gebhart/patrepeval huggingface dataset:
Changing a Single Amino Acid Residue Switches Processive and Non-processive Behavior of Aspergillus nigerEndopolygalacturonase I and II (2001)

Processivity, also known as multiple attack on a single chain, is a feature commonly encountered only in enzymes in which the substrate binds in a tunnel. However, of the seven Aspergillus niger endopolygalacturonases, which have an open substrate binding cleft, four enzymes show processive behavior, whereas the other endopolygalacturonases are randomly acting enzymes. In a previous study (Benen, J.A.E., Kester, H.C.M., and Visser, J. (1999) Eur. J. Biochem. 259, 577-585) we proposed that the high affinity for the substrate of subsite -5 of processive endopolygalacturonase I constitutes the origin of the multiple attack behavior. Based on primary sequence alignments of A. niger endopolygalacturonases and three-dimensional structure analysis of endopolygalacturonase II, an arginine residue was identified in the processive enzymes at a position commensurate with subsite -5, whereas a serine residue was present at this position in the non-processive enzymes. In endopolygalacturonase I mutation R95S was introduced, and in endopolygalacturonase II mutation S91R was introduced. Product progression analysis on polymer substrate and bond cleavage frequency studies using oligogalacturonides of defined chain length for the mutant enzymes revealed that processive/non-processive behavior is indeed interchangeable by one single amino acid substitution at subsite -5, Arg-->Ser or Ser-->Arg.
Effect of carbimazole treatment on specific and non-specific immunological parameters in patients with Graves' disease. (1984)

Twenty-two patients with newly diagnosed Graves' disease (GD) were treated with carbimazole (CBZ) for 6 months. Thyroid stimulating immunoglobulins (TSI) and T cell subsets were studied prior to treatment and after 3 and 6 months of therapy. TSI were measured on human thyroid epithelial cell monolayers by the cAMP production after the addition of highly purified GD IgG. Before treatment, serum IgG from 20 out of the 22 patients (91%) stimulated cAMP production significantly compared to normal IgG. The mean index of cAMP production (GD IgG relative to normal IgG) was 2.15. After 3 months of CBZ treatment, a non-significant decrease of the mean cAMP production index was observed, whereas it was significantly decreased at the end of the 6 month course of therapy. Before treatment, total T cells (OKT3+), helper/inducer T cells (OKT4+) and suppressor/cytotoxic T cells (OKT8+) were all significantly decreased compared with controls. After 3 or 6 months of CBZ therapy, both total T cells and helper/inducer T cells returned to a normal level, while cytotoxic/suppressor T cells remained at the same low level. Taken together, these data indicate that treatment with CBZ leads to an early increase of helper/inducer T cells followed 3 months later by a decrease of the TSI level with no change in decreased suppressor/cytotoxic T cells. The disappearance of TSI following the increased helper/inducer T cell level suggests that an anti-idiotypic reaction may have occurred, and the persistent decrease of the suppressor/cytotoxic T subset that CBZ therapy does not act upon the underlying autoimmune disease.
Fungal morphogenesis and virulence (2000)

Phenotypic variability in pathogenic fungi has long been correlated with virulence, but specific genetic and molecular mechanisms are only recently being unraveled. Fungal morphogenesis, reflecting the expression of several regulated genes, and the capacity of the rising forms or phases to cause disease has been focused on at the XIVth Congress of the International Society for Human and Animal Mycology. Three experimental models of pathogenic fungi have been discussed. In Cryptococcus neoformans, phenotypic variability or switching represents controlled and programmed changes rather than random mutations. Evaluated phenotypic traits were the capsular polysaccharide, cell and colony morphology and virulence. In the dimorphic Paracoccidioides brasiliensis, the serine-thiol proteinase from the yeast phase cleaves the main components of the basal membrane, thus being potentially relevant in fungal dissemination. In Candida albicans, relationships between adhesion proteins and those of lymphocytes and neutrophils are related to fungal pathogenicity. Regulation of the directional growth of hyphae and its tropic responses are correlated with the invasive potential of C. albicans.
Electroluminescence of violanthrone obtained by vacuum-deposition of 3,3'-dibenzanthronyl. (1994)

