gebhart/patrepeval huggingface dataset:
Response of human breast cancer cells to heat shock and chemotherapeutic drugs. (1992)

Previous studies have shown that certain chemotherapeutic drugs are less effective on tumor cells when cells have been previously exposed to hyperthermia. In the present study, we have evaluated whether specific modifications in heat shock protein (hsp) expression are associated with resistance to anticancer drugs. RNA levels for hsp90, hsp70, and hsp27 were studied by Northern and slot blots, while proteins were studied by two-dimensional gel electrophoresis, in MCF-7/BK and MDA-MB-231 breast cancer cells. The sensitivities of these cells to doxorubicin, colchicine, 5-fluorouracil, cisplatin, actinomycin D, and methotrexate were tested by clonogenic assays. These techniques were applied to both cell lines before (control) and after heat shock. The study revealed that elevated hsp70 and hsp27 levels were associated with doxorubicin resistance. In addition, the presence of phosphorylated hsp27 isoforms was also associated with doxorubicin resistance. The study showed that elevated hsps were not associated with multidrug resistance. Heat shock did not induce P170 glycoprotein mRNA overexpression or resistance to the other drugs tested. We also found that the level of doxorubicin protection conferred by the overexpression of hsp was lower than that obtained in cells expressing a multidrug resistance phenotype (MDA-A1R cells). In these cells, heat shock did not confer additional doxorubicin resistance and hsp27 phosphorylation was deficient. Our studies suggest that specific hsps are associated with doxorubicin resistance in certain human breast cancer cells and that this mechanism seems to be independent of the multidrug resistance system.
Mapping studies and expression of genes located on human chromosome 11, band q23 (1988)

Chromosome translocations and deletions may alter cellular proto-oncogenes and result in cellular changes that are important in the pathogenesis of malignancy. The region 11q23 is frequently involved in human malignancy. Utilizing a leukemic cell line with a reciprocal translocation involving 11q23 and somatic cell hybrids derived from this cell line, we analyzed five genes assigned to 11q23: NCAM, CD3D, CD3E, THY1, and ETS1. Our data showed no evidence of direct involvement of these genes in this leukemia but enabled a partial genetic map of this important region of the human genome to be constructed: 11cen--NCAM--CD3([G, D], E)--parallel--(ETS1, THY1)--11qter.
Anti-cancer and potential chemopreventive actions of ginseng by activating Nrf2 (NFE2L2) anti-oxidative stress/anti-inflammatory pathways (2010)

This article reviews recent basic and clinical studies of ginseng, particularly the anti-cancer effects and the potential chemopreventive actions by activating the transcriptional factor, nuclear factor (erythroid-derived 2)-like 2 (Nrf2 or NFE2L2)-mediated anti-oxidative stress or anti-inflammatory pathways. Nrf2 is a novel target for cancer prevention as it regulates the antioxidant responsive element (ARE), a critical regulatory element in the promoter region of genes encoding cellular phase II detoxifying and anti-oxidative stress enzymes. The studies on the chemopreventive effects of ginseng or its components/products showed that Nrf2 could also be a target for ginseng's actions. A number of papers also demonstrated the anti-inflammatory effects of ginseng. Targeting Nrf2 pathway is a novel approach to the investigation of ginseng's cancer chemopreventive actions, including some oxidative stress and inflammatory conditions responsible for the initiation, promotion and progression of carcinogenesis.
Two-Stage Charge Transfer Pixel Using Pinned Diodes for Low-Noise Global Shutter Imaging (2024)

This paper describes a new type of global electronic shutter pixel for CMOS image sensors. A global electronic shutter is necessary for imaging fast-moving objects without motion blur or distortion. The proposed pixel has two potential wells with pinned diode structure for two-stage charge transfer that enables a global electronic shuttering and reset noise canceling.
Recent Advances in the Development of NR2B Subtype-Selective NMDA Receptor Antagonists (2006)

