gebhart/patrepeval huggingface dataset:
Molecular cloning and functional expression in yeast of CYP76B1, a xenobiotic‐inducible 7‐ethoxycoumarin O‐de‐ethylase from Helianthus tuberosus (1998)

In order to obtain plant markers of chemical stress and possible tools for the bio-monitoring of pollution, a protein purification/PCR approach was used to isolate cDNAs of xenobiotic-inducible P450 oxygenases. O-dealkylation of 7-ethoxycoumarin is catalysed in Helianthus tuberosus by cytochromes P450 strongly inducible by a wide range of xenobiotics. Therefore, a 7-ethoxycoumarin O-de-ethylase (ECOD) was purified from induced tuber tissues (Batard et al., 1995). A primer designed from an internal peptide sequence, but also corresponding to a conserved P450 haem-binding region, led to the generation of a gene-specific probe corresponding to a P450 strongly inducible by aminopyrine. Two partial and 98% identical coding sequences were isolated from a cDNA library prepared from aminopyrine-induced tuber. A full-length cDNA was reconstituted by 5'-RACE elongation. The protein deduced from this full-length sequence, with 41.1% amino acid identity to CYP76A1 and high phylogenetic relationship to other CYP76s, was termed CYP76B1. CYP76B1 was expressed in yeast. Microsomes from the transformed yeast catalysed the NADPH-dependent O-dealkylation of 7-ethoxycoumarin. However, protein sequence as well as enzymological data indicated that CYP76B1 does not correspond to the purified ECOD protein. These results confirm previous data and demonstrate that several P450s in H. tuberosus are capable of actively catalysing the O-de-ethylation of ethoxycoumarin. Determination of the steady-state level of CYP76B1 transcripts after slicing tuber tissues and ageing them in water, alone or in the presence of various chemicals, showed that the expression of this P450 was not responsive to mechanical stress, but was strongly induced by chemical treatments. CYP76B1 thus appears to be a good potential marker of chemical stress and of environmental pollution.
Methyl 2-Benzoylamino-3-dimethylaminopropenoate in the Synthesis of Heterocyclic Systems. The Synthesis of Substituted 3-Benzoylamino-2H-pyran-2-ones (1990)

5,6-Disubstituted 3-benzoylamino-2H-pyran-2-ones 3 are prepared either from 1,3-dicarbonyl compounds 1 and methyl 2-benzoyl-amino-3-dimethylaminopropenoate (2) in an one-step reaction, or from ethyl 2-acyl-3-dimethylaminopropenoates 5a,b or 2-(dimethylamino)methylene-1,3-diketones 5c,d and 5-oxo-2-phenyl-1,3-oxazole 6.
Contact Conductivity Detection in Poly(methyl methacylate)-Based Microfluidic Devices for Analysis of Mono- and Polyanionic Molecules (2002)

An on-column contact conductivity detector was developed for the analysis of various mono- and polyanionic compounds separated by electrophoresis chips fabricated in poly(methyl methacrylate) (PMMA) using hot embossing techniques from Ni electroforms. The detector consisted of a pair of Pt wires (127 μm diameter) with an end-to-end spacing of approximately 20 μm and situated within the fluidic channel. The waveform applied to the electrode pair was a bipolar pulse with a frequency of 5.0 kHz and was used to reduce the charging current from measurement so that the current recorded at the end of one pulse is more representative of the solution conductivity. Using the detector, separations of amino acids, peptides, proteins, and oligonucleotides were demonstrated. For the amino acids and peptides, free-solution zone electrophoresis was performed. A calibration plot for the amino acid alanine was found to be linear from approximately 10 to 100 nM in a carrier electrolyte consisting of 10 mM triethylamonium acetate. The concentration detection limit was found to be 8.0 nM, with the corresponding mass detection limit equal to 3.4 amol (injection volume = 425 pL). The protein separations with conductivity detection were performed using MEKC, in which the carrier electrolyte contained the anionic surfactant sodium dodecyl sulfate (SDS) above its cmc. Near baseline resolution was achieved in the PMMA microchip for a solution containing 8 different proteins. In the case of the DNA fragments, capillary electrochromatography was used with a C18-modified PMMA chip and a carrier electrolyte containing an ion-pairing agent.
In vitro assembly of virus-like particles with Rous sarcoma virus Gag deletion mutants: identification of the p10 domain as a morphological determinant in the formation of spherical particles (1997)

