gebhart/patrepeval huggingface dataset:
Cytokinin Oxidase from Phaseolus vulgaris Callus Tissues (1987)

The effects of metal ions on cytokinin oxidase activity extracted from callus tissues of Phaseolus vulgaris L. cv Great Northern have been examined using an assay based on the oxidation of N(6)-(Delta(2)-isopentenyl)-adenine-2,8-(3)H (i(6) Ade) to adenine (Ade). The addition of cupric ions to reaction mixtures containing imidazole buffer markedly enhanced cytokinin oxidase activity. In the presence of optimal concentrations of copper and imidazole, cytokinin oxidase activity was stimulated more than 20-fold. The effect was enzyme dependent, specific for copper, and observed only in the presence of imidazole. The substrate specificity of the copper-imidazole enhanced reaction, as judged by substrate competition tests, was the same as that observed in the absence of copper and imidazole. Similarly, in tests involving DEAE-cellulose chromatography, elution profiles of cytokinin oxidase activity determined using a copper-imidazole enhanced assay were identical to those obtained using an assay without copper and imidazole. On the basis of these results, the addition of copper and imidazole to reaction mixtures used to assay for cytokinin oxidase activity is judged to provide a reliable and specific assay of greatly enhanced sensitivity for the enzyme. The mechanism by which copper and imidazole enhance cytokinin oxidase activity is not certain, but the reaction catalyzed by the enzyme was not inhibited by anaerobic conditions when these reagents were present. This observation suggests that copper-imidazole complexes are substituting for oxygen in the reaction mechanism by which cytokinin oxidase effects cleavage of the N(6)-side chain of i(6)Ade.
A novel leptin receptor isoform in rat (1996)

Five mouse and human leptin receptors (Ob-R) have recently been identified, a long isoform (Ob-Rb), preferentially expressed in hypothalamus, and 4 short isoforms, Ob-Ra, Ob-Rc, Ob-Rd, and Ob-Re. We have identified a new short isoform in the rat, r-OB-Rf, with 6 C-terminal amino acids and a 3' untranslated region without homology to other Ob-R isoforms. Its higher expression in rat liver and spleen compared to brain, stomach, kidney, thymus, heart, lung and hypothalamus, contrasts with Ob-Ra and Ob-Rb homologues and raises possibilities of as yet unidentified roles for members of the growing Ob-R gene family.
Synthesis of a viral protein with molecular weight of 30,000 (p30) by leukemic cells and antibodies cross-reacting with Simian sarcoma virus p30 in serum of a chronic myeloid leukemia patient. (1982)

We studied a patient with a Philadelphia chromosome-positive chronic myeloid leukemia, who died in relapse after multiple transfusions and grafting with bone marrow from his monozygotic twin brother (referred to as "donor" in this paper). We present data indicating that this patient may have had a retro-virus infection that this virus is related to the group of exogenous primate type C retroviruses. Antibodies to simian sarcoma virus (SSV) M.W. 30,000 protein (p30) but not endogenous feline virus RD-114 could be found in patient but not donor serum. Patient but not donor cells were able to actively synthesize a p30 protein that could be precipitated with patient serum and rabbit anti-SSV p30 but not with donor serum or rabbit anti-RD 114 p30. Patient p30 resembles SSV p30 but not RD-114 p30 in peptide mapping by limited proteolysis and subsequent slab gel electrophoresis. Patient but not donor cells were able to actively synthesize a M.W. 78,000 protein that could be precipitated with goat anti-SSV. An enzyme with properties of reverse transcriptase was increased 30-fold ion patient cells when compared with donor and other control cells. Related to the presence of widespread infectious agents may be the finding that, in the course of the patient's disease, donor serum showed increasing amounts of possibly immunoregulatory (Cancer Research, submitted for publication) antibodies, reactive with autologous and, more effectively, with patient-derived cell membrane M. W. 80,000 protein (a possible idiotypic receptor structure) and M.W. 94,000 protein (a T-cell alloantigen).
Observation of a Type II Heterojunction in a Highly Ordered Polymer−Carbon Nanotube Nanohybrid Structure (2009)

We report a study of the electronic properties of the heterojunction between regioregular poly(3-hexylthiophene) (rrP3HT) and single-walled carbon nanotubes (SWNTs). Comparison of the spectroscopic data of nanotube dispersions in a range of polymers indicates significant changes in the nature of the observed SWNT excitons only in combination with rrP3HT. A detailed analysis concludes that a type II heterojunction between rrP3HT and small diameter s-SWNTs is formed, making these particular nanohybrids a promising material for organic photovoltaics.
Follicle-stimulating hormone stimulates estradiol-17beta synthesis in cultured Sertoli cells. (1975)