Over activation of the NMDA receptor complex has been implicated in a number of neurological conditions. The use of NMDA antagonists as therapeutic agents has been limited by serious cognitive and motor side effects. Significant efforts have been reported in the development of NR2B subtype-selective antagonists, which have shown efficacy without the side effects observed with nonspecific NMDA antagonists. Classical ifenprodil-like molecules containing benzyl- and phenylpiperidines attached to a phenol or an appropriate isostere by a linker have provided valuable chemical leads as potential therapeutic agents. In this review, recent efforts in the discovery and development of structurally unique NR2B subtype-selective NMDA antagonists that do not fit the classical "ifenprodil-like" pharmacophore will be discussed.
The Cleavage of Ethers. (1954)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Cleavage of Ethers.Robert L. Burwell, Jr.Cite this: Chem. Rev. 1954, 54, 4, 615–685Publication Date (Print):August 1, 1954Publication History Published online1 May 2002Published inissue 1 August 1954https://pubs.acs.org/doi/10.1021/cr60170a003https://doi.org/10.1021/cr60170a003research-articleACS PublicationsRequest reuse permissionsArticle Views4539Altmetric-Citations244LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Human cardiac stem cells (2007)

The identification of cardiac progenitor cells in mammals raises the possibility that the human heart contains a population of stem cells capable of generating cardiomyocytes and coronary vessels. The characterization of human cardiac stem cells (hCSCs) would have important clinical implications for the management of the failing heart. We have established the conditions for the isolation and expansion of c-kit-positive hCSCs from small samples of myocardium. Additionally, we have tested whether these cells have the ability to form functionally competent human myocardium after infarction in immunocompromised animals. Here, we report the identification in vitro of a class of human c-kit-positive cardiac cells that possess the fundamental properties of stem cells: they are self-renewing, clonogenic, and multipotent. hCSCs differentiate predominantly into cardiomyocytes and, to a lesser extent, into smooth muscle cells and endothelial cells. When locally injected in the infarcted myocardium of immunodeficient mice and immunosuppressed rats, hCSCs generate a chimeric heart, which contains human myocardium composed of myocytes, coronary resistance arterioles, and capillaries. The human myocardium is structurally and functionally integrated with the rodent myocardium and contributes to the performance of the infarcted heart. Differentiated human cardiac cells possess only one set of human sex chromosomes excluding cell fusion. The lack of cell fusion was confirmed by the Cre-lox strategy. Thus, hCSCs can be isolated and expanded in vitro for subsequent autologous regeneration of dead myocardium in patients affected by heart failure of ischemic and nonischemic origin.
Detection of Human Skin in Near Infrared Hyperspectral Imagery (2008)

One of the difficulties in search and rescue missions is finding a small target, such as a person, in a large cluttered area. Airborne hyperspectral cameras are now being deployed to aid in this SAR mission. Motivated by the successes of such systems, we define a hyperspectral model of human skin in the visible and near infrared regions of the spectra so we can exploit knowledge gained during the modeling process to aid in human skin detection. Based on observations of the skin model results, an efficient and robust skin detection algorithm using channels in the near infrared region of the spectra is developed. Our algorithm is denoted the Normalized Difference Skin Index, motivated by the Normalized Difference Vegetation Index used in the literature for detecting vegetation in hyperspectral imagery. We demonstrate the capabilities of our skin detection methodology to detect skin amongst objects known to cause false detections for methodologies using three channel color data.
Interaction of Model Class A1, Class A2, and Class Y Amphipathic Helical Peptides with Membranes (1996)