A novel doped EL device was fabricated utilizing thermal ring closure reaction of 3,3'-dibenzanthronyl (1) in the vacuum deposition process. By controlling deposition temperature of (1), part of (1) reacted to violanthrone (2) to give a thin film of compound (1) doped with (2). Red emission of (2) was observed from the EL cell consisted of ITO / TPD / (1) doped with (2) / Al.
tRNA Is the Source of Low-Level <i>trans-</i> Zeatin Production in <i>Methylobacterium</i> spp (2002)

Pink-pigmented facultatively methylotrophic bacteria (PPFMs), classified as Methylobacterium spp., are persistent colonizers of plant leaf surfaces. Reports of PPFM-plant dialogue led us to examine cytokinin production by PPFMs. Using immunoaffinity and high-performance liquid chromatography (HPLC) purification, we obtained 22 to 111 ng of trans-zeatin per liter from culture filtrates of four PPFM leaf isolates (from Arabidopsis, barley, maize, and soybean) and of a Methylobacterium extorquens type culture originally recovered as a soil isolate. We identified the zeatin isolated as the trans isomer by HPLC and by a radioimmunoassay in which monoclonal antibodies specific for trans-hydroxylated cytokinins were used. Smaller and variable amounts of trans-zeatin riboside were also recovered. trans-Zeatin was recovered from tRNA hydrolysates in addition to the culture filtrates, suggesting that secreted trans-zeatin resulted from tRNA turnover rather than from de novo synthesis. The product of the miaA gene is responsible for isopentenylation of a specific adenine in some tRNAs. To confirm that the secreted zeatin originated from tRNA, we mutated the miaA gene of M. extorquens by single exchange of an internal miaA fragment into the chromosomal gene. Mutant exconjugants, confirmed by PCR, did not contain zeatin in their tRNAs and did not secrete zeatin into the medium, findings which are consistent with the hypothesis that all zeatin is tRNA derived rather than synthesized de novo. In germination studies performed with heat-treated soybean seeds, cytokinin-null (miaA) mutants stimulated germination as well as wild-type bacteria. While cytokinin production may play a role in the plant-PPFM interaction, it is not responsible for stimulation of germination by PPFMs.
On the minimal realization of the gyrator by means of nullors and resistors (1975)

Abstract This paper is a second step in the proof of the conjecture that it is impossible to synthesize a gyrator by means of nullors and linear resistors with fewer than four resistors if only two nullors are permitted, or with fewer than three nullors if only two resistors are permitted. It is proved that a gyrator cannot be realized with only two nullors and two resistors. In a forthcoming paper (third step) it will be proved that a two‐nullor, three‐resistor gyrator realization cannot be obtained. The proofs are presented in such a way that at the same time a synthesis procedure for minimal nullor‐resistor networks is demonstrated.
[Hepatitis G virus or hepatitis GB virus C]. (1999)

In 1995 two novel human virae were identified independently, GB virus C and hepatitis G virus, as possible etiological agents for non-A-E viral hepatitis. GBV-C and HGV are two isolates of the same virus. GBV-C/HGV is an RNA virus of app. 9 kb belonging to the Flaviviridae family. GBV-C/HGV is transmitted intravenously, sexually and vertically from mother to child. GBV-C/HGV can be detected in blood by RT-PCR and serological tests based on the envelope 2 protein. Infection by GBV-C/HGV is frequent and 1-10% of blood donors in Western countries have been found positive by PCR. Acute GBV-C/HGV infections are in some cases associated with mild hepatitis. About 10-20% of the infections become chronically persistent but are not associated with chronic hepatitis or other known disease. GBV-C/HGV is not found in hepatocytes and is not infectious in the chimpanzee model, therefore GBV-C/HGV is not a classical hepatitis virus. Detection of GBV-C/HGV by PCR may be indicated in the diagnosis of acute hepatitis.
Muscle afferent activity modulates bioassayable growth hormone in human plasma (2000)

