gebhart/patrepeval huggingface dataset:
Down-regulation of human basophil IgE and FC epsilon RI alpha surface densities and mediator release by anti-IgE-infusions is reversible in vitro and in vivo. (1999)

Previously, infusions of an anti-IgE mAb (rhumAb-E25) in subjects decreased serum IgE levels, basophil IgE and FcepsilonRIalpha surface density, and polyclonal anti-IgE and Ag-induced basophil histamine release responses. We hypothesized that these effects would be reversed in vivo by discontinuation of infusions and in vitro by exposing basophils to IgE. Subjects received rhumAb-E25 biweekly for 46 wk. Blood samples taken 0-52 wk after rhumAb-E25 were analyzed for serum IgE and basophil expression of IgE, FcepsilonRIalpha, and CD32. Basophil numbers were unaffected by infusions. Eight weeks after infusions, free IgE levels rose in vivo but did not reach baseline. Basophil IgE and FcepsilonRIalpha rose in parallel with free IgE while CD32 was stable. FcepsilonRI densities, measured by acid elution, returned to 80% of baseline, whereas histamine release responses returned to baseline. Basophils cultured with or without IgE or IgG were analyzed for expression of IgE, FcepsilonRIalpha, and CD32. By 7 days with IgE, expression of IgE and FcepsilonRIalpha rose significantly, whereas cultures without IgE declined. IgE culture did not effect CD32. IgG culture did not effect expression of any marker. The present results strongly suggest that free IgE levels regulate FcepsilonRIalpha expression on basophils.
Portable self-contained cultures for phage and bacteria made of paper and tape (2012)

In this paper, we demonstrate that a functional, portable device for the growth of bacteria or amplification of bacteriophage can be created using simple materials. These devices are comprised of packing tape, sheets of paper patterned by hydrophobic printer ink, and a polydimethyl siloxane (PDMS) membrane, which is selectively permeable to oxygen but non-permeable to water. These devices supply bacteria with oxygen and prevent the evaporation of media for a period over 48 h. The division time of E. coli and the amplification of the phage M13 in this device are similar to the rates measured on agar plates and in shaking cultures. The growth of bacteria with a fluorescent mCherry reporter can be quantified using a flatbed scanner or a cell phone camera. Permeating devices with commercial viability dye (PrestoBlue) can be used to detect low copy number of E. coli (1-10 CFU in 100 μL) and visualize microorganisms in environmental samples. The platform, equipped with bacteria that carry inducible mCherry reporter could also be used to quantify the concentration of the inducer (here, arabinose). Identical culture platforms can, potentially, be used to quantify the induction of gene expression by an engineered phage or by synthetic transcriptional regulators that respond to clinically relevant molecules. The majority of measurement and fabrication procedures presented in this report have been replicated by low-skilled personnel (high-school students) in a low-resource environment (high-school classroom). The fabrication and performance of the device have also been tested in a low-resource laboratory setting by researchers in Nairobi, Kenya. Accordingly, this platform can be used as both an educational tool and as a diagnostic tool in low-resource environments worldwide.
Mitogen and Substrate Differentially Affect the Lineage Restriction of Adult Rat Subventricular Zone Neural Precursor Cell Populations (1999)

The effects of specific mitogens and substrates on the proliferative capacity and the differentiated phenotypic plasticity of neural precursor cell populations isolated from the adult rat subventricular zone (SVZ) were examined. SVZ cells were grown on uncoated tissue culture plastic, extracellular matrix, or poly-D-ornithine with either laminin or fibronectin. SVZ neural precursor cells could not be generated with platelet-derived growth factor (PDGF), granulocyte macrophage colony stimulating factor, stem cell factor, heparin-binding epidermal growth factor (HB-EGF), granulocyte colony stimulating factor, or ciliary neurotrophic factor (CNTF), but could be with EGF, fibroblast growth factor 2 (FGF2), and FGF2 plus heparin. Varying combinations of substrate and mitogen resulted in very different expansion rates and/or lineage potential. Neurons, oligodendrocytes, and astrocytes differentiated from all cultures, but EGF-generated neural precursor cells were more restricted to an astrocytic lineage and FGF2-generated neural precursor cells had a greater capacity for neuronal differentiation. In both EGF- and FGF2-generated cell populations, CNTF increased the number of differentiated astrocytes, triiodothyronine oligodendrocytes, PDGF neurons, and brain-derived neurotrophic factor neurons only from EGF cells. Electrophysiological analysis of differentiated cells showed three distinct phenotypes, glial, neuronal, and presumed precursor cells, although the neuronal properties were immature. Collectively, these data indicate that CNS neural precursor cell populations isolated with different mitogens and substrates are intrinsically different and their characteristics cannot be directly compared.
Do artificial oligosaccharides in infant formula reduce the risk of atopic disease and allergies similar to human milk oligosaccharides (2012)

