gebhart/patrepeval huggingface dataset:
Self-Assembly of Biocidal Nanotubes from a Single-Chain Diacetylene Amine Salt (2004)

We describe the facile two-step synthesis of nanotubes that form pure, well-defined, nanostructured materials. We have synthesized a secondary amine HBr salt as the headgroup of a single-chain diacetylenic lipid. This molecule can form a number of different self-assembled nanostructures in aqueous or organic solvents. In water, this lipid forms a monodisperse preparation of nanotubes at high yields. Partially dissolving a preparation of nanotubes dried from aqueous solution results in a remarkably organized structure that resembles a nanocarpet. Details of the nanotube structure were investigated by scanning electron microscopy, transmission electron microscopy, and small-angle X-ray spectroscopy. The aqueous nanotubes have a cross-sectional diameter of 89 nm. The walls of the tubes are an exquisitely uniform 27 nm thick and are shown to consist of five lipid bilayers with a repeat spacing of 57.8 A. The chemical structure of the material shows no chiral centers, but suspensions of the nanotubes in an aqueous medium show an unexpected circular dichroism signal. The versatility of this new material as a platform for nanostructure design and synthesis is enhanced by its biocidal activity. This antimicrobial activity along with the regularity the nanostructures will enhance the development of a range of applications from biosensors to artificial retinas.
Melanoma and sun exposure: Contrasts between intermittent and chronic exposure (1992)

The evidence relating cutaneous malignant melanoma to previous sun exposure is now very strong. Major northern hemisphere studies consistently show increases in melanoma in association with recreational and vacation activities related to intermittent sun exposure. These studies have also recorded amounts of sun exposure from such activities. Several studies suggest an increased risk related to short periods of intensive exposure in early adult life. In contrast, regular outdoor occupation confers a decreased risk in these same studies. Australian studies, in populations with much higher levels of total sun exposure, do not show such a clear distinction between intermittent and chronic exposure. The evidence is consistent with a complex relationship of melanoma risk to sun exposure, the risk being increased by intermittent exposure to levels of sun which are higher than normal for that individual, but no increased risk or even a decreased risk related to long term chronic exposure. Possible biological mechanisms for this complex relationship are discussed. In the Western Canada Melanoma Study the effects of occupational and recreational exposure are different in form and are independent. The increased risks seen with various measures of sun exposure do not appear to be systematically different for individuals who have a good tanning response as compared to individuals who do not.
Platelet-activating factor as an intercellular signal in neutrophil-dependent platelet activation (1992)

The role of platelet-activating factor (PAF) in heterotypic cell to cell interactions in a rabbit neutrophil-platelet mixture model was investigated. Platelets were exposed to each of three chemotactic agonists: PAF, leukotriene B4 (LTB4), or FMLP. Only PAF stimulated aggregation, [3H]serotonin secretion, and cytosolic Ca2+ mobilization in platelets alone. However, platelets were stimulated by LTB4 and FMLP in the presence of neutrophils. This neutrophil-dependent platelet activation was blocked by pretreatment of platelets with PAF receptor antagonists, and was prevented by desensitization of platelets to PAF. Furthermore, the time-course of platelet activation showed a positive correlation with PAF production by neutrophils stimulated with either LTB4 or FMLP. The PAF-mediated neutrophil-platelet interaction was dependent on direct cell to cell contact, as demonstrated by experiments in which the majority of newly formed PAF was neutrophil associated (rather than released). Platelet activation did not occur when the neutrophil-platelet mixture was not stirred, minimizing cell to cell contact, or when platelets were challenged with a cell-free supernatant prepared from neutrophils activated with LTB4 or FMLP. Finally, the neutrophil-platelet interaction was abolished by SC-49992, a peptidomimetic of the fibrinogen binding sequence Arg-Gly-Asp-Phe, indicating a Arg-Gly-Asp-specific recognition mechanism. Our results demonstrate that neutrophil-generated PAF plays a crucial role in neutrophil-dependent platelet activation in this model system. This type of intercellular signaling event may be important in certain inflammatory or thrombotic processes.
Porcine coronary imaging in vivo by optical coherence tomography (2000)