Immunoassayable and bioassayable growth hormone responses to vibration-induced activation of muscle spindle afferents of the soleus (Sol) or tibialis anterior (TA) muscles were studied in 10 men. Subjects were supine while a 10-min vibration stimulus (100 Hz; 1.5-mm amplitude) was applied to the muscle, with each of the muscles tested on separate days. Blood samples were collected before, during, immediately after, and after 5 and 10 min of vibration. Plasma growth hormone concentrations were determined by radioimmunoassay (IGH) for all sampling periods and by bioassay (BGH; measurement of tibial epiphysial cartilage growth in hypophysectomized rats) for samples obtained before and immediately after vibration. Plasma IGH concentrations were similar at all time points during the Sol or TA experiments. After 10 min of muscle vibration, mean plasma BGH was elevated 94% [1,216 +/- 148 (SD) to 2, 362 +/- 487 microg/l; P = 0.0001] for TA and decreased 22% (1,358 +/- 155 to 1,058 +/- 311 microg/l; P = 0.09) for Sol. These data demonstrate that activation of TA muscle spindle afferents increases circulating BGH but not IGH. The absence of a similar vibration-induced BGH response for the Sol indicates a differential regulation of BGH release by these two predominantly slow muscles, perhaps related to their respective flexor and extensor functions. These data indicate that a muscle afferent-pituitary axis modulates the release of BGH, but not IGH, from the pituitary in humans and that this axis is muscle specific, similar to that observed in rats.
A high flux pulsed source of energetic atomic oxygen (1986)

The design and demonstration of a pulsed high flux source of nearly monoenergetic atomic oxygen are reported. In the present test setup, molecular oxygen under several atmospheres of pressure is introduced into an evacuated supersonic expansion nozzle through a pulsed molecular beam valve. A 10J CO2 TEA laser is focused to intensities greater than 10 to the 9th W/sq cm in the nozzle throat, generating a laser-induced breakdown with a resulting 20,000-K plasma. Plasma expansion is confined by the nozzle geometry to promote rapid electron-ion recombination. Average O-atom beam velocities from 5-13 km/s at fluxes up to 10 to the 18th atoms/pulse are measured, and a similar surface oxygen enrichment in polyethylene samples to that obtained on the STS-8 mission is found.
The Formation of Higher Alcohols in the Fermentation of Amino Acids by Yeast (1961)

We have found that some straight-chained α-amino acids are converted by yeast to the alcohols with correspondingly longer carbon chains in the alcoholic fermentation contrary to F. Ehrlich's scheme, i. e., isobutyl alcohol from alanine and active amyl alcohol from α-amino-n-butyric acid or threonine.In this report, we confirmed this fact in the alcoholic fermentation of many aliphatic amino acids by 2 yeast strains using gas chromatography. Moreover, n-propyl alcohol was proved to come from α-amino-n-butyric acid or threonine. Small quantities of n-propyl, isobutyl, active amyl and isoamyl alcohols were found in all the fermented solutions. There was some difference in the composition of higher alcohols of the alcoholic solutions fermented by different yeasts.
OPTICAL MIXING IN CADMIUM TELLURIDE USING THE PULSED WATER VAPOR LASER (1970)

We report here the first observation of second harmonic generation and sum frequency mixing with fundamental wavelengths in the 26 to 33μ range, using the pulsed water vapor laser and CdTe as a nonlinear material. We obtain an approximate value of d36(λ1 = 27.97μ)=(9 ± 6) × 10−7 esu in CdTe, about twice as large as the value at 10.6μ, which we discuss in terms of Garrett's model of the dispersion of d36.
Quantitative analysis of in vivo high-resolution microendoscopic images for the detection of neoplastic colorectal polyps (2018)

Colonoscopy is routinely performed for colorectal cancer screening but lacks the capability to accurately characterize precursor lesions and early cancers. High-resolution microendoscopy (HRME) is a low-cost imaging tool to visualize colorectal polyps with subcellular resolution. We present a computer-aided algorithm to evaluate HRME images of colorectal polyps and classify neoplastic from benign lesions. Using histopathology as the gold standard, clinically relevant features based on luminal morphology and texture are quantified to build the classification algorithm. We demonstrate that adenomatous polyps can be identified with a sensitivity and specificity of 100% and 80% using a two-feature linear discriminant model in a pilot test set. The classification algorithm presented here offers an objective framework to detect adenomatous lesions in the colon with high accuracy and can potentially improve real-time assessment of colorectal polyps.
Cytochrome P450 1A2 (CYP1A2) activity and risk factors for breast cancer: a cross-sectional study (2004)

These results suggest that CYP1A2 activity is correlated with hormones, blood lipids, and lifestyle factors associated with breast cancer risk, although some of the observed associations were contrary to hypothesized directions and suggest that increased CYP1A2 function may be associated with increased risk for breast cancer.
Development of a Fibre-Optic DOAS Sensor for the Detection of Exhaust Gases Using Ratiometric Separation Techniques (2007)