Allergies and atopic diseases constantly increase over the last decades. Genetic predisposition alone does not explain this epidemic rise. Consequently environmental factors have to play an important role. Especially early infant nutrition is thought to have a great impact on atopy development and its clinical manifestations. Human milk is broadly recommended as the best nutrition for infants. This indicates that in cases where breast-feeding is not an option infant formula should match human milk as close as possible. Therefore beneficial components of human milk should not be absent in infant formula. As important factors among, human milk oligosaccharides (HMO) have been identified. HMO are almost absent in bovine milk and therefore in bovine milk based infant formula. Broadly accepted are the prebiotic functions of HMO. Increasing evidence suggests various other beneficial functions of HMO like inhibition of pathogens upon competitive binding. The specific functions of HMO are thought to be determined by their various structures. HMOs are promising modulators of allergy and atopic disease development. Currently artificial synthesized oligosaccharides (GOS/FOS) are added to infant formula in order to mimic properties of HMOs. The molecular structures of enzymatically synthesized GOS and plant-derived FOS are much simpler and differ significantly from the highly complex structures of HMOs thus, it is unlikely that they can mimic all of the structure dependent functions of HMOs.
The aim of this thesis is to investigate if and how artificially synthesized oligosaccharides can mimic functions of naturally occurring HMO especially in regard to allergy and atopic disease development. General factors that possibly contribute to the atopy epidemic, mechanisms of the pathophysiology of atopy and its clinical manifestations as well as the role of some human milk components herein will be discussed first.
Michael Acceptors as a Tool for Anticancer Drug Design (1996)

Abstract: Interaction of antitumor drugs with cellular targets involves various types of chemical binding, of which covalent binding is one of important strategies in designing effective anticancer molecules. The anticancer compounds employing covalent binding, structurally diverse, belong to many chemical classes, including quinones, mustards, nitrosourea, alkylsulfonate, pyrrolo[l,4]benzodiazepines, and others. Most of these compounds contain, or acquire by cellular metabolism, electrophilic centers, and some are Michael acceptors in a broader sense. Recent evidences suggest that antineoplastic alkylating compounds bind directly to various cellular nucleophiles, thus lacking in a selectivity. Meanwhile, Michael acceptors can be structurally modified, so that they can react selectively with target nucleophiles or they can be converted into a selective Michael acceptors during metabolism. Moreover, we often meet these Michael acceptors in biochemical process of cellular respiration or in metabolisms of some drugs or xenobiotics. A group of representative natural cytotoxic compounds containing Michael acceptor are naphthoquinones such as menadione and shikonin analogues, cytotoxic quassinoids, sesquiterpenoid benzoquinones, and others. Mitomycin, meanwhile, is transformed by reductive activation into a conjugated dienone as a Michael acceptor. In this review, chemistry, cytotoxicity and antitumor action of anticancer agents containing Michael acceptors will be discussed in the respect of structure-activity relationship. More in-depth review will be given of the naphthazarin analogues. Also, cytotoxic terpenes such as ar-turmerone analogues, quassinoids, and others will be reviewed.
Suppression of growth and transformation and induction of apoptosis by EGR-1. (1998)