In this preliminary experiment, we have demonstrated that in vivo OCT imaging of normal coronary arteries, intimal dissections, and deployed stents is feasible, and allows identification of clinically relevant coronary artery morphology with high-resolution and contrast.
Tapasin Is Required for Efficient Peptide Binding to Transporter Associated with Antigen Processing (2000)

The transporter associated with antigen processing (TAP) binds peptides in its cytosolic part and subsequently translocates the peptides into the lumen of the endoplasmic reticulum (ER), where assembly of major histocompatibility complex (MHC) class I and peptide takes place. Tapasin is a subunit of the TAP complex and binds both to TAP1 and MHC class I. In the absence of tapasin, the assembly of MHC class I in the ER is impaired, and the surface expression is reduced. To clarify the function of tapasin in the processing of antigenic peptides, we studied the interaction of peptide and TAP, peptide transport across the membrane of the ER, and association of peptides with MHC class I molecules in the microsomes derived from tapasin mutant cell line 721.220, its sister cell line 721.221 expressing tapasin, and their HLA-A2 transfectants. The binding of peptides to TAP in tapasin mutant 721.220 cells was significantly diminished in comparison with 721.221 cells. Impaired peptide-TAP interaction resulted in a defective peptide transport in tapasin mutant 721.220 cells. Interestingly, despite the diminished peptide binding to TAP, the transport rate of TAP-associated peptides was not significantly altered in 721.220 cells. After transfection of tapasin cDNA into 721.220 cells, efficient peptide-TAP interaction was restored. Thus, we conclude that tapasin is required for efficient peptide-TAP interaction.
Cryptococcal Yeast Cells Invade the Central Nervous System via Transcellular Penetration of the Blood-Brain Barrier (2004)

Cryptococcal meningoencephalitis develops as a result of hematogenous dissemination of inhaled Cryptococcus neoformans from the lung to the brain. The mechanism(s) by which C. neoformans crosses the blood-brain barrier (BBB) is a key unresolved issue in cryptococcosis. We used both an in vivo mouse model and an in vitro model of the human BBB to investigate the cryptococcal association with and traversal of the BBB. Exposure of human brain microvascular endothelial cells (HBMEC) to C. neoformans triggered the formation of microvillus-like membrane protrusions within 15 to 30 min. Yeast cells of C. neoformans adhered to and were internalized by the HBMEC, and they crossed the HBMEC monolayers via a transcellular pathway without affecting the monolayer integrity. The histopathology of mouse brains obtained after intravenous injection of C. neoformans showed that the yeast cells either were associated with endothelial cells or escaped from the brain capillary vessels into the neuropil by 3 h. C. neoformans was found in the brain parenchyma away from the vessels by 22 h. Association of C. neoformans with the choroid plexus, however, was not detected during up to 10 days of observation. Our findings indicate that C. neoformans cells invade the central nervous system by transcellular crossing of the endothelium of the BBB.
Cannabinoids in cancer treatment: Therapeutic potential and legislation (2018)

The plant Cannabis sativa L. has been used as an herbal remedy for centuries and is the most important source of phytocannabinoids. The endocannabinoid system (ECS) consists of receptors, endogenous ligands (endocannabinoids) and metabolizing enzymes, and plays an important role in different physiological and pathological processes. Phytocannabinoids and synthetic cannabinoids can interact with the components of ECS or other cellular pathways and thus affect the development/progression of diseases, including cancer. In cancer patients, cannabinoids have primarily been used as a part of palliative care to alleviate pain, relieve nausea and stimulate appetite. In addition, numerous cell culture and animal studies showed antitumor effects of cannabinoids in various cancer types. Here we reviewed the literature on anticancer effects of plant-derived and synthetic cannabinoids, to better understand their mechanisms of action and role in cancer treatment. We also reviewed the current legislative updates on the use of cannabinoids for medical and therapeutic purposes, primarily in the EU countries. In vitro and in vivo cancer models show that cannabinoids can effectively modulate tumor growth, however, the antitumor effects appear to be largely dependent on cancer type and drug dose/concentration. Understanding how cannabinoids are able to regulate essential cellular processes involved in tumorigenesis, such as progression through the cell cycle, cell proliferation and cell death, as well as the interactions between cannabinoids and the immune system, are crucial for improving existing and developing new therapeutic approaches for cancer patients. The national legislation of the EU Member States defines the legal boundaries of permissible use of cannabinoids for medical and therapeutic purposes, however, these legislative guidelines may not be aligned with the current scientific knowledge.
The class 3 outer membrane protein (PorB) of Neisseria meningitidis: gene sequence and homology to the gonococcal porin PIA (1991)