To test the hypothesis that differences in the lipid affinity of exchangeable apolipoproteins are due to the presence of different classes of amphipathic alpha-helical motifs which differ primarily in the distribution of charged amino acid residues, we designed and synthesized model peptides mimicking class A1, class A2, and class Y amphipathic helices present in these apolipoproteins. Both class A1 and class A2 helices have positive residues at the polar-nonpolar interface and negative residues at the center of the polar face. However, clustering of positive and negative residues is less exact in class A1 compared to class A2 helices. The class Y helices have two negative residue clusters on the polar face separating the two arms and the base of the Y motif formed by three positive residue clusters. The lipid affinities of three 18 residue model peptides representing these classes, Ac-18A1-NH2 (Ac-ELLEKWAEKLAALKEALK-NH2), Ac-18A2-NH2 (Ac-ELLEKWKEALAALAEKLK-NH2), and Ac-18Y-NH2 (Ac-ELLKAWKEALEALKEKLA-NH2), were determined by right-angle light scattering, circular dichroism spectroscopy, differential scanning calorimetry, and fluorescence spectroscopy. The observed rank order of lipid affinity of these three peptides is: Ac-18A2-NH2 > Ac-18Y-NH2 > Ac-18A1-NH2. This order is consistent with the known lipid affinity of exchangeable apolipoproteins containing class A1, class A2, and class Y helices (class A2 > class Y > class A1). Results of this study illustrate the important role of interfacial lysine residues in modulating the lipid affinity of amphipathic helices and suggest that the effect of interfacial lysine residues in increasing lipid affinity is additive. We propose that interfacial lysine residues, in addition to widening the hydrophobic face because of snorkeling, also help anchor the amphipathic helix in the lipid bilayer.
High-Level Expression in Escherichia coli of Biologically Active Bovine Growth Hormone (1985)

High-level synthesis of bovine growth hormone (bGH) in Escherichia coli was achieved by maximizing gene transcription and optimizing the translational efficiency of bGH mRNA. Nearly all of the recombinant hormone was found in the pellet fraction after bacterial cell lysis. This property allowed the purification of bGH nearly to homogeneity. Protein sequence analysis indicated that greater than 93% of the purified hormone had the amino-terminal methionine residue removed by E. coli, yielding mature bGH. In a hypophysectomized rat assay system, purified bacterial-produced bGH demonstrated growth-promoting activity equivalent to that of pituitary-derived bovine growth hormone.
Mesenchymal Stem Cells in Acute Kidney Injury (2007)

The potential role of mesenchymal stem cells (MSCs, also called mesenchymal stromal cells) in endogenous repair and cell-based therapies for acute kidney injury (AKI) is under intensive investigation. Preclinical studies indicate that administered MSCs both ameliorate renal injury and accelerate repair. These versatile cells home to sites of injury, where they modulate the repair process. The mechanisms responsible for their protective and regenerative effects are incompletely understood. Some have reported that MSCs are capable of direct engraftment into injured nephrons under certain circumstances. This is highly controversial, however, and even those who argue there is engraftment acknowledge that the primary means of repair by these cells most likely involves paracrine and endocrine effects, including mitogenic, antiapoptotic, anti-inflammatory, and angiogenic influences. There is a good deal of interest in MSC-based approaches for the treatment of human kidney injury, thanks to positive preclinical results, the strong clinical need for novel therapies to treat AKI, the ease of isolation and expansion of MSCs, and encouraging preliminary clinical trial results in other fields. This review summarizes current knowledge and identifies gaps in our understanding of MSC biology that will need to be filled in order to translate recent discoveries into therapies for AKI in humans.
How to Spot the Future (2012)

Although increased enteric permeability is more prevalent among children being discharged from hospital compared to children in the community, it does not appear to be an important determinant of systemic inflammation or post-discharge growth among hospitalized children.
Conditioned Medium from Mouse Sarcoma 180 Cells Contains Vascular Endothelial Growth Factor (1990)

Medium conditioned by mouse sarcoma 180 cells stimulates the growth of capillary endothelial cells. The growth factor produced by mouse sarcoma 180 cells is heparin-binding, dithiothreitol-sensitive, endothelial cell specific, and secreted into the medium. The characteristics of this mouse sarcoma-derived growth factor are very similar to those of vascular endothelial growth factor (VEGF) first described by Ferrara and Henzel (1989). The N-terminal amino acid sequences of the two growth factors are similar. Since the amino acid sequence of vascular permeability factor (VPF) is essentially identical to that of VEGF, a Western blot of mouse sarcoma 180-derived endothelial growth factor was probed with a polyclonal antibody raised against human VPF. This antibody reacted with several proteins of approximately 23 kDa, suggesting the presence of multiple forms of a VEGF-like protein. A full length cDNA probe for bovine VEGF reacted strongly with RNA isolated from mouse sarcoma 180 cells. We conclude that an endothelial growth factor found in conditioned medium from mouse sarcoma 180 cells is VEGF.
Six-Membered Metalla-coronands. Synthesis and Crystal Packing:  Columns, Compartments, and 3D-Networks, (2004)