Although cloned as an "immediate-early gene," recent studies show that EGR-1 functions in growth regulation and suppression of transformation by transactivation of the transforming growth factor beta-1 (TGF-beta1) gene and cooperation with Sp1, Jun-B, p21WAF1/Cip1, and stimulates apoptosis by transactivation of the p53 gene.
Induction and Visualization of Mucosal Memory CD8 T Cells Following Systemic Virus Infection (1999)

Whether CD8 T cell memory exists outside secondary lymphoid organs is unclear. Using an adoptive transfer system that enables tracking of OVA-specific CD8 T cells, we explored the antigenic requirements for inducing CD8 T cell memory and identified intestinal mucosa memory cells. Although systemic immunization with soluble OVA induced clonal expansion, memory CD8 cells were not produced. In contrast, infection with virus-encoding OVA induced memory CD8 cells in the periphery and the lamina propria and intraepithelial compartments of the intestinal mucosa. Mucosal memory cells expressed a distinct array of adhesion molecules as compared with secondary lymphoid memory cells, suggesting that there may be separate mucosal and systemic memory pools. Mucosal CD8 memory cells rapidly produced IFN-gamma after Ag stimulation. Reactivation of memory cells by Ag feeding resulted in increased cell size and up-regulation of CD28 and CD11c. CD8 mucosal memory cells exhibited ex vivo lytic activity that was up-regulated dramatically following Ag reencounter in vivo. Interestingly, reactivation of memory cells did not require CD28-mediated costimulation. The ability of the intestinal mucosa to maintain CD8 memory cells provides a potential mechanism for effective mucosal vaccination.
Serologic identification of hepatitis E virus infections in epidemic and endemic settings (1992)

Recombinant chimeric protein C2 containing the N-terminal region of trpE (37 kilodaltons [kDa]) and the C-terminal half (46.8 kDa) of the polypeptide encoded by ORF2 of the hepatitis E virus (HEV) genome was used for the construction of a Western blot diagnostic test for IgG and IgM antibodies to the virus (anti-HEV). (The C2 protein and the trpE protein devoid of C2 activity and used as a control for non-specific reactions were purified by recovery from sodium dodecyl sulfate-polyacrylamide gel electrophoresis [SDS-PAGE] and used for preparation of strips). Specificity of the test was proven with sera obtained from patients with acute hepatitis non-A, non-B, non-C (NANBNC) from outbreaks in different geographic regions of the world. IgG antibodies reactive to the recombinant C2 protein were detected in 93% of patients with acute hepatitis NANBNC and remained detectable in 89-100% of these patients 1-24 months after onset of jaundice. IgM antibodies were detected in 73% of patients within 26 days after onset of jaundice, in 50% 1-4 months after onset, in 6% 6-7 months after onset, and in no patients by 8 months after onset. When this test was used to identify sporadic hepatitis E cases in different regions of the world, such cases were found almost exclusively in areas where outbreaks of the disease had occurred and rarely in any other regions.
TGF alpha enhances locomotion of cultured human keratinocytes. (1993)

A cDNA sequence coding for the full-length human transforming growth factor alpha (TGF alpha) precursor protein was introduced into and transcribed in cultured human keratinocytes, using a high-titer, high-expression, murine amphotropic retrovirus. Keratinocytes were shown capable of post-translationally modifying the TGF alpha primary translation product, with the subsequent formation of several cell-associated and secreted forms of TGF alpha, at least five of which, including the 50 amino acid mature species, can potentially bind and activate the epidermal growth factor receptor. Cells overexpressing the TGF alpha gene assumed a spindled morphology with long, bipolar filamentous processes and displayed increased locomotion. The soluble, mature form of TGF alpha alone also could induce the observed changes in cell shape and motility when added to keratinocyte cultures exogenously. The effects were dose dependent, and up to fourfold increases in locomotion were caused by TGF alpha in the absence of bovine pituitary extract (BPE). The addition of BPE to high concentrations of TGF alpha further enhanced keratinocyte motility to eightfold over baseline, suggesting a synergistic interaction between the two factors. These experiments demonstrate that keratinocytes can synthesize several forms of TGF alpha and that TGF alpha, besides being mitogenic, may have other important regulatory functions in keratinocytes.
Axing the accent (1994)

