gebhart/patrepeval huggingface dataset:
Vitamin D Analogs as Modulators of Vitamin D Receptor Action (2003)

The natural calcium-regulating hormone 1alpha,25-dihydroxyvitamin D(3) (1,25D(3)) is a secosteroid that offers organic chemists many sites for modifying structural and/or functional groups. Such modifications alter the chemistry, stereochemistry, and biological properties of the natural hormone. The resulting deltanoids (vitamin D analogs) have been used in the past two decades as molecular probes to investigate structure-function relationships based on their interactions with proteins that regulate deltanoid biostability (catabolic enzymes of the vitamin D endocrine system and vitamin D binding protein) and deltanoid transduction of biological activities (nuclear and membrane receptors). In this review we will focus on structural modifications of 1,25D(3) that selectively modulate the nuclear vitamin D receptor (VDR). We will discuss the structural requirements and modifications that create analogs with greater potency and efficacy than the natural hormone (superagonists). We will also identify the structural features of an emerging group of noncalcemic selective agonists and describe the pharmacokinetic properties and VDR-mediated actions that promote their tissue- and gene-selective responses. In addition, we will speculate on the possible structural requirements for vitamin D antagonists. We will also examine the evidence from studies in cell-free systems, in culture and in vivo that explain the mechanisms for the distinct actions of each group of analogs, with special emphasis on the relationship between their mode of interaction with the VDR and the molecular and cellular outcome of these interactions. Finally, we will describe the current and potential use of these selective modulators of the VDR for treatment of human diseases such as osteoporosis, cancer, and secondary hyperparathyroidism.
Hydrogen Peroxide Stimulates Phospholipase A2-Mediated Arachidonic Acid Release in Cultured Intestinal Epithelial Cells (INT 407) (1991)

The mechanisms by which hydrogen peroxide and, for comparison, 4-beta-phorbol-12-myristate-13-acetate (PMA) stimulate release of radiolabeled arachidonic acid (14C-AA) in cultured intestinal epithelial cells (INT 407) were investigated. Both hydrogen peroxide and PMA caused a rapid (3 min) and dose-related intracellular release of free 14C-AA, followed by a dose- and time-dependent release of 14C-AA into the extracellular medium, but hydrogen peroxide was about 50,000 times less effective than PMA in releasing 14C-AA. No 14C-AA was released on stimulation with 4-alpha-phorbol-12,13-di-decanoate (PDD), a phorbol ester that does not activate protein kinase C. The 14C-AA release was reduced by the phospholipase A2 inhibitors nordihydroguaiaretic acid and 4-bromophenacyl bromide and by the calmodulin/protein kinase C inhibitor trifluoperazine and the protein kinase C inhibitor 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H-7). However, H-7 was less effective than the other inhibitors in reducing the hydrogen peroxide-stimulated 14C-AA release. The hydrogen peroxide-stimulated, but not the PMA-stimulated, rapid (3 min) 14C-AA release was associated with an increased influx of extracellular calcium. Stimulation of the cells with PMA resulted in phosphorylation of a cellular protein of about 32 kDa, whereas no phosphorylation of this protein was detected after stimulation with hydrogen peroxide. Taken together, these findings indicate that (i) both PMA and hydrogen peroxide may stimulate phospholipase A2-mediated AA release from human intestinal epithelial cells; (ii) this stimulation is brought about via protein kinase C and calmodulin-mediated events; (iii) PMA-stimulated 14C-AA release is associated with phosphorylation of a 32-kDa protein, possibly lipocortin, whereas the hydrogen peroxide-stimulated release is not; and (iv) calmodulin is more important for the hydrogen peroxide-stimulated 14C-AA release than is protein kinase C. The possibility that hydrogen peroxide-evoked AA release may contribute to the mucosal abnormality in Crohn's disease is discussed.
3-D simulation analysis of high performance SOI lateral BJT for RF applications (2002)