Retroviruses are unusual in that expression of a single protein, Gag, leads to budding of virus-like particles into the extracellular space. We have developed conditions under which virus-like particles are formed spontaneously in vitro from fragments of Rous sarcoma virus (RSV) Gag protein purified after expression in Escherichia coli. The CA-NC fragment of Gag was shown previously to assemble into hollow cylinders (S. Campbell and V. M. Vogt, J. Virol. 69:6487-6497, 1995). We have now extended these studies to larger Gag proteins. In every case examined, assembly into regular structures required RNA. A nearly full-length Gag missing only the C-terminal PR domain, as well as similar proteins missing in addition the N-terminal half of MA, the C-terminal half of MA, the entire MA sequence, or the entire p2 sequence, all assembled into spherical particles resembling RSV in size. By contrast, proteins missing p10 assembled into cylindrical particles like those formed by CA-NC alone. Thin section electron microscopy showed that each of these Gag proteins formed in the expressing E. coli cells particles similar in shape to those seen in vitro. We conclude from these results that neither the sequences required for membrane binding in vivo, near the N terminus of Gag, nor the sequences required for a late step in budding, in the p2 portion of Gag, are essential for formation of virus-like particles in this system. Furthermore, we postulate the existence of a shape-determining sequence in p10, which provides or facilitates interactions required for the growing particle to be constrained to a spherical shape.
Mode of action and properties of the β‐xylosidases from Talaromyces emersonii and Trichoderma reesei (2006)

Enzymatic hydrolysis of arabinoxylan is an important prerequisite for the utilization of hemicellulose for ethanol fermentation or for making the low calorie sweetener xylitol by catalytic hydrogenation of the generated xylose. This study focus on cloning and characterization of two industrial relevant beta-xylosidases (1,4-beta-D-xylan xylohydrolase, EC 3.2.1.37) from Talaromyces emersonii (betaXTE) and Trichoderma reesei (betaXTR) and a comparison of these in relation to hemicellulose hydrolysis using an industrial relevant substrate. Both beta-xylosidases were expressed in A. oryzae and subsequently purified. During the enzymatic hydrolysis of xylobiose, the reaction product of both enzymes was found to be beta-D-xylose proving that the hydrolysis is proceeding via a retaining reaction mechanism. Based on sequence similarities and glycosyl hydrolases family membership, the active site residues of betaXTE and betaXTR are predicted to be Asp 242 and Glu 441, and Asp 264 and Glu 464, respectively. The involvement in catalysis of these carboxyls was examined by modification using the carbodiimide-nucleophile procedure resulting in a complete inactivation of both enzymes. The degree of xylose release from vinasse, an ethanol fermentation by-product, by betaXTE and betaXTR was 12.1% and 7.7%, respectively. Using the beta-xylosidases in combination with the multicomponent enzyme product Ultraflo L, resulted in 41.9% and 40.8% release of xylose, respectively indicating a strong synergistic effect between the exo-acting beta-xylosidases and the endo-1,4-beta-xylanases and alpha-L-arabinofuranosidase in Ultraflo L. There seems to be no measurable differences between the two beta-xylosidases when used in this specific application despite the differences in specific activity and kinetic properties.
The immune response to an isomaltohexosyl-protein conjugate, a thymus-dependent analogue of alpha(1 replaced by 6) dextran. (1982)

Two oligosaccharides derived from B512 dextran (Dex), isomaltohexaose (IM6), and isomaltotriose (IM3) have been coupled to keyhole limpet hemocyanin (KLH) and the conjugates studied as thymus-dependent (TD) immunogens analogous in their specificity to Dex. Both IM3-KLH and IM6-KLH stimulate an anti-Dex response in CBA mice. In C57BL mice, only IM6-KLH stimulated an anti-Dex response; IM3-KLH, although immunogenic, failed to elicit the production of anti-Dex antibodies. Similarly, CBA anti-Dex antibodies cross-reacted with both IM3 and IM6 coupled to bovine serum albumin (BSA), whereas C57BL anti-Dex antibodies cross-reacted with IM6-BSA and bound IM3-BSA only very poorly. This reciprocal lack of cross-reactivity between IM3 conjugates and Dex in C57BL mice was controlled by genes linked to the IgH locus, as shown in responses of allotype congenic CBA mice. This genetically regulated fine specificity pattern was overridden when IM6-KLH was used for immunization. C57BL antibodies that bound both Dex and IM3-BSA were produced in response to this antigen. Thus, isomaltohexosyl-protein conjugates provide Dex-like antigens that differ from Dex itself in terms of thymus dependency and the fine specificity of the precursors that are activated. They should provide important tools to study the activation requirements of antigen-specific B cells.
Cell Senescence: Role in Aging and Age-Related Diseases (2014)

