gebhart/patrepeval huggingface dataset:
Cloning of a novel component of A-type K+ channels operating at subthreshold potentials with unique expression in heart and brain (1996)

1. Proteins of the Kv4 or Shal-related subfamily are key components of transient K+ channels (A channels) operating at subthreshold values of the membrane potential. We have cloned and characterized a new mammalian Kv4 or Shal-related cDNA (Kv4.3) that predicts a protein with strong sequence conservation with the other known members of this subfamily. 2. Injection of Kv4.3 transcripts into Xenopus oocytes generates an A type K+ current, with small but physiologically significant differences from the currents expressed by Kv4.2 and Kv4.1 mRNAs. Kv4.3 currents can be modified to resemble native A currents by coinjection with a low molecular weight mRNA fraction from rat brain which does not express detectable currents on its own. Particularly striking is a 7-to-10-fold increase in the rate of recovery from inactivation, a 5- to 10-fold increase in current magnitude and a 3- to 4-fold increase in sensitivity to 4-amino pyridine (4-AP). 3. In situ hybridization histochemistry was used to compare the expression of the three known Kv4 genes. Kv4.2 and Kv4.3 (but not Kv4.1) are abundant in the adult rat brain, with each displaying a specific, but sometimes overlapping pattern of expression. Moreover, a reciprocal gradient of expression of Kv4.2 and Kv4.3 transcripts is seen in some brain areas, such as in the pyramidal cell layers of the hippocampus and the granule cell layer of the cerebellum. Therefore Kv4 proteins may form heteromultimeric channels of distinct subunit composition in different neurons. Moreover, the results suggest that neurons such as pyramidal cells in the hippocampus and granule cells in the cerebellum represent heterogeneous cell populations in terms of their ISA, and hence in their firing patterns. Kv4.2 and Kv4.3 also display complementary expression in the heart, with Kv4.3 being more abundant in atria and Kv4.2 in ventricle. The existence of multiple Kv4 proteins forming channels of variable subunit combinations helps explain the diversity of ISA channels in neurons.
Cloning of a Membrane Protein That Induces a Slow Voltage-Gated Potassium Current (1988)

A rat kidney messenger RNA that induces a slowly activating, voltage-dependent potassium current on its expression in Xenopus oocytes was identified by combining molecular cloning with an electrophysiological assay. The cloned complementary DNA encodes a novel membrane protein that consists of 130 amino acids with a single putative transmembrane domain. This protein differs from the known ion channel proteins but is involved in the induction of selective permeation of potassium ions by membrane depolarization.
Rapid and efficient site-specific mutagenesis without phenotypic selection. (1985)

Several single-base substitution mutations have been introduced into the lacZ alpha gene in cloning vector M13mp2, at 40-60% efficiency, in a rapid procedure requiring only transfection of the unfractionated products of standard in vitro mutagenesis reactions. Two simple additional treatments of the DNA, before transfection, produce a site-specific mutation frequency approaching 100%. The approach is applicable to phenotypically silent mutations in addition to those that can be selected. The high efficiency, approximately equal to 10-fold greater than that observed using current methods without enrichment procedures, is obtained by using a DNA template containing several uracil residues in place of thymine. This template has normal coding potential for the in vitro reactions typical of site-directed mutagenesis protocols but is not biologically active upon transfection into a wild-type (i.e., ung+) Escherichia coli host cell. Expression of the desired change, present in the newly synthesized non-uracil-containing covalently closed circular complementary strand, is thus strongly favored. The procedure has been applied to mutations introduced via both oligonucleotides and error-prone polymerization. In addition to its utility in changing DNA sequences, this approach can potentially be used to examine the biological consequences of specific lesions placed at defined positions within a gene.
Elucidating the Mechanism of Oxygen Reduction for Lithium-Air Battery Applications (2009)