Summary form only given. In view of the rapid growth of the portable wireless communications market, the development of low-power and low-cost RF device technology is becoming important. The SOI lateral BJT has attracted considerable interest due to its low parasitic capacitance and simplified process. However, in the previous reports (Higaki et al. 1991; Shahidi et al. 1991; Babcock et al, 1996), the maximum f/sub max/ is less than half that of conventional bulk Si counterparts. This is presumably due to the high base-resistance (R/sub b/). In this work, we propose novel and practical SOI lateral BJTs which feature drastically reduced R/sup b/. A maximum operating frequency (f/sub max/) as high as 111 GHz is predicted.
Development and Utilization of Camelid VHH Antibodies from Alpaca for 2,2′,4,4′-Tetrabrominated Diphenyl Ether Detection (2014)

An antibody-based analytical method for the detection of a chemical flame retardant using antibody fragments isolated from an alpaca has been developed. One specific chemical flame retardant congener, 2,2',4,4'-tetrabrominated diphenyl ether (BDE-47), is often the major poly-BDE (PBDE) congener present in human and environmental samples and that which is the most frequently detected. An alpaca was immunized with a surrogate of BDE-47 covalently attached to a carrier protein. The resulting mRNA coding for the variable domain of heavy-chain antibodies (VHH) were isolated, transcribed to cDNA, and cloned into a phagemid vector for phage display library construction. Selection of VHHs recognizing BDE-47 was achieved by panning under carefully modified conditions. The assay sensitivity for detecting BDE-47 was down to the part-per-billion (microgram per liter) level. Cross-reactivity analyses confirmed that this method was highly selective for BDE-47 and selected hydroxylated metabolites. When exposed to elevated temperatures, the camelid VHH antibodies retained more reactivity than a polyclonal antibody developed to the same target analyte. The use of this VHH antibody reagent immobilized onto a Au electrode for impedance biosensing demonstrates the increased versatility of VHH antibodies.
Characterization of two proteolytically derived soluble polypeptides from the neurofilament triplet components NFM and NFH (1989)

We have purified to homogeneity the regions derived by chymotryptic digestion of the ox neurofilament polypeptides NFH and NFM; the regions, called M1 and M2, are thought to form part of the projecting sidearms of mammalian neurofilaments [Chin, Eagles & Maggs (1983) Biochem. J. 215, 239-252]. They were isolated and purified under non-denaturing conditions and showed no tendency to interact with each other in solution. The Mr values obtained by sedimentation are approx. 61,000 for M1 and 42,000 for M2, considerably lower than the values obtained by SDS/polyacrylamide-gel electrophoresis. These Mr values were unchanged in the presence of 6 M-guanidine hydrochloride, suggesting that the regions exist as monomers in solution. Both M1 and M2 are highly phosphorylated, and there is only a slight change in the sedimentation value upon dephosphorylation. Dephosphorylation of M1 with alkaline phosphatase was more than 90% efficient but was never absolute. Dephosphorylation of M2 was complete. Both M1 and M2 bind Ca2+; in the case of M1, this binding is phosphorylation-dependent. M1 also binds cytochrome c, and dephosphorylation affects binding. In similar conditions, neurofilaments bind at least twice their own mass of cytochrome c, owing to their opposite net charges. No interactions were observed between native or dephosphorylated M1 and M2, and intact neurofilaments under a wide variety of conditions. These results are discussed in terms of the possible roles that neurofilament sidearms might play and throw doubt upon their supposed function of rigidly cross-linking neurofilaments together within the axoplasm of neurons.
Comparative evaluation of gap-fill dielectrics in shallow trench isolation for sub-0.25 μm technologies (2002)

The dielectric material used to fill trenches in Shallow Trench Isolation (STI) of transistors, is key to device performance. This paper (a) evaluates the integration of currently available dielectric technologies and (b) designs an optimized process scheme for 0.25 /spl mu/m node and beyond. A detailed study of LPCVD TEOS, SACVD oxide, Hydrogen-Silsesquioxane SOG (HSQ) and ICP (Inductively Coupled) HDP (High Density Plasma) CVD oxide, for STI, is presented for the first time. A novel ICP HDP-CVD process scheme is shown to have the advantages of single step, low thermal budget and high throughput as well as provide good gap-fill, low HF etch rate, low moisture uptake, low shrinkage with annealing, low diode reverse leakage and isolation at 0.3 /spl mu/m spacing.
A 1.8GHz wide-band stacked-cascode CMOS power amplifier for WCDMA applications in 65nm standard CMOS (2011)