Nuclear magnetic resonance spectroscopy, fast-atom bombardment mass spectrometry as well as various chemical degradations and chromatographic techniques were used to re-examine the structure of a highly immunoreactive glycolipid previously described in Mycobacterium tuberculosis (strain Canetti) as a 2,3-diacyl trehalose 2′-sulfate (labelled SL-IV). Ion exchange chromatography allowed the recognition of a neutral and an acidic glycolipid, indistinguishable on conventional silica gel. The neutral glycolipid was shown to be serologically identical to SL-IV and its structure was established as 2,3-diacyl trehalose. It corresponded to the non-chemically defined highly observed immunoreactive lipid previously recognized by other in M. tuberculosis (H37Rv).
Evidence for a Role of the Adenosine 5′-Triphosphate-Binding Cassette Transporter A1 in the Externalization of Annexin I from Pituitary Folliculo-Stellate Cells (2003)

Annexin 1 (ANXA1) has a well-demonstrated role in early delayed inhibitory feedback of glucocorticoids in the pituitary. ANXA1 is located in folliculo-stellate (FS) cells, and glucocorticoids act on these cells to externalize and stimulate the synthesis of ANXA1. However, ANXA1 lacks a signal sequence so the mechanism by which ANXA1 is externalized from FS cells was unknown and has been investigated. The ATP-binding cassette (ABC) transporters are a large group of transporters with varied roles that include the externalization of proteins. Glucocorticoid-induced externalization of ANXA1 from an FS cell line (TtT/GF) and rat anterior pituitary was blocked by glyburide, which inhibits ABC transporters. Glyburide also blocked the glucocorticoid inhibition of forskolin-stimulated ACTH release from pituitary tissue in vitro. RT-PCR revealed mRNA and Western blotting demonstrated protein for the ATP binding cassette A1 (ABCA1) transporter in mouse FS, TtT/GF, and A549 lung adenocarcinoma cells from which glucocorticoids also induce externalization of ANXA1. In TtT/GF cells, immunofluorescence labeling revealed a near total colocalization of cell surface ANXA1 and ABCA1. We conclude that ANXA1, which mediates the early delayed feedback of glucocorticoids in the anterior pituitary, is externalized from FS cells by an ABC transporter and that the ABCA1 transporter is a likely candidate.
Development of a Micropump for Microelectronic Cooling (1996)

Abstract To demonstrate a system integration process for Micro-Electro-Mechanical Systems (MEMS), we are building an active cooling MEMS unit for microelectronics applications. This integrated unit will incorporate a micropump, temperature sensors, microchannels, and heat exchange devices into a single unit. The first phase of this research project is to develop and test a micropump capable of moving the working fluid within the integrated device. This paper will discuss the design, development, testing, and evaluation of a micropump concept. The micropump which was developed is an electrohydrodynamic (EHD) injection pump. Fabrication of the pump was accomplished using laser micromachining technology, and two initial designs were examined for full fabrication. The first design has two silicon parts stacked vertically on top of each other. Gold is deposited on one side of each stacked plate to serve as electrodes for the electrohydrodynamic pump. A Nd:YAG laser is used to drill an array of circular holes in the “well” region of both silicon parts, leaving an open pathway for fluid movement. Next the silicon parts are aligned and bonded together, thus becoming a EHD pump. Fluid flow has been observed when an electric voltage is applied across the electrodes. The second design has the silicon parts which contain the flow grid oriented “back-to-back” and bonded together. This “back-to-back” design has a shorter grid distance between the anode and cathode plates so that a smaller voltage is required for pumping. Preliminary results from laboratory experiments have demonstrated that this EHD micropump design can achieve a pressure head of about 287 Pa with an applied voltage of 120 V.
Molecular and insecticidal characterization of a Bacillus thuringiensis strain isolated during a natural epizootic (2000)