Unlocking the true energy capabilities of the lithium metal negative electrode in a lithium battery has until now been limited by the low capacity intercalation and conversion reactions at the positive electrodes. Abraham et al. (Abraham, K. M.; Jiang, Z. J. Electrochem. Soc. 1996, 143, 1−5) overcame this limitation by removing these electrodes and allowing lithium to react directly with oxygen in the atmosphere, forming the Li-air battery. The Li/O2 battery redox couple has a theoretical specific energy of 5200 W h/kg and represents the ultimate, environmentally friendly electrochemical power source. In this work, we report for the first time the intimate role of electrolyte, in particular the role of ion conducting salts, in determining the reversibility and kinetics of oxygen reduction in nonaqueous electrolytes designed for such applications. Such fundamental understanding of this high energy density battery is crucial to harnessing its full energy potential. The kinetics and mechanisms of O2 reduction in solutions of hexafluorophosphate of the general formula A+PF6−, where A = tetrabutylammonium (TBA), K, Na, and Li, in acetonitrile are reported on glassy carbon electrodes using cyclic voltammetry (CV) and rotating disk electrode (RDE) techniques. The results show that the cations in the electrolyte strongly influence the reduction mechanism of O2. Larger cations represented by TBA salts displayed reversible O2/O2− redox couple, in contrast to those containing the smaller Li (and other alkali metal) cations, where an irreversible one-electron reduction of O2 to LiO2, and other alkali metal superoxides, is shown to occur as the first process. It was also found the LiO2 formed initially decomposes to Li2O2. Electrochemical data support the view that alkali metal oxides formed via electrochemical and chemical reactions passivate the electrode surface, making the processes irreversible. The O2 reduction mechanisms in the presence of the different cations have been supplemented by kinetic parameters determined from detailed analyses of the CV and RDE data. The Lewis acid characteristics of the cation appear to be crucial in determining the reversibility of the system. The results of this study are expected to contribute to the rapid development of the Li-air battery.
First trimester endocrinology: consequences for diagnosis and treatment of pregnancy failure (2004)

First-trimester endocrinology is determined on the one hand by corpus luteum progesterone and estradiol biosynthesis and secretion and on the other hand by the time of onset and extent of progesterone and estradiol secretion by the placenta. This dual interplay is dominated by the corpus luteum placental shift, where a relative progesterone and estradiol deficiency can develop and may lead to early as well as late abortion. Measurements of serum progesterone and estradiol are mandatory in order to reveal such deficiencies and to treat them effectively with 17 alpha-hydroxyprogesterone caproate in combination with estradiol valerate or with progestins such as dydrogesterone.
Characterization of 8p21.3 chromosomal deletions in B-cell lymphoma: TRAIL-R1 and TRAIL-R2 as candidate dosage-dependent tumor suppressor genes (2005)

Deletions of chromosome 8p are a recurrent event in B-cell non-Hodgkin lymphoma (B-NHL), suggesting the presence of a tumor suppressor gene. We have characterized these deletions using comparative genomic hybridization to microarrays, fluorescence in situ hybridization (FISH) mapping, DNA sequencing, and functional studies. A minimal deleted region (MDR) of 600 kb was defined in chromosome 8p21.3, with one mantle cell lymphoma cell line (Z138) exhibiting monoallelic deletion of 650 kb. The MDR extended from bacterial artificial chromosome (BAC) clones RP11-382J24 and RP11-109B10 and included the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor gene loci. Sequence analysis of the individual expressed genes within the MDR and DNA sequencing of the entire MDR in Z138 did not reveal any mutation. Gene expression analysis and quantitative reverse transcriptase-polymerase chain reaction (QRT-PCR) showed down-regulation of TRAIL-R1 and TRAIL-R2 receptor genes as a consistent event in B-NHL with 8p21.3 loss. Epigenetic inactivation was excluded via promoter methylation analysis. In vitro studies showed that TRAIL-induced apoptosis was dependent on TRAIL-R1 and/or -R2 dosage in most tumors. Resistance to apoptosis of cell lines with 8p21.3 deletion was reversed by restoration of TRAIL-R1 or TRAIL-R2 expression by gene transfection. Our data suggest that TRAIL-R1 and TRAIL-R2 act as dosage-dependent tumor suppressor genes whose monoallelic deletion can impair TRAIL-induced apoptosis in B-cell lymphoma.
Removing camera shake from a single photograph (2006)

Camera shake during exposure leads to objectionable image blur and ruins many photographs. Conventional blind deconvolution methods typically assume frequency-domain constraints on images, or overly simplified parametric forms for the motion path during camera shake. Real camera motions can follow convoluted paths, and a spatial domain prior can better maintain visually salient image characteristics. We introduce a method to remove the effects of camera shake from seriously blurred images. The method assumes a uniform camera blur over the image and negligible in-plane camera rotation. In order to estimate the blur from the camera shake, the user must specify an image region without saturation effects. We show results for a variety of digital photographs taken from personal photo collections.
Survival of Bacteria Harmful,Effects of Light, with some Comparisons with other Adverse Physical Agents (1967)

Human coronavirus (HCoV) infection causes respiratory diseases with mild to severe outcomes. In the last 15 years, we have witnessed the emergence of two zoonotic, highly pathogenic HCoVs: severe acute respiratory syndrome coronavirus (SARS-CoV) and ...Read More
Cobalt Catalysts for the Alternating Copolymerization of Propylene Oxide and Carbon Dioxide:  Combining High Activity and Selectivity (2005)