Sertoli cells isolated from testes of 20-day-old rats and maintained in primary culture synthesized estradiol-17beta [1,3,5(10)-estratriene-3,17beta-diol] (measured by specific radioimmunoassay) when testosterone (17beta-hydroxy-4-androsten-3-one) 0.5 muM, was added to the culture medium. No detectable estradiol synthesis occurred when cells were incubated in medium containing pregnenolone (3beta-hydroxypregn-5-en-20-one), 0.5 muM, or containing no added steroid substrate. Follicle-stimulating hormone (FSH) (NIH-FSH-S10, 5 mug/ml) stimulated estradiol synthesis 12- to 80-fold when added to medium containing testosterone, but not when added to medium containing pregnenolone or no exogenous steroid substrate. A highly purified FSH preparation, with FSH potency 50 times that of the NIH-FSH, caused a similar stimulation at a concentration of 0.25 mug/ml of medium, whereas luteinizing hormone (NIH-LH-S18, 5 MUG/ML) Caused only marginal stimulation. Dibutyryl-adenosine 3':5' cyclic monophosphate, 0.1 mM, caused a 30-fold increase in estradiol synthesis by Sertoli cells cultured in medium containing testosterone. These studies provide direct demonstration of estradiol-17beta production by Seroli cells from normal animals, and offer evidence that the synthesis of this steroid is regulated at the level of the aromatizing enzyme system by FSH and adenosine 3':5' cyclic monophosphate.
Improvement of expression of recombinant human protein C in the milk of transgenic animals using a novel transgene construct (1993)

Past studies of mammary tissue specific expression of transgenes using the murine whey acidic protein (WAP) promoter have shown widely variable, position-dependent and copy number-dependent expression. This study evaluates a series of three WAP transgenes containing the cDNA of human protein C (hPC) for the expression of human protein C in the milk of mice. In two of the transgenes studied, the cDNA of (hPC) was inserted at the translational start site of a 7.8 kbp mouse WAP genomic DNA Eco RI fragment containing 2.6 kbp of 5’ flanking, 3.9 kbp WAP coding (exons and introns), and 1.3 kbp 3’ untranslated region (UTR) and flanking sequences (designated WAPPC1 and WAPPC2). A third transgene consisted of only the 2.6 kbp of WAP 5’ UTR and flanking DNA, 1.4 kbp hPC cDNA, and 1.3 kbp of 3’ WAP UTR and flanking DNA with no linker sequences (designated WAPPC3). The WAPPC1 and WAPPC2 transgenes expressed up to about 10 μg/ml recombinant hPC in mouse milk while WAPPC3 expressed 30-300 (n=10, n=5, n=11, number of founder lines evaluated for each transgene, respectively). In contrast to past studies with WAP-cDNA fusion transgenes where the maximal expression was about 5% of endogenous WAP expression, the WAPPC3 transgene gave maximal expression which was about 30% of endogenous WAP expression. Thus, results from the combination in WAPPC3 of intact 5’ and 3’ WAP UTR with the cDNA of hPC suggests that introns are not necessary to enable high level expression in the mammary gland when using WAP regulatory elements. Relative specific transcript and protein levels in the transgenic animals studied suggest that the rates of translation initiation may be different for the mRNAs of each of the transgenes studied.
Unified Field Theory - 1. Universal Topology and First Horizon of Quantum Fields (2017)

Evolution from the classical dynamics W=P to the spacetime interwoven W=P+iV of modern physics, this paper demonstrates the yinyang physics of nature law: Universal Topology W=P±iV, that intuitively constitutes YinYang Manifolds and Dual Event Operations. Following the yinyang principle, its First Horizon naturally comes out with the YinYang Energy-State Equilibrium and YinYang Motion Dynamics, which replace the empirical “math law” and give rise to the general quantum fields to concisely include Schrodinger and Klein–Gordon Equations. As a result, this becomes a groundwork in the quest for Unified Physics: the workings of a life streaming of yinyang dynamics ...
Removal of N-linked Carbohydrates Decreases the Infectivity of Herpes Simplex Virus Type 1 (1988)