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Component Developments Extend System Performance (1993)

Reference LOA-ARTICLE-1993-005View record in Web of Science Record created on 2009-01-20, modified on 2017-05-10
New negative differential resistance device based on resonant interband tunneling (1989)

We propose and demonstrate a novel negative differential resistance device based on resonant interband tunneling. Electrons in the InAs/AlSb/GaSb/AlSb/InAs structure tunnel from the InAs conduction band into a quantized state in the GaSb valence band, giving rise to a peak in the current-voltage characteristic. This heterostructure design virtually eliminates many of the competing transport mechanisms which limit the performance of conventional double-barrier structures. Peak-to-valley current ratios as high as 20 and 88 are observed at room temperature and liquid-nitrogen temperature, respectively. These are the highest values reported for any tunnel structure.
A New Method to Derive White Matter Conductivity From Diffusion Tensor MRI (2008)

We propose a new algorithm to derive the anisotropic conductivity of the cerebral white matter (WM) from the diffusion tensor MRI (DT-MRI) data. The transportation processes for both water molecules and electrical charges are described through a common multicompartment model that consists of axons, glia, or the cerebrospinal fluid (CSF). The volume fraction (VF) of each compartment varies from voxel to voxel and is estimated from the measured diffusion tensor. The conductivity tensor at each voxel is then computed from the estimated VF values and the decomposed eigenvectors of the diffusion tensor. The proposed VF algorithm was applied to the DT-MRI data acquired from two healthy human subjects. The extracted anisotropic conductivity distribution was compared with those obtained by using two existing algorithms, which were based upon a linear conductivity-to-diffusivity relationship and a volume constraint, respectively. The present results suggest that the VF algorithm is capable of incorporating the partial volume effects of the CSF and the intravoxel fiber crossing structure, both of which are not addressed altogether by existing algorithms. Therefore, it holds potential to provide a more accurate estimate of the WM anisotropic conductivity, and may have important applications to neuroscience research or clinical applications in neurology and neurophysiology.
Synthesis and field emission of carbon nanotubular fibers doped with high nitrogen content (2003)

Nitrogen-doped carbon nanotubular fibers with a very high nitrogen concentration (approximately 20 at.%) were synthesized through the aerosol-assisted decomposition of dimethylformamide in the presence of catalyst. The synthesized fibers process a novel "pearl necklace-like" morphology and exhibit an excellent field emission performance.
Action of 2',2'-difluorodeoxycytidine on DNA synthesis. (1991)

The action of the new deoxycytidine analogue 2',2'-difluorodeoxycytidine (dFdC) on DNA synthesis was investigated in whole cells and in vitro assay systems with purified DNA polymerases. DNA synthesis in human lymphoblastoid CEM cells was inhibited by dFdC in a concentration-dependent manner that could not be reversed by exogenous deoxynucleosides. The analogue was incorporated into cellular DNA; most of the incorporated dFdC 5'-monophosphate (dFdCMP) residues were in internucleotide linkage. In vitro DNA primer extension assays demonstrated that dFdC 5'-triphosphate (dFdCTP) competed with deoxycytidine triphosphate for incorporation into the C sites of the growing DNA strand. The ratios of the apparent Km values for the incorporation of dFdCTP and dCTP into a C site of M13mp19 DNA were 21.8 and 22.9 for DNA polymerases alpha and epsilon, respectively. The apparent Ki values of dFdCTP were 11.2 microM for DNA polymerase alpha and 14.4 microM for polymerase epsilon. After dFdCMP incorporation, the primer was extended by one deoxynucleotide before a major pause in the polymerization process was observed. This was in contrast to the action of arabinosylcytosine 5'-triphosphate, which caused both DNA polymerases alpha and epsilon to pause at the site of incorporation. The 3'----5' exonuclease activity of DNA polymerase epsilon was essentially unable to excise nucleotides from DNA containing dFdCMP at either the 3'-end or at an internal position, whereas arabinosylcytosine monophosphate was removed from the 3'-terminus at 37% the rate for deoxynucleotides. The cytotoxic activity of dFdC was strongly correlated with the amount of dFdCMP incorporated into cellular DNA. Our results demonstrate qualitative and quantitative differences in the molecular actions of dFdC and arabinosylcytosine on DNA metabolism, but are consistent with an important role for such incorporation in the toxicity of dFdC.
Low resistance ohmic contacts to n-GaN and n-AlGaN using NiAl (2000)