A new Bacillus thuringiensis strain belonging to the serovar aizawai was isolated from a dead larva of the lepidopteran Mythimna loreyi collected in a corn crop in Spain during a natural epizootic. This strain, which was named Leapi01, was compared with the kurstaki and aizawai strains isolated from Dipel(R) and Xentari(R), by electron microscopy, SDS-PAGE, plasmid pattern, PCR and insecticidal activity. This strain showed similar morphological and biochemical characteristics to the standard strains. The content in cry genes of Leapi01 was analysed with a set of general and specific primers recognizing most of the cry genes reported to date. DNA amplification was obtained with primers corresponding to six genes and, to clearly determine the identity of the genes, the amplified fragments were sequenced and corresponded to cry1Aa, cry1Ab, cry1Ca, cry1Da, cry2Ab and cry1Ia. However, the proteins encoded by two of these genes, Cry2 and Cry1I, were not detected in the SDS-PAGE of the purified parasporal bodies. The insecticidal activity of Leapi01 was determined by bioassays against two Lepidoptera species, Helicoverpa armigera and Spodoptera littoralis, that were found to be very susceptible to Leapi01 purified crystals. Since two of the cry genes identified in Leapi01 appear to be silent, other factors may be involved in the toxicity of the strain. As a result of this study, the potential of Leapi01 as biological control agent is discussed, with special emphasis on the high toxicity and relatively broad spectrum activity compared with two B. thuringiensis strains that are the active ingredients of commercial preparations commonly used as bioinsecticides.
Transplantation of Mesenchymal Stem Cells to Prevent Radiation-induced Intestinal Injury in Mice (2010)

The effective treatments of radiation-induced intestinal injury are currently unavailable. Developing new treatments for radiation-induced intestinal injury is thus important. The present study investigated whether transplantation of mesenchymal stem cells (MSCs) is able to prevent radiation-induced intestinal injury. Intestines of female nude mice (ICR nu/nu) were irradiated at a single dose of 30 Gy. Transplantation of male MSCs (C57BL/6) was then immediately performed into the walls of irradiated intestine by direct injection for the irradiation + MSCs group. Mice were weighed daily and survival was recorded for 13 days after irradiation. From 13 to 27 days after irradiation, intestines of mice were obtained in order to assay histological changes by staining with hematoxylin-eosin and Masson trichrome. Mean body weight of the irradiation + MSC group was significantly higher than that of the irradiation-only group from 8 days after irradiation. In addition, survival rates were significantly higher in the irradiation + MSC group than for the irradiation-only group from 5 days after irradiation. Histological observation revealed that intestines of irradiation + MSC-transplanted mice were thick in the submucosal and muscle layers, and had almost fully recovered from radiation-induced intestinal injury at day 27. Specifically, ulcerated areas in the intestines of the irradiation + MSC-transplanted mice were smaller by 13 days after irradiation and were fewer in numbers at 27 days when compared with the irradiation-only group. Our results suggest that transplanted MSCs may play an important role in preventing radiation-induced injury and may offer a novel method to treat radiation-induced intestinal injury.
Selective palladium-catalyzed vinylic substitutions with bromoiodo aromatics (1979)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSelective palladium-catalyzed vinylic substitutions with bromoiodo aromaticsJoseph E. Plevyak, James E. Dickerson, and Richard F. HeckCite this: J. Org. Chem. 1979, 44, 23, 4078–4080Publication Date (Print):November 1, 1979Publication History Published online1 May 2002Published inissue 1 November 1979https://pubs.acs.org/doi/10.1021/jo01337a012https://doi.org/10.1021/jo01337a012research-articleACS PublicationsRequest reuse permissionsArticle Views872Altmetric-Citations62LEARN 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
A microfluidic chip-compatible bioassay based on single-molecule detection with high sensitivity and multiplexing (2010)