Cell senescence is one of the major paradigms of aging research. It started with the demonstration by L. Hayflick of the limited number of divisions by normal, nontransformed cells, not shown by transformed malignant cells, this processes being largely regulated by the telomere-telomerase system. A complete renewal of this discipline came from the demonstration that cells can enter senescence at any time by an anti-oncogene-triggered pathway, enabling them to escape malignancy. The senescent cell became a major actor of the aging process, among others, by the acquisition of the senescence-associated secretory phenotype. This chapter is devoted to the regulatory process involved in the acquisition of the senescent cell phenotype and its role in organismal aging.
Clostridial Neurotoxins: Mechanism of SNARE Cleavage and Outlook on Potential Substrate Specificity Reengineering (2010)

The clostridial neurotoxin family consists of tetanus neurotoxin and seven distinct botulinum neurotoxins which cause the diseases tetanus and botulism. The extreme potency of these toxins primarily relies not only on their ability to specifically enter motoneurons but also on the activity their catalytic domains display inside presynaptic motoneuronal terminals. Subsequent to neurotoxin binding and endocytosis the catalytic domains become translocated across endosomal membranes and proteolyze unique peptide bonds of one of three soluble N-ethylmaleimide-sensitive fusion protein attachment receptors (SNAREs), vesicle associated membrane protein/synaptobrevin, synaptosome associated protein of 25 kDa, or syntaxin. As these substrate proteins are core components of the vesicular membrane fusion apparatus, cleavage of any of the substrate molecules results in the blockade of neurotransmitter release. This review summarizes the present knowledge about the molecular basis of the specific substrate recognition and cleavage mechanism and assesses the feasibility of reengineering catalytic domains to hydrolyze non-substrate members of the three SNARE families in order to expand the therapeutic application of botulinum neurotoxins.
Controlling and alarming DC power plants via the INTERNET (2002)

The authors describe how the use of the Internet technologies is the next logical step in DC telecommunication power system monitoring and control. They detail how telecommunication companies have spent millions of dollars on internal Intranets with built in firewalls and protection. The infrastructure is there; it is simply a matter of assigning IP addresses to DC power systems.
[Serum myoglobin: evaluation of two immunolatex methods. Comparison with a radioimmunoassay method]. (1992)

Latex immunoturbidimetric (ITA) and immunonephelemetric (INA) assays, were evaluated and compared to a radioimmunological assay (RIA) for the determination of serum myoglobin. Within-run and between-run assays and accuracy and linearity studies gave satisfactory results, very similar to those of RIA. Results were closely correlated with those of RIA for 100 samples of up to 2,000 micrograms/l (correlation coefficients respectively 0.96 and 0.97 for ITA and INA). Reference values (150 men and 150 women; range 20-65 years) were determined and expressed in percentiles. It is concluded that the two latex immunologic assays facilitate laboratory myoglobin evaluation (no radioactive material, short performance time). ITA is more suitable for emergency analysis and INA is more convenient for serial analysis and particular samples (presence of hemoglobin or chylomicrons).
대학 글쓰기 교재의 읽기·쓰기 통합 과제 분석 (2018)

이 연구의 목적은 대학 글쓰기 교재의 읽기·쓰기 통합 과제가 21세기 지식정보화 시대에 요구되는 핵심 능력이자 교양 교육의 목표이기도 한 ‘비판적인 사고 능력’을 신장시키는 데 기여할 수 있도록 조직되었는지 살펴보는 것이다. 이에 2010년대 중후반 이후 출판된 교재 중 읽기·쓰기 통합 과제가 제시되어 있는 4종의 글쓰기 교재를 대상으로 하여, 머리말에 나타난 교재의 목표와 개발 원리, 읽기·쓰기 통합 과제의 목표와 활동 및 활동 절차 등을 분석하였다. 분석 대상이 되는 교재의 읽기·쓰기 통합 과제는 해석, 추론, 분석, 평가의 비판적 사고를 유도해 내도록 읽기 활동과 쓰기 활동을 연계시키지 못하는 것으로 나타났다. 읽기 과제는 쓰기 과제를 위한 전 단계로서 기능하지 못하고 단순히 주제를 도입하거나 주제에 대한 내용 지식을 제시하는 데 그치고 있었다. 또한 쓰기 과제의 목표가 실제의 의사소통적 목적과 연계되지 않아 쓰기 능력을 기르기에는 충분하지 않았다. 쓰기의 의사소통적 본질이 유목적적인 상호작용 행위임에도 불구하고 독자의 중요성을 인식하도록 하는 활동이나 교수자 및 동료 학습자와 상호작용하는 활동을 통해 독자를 고려한 쓰기를 하도록 유도하는 절차가 전혀 제시되지 않아 쓰기 과제를 통해 이러한 능력을 향상시키기도 어려워 보인다. 향후 개발되는 글쓰기 교재에서는 이러한 문제가 극복되어야 할 것이다.
Efficient metadata management in large distributed storage systems (2003)