A two-stage power amplifier (PA) for WCDMA operation in standard 65-nm CMOS is presented. The power amplifier delivers a saturated output power of 29.4 dBm at a power-added efficiency of 51% operating from a 3.4V supply at 1.8GHz. A two-stage interstage matching network was employed to achieve a high bandwidth of more than 300MHz where the amplifier shows a high PAE of more than 45%. With a WCDMA input signal a maximum linear output power (@ ACLR=-33 dBc) of 25.4 dBm was measured, corresponding to a linear PAE of 37.9% without digital predistortion (DPD). Using DPD, these figures could be improved to 27.9 dBm and 48%.
(Invited) Random Telegraph Noise: From a Device Physicist's Dream to a Designer's Nightmare (2011)

An overview is given on Random Telegraph Noise (RTN) in MOS-based devices. First, the basic properties and physics are briefly outlined, emphasizing the stochastic nature of its main parameters: the capture and emission time constant, while its amplitude is fixed and specific for each trap. Different techniques exist to characterize RTN in MOS devices, either by time or frequency domain measurements. A distinction can also be made between dynamic equilibrium methods like noise spectroscopy or transient measurements, based on a Deep-Level Transient Spectroscopy approach. While single-device based RTN measurements are still of high value, for modern circuit applications, techniques are being developed allowing a fast assessment of RTN in a large number of transistors. The scaling of CMOS technologies to the 32 nm and below raises the issue of variability induced either by random dopant fluctuations or in general, by random charge fluctuations, both spatially and in time. As will be seen, the presence of traps responsible for RTN brings about an additional source of variability which may become dominant in future memories. Finally, it will be shown that RTN is not only a fundamental component of 1/f noise but the same oxide traps are also largely responsible for the Bias Temperature Instability (BTI) in scaled MOSFETs. This leads to a self-consistent model for BTI and a stochastic approach towards the reliability prediction of deep submicron CMOS technologies.
Isolation of wine influenza virus in Oklahoma. (1977)

Three isolations of swine influenca virus were made from 2 swine herds in west-central Oklahoma. Many swine in these herds had signs of respiratory tract disease, and in 1 herd, some affected animals also had diarrhea. Two isolations were made in swine testicle cell line and 1 in embryonating chicken eggs. All 3 strains were cytopathogenic for swine testicle cells.
Brain stem modulation of spatial receptive field properties of single cells in the dorsal lateral geniculate nucleus of the cat (1993)

1. We studied the effect of electrical stimulation of the peribrachial region (PBR) in the brain stem on the visual response of single cells in the dorsal lateral geniculate nucleus (dLGN) to a light slit presented in a series of positions across the receptive field. The response was plotted against slit position, giving a spatial receptive field profile. 2. PBR stimulation markedly increased the visual response. In the middle of the receptive field center, the absolute response increase was considerably larger than in the peripheral parts of the receptive field or than the increase of spontaneous activity. The PBR stimulation also led to a small increase of the diameter of the receptive field center. 3. The maximum steepness of the receptive field profile for the dLGN cells increased by PBR stimulation. We suggest that the visual resolution in the dLGN cell is directly related to this maximal slope of the receptive field profile rather than to the width of the receptive field center. This would mean that increased input from the PBR, as presumably occurs during arousal, increases the visual resolution of the dLGN cells. 4. For some of the cells we could record S-potentials (slow potentials) in addition to action potentials. This allowed us to directly compared the receptive field center size of a dLGN cell with that of its retinal input. For these cells, the center size was considerably reduced by the geniculate relay. During PBR stimulation, the center size of these cells also increased slightly, but even in this condition it was reduced compared with the retinal input. The maximal slope of the receptive field profile in the dLGN cell during PBR stimulation was larger than for the retinal input. 5. We also examined the effect of ionophoretical application of acetylcholine (ACh) and bicuculline methchloride (BMC) on the spatial receptive field properties of dLGN cells. The effects of ACh were similar to those of PBR stimulation. Application of BMC, on the other hand, made the receptive field profile more similar to that of retinal ganglion cells.
Deficits in Trace Fear Memory and Long-Term Potentiation in a Mouse Model for Fragile X Syndrome (2005)