Synthetic pathways to (salcy)CoX (salcy = N,N'-bis(3,5-di-tert-butylsalicylidene)-1,2-diaminocyclohexane; X = halide or carboxylate) complexes are described. Complexes (R,R)-(salcy)CoCl, (R,R)-(salcy)CoBr, (R,R)-(salcy)CoOAc, and (R,R)-(salcy)CoOBzF(5) (OBzF(5) = pentafluorobenzoate) are highly active catalysts for the living, alternating copolymerization of propylene oxide (PO) and CO(2), yielding poly(propylene carbonate) (PPC) with no detectable byproducts. The PPC generated using these catalyst systems is highly regioregular and has up to 99% carbonate linkages with a narrow molecular weight distribution (MWD). Inclusion of the cocatalysts [PPN]Cl or [PPN][OBzF(5)] ([PPN] = bis(triphenylphosphine)iminium) with complex (R,R)-(salcy)CoCl, (R,R)-(salcy)CoBr, or (R,R)-(salcy)CoOBzF(5) results in remarkable activity enhancement of the copolymerization as well as improved stereoselectivity and regioselectivity with maximized reactivity at low CO(2) pressures. In the case of [PPN]Cl with (R,R)-(salcy)CoOBzF(5), an unprecedented catalytic activity of 620 turnovers per hour is achieved for the copolymerization of rac-PO and CO(2), yielding iso-enriched PPC with 94% head-to-tail connectivity. The stereochemistry of the monomer and catalyst used in the copolymerization has dramatic effects on catalytic activity and the PPC microstructure. Using catalyst (R,R)-(salcy)CoBr with (S)-PO/CO(2) generates highly regioregular PPC, whereas using (R)-PO/CO(2) with the same catalyst gives an almost completely regiorandom copolymer. The rac-PO/CO(2) copolymerization with catalyst rac-(salcy)CoBr yields syndio-enriched PPC, an unreported PPC microstructure. In addition, (R,R)-(salcy)CoOBzF(5)/[PPN]Cl copolymerizes (S)-PO and CO(2) with a turnover frequency of 1100 h(-1), an activity surpassing that observed in any previously reported system.
Multi-standard DSP based wireless system (2002)

The rapid growth in wireless communications has pushed semiconductor manufacturers to seek low cost, highly integrated and multi-standard designs for wireless handsets due to the current marketing situation i.e. the existing different air interfaces of wireless systems. This paper will focus on the description of: 1) Different kinds of multi-standard DSP based transceiver architectures including the analog mixing function, 2) The advantages and a technical overview of the different kinds of multi-standard transceiver and, 3) Describe the new architecture: single conversion band pass sampling DSP based multi-standard receiver. The paper also looks at the different standards and focuses on a high level design example of a new receiver architecture for this multi-standard specification such as GSM, DCS1800, DECT, PHS, FHSS-DCT and FHSS-WLAN.
Continuous Noninvasive Determination of Pulsus Paradoxus: A Pilot Study (1995)

An accurate and continuous PP can be measured noninvasively using a FINAP monitor. This method has much better agreement with IAP measurements than do manual measurements. The qualitative information provided by the oximeter pulse waveform is less accurate than that provided by the FINAP monitor, but is a potentially useful screening tool for detection of significant PP.
A Conserved Negative Regulatory Region in αPAK: Inhibition of PAK Kinases Reveals Their Morphological Roles Downstream of Cdc42 and Rac1 (1998)

AlphaPAK in a constitutively active form can exert morphological effects (E. Manser, H.-Y. Huang, T.-H. Loo, X.-Q. Chen, J.-M. Dong, T. Leung, and L. Lim, Mol. Cell. Biol. 17:1129-1143, 1997) resembling those of Cdc42G12V. PAK family kinases, conserved from yeasts to humans, are directly activated by Cdc42 or Rac1 through interaction with a conserved N-terminal motif (corresponding to residues 71 to 137 in alphaPAK). alphaPAK mutants with substitutions in this motif that resulted in severely reduced Cdc42 binding can be recruited normally to Cdc42G12V-driven focal complexes. Mutation of residues in the C-terminal portion of the motif (residues 101 to 137), though not affecting Cdc42 binding, produced a constitutively active kinase, suggesting this to be a negative regulatory region. Indeed, a 67-residue polypeptide encoding alphaPAK83-149 potently inhibited GTPgammaS-bound Cdc42-mediated kinase activation of both alphaPAK and betaPAK. Coexpression of this PAK inhibitor with Cdc42G12V prevented the formation of peripheral actin microspikes and associated loss of stress fibers normally induced by the p21. Coexpression of PAK inhibitor with Rac1G12V also prevented loss of stress fibers but not ruffling induced by the p21. Coexpression of alphaPAK83-149 completely blocked the phenotypic effects of hyperactive alphaPAKL107F in promoting dissolution of focal adhesions and actin stress fibers. These results, coupled with previous observations with constitutively active PAK, demonstrate that these kinases play an important role downstream of Cdc42 and Rac1 in cytoskeletal reorganization.
Deletion of Ile1 Changes the Mechanism of Streptokinase:  Evidence for the Molecular Sexuality Hypothesis (1999)