Purified preparations of herpes simplex virus type 1 Angelotti were digested with the exoglycosidases sialidase, beta-galactosidase, N-acetyl-beta-D-glucosaminidase and alpha-mannosidase, and with the endoglycosidases Endo-H and Endo-F. It was found that treatment of virions with Endo-F specifically decreased viral infectivity by a factor of 10. This reduction in titre was not associated with any measurable differences in virus adsorption, suggesting a role of N-linked complex type oligosaccharide chains in penetration. In contrast, a reduction in titre observed upon digestion of virions with exoglycosidases could be attributed to a proteolytic contamination in these enzyme preparations. Treatment of virions with Endo-H, demonstrated to be free of proteolytic contamination, did not reduce viral infectivity. Analysis of endoglycosidase-digested virions by monospecific antibodies and immunoblotting revealed a susceptibility of all four major glycoproteins (gC, gB, gE and gD) to Endo-F, but only gB was susceptible to Endo-H treatment. In contrast, of all the exoglycosidases used only sialidase was found to be active towards native viral glycoproteins. Upon analysis of endoglycosidase-digested virions we could not find any evidence for proteolysis, degradation or altered protein composition of viral envelopes. In contrast, vigorous inhibition of glycoprotein glycosylation by tunicamycin led to the formation of physically intact virions almost completely lacking all major glycoproteins. These data show that digestion of intact virions with glycosidases allows an analysis of the functional relevance of carbohydrate residues without any obvious alterations in the virion glycoprotein composition.
Phenotypic Study of Resistance of β-Lactamase-Inhibitor-Resistant TEM Enzymes Which Differ by Naturally Occurring Variations and by Site-Directed Substitution at Asp 276 (1998)

At this time an amino acid substitution at position 276 in the TEM-1 enzyme is associated with an additional substitution at position 69 in natural beta-lactamase-inhibitor-resistant (IRT) beta-lactamases. The effect of the Asn276-->Asp substitution on resistance was assessed with the Asn276Asp variant, generated by site-directed mutagenesis. The mutant was resistant to beta-lactamase inhibitors, but the MICs of amoxicillin combined with clavulanic acid or tazobactam were strikingly different for E. coli strains producing the Asn276Asp variant and those producing naturally occurring IRTs with single or double substitutions. The inhibitory effects of clavulanic acid and tazobactam were the same in IRTs with substitutions at position 69 (IRT-5 and IRT-6). The effect of clavulanic acid on the MICs of amoxicillin for the Asn276Asp variant was greater than that of tazobactam. In IRTs with double substitutions, at positions 69 plus 276 (IRT-4, IRT-7, and IRT-8) or 69 plus 275 (IRT-14), tazobactam was a more potent inhibitor than clavulanic acid. The effect of the Asn276-->Asp substitution on the values of the kinetic constants and the concentration required to inhibit by 50% the hydrolysis of benzylpenicillin confirms that this single mutation is responsible for resistance to beta-lactamase inhibitors. Molecular modeling of the Asn276Asp mutant shows that Asp276 can form two salt bonds with Arg244 close to the penicillin-binding cavity. The addition of the Asp276 mutation to that preexisting at position 69 confers a higher selective advantage to bacteria, as shown by the reduction in beta-lactamase inhibitor efficiencies of the double variants. Therefore, the emergence of multiple mutations in TEM beta-lactamases by virtue of the use of beta-lactamase inhibitors increases selection pressure resulting in the convergent evolution of resistant strains.
B7-H1 Expression on Non-Small Cell Lung Cancer Cells and Its Relationship with Tumor-Infiltrating Lymphocytes and Their PD-1 Expression (2004)

Abstract Purpose: B7-H1/PD-L1 (B7-H1) and B7-DC/PD-L2 (B7-DC) are ligands for the receptor PD-1, which is known to negatively regulate T-cell activation. In the present study, we investigated the expression of B7-H1 and B7-DC in tumor specimens of non-small cell lung cancer and their relationships with clinicopathological variables and postoperative survival. Furthermore, we examined the correlation between B7-H1 expression on tumor cells and the number of tumor-infiltrating lymphocytes (TILs) or PD-1 expression on TILs. Experimental Design: The expression of B7-H1 and B7-DC in 52 surgically resected specimens of non-small cell lung cancer was evaluated immunohistochemically. Results: Expression of B7-H1 and B7-DC was focally observed in all non-small cell lung cancer tumor specimens. No relationship was found between the expression of B7-H1 or B7-DC and clinicopathological variables or postoperative survival. However, in the same sections evaluated, significantly fewer TILs were identified in B7-H1-positive tumor regions than in B7-H1-negative tumor regions in a subset of five patients (P = 0.01). Moreover, the percentage of TILs expressing PD-1 was significantly lower in B7-H1-positive tumor regions than in B7-H1-negative tumor regions (P = 0.02). Conclusions: The expression of B7-H1 on tumor cells in local areas reciprocally correlated with the number of TILs, and this may contribute to negative regulation in antitumor immune responses in non-small cell lung cancer.
Synthesis of water‐soluble near‐infrared cyanine dyes functionalized with [(succinimido)oxy]carbonyl group (2003)