Reaction of various N-substituted diethanolamines H(2)L(3) (4) with calcium hydride and iron(III) chloride leads to the self-assembly of six-membered ferric wheels [Fe(6)X(6)(L(3))(6)] (5). Principally, all the iron coronands are isostructural; however, they differ fundamentally with respect to their crystal packing. Exemplarily, this is discussed for selected members of the space groups R, P, P2(1)/c, P2(1)/n, C2/c, and P. Depending on the nature of their sidearms, the ferric wheels create various substructures. For instance, the ferric wheels 5a-i of space group R or P are piled in parallel in cylindrical columns, which are surrounded by six parallel columns alternately dislocated by (1)/(3)c and (2)/(3)c against the central one. Pronounced van der Waals interactions give rise to compartmentation and incarceration of guest molecules as seen for 5e,g. However, in 5h strong pi-pi interactions create a three-dimensional scaffold. The most significant difference of the ferric wheels 5j-p of space groups P2(1)/c, P2(1)/n, and C2/c is that these ferric wheels are arranged in parallel in two orientations. They differ mainly only by the included angle of the two groups of parallel wheels. In the case of 5l, molecular chains are formed in the crystal due to pi-pi interactions. The ferric wheels 5q-y of space group P are packed in the crystal most simply, with all the ferric wheels piled in parallel.
Recombinant Glutamic Acid Decarboxylase (Representing the Single Isoform Expressed in Human Islets) Detects IDDM-Associated 64,000-Mr Autoantibodies (1992)

GAD is an autoantigen in IDDM. Molecular cloning and specific antibodies allowed us to demonstrate that only the lower M(r) GAD64 isoform is expressed in human islets, in contrast to human brain, rat islets, and rat brain, all of which express both GAD64 and GAD67. Expression of the human islet GAD64 isoform in COS-7 and BHK cells resulted in an enzymatically active rGAD64, which is immunoreactive with diabetic sera comparable with that of the islet 64,000-M(r) autoantigen. Immunoprecipitation analyses showed that 21/28 (75%) IDDM sera had rGA D64 antibodies compared with only 1/59 (1.7%) of the healthy control sera. In immunoblot analyses, an SMS serum--but only 1/10 randomly selected IDDM sera--recognized the blotted rGAD64 without relation to immunoprecipitation titers. In conclusion, only the GA D64 isoform is expressed in human islets, in contrast to rat islets, which also express the GAD67 isoform. The immunological properties of human rGAD64 are comparable with the native 64,000-M(r) islet autoantigen, allowing further studies of the immunopathogenesis of IDDM.
Development of PPO inhibitor‐resistant cultures and crops (2005)

Recent progress in the development of protoporphyrinogen oxidase (PPO, Protox) inhibitor-resistant plant cell cultures and crops is reviewed, with emphasis on the molecular and cellular aspects of this topic. PPO herbicide-resistant maize plants have been reported, along with the isolation of plant PPO genes and the isolation of herbicide-resistant mutants. At the same time, PPO inhibitor-resistant rice plants have been developed by expression of the Bacillus subtilis PPO gene via targeting the gene into either chloroplast or cytoplasm. Other attempts to develop PPO herbicide-resistant plants include conventional tissue culture methods, expression of modified co-factors of the protoporphyrin IX binding subunit proteins, over-expression of wild-type plant PPO gene, and engineering of P-450 monooxygenases to degrade the PPO inhibitor.
Exchange bias and giant magnetoresistance in spin valves with pico-scale antiferromagnetic layers (2005)

This work uses the giant magnetoresistance (GMR) of spin valves with pico-scale IrMn layers to determine the exchange biasing effects. The samples were prepared by magnetron sputtering. This paper focuses on the results for the 5 K measurements of the GMR, exchange field and coercive field. The coercive field and exchange field are measured as a function of IrMn thickness and it was found that for IrMn layers /spl les/12 /spl Aring/, the coercive field is larger than the exchange field.
Domain names plan and schedule (1983)