Efficient metadata management is a critical aspect of overall system performance in large distributed storage systems. Directory subtree partitioning and pure hashing are two common techniques used for managing metadata in such systems, but both suffer from bottlenecks at very high concurrent access rates. We present a new approach called lazy hybrid (LH) metadata management that combines the best aspects of these two approaches while avoiding their shortcomings.
Active Compression-Decompression Resuscitation and Impedance Threshold Device for Out-of-Hospital Cardiac Arrest (2014)

Active compression-decompression resuscitation or impedance threshold device seemed not to improve return of spontaneous circulation in out-of-hospital cardiac arrest patients. The meta-regression indicated two probable prognostic factors causing this minimal effect. Nonetheless, these findings referred to differences between trials and could not necessarily be extrapolated to individual patients. The individual patient-level extrapolation may need to be solved by a future randomized controlled trial.
Restricted expression of a novel retinoic acid responsive gene during limb bud dorsoventral patterning and endochondral ossification (1996)

Using a differential substractive hybridization cloning procedure we have recently identified Stra6 as a novel retinoic acid-induced gene in murine P19 embryonal carcinoma cells. The putative amino acid sequence of Stra6 shows no similarity with previously characterised proteins. We report here the pattern of expression of Stra6 transcripts during mouse limb development as revealed by in situ hybridization. In 8.5-9.0 days post-coitum (dpc) embryos, Stra6 was expressed in the lateral plate mesenchyme prior to limb bud outgrowth. By 9.5 dpc, expression was restricted to the proximal and dorsal forelimb bud mesoderm. Over the next 2 gestational days, Stra6 expression was specific of the dorsal mesoderm of the undifferentiated forelimb and hindlimb buds with the exception of their distal-most region or progress zone. A novel proximal-ventral expression domain appeared, however, by 11.0-11.5 dpc. Stra6 also remained expressed in the flank mesoderm. From 11.5-13.5 dpc, Stra6 expression was restricted to the superficial mesenchyme surrounding the chondrogenic blastemas, and progressively extended until the distal extremities of the limbs upon disappearance of the progress zone. Progressive restriction of Stra6 expression to perichondrium and developing muscles was seen at 13.5-14.5 dpc. Upon the initiation of endochondral ossification (15.5-16.5 dpc), Stra6 expression was limited to the area of perichondrium opposing cells of high metabolic and proliferative activity (the elongation zone). We suggest that Stra6 may play a role in early dorsoventral limb patterning and later in the control of endochondral ossification.
LI.—Action between thiourea and some haloïd derivatives of fatty acids (1893)

A. E. Dixon, J. Chem. Soc., Trans., 1893, 63, 815 DOI: 10.1039/CT8936300815
ORIENTATION (2010)

Alan Read asserts that there is no split between the practice and theory of theatre, but a divide between the written and the unwritten. In this revealing book, he sets out to retrieve the theatre of spontaneity and tactics, which grows out of the experience of everyday life. It is a theatre which defines itself in terms of people and places rather than the idealised empty space of avant garde performance. Read examines the relationship between an ethics of performance, a politics of place and a poetics of the urban environment. His book is a persuasive demand for a critical theory of theatre which is as mentally supple as theatre is physically versatile.
Catalytic Conversion of Methane and Ethylene to Propylene (1998)

Methane and ethylene react over several catalysts to form propylene as the principal product, with (LiCl + NaCl)/MgO being the most effective material. At 650 °C, it was possible to achieve 53% selectivity to C3H6 at a C2H4 conversion of 9.2%. Experiments utilizing 13CH4 demonstrated that one carbon atom in each C3H6 molecule was derived from methane. Methyl radicals, but not vinyl radicals, were detected over these catalysts using a matrix isolation electron spin resonance system. Moreover, it was found that C2H4 inhibited the formation of CH3• radicals. A model calculation, which included both heterogeneous and homogeneous reactions, indicated that most of the propylene was formed neither by the coupling of methyl and vinyl radicals nor via the addition of methyl radicals to ethylene in the gas phase. Rather, it appears that the primary pathway involves the reaction of methyl radicals with adsorbed ethylene to produce propyl radicals, which then lose a hydrogen atom to yield propylene. The instability of the vinyl radical limits the extent to which cross-coupling with methyl radicals can occur.
Sequence-specific 1H NMR assignments, secondary structure, and location of the calcium binding site in the first epidermal growth factor like domain of blood coagulation factor IX (1991)