Abstract Two hetamethine cyanine dyes suitable for labeling of biomolecules at a primary amino group with a near‐infrared chromophore/fluorophore (λ max /(λ em = 800/830 nm and 837/864 nm) have been synthesized from readily available starting materials. Despite the high molecular complexity of intermediate and final products, all these compounds have been obtained in an analytically pure form by using crystallization only.
Targeting mTORC1–Mediated Metabolic Addiction Overcomes Fludarabine Resistance in Malignant B Cells (2014)

This study provides the first evidence for mTORC1/p70S6K-dependent regulation of pyrimidine biosynthesis in a relevant disease setting.
Characterization of the Acyl Substrate Binding Pocket of Acetyl-CoA Synthetase (2006)

AMP-forming acetyl-CoA synthetase [ACS; acetate:CoA ligase (AMP-forming), EC 6.2.1.1] catalyzes the activation of acetate to acetyl-CoA in a two-step reaction. This enzyme is a member of the adenylate-forming enzyme superfamily that includes firefly luciferase, nonribosomal peptide synthetases, and acyl- and aryl-CoA synthetases/ligases. Although the structures of several superfamily members demonstrate that these enzymes have a similar fold and domain structure, the low sequence conservation and diversity of the substrates utilized have limited the utility of these structures in understanding substrate binding in more distantly related enzymes in this superfamily. The crystal structures of the Salmonella enterica ACS and Saccharomyces cerevisiae ACS1 have allowed a directed approach to investigating substrate binding and catalysis in ACS. In the S. enterica ACS structure, the propyl group of adenosine 5'-propylphosphate, which mimics the acyl-adenylate intermediate, lies in a hydrophobic pocket. Modeling of the Methanothermobacter thermautotrophicus Z245 ACS (MT-ACS1) on the S. cerevisiae ACS structure showed similar active site architecture, and alignment of the amino acid sequences of proven ACSs indicates that the four residues that compose the putative acetate binding pocket are well conserved. These four residues, Ile312, Thr313, Val388, and Trp416 of MT-ACS1, were targeted for alteration, and our results support that they do indeed form the acetate binding pocket and that alterations at these positions significantly alter the enzyme's affinity for acetate as well as the range of acyl substrates that can be utilized. In particular, Trp416 appears to be the primary determinant for acyl chain length that can be accommodated in the binding site.
Pharmacological properties of immuno-isolated neuronal nicotinic receptors (1986)

Recently we immunoaffinity-purified an ACh receptor from chicken brain using a monoclonal antibody raised against receptors from fish electric organ (Whiting and Lindstrom, 1986). This neuronal receptor could be affinity-labeled with 3H-bromoacetylcholine, and antisera to it specifically blocked ACh-induced depolarization of chicken ciliary ganglion cells. Here we show that this neuronal ACh receptor binds 3H-nicotine with high affinity (KD = 6.61 +/- 0.13 nM). 3H-Nicotine binding was blocked by various nicotinic cholinergic ligands but not by alpha-bungarotoxin or the muscarinic antagonist atropine. Binding was also blocked by affinity labeling the receptor with bromoacetylcholine (after reduction by dithiothreitol). Additionally, we were able to use rat antisera raised against the chicken brain receptor to isolate a component from detergent extracts of rat brain that also bound 3H-nicotine with high affinity (KD = 1.5 nM). The pharmacology of this putative ACh receptor from rat brain was almost identical to the receptor from chicken brain, and its regional distribution was in good agreement with that of 3H-nicotine binding to rodent brain membranes reported by other workers. Thus, by analogy to the receptor we have purified and characterized from chicken brain, this nicotine-binding component from rat brain is probably a functional mammalian neuronal nicotinic ACh receptor.
Experimental gene therapy of human colon cancer. (1994)

The regulatory subunits of PKA are potential targets to alter growth of human colon cancer cells. Gene therapy directed to alter specific steps in signal transduction pathways may provide new therapeutic strategies.
New Tools for Oligonucleotide Fingerprinting (2001)