This RFC outlines a plan and schedule for the implementation of domain
style names throughout the DDN/ARPA Internet community. The
introduction of domain style names will impact all hosts on the
DDN/ARPA Internet.
User-tailorable systems: pressing the issues with buttons (1990)

It is impossible to design systems which are appropriate for all users and all situations. We believe that a useful technique is to have end users tailor their systems to match their personal work practices. This requires not only systems which can be tailored, but a culture within which users feel in control of the system and in which tailoring is the norm. In a two-pronged research project we have worked closely with a group of users to develop a system to support tailoring and to help the users evolve a "tailoring culture". This has resulted in a flexible system based around the use of distributed on-screen Buttons to support a range of tailoring techniques.
In planta engineering of viral RNA replicons: Efficient assembly by recombination of DNA modules delivered by Agrobacterium (2004)

We have developed an efficient, versatile, and user-friendly viral engineering and expression system that is based on in planta assembly of functional viral vectors from separate pro-vector modules. With this new system, instead of supplying a plant cell with a complete viral vector as a mature viral particle, an RNA or a linear DNA molecule, we use agrobacteria to deliver various modules that are assembled inside the cell with the help of a site-specific recombinase. The resulting DNA is transcribed, and undesired elements such as recombination sites are spliced out, generating a fully functional RNA replicon. The proposed protocol allows us, by simply treating a plant with a mixture of two or more agrobacteria carrying specific prefabricated modules, to rapidly and inexpensively assemble and test multiple vector/gene combinations, without the need to perform the various engineering steps normally required with alternative protocols. The process described here is very fast (expression requires 3-4 days); it provides very high protein yield (up to 80% of total soluble protein); more than before, it is carried out using in vivo manipulations; it is based on prefabricated genetic modules that can be developed/upgraded independently; and it is inherently scalable.
Native-oxide defined ring contact for low threshold vertical-cavity lasers (1994)

Data are presented characterizing a new process for fabrication of vertical-cavity surface-emitting lasers based on the selective conversion of high Al composition epitaxial AlGaAs to a stable native oxide using ‘‘wet oxidation.’’ The native oxide is used to form a ring contact to the laser active region. The resulting laser active regions have dimensions of 8, 4, and 2 μm. The lowest threshold laser is achieved with the 8-μm active region, with a minimum threshold current of 225-μA continuous wave at room temperature.
De Novo Initiation of RNA Synthesis by the RNA-Dependent RNA Polymerase (NS5B) of Hepatitis C Virus (2000)

Hepatitis C virus (HCV) NS5B protein possesses an RNA-dependent RNA polymerase (RdRp) activity, a major function responsible for replication of the viral RNA genome. To further characterize the RdRp activity, NS5B proteins were expressed from recombinant baculoviruses, purified to near homogeneity, and examined for their ability to synthesize RNA in vitro. As a result, a highly active NS5B RdRp (1b-42), which contains an 18-amino acid C-terminal truncation resulting from a newly created stop codon, was identified among a number of independent isolates. The RdRp activity of the truncated NS5B is comparable to the activity of the full-length protein and is 20 times higher in the presence of Mn(2+) than in the presence of Mg(2+). When a 384-nucleotide RNA was used as the template, two major RNA products were synthesized by 1b-42. One is a complementary RNA identical in size to the input RNA template (monomer), while the other is a hairpin dimer RNA synthesized by a "copy-back" mechanism. Substantial evidence derived from several experiments demonstrated that the RNA monomer was synthesized through de novo initiation by NS5B rather than by a terminal transferase activity. Synthesis of the RNA monomer requires all four ribonucleotides. The RNA monomer product was verified to be the result of de novo RNA synthesis, as two expected RNA products were generated from monomer RNA by RNase H digestion. In addition, modification of the RNA template by the addition of the chain terminator cordycepin at the 3' end did not affect synthesis of the RNA monomer but eliminated synthesis of the self-priming hairpin dimer RNA. Moreover, synthesis of RNA on poly(C) and poly(U) homopolymer templates by 1b-42 NS5B did not require the oligonucleotide primer at high concentrations (>/=50 microM) of GTP and ATP, further supporting a de novo initiation mechanism. These findings suggest that HCV NS5B is able to initiate RNA synthesis de novo.