCL(+) cells in response to VEGF. Finally, VEGF mediated expansion of hematopoietic and endothelial cell progenitors was inhibited by TGFbeta1, but was augmented by activin A. Our studies suggest that hematopoietic and endothelial commitment from the mesoderm occurs via BMP4-mediated signals and that expansion and/or differentiation of such progenitors is achieved by an interplay of VEGF, TGFbeta1 and activin A signaling.
Isolation and genetic characterization of Escherichia coli mutants defective in propionate metabolism (1981)

Escherichia coli mutants defective in propionate metabolism (Prp-) were isolated after mutagenesis with N-methyl-N'-nitro-N-nitrosoguanidine. Prp- mutants demonstrate a phenotypic inability to grow on odd-chain-length fatty acids. The new genetic locus for the Prp- phenotype maps at approximately 98 min on the E. coli chromosome.
Noncompetitive allosteric inhibitors of the inflammatory chemokine receptors CXCR1 and CXCR2: Prevention of reperfusion injury (2004)

The chemokine CXC ligand 8 (CXCL8)/IL-8 and related agonists recruit and activate polymorphonuclear cells by binding the CXC chemokine receptor 1 (CXCR1) and CXCR2. Here we characterize the unique mode of action of a small-molecule inhibitor (Repertaxin) of CXCR1 and CXCR2. Structural and biochemical data are consistent with a noncompetitive allosteric mode of interaction between CXCR1 and Repertaxin, which, by locking CXCR1 in an inactive conformation, prevents signaling. Repertaxin is an effective inhibitor of polymorphonuclear cell recruitment in vivo and protects organs against reperfusion injury. Targeting the Repertaxin interaction site of CXCR1 represents a general strategy to modulate the activity of chemoattractant receptors.