Oligonucleotide fingerprinting is an attractive, high-throughput complement to tag sequencing methods to determine the spectrum and abundance of genes in cDNA libraries. This method currently relies on the sequential hybridizations of short, radioactively labeled DNA oligonucleotides to clone arrays. Here, we describe a new environment that substantially improves this technology. Fluorescently labeled peptide nucleic acid (PNA) oligonucleotides are used as hybridization probes. Hybridization results are recorded with a large-field, high-resolution laser scanner developed for this purpose. Automated image analysis allows easy handling of large numbers of hybridization images. Signal interference effects, which limit the gridding density in the radioactive approach, are strongly reduced. The sensitivity of the fluorescence detection demonstrated permits the convenient use of nylon membranes. Hybridization data quality is improved, and its generation is substantially accelerated, simplified, and less expensive.
Induced-current electrical impedance tomography: a 2-d theoretical simulation (2003)

A reconstruction algorithm, based on the modified Newton-Raphson algorithm, was developed for induced-current electrical impedance tomography and studied in theoretical two-dimensional geometry representing a human thorax. The finite-volume method was applied for the discretization of the physical domain, resulting in a symbolic representation of the Jacobian matrix, which is accurate and fast to construct. Several system configurations, differing in the number of excitation coils and electrodes, were simulated, and the performance in thoracic imaging was studied. It was found that a six-coil system shows a significant 40% improvement of conductivity values reconstruction over the three-coil system (an error of 2.06 omega(-1) compared with 3.44 omega(-1)). A number of 32 electrodes was found to be sufficient, being the smallest number of electrodes to still provide a reasonable performance (only 4.2% degradation in average conductivity error compared with the maximum possible 106-electrode system).
Sequence-selective targeting of duplex DNA by peptide nucleic acids. (2010)

Sequence-selective gene targeting constitutes an attractive drug-discovery approach for genetic therapy, with the aim of reducing or enhancing the activity of specific genes at the transcriptional level, or as part of a methodology for targeted gene repair. The pseudopeptide DNA mimic peptide nucleic acid (PNA) can recognize duplex DNA with high sequence specificity and affinity in triplex, duplex and double-duplex invasive modes or non-invasive triplex modes. Novel PNA modification has improved the affinity for DNA recognition via duplex invasion, double-duplex invasion and triplex recognition considerably. Such modifications have also resulted in new approaches to targeted gene repair and sequence-selective double-strand cleavage of genomic DNA.
Novel small peptides with neuroprotective and nootropic properties (2005)

The tripeptide thyrotropin-releasing hormone (TRH) and/or related analogues have shown neuroprotective activity across multiple animal trauma models as well as in a small clinical trial of spinal cord injury. The metabolic product of TRH (cyclo-his-pro) retains physiological activity. We have developed a number of novel cyclic dipeptides that are structurally similar to cyclo-his-pro, and have examined their neuroprotective activity across multiple in vitro models of neuronal injury and after traumatic brain injury (TBI) in rodents. Four such compounds were found to reduce cell death after trophic withdrawal or traumatic injury in primary neuronal cultures; two also protected against glutamate or beta-amyloid neurotoxicity. All compounds significantly improved motor and cognitive recovery after controlled cortical impact injury in mice, and markedly reduced lesion volumes as shown by high field magnetic resonance imaging. Further, compound 35b, which is being developed for clinical trials, also showed considerable neuroprotection after fluid percussion induced TBI in rats, and improved cognitive function after daily administration in chronically brain injured rats. At a mechanistic level, the drugs attenuate both apoptotic and necrotic cell death in primary neuronal cultures, markedly reduce intracellular calcium accumulation after injury, and limit changes in mitochondrial membrane potential and associated cytochrome c release. In addition, microarray studies show that 35b reduces transcriptional changes after injury for a number of genes (and proteins) that may be associated with secondary injury, including cell cycle genes, aquaporins and cathepsins. It also upregulates brain-derived neurotrophic factor (BDNF), heat shock proteins (HSP) and hypoxia inducible factor (HIF). Thus, these novel dipeptides have multipotential actions that make them candidates for the treatment of both acute and chronic neurodegeneration.
Carbonylation of organic halides in the presence of terminal acetylenes; novel acetylenic ketone synthesis (1981)

Aryl, heterocyclic, and vinylic halides react with carbon monoxide and terminal acetylenes at 120 °C or below and 80 atm or below in the presence of triethyl-amine and a catalytic amount of a palladium (II) complex to form acetylenic ketones in 46·7–92·9% yield.