Factor IX is a blood clotting protein that contains three regions, including a gamma-carboxyglutamic acid (Gla) domain, two tandemly connected epidermal growth factor like (EGF-like) domains, and a serine protease region. The protein exhibits a high-affinity calcium binding site in the first EGF-like domain, in addition to calcium binding in the Gla domain. The first EGF-like domain, factor IX (45-87), has been synthesized. Sequence-specific resonance assignment of the peptide has been made by using 2D NMR techniques, and its secondary structure has been determined. The protein is found to have two antiparallel beta-sheets, and preliminary distance geometry calculations indicate that the protein has two domains, separated by Trp28, with the overall structure being similar to that of EGF. An NMR investigation of the calcium-bound first EGF-like domain indicates the presence and location of a calcium binding site involving residues on both strands of one of the beta-sheets as well as the N-terminal region of the peptide. These results suggest that calcium binding in the first EGF-like domain could induce long-range (possibly interdomain) conformational changes in factor IX, rather than causing structural alterations in the EGF-like domain itself.
Targeting C5a: Recent Advances in Drug Discovery (2005)

Activation of complement via the innate and adaptive immune system is vital to the body's defences in fighting infections. Unregulated complement activation is likely to play a crucial role in the pathogenesis of several diseases including psoriasis, adult (acute) respiratory distress syndrome (ARDS), bullous pemphigoid (BP), rheumatoid arthritis (RA) and ischemia-reperfusion (I/R) injury. The 74 amino acid peptide C5a is released after complement activation at sites of inflammation and is a potent chemoattractant for neutrophils, basophils, eosinophils, leukocytes, monocytes and macrophages. Recombinant proteins and humanized anti-C5 antibodies have been recently developed for blocking specific proteins of the complement system bringing renewed attention towards complement inhibition. Pharmacological studies have been highlighting the complement fragment C5a as an interesting target for the management of complement mediated diseases. Specific inhibition of C5a biological activity could gain therapeutic benefit without affecting the protective immune response. In the last few years several peptide and non-peptide antagonists of C5a have been discovered and tested in relevant pharmacological models; the availability of orally active compounds is rapidly helping to delineate the precise role of C5a in immunoinflammatory disorders. Moreover, mutagenesis data for the C5a/C5a receptor (C5aR) couple make C5aR a valuable model for mechanistic studies of peptidergic G-protein coupled receptors (GPCRs). The aim of this review is to outline the recent advances in C5a inhibition, especially highlighting the value of a multidisciplinary integrated approach in drug discovery.
Comparative Study of Bacterial Groups within the Human Cecal and Fecal Microbiota (2001)

The composition of the human cecal microbiota is poorly known because of sampling difficulties. Samples of cecal fluid from eight subjects were collected via an intestinal tube. Feces were also collected. Total anaerobes, facultative anaerobes, bifidobacteria, and Bacteroides were enumerated by culture methods, and the predominant phylogenetic groups were quantified by molecular hybridization using a set of six rRNA-targeted probes. The numbers of strict anaerobes, bifidobacteria, Bacteroides, and members of the Clostridium coccoides group and Clostridium leptum subgroup were lower in the cecum. Facultative anaerobes represented 25% of total bacteria in the cecum versus 1% in the feces.
Analysis of Reliability and Power Efficiency in Cascode Class-E PAs (2006)

Power efficiency in switched common source class-E amplifiers is usually obtained at the expense of device stress. Device stacking is a viable way to reduce voltage drops across a single device, improving long-term reliability. In this paper, we focus on cascode-based topologies, analyzing the loss mechanisms and giving direction to optimize the design. In particular, a new dissipative mechanism, peculiar of the cascode implementation, is identified and a circuit solution to minimize its effect is proposed. Prototypes, realized in a 0.13-/spl mu/m CMOS technology demonstrate 67% PAE while delivering 23 dBm peak power at 1.7 GHz. Good bandwidth was also realized with greater than 60% PAE over the frequency range of 1.4-2 GHz.
Review: Mitochondrial apoptotic pathways (2005)

Apoptosis or programmed cell death (PCD) is a physiological process characteristic of pluricellular organisms leading to self-destruction of the cell. It is therefore involved in development, homeostasis and host defense. How... | Find, read and cite all the research you need on Tech Science Press