Trace fear memory requires the activity of the anterior cingulate cortex (ACC) and is sensitive to attention-distracting stimuli. Fragile X syndrome is the most common form of mental retardation with many patients exhibiting attention deficits. Previous studies in fragile X mental retardation 1 (FMR1) knock-out (KO) mice, a mouse model for fragile X, focused mainly on hippocampal-dependent plasticity and spatial memory. We demonstrate that FMR1 knock-out mice show a defect in trace fear memory without changes in locomotion, anxiety, and pain sensitivity. Whole-cell path-clamp recordings in the ACC show that long-term potentiation (LTP) was completely abolished. A similar decrease in LTP was found in the lateral amygdala, another structure implicated in fear memory. No significant changes were found in basal synaptic transmission. This suggests that synaptic plasticity in the ACC and amygdala of FMR1 KO mice plays an important role in the expression of behavioral phenotypes similar to the symptoms of fragile X syndrome.
β‐enolase deficiency, a new metabolic myopathy of distal glycolysis (2001)

A severe muscle enolase deficiency, with 5% of residual activity, was detected in a 47-year-old man affected with exercise intolerance and myalgias. No rise of serum lactate was observed with the ischemic forearm exercise. Ultrastructural analysis showed focal sarcoplasmic accumulation of glycogen beta particles. The enzyme enolase catalyzes the interconversion of 2-phosphoglycerate and phosphoenolpyruvate. In adult human muscle, over 90% of enolase activity is accounted for by the beta-enolase subunit, the protein product of the ENO3 gene. The beta-enolase protein was dramatically reduced in the muscle of our patient, by both immunohistochemistry and immunoblotting, while alpha-enolase was normally represented. The ENO3 gene of our patient carries two heterozygous missense mutations affecting highly conserved amino acid residues; a G467A transition changing a glycine residue at position 156 to aspartate, in close proximity to the catalytic site, and a G1121A transition changing a glycine to glutamate at position 374. These mutations were probably inherited as autosomal recessive traits since the mother was heterozygous for the G467A and a sister was heterozygous for the G1121A transition. Our data suggest that ENO3 mutations result in decreased stability of mutant beta-enolase. Muscle beta-enolase deficiency should be considered in the differential diagnosis of metabolic myopathies due to inherited defects of distal glycolysis.
Gigabit wireless LANs (2011)

This paper gives an overview of the upcoming IEEE Gigabit Wireless LAN amendments, i.e. IEEE 802.11ac and 802.11ad. Both standard amendments advance wireless networking throughput beyond gigabit rates. 802.11ac adds multi-user access techniques in the form of downlink multi-user (DL MU) multiple input multiple output (MIMO)and 80 and 160 MHz channels in the 5 GHz band for applications such as multiple simultaneous video streams throughout the home. 802.11ad takes advantage of the large swath of available spectrum in the 60 GHz band and defines protocols to enable throughput intensive applications such as wireless I/O or uncompressed video. New waveforms for 60 GHz include single carrier and orthogonal frequency division multiplex (OFDM). Enhancements beyond the new 60 GHz PHY include Personal Basic Service Set (PBSS) operation, directional medium access, and beamforming. We describe 802.11ac channelization, PHY design, MAC modifications, and DL MU MIMO. For 802.11ad, the new PHY layer, MAC enhancements, and beamforming are presented.
Birth of Mice after Transplantation of Early Cell-Cycle-Stage Embryonic Nuclei into Enucleated Oocytes1 (1993)