Many applications in pharmaceutical development, clinical diagnostics, and biological research demand rapid detection of multiple analytes (multiplexed detection) in a minimal volume. This need has led to the development of several novel array-based sensors. The most successful of these so far have been suspension arrays based on polystyrene beads. However, the 5 microm beads used for these assays are incompatible with most microfluidic chip technologies, mostly due to clogging problems. The challenge, then, is to design a detection particle that has high information content (for multiplexed detection), is compatible with miniaturization, and can be manufactured easily at low cost. DNA is a solid molecular wire that is easily produced and manipulated, which makes it a useful material for nanoparticles. DNA molecules are very information-rich, readily deformable, and easily propagated. We exploit these attributes in a suspension array sensor built from specialized recombinant DNA, Digital DNA, that carries both specific analyte-recognition units, and a geometrically encoded identification pattern. Here we show that this sensor combines high multiplexing with high sensitivity, is biocompatible, and has sufficiently small particle size to be used within microfluidic chips that are only 1 microm deep. We expect this technology will be the foundation of a broadly applicable technique to identify and quantitate proteins, nucleic acids, viruses, and toxins simultaneously in a minimal volume.
Intracellular regulation of tumor necrosis factor–related apoptosis-inducing ligand–induced apoptosis in human multiple myeloma cells (2002)

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL, Apo2 ligand) effectively kills multiple myeloma (MM) cells in vitro irrespective of refractoriness to dexamethasone and chemotherapy. Because clinical trials with this anticancer agent are expected shortly, we investigated the signaling pathway of TRAIL-induced apoptosis in MM. We detected rapid cleavage of caspases-8, -9, -3, and -6, as well as the caspase substrates poly(ADP-ribose) polymerase (PARP) and DNA fragmentation factor-45 (DFF45), but not caspase-10, upon TRAIL treatment in sensitive MM cells, pointing to caspase-8 as the apical caspase of TRAIL signaling in MM cells. These phenomena were not observed or were significantly delayed in TRAIL-resistant MM cells, suggesting that resistance may arise from inhibition at the level of caspase-8 activation. Higher levels of expression for various apoptosis inhibitors, including FLICE-inhibitory protein (FLIP), and lower procaspase-8 levels were present in TRAIL-resistant cells and sensitivity was restored by the protein synthesis inhibitor cycloheximide (CHX) and the protein kinase C (PKC) inhibitor bisindolylmaleimide (BIM), which both lowered FLIP and cellular inhibitor of apoptosis protein-2 (cIAP-2) protein levels. Forced expression of procaspase-8 or FLIP antisense oligonucleotides also sensitized TRAIL-resistant cells to TRAIL. Moreover, the cell permeable nuclear factor (NF)-kappaB inhibitor SN50, which sensitizes TRAIL-resistant cells to TRAIL, also inhibited cIAP2 protein expression. Finally, CHX, BIM, and SN50 facilitated the cleavage and activation of procaspase-8 in TRAIL-resistant cells, confirming that inhibition of TRAIL-induced apoptosis occurs at this level and that these agents sensitize MM cells by relieving this block. Our data set a framework for the clinical use of approaches that sensitize MM cells to TRAIL by agents that inhibit FLIP and cIAP-2 expression or augment caspase-8 activity.
The physics handbook: fundamentals and key equations (2007)

Preface. Physical Constants. 1 Lagrangian and Hamiltonian Formulations. 2 Central Forces. 3 Rigid Bodies. 4 Oscillations and Vibrations. 5 Canonical Transformations. 6 Non-Linear Dynamics and Chaos. 7 Relativity. 8 Thermodynamics. 9 Statistical Mechanics and Distribution Functions. 10 Electrostatics and Magnetostatics. 11 Multipoles and Media. 12 Relativistic Electrodynamics. 13 Wave Propagation. 14 Optics. 15 Radiation. 16. Collision. 17 Angular Momentum. 18. Matrix Formulation of Quantum Mechanics. 19 Schrodinger Equation. 20 One-Dimensional Quantum Systems. 21 Atoms. 22 Perturbation Theory. 23 Fluids and Solids. 24 Conduction in Solids. 25 Nuclei. 26 Elementary Particles. 27 Mathematical Physics: Tensors and Matrices.