The intermetallic compound NiAl (50:50 at. %) has been shown to be a low-resistance ohmic contact to n-GaN and n-AlGaN. NiAl contacts on n-GaN (n=2.5×1017 cm−3) had a specific contact resistance of 9.4×10−6 Ω cm2 upon annealing at 850 °C for 5 min. NiAl contacts annealed at 900 °C for 5 min in n-Al0.12Ga0.88N (n=2.4×1018 cm−3) and n-Al0.18Ga0.82N (n=2.7×1018 cm−3) had specific contact resistances of 2.1×10−5 Ω cm2 and 4.7×10−5 Ω cm2, respectively. Additionally, these contacts were subjected to long-term annealing at 600 °C for 100 h. On n-GaN, the contact specific contact resistance degraded from 9.4×10−6 Ω cm2 to 5.3×10−5 Ω cm2 after the long-term anneal. Contacts to n-Al0.18Ga0.82N showed only slight degradation with a change in contact resistance, from 4.7×10−5 Ω cm2 to 9.2×10−5 Ω cm2. These results demonstrate the NiAl has great promise as a stable, low-resistance contact, particularly to n-AlGaN used in high-temperature applications.
Computer-based radiology information system: from floppy disk to CD-ROM. (1995)

The authors have developed a comprehensive computer-based radiology information system known as "Radiology Resource and Review" (R3). The content is divided into 10 radiology information categories spanning the entire human body and presently includes more than 4 Mbytes of text, 9,000 topics, and 6,000 images. The R3 software and the information content are stored on compact disk, read-only memory (CD-ROM) media. The images are compressed by using a standard compression algorithm. Images and text are cross-indexed with more than 13,000 key words, which can be linked together in searches by using Boolean logic. Four different retrieval interfaces support browsing of text and image information, diagnosis decision making, self-study, and teaching file preparation. The 10-year university-funded evolution of R3 is an example of the transition in storage media from floppy disk to CD-ROM.
A novel, adaptive system for 3-D optical profilometry using a liquid crystal light projector (1994)

A 3-D optical whole-field profilometer based on adaptive projection of structured light is presented. The system is based on the projection of gratings by means of an LCD unit. The gratings can be varied both in contrast and in period, to adapt to the shape of the object under measurement. A video camera acquires at a different angle the object-deformed pattern. Suitable pre-elaboration is performed, to decrease dependence on background illumination and nonuniform reflectivity of the surface. Adaptive demodulation of the pattern allows the object profile to be evaluated. The performance of the instrument has been evaluated by means of a system calibration against a traceable high-precision commercial Contact Measuring Machine (CMM). The overall accuracy of the system is equal to 0.15 mm with a precision of 0.2 mm. In this article, the theoretical aspects of the technique are discussed, and the description of the complete system is presented. Profile reconstruction, calibration, and certification of the system are also covered. The accuracy of the system is discussed, and experimental results are presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Multicellular Tumor Spheroids Grown from Pancreatic Carcinoma Cell Lines (1997)

Carcinoma of the pancreas is the fifth leading cause of cancer death, with the majority of patients presenting with unresectable disease. Research into new adjuvant therapies is hampered by the lack of suitable in vivo and in vitro models. We have examined the potential of seven pancreatic carcinoma cell lines to grow as multicellular tumor spheroids (MTS). Three of seven (43%) cell lines were scored positive for MTS formation, and the growth characteristics for spheroid models of the cell lines PANC1 and MIAPaCa2 are presented. Implantation of PANC1 MTS into the pancreas of athymic nude mice produces tumors with reproducible growth characteristics and histology.