Plasminogen (Plgn) is usually activated by proteolytic cleavage of Arg561-Val562. The new N-terminal amino group of Val562 forms a salt bridge with Asp740, creating the active protease plasmin (Pm). However, streptokinase (SK) binds to Plgn, generating an active protease in a poorly understood, nonproteolytic process. We hypothesized that the N-terminus of SK, Ile1, substitutes for the N-terminal Val562 of Pm, forming an analogous salt bridge with Asp740. SK initially forms an inactive complex with Plgn, which subsequently rearranges to create an active complex; this rearrangement is rate limiting at 4 degrees C. SK.Plgn efficiently hydrolyzes amide substrates at 4 degrees C, although DeltaIle1-SK. Plgn has no amidolytic activity. DeltaIle1-SK prevents formation of wild-type SK.Plgn. These results indicate that DeltaIle1-SK forms the initial inactive complex with plasminogen, but cannot form the active complex. However, when the experiment is performed at 37 degrees C, amidolytic activity is observed when DeltaIle1-SK is added to plasminogen. SDS-PAGE analysis demonstrates that the amidolytic activity results from the formation of DeltaIle1-SK.Pm. To further demonstrate that the activity of DeltaIle1-SK requires the conversion of Plgn to Pm, we characterized the reaction of SK with a mutant microplasminogen, Arg561Ala-microPlgn, that cannot be converted to microplasmin. Amidolytic activity is observed when Arg561Ala-microPlgn is incubated with wild-type SK at 37 degrees C; however, no amidolytic activity is observed in the presence of DeltaIle1-SK. These observations demonstrate that the amidolytic activity of DeltaIle1-SK at 37 degrees C requires the conversion of Plgn to Pm. Our findings indicate that Ile1 of SK is required for the nonproteolytic activation of Plgn by SK and are consistent with the hypothesis that Ile1 of SK substitutes for Val562 of Pm.
The ups and downs of nucleic acid duplex stability: structure-stability studies on chemically-modified DNA:RNA duplexes (1997)

In an effort to discover novel oligonucleotide modifications for antisense therapeutics, we have prepared oligodeoxyribonucleotides containing more than 200 different modifications and measured their affinities for complementary RNA. These include modifications to the heterocyclic bases, the deoxy-ribose sugar and the phosphodiester linkage. From these results, we have been able to determine structure-activity relationships that correlate hybridization affinity with changes in oligonucleotide structure. Data for oligonucleotides containing modified pyrimidine nucleotides are presented. In general, modifications that resulted in the most stable duplexes contained a heteroatom at the 2'-position of the sugar. Other sugar modifications usually led to diminished hybrid stability. Most backbone modifications that led to improved hybridization restricted backbone mobility and resulted in an A-type sugar pucker for the residue 5'to the modified internucleotide linkage. Among the heterocycles, C-5-substituted pyrimidines stood out as substantially increasing duplex stability.
Precision of the larsen and the sharp methods of assessing radiologic change in patients with rheumatoid arthritis (1992)

Sharp's radiographic scoring method seems to be more sensitive to change over time than is Larsen's method. The clinical importance of the change needs to be definitively established.
Imprinted Segments in the Human Genome: Different Dna Methylation Patterns in the Prader-Willi/Angelman Syndrome Region As Determined by the Genomic Sequencing Method (1997)