A fibre-optic sensor based on differential optical absorption spectroscopy was developed to operate within exhaust environments and to monitor several exhaust gases. Cross sensitivity issues between each of the gases in the UV region were realised and ratiometric separation techniques were developed reduce the sensor's susceptibility to these interferences. Experimental results describing the calibration of the sensor against a commercial analyser and tests documenting the sensor's operating capabilities within the exhaust of an engine are presented.
Optical implementation of the fractional Hilbert transform for two-dimensional objects (1997)

The classical Hilbert transform can be implemented optically as a spatial-filtering process, whereby half the Fourier spectrum is pi-phase shifted. Recently the Hilbert transform was generalized. The generalized version, called the fractional Hilbert transform, is quite easy to implement optically if the input is one dimensional. Here we show how to implement the fractional Hilbert transform for two-dimensional inputs. Hence the new transform is now suitable for image processing.
Changes in the protein pattern of H1 histones associated with apoptotic DNA fragmentation (1999)

Characteristic steps in the course of cellular apoptosis are the induction of chromatin condensation and cleavage of the DNA, leading to the formation of oligomers of nucleosomes. Since the H1 histones represent functional elements that are essential for the generation of highly condensed chromatin structures, we analysed the total cellular H1 histones of five leukaemic and three solid human tumour cell lines, comparing the H1 pattern of exponentially growing cells with that of apoptotic cells. For the induction of apoptosis, cell lines were treated with the water-soluble camptothecin derivative, topotecan (a topoisomerase I inhibitor), or with an apoptosis-inducing monoclonal anti-CD95 (Fas/APO-1) antibody. Total histone H1 proteins were isolated by extraction with 5% perchloric acid and were analysed by means of capillary zone electrophoresis (CZE) separation. The identities of the peaks representing different histone H1 subtypes on CZE electropherograms were confirmed by analysis of preparations (recombinant proteins purified from transformed yeast used as internal standards) mixed with each of the subtypes respectively. The progress of topotecan- or anti-CD95-induced cell death was monitored by flow cytometry analysis and also by agarose electrophoresis of fragmented DNA. During early apoptosis of three of these cell lines, we observed the induction of internucleosomal DNA cleavage and, simultaneously, a typical change in the histone H1 protein pattern, leading to an increase in the relative amounts of histone subtypes H1.4 and H1.5. Upon apoptosis induction, these changes were only observed in correlation with the occurrence of DNA fragmentation, thus possibly reflecting a prerequisite for DNA accessibility and/or endonuclease activity.
Space-charge-limited bipolar currents in polymer/C60 diodes (2002)

We investigate carrier’s transport for devices formed by a heterojunction of the substituted polythiophene polymer and the C60 molecule, sandwiched between anode of indium-tin oxide/poly(3,4-ethylene dioxythiophene) and cathode of Al, for different thicknesses of the C60. We measure their current-voltage characteristics and find that the forward current is limited by spatial charge of holes in the polymer layer and electrons in the molecule layer. We also find that the effective mobilities of holes in the polymer and of electrons in the C60 are dependent on the different thickness of the layers. By adapting to our systems an electrical analytic model previously used in the literature to study bilayer organic diodes, we are able to explain the experimental results.
CO 2 Decomposition Characteristics of Zn-ferrite Powder Prepared by Hydrothermal and Solid State Reaction (2011)

The objective of this study is the development of carbon recycle technology which converts captured from flue gas to CO or carbon and reuse in industrial fields. Since is very stable and difficult to decompose, metal oxide was used as an activation agent for the decomposition of at low temperature. Metal oxides which convert to CO or carbon at were prepared using Zn-ferrite by the solid state reaction and hydrothermal synthesis. The behaviors of decomposition were studied using temperature programmed reduction/oxidation (TPR/TPO) and thermogravimetric analyzer (TGA). Zn-ferrite containing 5 wt% ZnO showed the largest reduction and oxidation. Reduction by was 26.53 wt%, oxidation by was 25.73 wt% and 96.98% of adsorbed was decomposed to and carbon with excellent oxidation-reduction behaviors.
ChemInform Abstract: Heterodiene and Heteroene Activity of Benzoyl Isothiocyanates Towards Electronrich Alkynes. (1986)

Abstract The propyne (I) reacts with the isothiocyanates (II) to give the oxazines (III)‐(V).
Low-cost solar adaptive optics in the infrared (2003)