The present study was conducted to investigate the influence of cell cycle stage of the donor nucleus on chromatin structure and development of mouse embryonic nuclei transplanted into enucleated oocytes. Donor cell-cycle stage was controlled in order to examine, in addition, the developmental potential of nuclei from 2-, 4-, and 8-cell-stage embryos. The cell cycle stage of donor nuclei was classified as early, middle, or late. After nuclear transfer, electrofusion, and activation, early-stage transplants formed a single pronucleus-like structure, but middle-stage transplants formed very irregular types of structures and late-stage transplants extruded a polar body. A high proportion of development to the blastocyst stage (77.8%) and an increased cell number (62.1 cells) were obtained from the early 2-cell-stage transplants as opposed to the middle- (0%) and late-stage (20.8%, 37.0 cells) transplants (p < 0.001). With transplantation of early-stage nuclei, high proportions of development to the blastocyst stage and of offspring were obtained from nuclear transplant embryos with a nucleus from a 2-, 4-, or 8-cell-stage embryo. The results confirm that the donor cell-cycle stage critically affects the chromatin structure and development of nuclear transplant embryos. The results also demonstrate that the nuclei from 2-, 4-, and 8-cell-stage mouse embryos in the early stage of each cell cycle can be reprogrammed when transplanted into enucleated mature oocytes.
Anisotropy in magnetic properties and electronic structure of single-crystalLiFePO4 (2008)

We report the experimental and theoretical results on the anisotropies in the magnetic properties and x-ray absorption spectra of single-crystal $\mathrm{Li}\mathrm{Fe}\mathrm{P}{\mathrm{O}}_{4}$. A mean-field theory is developed to explain the observed strong anisotropies in Lande $g$-factor, paramagnetic Curie temperature, and effective moment for $\mathrm{Li}\mathrm{Fe}\mathrm{P}{\mathrm{O}}_{4}$ single crystals. The values of the in-plane nearest- and next-nearest-neighbor spin exchange (${J}_{1}$ and ${J}_{2}$), interplane spin exchange $({J}_{\ensuremath{\perp}})$, and single-ion anisotropy $(D)$, obtained recently from neutron scattering measurements, are used for calculating the Curie temperatures with the formulas derived from the mean-field Hamiltonian. It is found that the calculated Curie temperatures match well with that obtained by fitting the magnetic susceptibility curves to the modified Curie-Weiss law. For the polarized $\mathrm{Fe}\phantom{\rule{0.2em}{0ex}}K$-edge x-ray absorption spectra of single-crystal $\mathrm{Li}\mathrm{Fe}\mathrm{P}{\mathrm{O}}_{4}$, a different feature assignment for the $1s\ensuremath{\rightarrow}4p$ transition features is proposed and the anisotropy in the intensities of the $1s\ensuremath{\rightarrow}3d$ transition features is explained adequately by a one-electron theory calculation of the electric quadrupole transition terms in the absorption coefficient.
A Facile Synthesis of 2,4-Dialkoxy-, 2-Alkoxy-4-phenoxy- and 2,4-Diphenoxy-6-trifluoromethyl-3,4-dihydro-2H-pyrans. Hetero-Diels-Alder Reactions oftrans-β-Trifluoroacetylvinyl Ethers with Various Vinyl Ethers (1989)

2,4-Dialkoxy-, 2-alkoxy-4-phenoxy-, and 2,4-diphenoxy-6-trifluoromethyl-3,4-dihydro-2H-pyrans are obtained in high yields by the hetero-Diels Alder reaction of trans-β-trifluoroacetylvinyl ethers with various vinyl ethers under mild conditions.
A CD36-initiated Signaling Cascade Mediates Inflammatory Effects of β-Amyloid (2002)

beta-Amyloid accumulation is associated with pathologic changes in the brain in Alzheimer's disease and has recently been identified in plaques of another chronic inflammatory disorder, atherosclerosis. The class B scavenger receptor, CD36, mediates binding of fibrillar beta-amyloid to cells of the monocyte/macrophage lineage, including brain macrophages (microglia). In this study, we demonstrate that in microglia and other tissue macrophages, beta-amyloid initiates a CD36-dependent signaling cascade involving the Src kinase family members, Lyn and Fyn, and the mitogen-activated protein kinase, p44/42. Interruption of this signaling cascade, through targeted disruption of Src kinases downstream of CD36, inhibits macrophage inflammatory responses to beta-amyloid, including reactive oxygen and chemokine production, and results in decreased recruitment of microglia to sites of amyloid deposition in vivo. The finding that engagement of CD36 by beta-amyloid initiates a Src kinase-dependent production of inflammatory mediators in cells of the macrophage lineage reveals a novel receptor-mediated pro-inflammatory signaling pathway of potential therapeutic importance.