A deletion of 15q11-q13 and uniparental disomy 15 lead to Prader-Labhart-Willi syndrome (PWS) or Angelman syndrome (AS) because this region contains genes expressed exclusively from the paternal (PWS) or maternal (AS) chromosome, respectively. DNA methylation plays a role in the control of imprinted gene expression, but so far only a few 5'-CG-3' dinucleotides within the recognition sites of the methylation sensitive enzymes have been studied. As part of a study on DNA methylation patterns in the human genome, we have applied the bisulfite protocol of genomic sequencing to study all 5'-CG-3' dinucleotides around exon 1 of SNRPN and at the D15S63 locus, which contains a start site for alternative SNRPN transcripts possibly involved in imprint switching during gametogenesis. At least 17 PCR products derived from single chromosomes of normal individuals as well as PWS and AS patients have been sequenced. We have found that cytosine residues outside 5'-CG-3' dinucleotides are always unmethylated. However, > 96% of all of the 23 5'-CG-3' dinucleotides around SNRPN exon 1 are methylated on the maternal chromosome and completely devoid of methylation on the paternal chromosome. This finding is in contrast to the D15S63 locus, where only the two Cfol/Hhal sites are methylated on the maternal chromosome at the same frequency as seen for the SNRPN segment. At the other five 5'-CG-3' dinucleotides, differential methylation is less pronounced, i.e. 45-70% on the maternal chromosome and 5-14% on the paternal chromosome. The differences between SNRPN and D15S63 methylation may reflect different biological functions of the alternative SNRPN transcripts. The systematic investigation of 5'-CG-3' methylation patterns as reported here will provide the basis for a PCR-based methylation test to diagnose PWS and AS.
Weekly Feed Consumption of Light Consumer-Size Turkeys Raised in Utah (2000)

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Effect of conformational mobility and hydrogen-bonding interactions on the selectivity of some guanidinoaryl-substituted mechanism-based inhibitors of trypsin-like serine proteases (1992)

Previously, we have reported that some guanidino-substituted alpha- and beta-aryl enol lactones I and II behaved as selective, mechanism-based inhibitors of some trypsin-like proteases (Rai, R.; Katzenellenbogen, J.A. J. Med. Chem., submitted). In this study, we describe the synthesis and kinetic evaluation of some related, guanidino-substituted enol lactones having greater conformational mobility and affording additional hydrogen-bonding sites at the active site. The alpha-aryl-substituted lactones 1 and 2, which have greater conformational mobility in the guanidinoaryl linkage than I, selectively inhibited the trypsin-like enzymes, and they were relatively poor inactivators of alpha-chymotrypsin and human neutrophil elastase (HNE). The iodo enol lactone 2 permanently inactivated trypsin, urokinase, tissue plasminogen activator, and plasmin, showing exceptionally high specificity in its interaction with trypsin and urokinase. The selectivity pattern exhibited by the closely related, conformationally less mobile alpha-aryl-substituted iodo lactone Ib, which was previously shown to be a selective suicide substrate of urokinase and plasmin, provides an interesting comparison. The alpha-benzamido-substituted lactones 3 and 4, which afford an additional site for active-site hydrogen bonding, were found to be very potent alternate substrate inhibitors of trypsin and urokinase. In addition, the iodo lactone 4 permanently inactivated alpha-chymotrypsin. The importance of secondary interactions in increasing the specificities in the case of alpha-chymotrypsin is discussed.
Use of evans blue dye to compare limb muscles in exercised young and old mdx mice (2009)

Evans blue dye (EBD) is used to mark damaged and permeable muscle fibers in mouse models of muscular dystrophy and as an endpoint in therapeutic trials. We counted EBD-positive muscle fibers and extracted EBD from muscles sampled throughout the hindlimbs in young adult and old mdx mice to determine if the natural variability in morphology would allow measurement of a functional improvement in one limb compared to the contralateral limb. Following one bout of rotarod or treadmill exercise that greatly increased serum creatine kinase levels, the number of EBD(+) muscle fibers in 12-19-month-old mdx mice increased 3-fold, EBD in the muscles increased, and, importantly, contralateral pairs of muscles contained similar amounts of EBD. In contrast, the intra- and interlimb amounts of EBD in 2-7-month-old mdx mice were much too variable. A therapeutic effect can more readily be measured in old mdx mice. These results will be useful in the design of therapy protocols using the mdx mouse.
Heterocyclische Siebenring-Verbindungen, XXIY [1]. Photochemische Reaktion von 2-Methyl-4-phenyl-1-benzothiepinen / Heterocyclic Seven-membered Ring Compounds, XXIV [1]. Photochemical Reaction of 2-Methyl-4-phenyl-1-benzothiepins (1982)

The photoreaction of the 2-methyl-4-phenyl-1-benzothiepins 1a und 1b leads first to the not isolated primary pliotoproducts 2 a and 2 b. These were entirely transformed to the secondary pliotoproducts 3a and 3b in the course of the irridation.