We have developed a low-cost adaptive optics system for solar observations in the infrared between 1 and 28 μm with the 1.5-m McMath-Pierce solar telescope. The 37-actuator membrane mirror and a fast tip-tilt mirror are controlled by a PC running Linux RedHat 7.1 that analyzes images from a 256 by 256 pixel, 1 kHz frame rate CCD camera. The total hardware cost is less than $25,000, and the system provides diffraction-limited performance under median seeing conditions above 2.3 μm. The single Pentium III processor provides enough computing power to analyze the 200 subapertures of the Shack-Hartmann wavefront sensor in real time. We describe the hardware and software implementations and show results from the first tests at the telescope.
Arachidonic acid metabolism in polymorphonuclear leukocytes (1979)

Addition of arachidonic acid and the divalent cation ionophore A23187 to a suspension of human peripheral blood polymorphonuclear leukocytes led to the formation of (5S)-hydroxy-6,8,11,14-icosatetraenoic acid, (15S)-hydroxy-5,8,11,13-icosatetraenoic acid, and (5S,12R)-dihydroxy-6,8,10,14-icosatetraenoic acid. A method based on high-pressure liquid chromatography has been developed for assay of these metabolites. The addition of arachidonic acid to human polymorphonuclear leukocytes always resulted in formation of the isomeric monohydroxy acids. However, cells prepared from blood of different subjects were found to vary with respect to formation of the 5,12-dihydroxy acid. Addition of the ionophore alone strongly stimulated the formation of the 5-monohydroxy acid and more specifically the 5,12-dihydroxy acid from endogenous arachidonic acid. In all experiments performed the formation of the 5-hydroxy acid and the 5,12-dihydroxy acid was maximally stimulated when both arachidonic acid and the ionophore were added to the incubation mixture. Under these conditions, stimulation of 40-fold or more of the formation of both compounds was observed. The data demonstrate that, in addition to causing release of endogenous substrate, the ionophore also activated the enzymatic system involved in the further transformations of arachidonic acid. This finding raises the possibility that this pathway of arachidonic acid metabolism is involved in the biological response (e.g., release of lysosomal enzymes, the slow reacting substance of anaphylaxis, and chemotactic factors) of leukocytes to A23187 and other stimuli.
Laboratory Evolution of Escherichia coli Thioredoxin for Enhanced Catalysis of Protein Oxidation in the Periplasm Reveals a Phylogenetically Conserved Substrate Specificity Determinant (2007)

Thioredoxin exported into the Escherichia coli periplasm catalyzes the oxidation of protein thiols in a DsbB-dependent function. However, the oxidative activity of periplasmic thioredoxin is insufficient to render dsbA(-) cells susceptible to infection by M13, a phenotype that is critically dependent on disulfide bond formation in the cell envelope. We sought to examine the molecular determinants that are required in order to convert thioredoxin from a reductant into an efficient periplasmic oxidant. A genetic screen for mutations in thioredoxin that render dsbA(-) cells sensitive to infection by M13 led to the isolation of a single amino acid substitution, G74S. In vivo the TrxA(G74S) mutant exhibited enhanced catalytic activity in the oxidation of alkaline phosphatase but was unable to oxidize FlgI and restore cell motility. In vitro studies revealed that the G74S substitution does not affect the redox potential of the thioredoxin-active site or its kinetics of oxidation by DsbB. Thus, the gain of function afforded by G74S stems in part from its altered substrate specificity, which also rendered the protein more resistant to reduction by DsbD/DsbC in the periplasm.
Silicone Gel Breast Implants (1994)

ABSTRACT To Editor. —In their Commentary,1 Dr Kessler and colleagues lament the uncertainty and unease that patients are experiencing without acknowledging Food and Drug Administration's (FDA's) significant contribution to this incertitude. The FDA's risk-benefit deliberations have consistently dwelt on safety issues while undervaluing benefits of implants. For example, their Commentary selectively cited two anecdotal clinical studies without adequate controls and a study in rats that used a physically altered gel form not seen in vivo. Recent, much more meaningful epidemiologic studies showing no increase in autoimmune disease2,3 were ignored. Despite efforts of many investigators, no good evidence yet exists supporting a causal relationship between implants and any known medical disease.The FDA publications have consistently accentuated negative while refusing to add reassurance for apprehensive patients where appropriate. This is exemplified in their literature on breast cancer and breast-feeding, which raises concern that language