gebhart/patrepeval huggingface dataset:
MicroRNA: Biogenesis, Function and Role in Cancer (2010)

MicroRNAs are small, highly conserved non-coding RNA molecules involved in the regulation of gene expression. MicroRNAs are transcribed by RNA polymerases II and III, generating precursors that undergo a series of cleavage events to form mature microRNA. The conventional biogenesis pathway consists of two cleavage events, one nuclear and one cytoplasmic. However, alternative biogenesis pathways exist that differ in the number of cleavage events and enzymes responsible. How microRNA precursors are sorted to the different pathways is unclear but appears to be determined by the site of origin of the microRNA, its sequence and thermodynamic stability. The regulatory functions of microRNAs are accomplished through the RNA-induced silencing complex (RISC). MicroRNA assembles into RISC, activating the complex to target messenger RNA (mRNA) specified by the microRNA. Various RISC assembly models have been proposed and research continues to explore the mechanism(s) of RISC loading and activation. The degree and nature of the complementarity between the microRNA and target determine the gene silencing mechanism, slicer-dependent mRNA degradation or slicer-independent translation inhibition. Recent evidence indicates that P-bodies are essential for microRNA-mediated gene silencing and that RISC assembly and silencing occurs primarily within P-bodies. The P-body model outlines microRNA sorting and shuttling between specialized P-body compartments that house enzymes required for slicer -dependent and -independent silencing, addressing the reversibility of these silencing mechanisms. Detailed knowledge of the microRNA pathways is essential for understanding their physiological role and the implications associated with dysfunction and dysregulation.
Antigen expression of cord blood derived stem cells under osteogenic stimulation in vitro (2007)

Tissue engineering strategies have become a promising option for treating musculoskeletal defects in future. Cord blood includes mesenchymal stem cells which are able to differentiate into several cell lines under lineage specific stimulation including osteoblasts, chondroblasts and adipoblasts. In this study the antigen pattern of cord blood stem cells cultivated onto a porous porcine collagen I/III scaffold is investigated. The cultures were stimulated with osteogenic mixture (dexamethasone, ascorbic acid, glycerolphosphatate [DAG]) over 21days in vitro. The following antigens and markers served for immuncytochemical evaluation: bone sialoprotein, osteocalcin, osteonectin, osteopontin, cartilage proteoglycan, chondrogenic oligomeric matrix protein, collagen I/II/III/X, CD13, CD 31, CD34, CD44, CD45, CD105, fibroblast growth factor receptor 2, vascular endothelial growth factor, vimentin and von-Kossa and HE stainings. We showed that a collagen I/III scaffold is an appropriate cellular carrier for cord blood progenitor cells and allows for an osteoblastic differentiation. Moreover there were differences in antigen pattern, dependent on the location of the adherent cells. CD105 and VEGF were only expressed at the bottom of the biomaterial. Future investigations should show the role of cytomechanical forces in the differentiation of cord blood derived progenitor cells and also if a cell-loaded collagen I/III scaffold is appropriate to stimulate bone regeneration in vivo.
The magnetosome membrane protein, MmsF, is a major regulator of magnetite biomineralization in Magnetospirillum magneticum AMB‐1 (2012)

Magnetotactic bacteria (MTB) use magnetosomes, membrane-bound crystals of magnetite or greigite, for navigation along geomagnetic fields. In Magnetospirillum magneticum sp. AMB-1, and other MTB, a magnetosome gene island (MAI) is essential for every step of magnetosome formation. An 8-gene region of the MAI encodes several factors implicated in control of crystal size and morphology in previous genetic and proteomic studies. We show that these factors play a minor role in magnetite biomineralization in vivo. In contrast, MmsF, a previously uncharacterized magnetosome membrane protein encoded within the same region plays a dominant role in defining crystal size and morphology and is sufficient for restoring magnetite synthesis in the absence of the other major biomineralization candidates. In addition, we show that the 18 genes of the mamAB gene cluster of the MAI are sufficient for the formation of an immature magnetosome organelle. Addition of MmsF to these 18 genes leads to a significant enhancement of magnetite biomineralization and an increase in the cellular magnetic response. These results define a new biomineralization protein and lay down the foundation for the design of autonomous gene cassettes for the transfer of the magnetic phenotype in other bacteria.
Chimeric papillomavirus virus-like particles induce a murine self-antigen-specific protective and therapeutic antitumor immune response (1999)

The use of chimeric virus-like particles represents a new strategy for delivering tumor antigens to the immune system for the initiation of antitumor immune responses. Immunization of DBA/2 mice with the P1A peptide derived from the P815 tumor-associated antigen P1A induced specific T-cell tolerance, resulting in progression of a regressor P815 cell line in all animals. However, immunization with a human papillomavirus type 16 L1 virus-like particle containing the P1A peptide in the absence of adjuvant induced a protective immune response in mice against a lethal tumor challenge with a progressor P815 tumor cell line. Additionally, we demonstrated that these chimeric virus-like particles could be used therapeutically to suppress the growth of established tumors, resulting in a significant survival advantage for chimeric virus-like particle-treated mice compared with untreated control mice. Chimeric virus-like particles can thus be used as a universal delivery vehicle for both tolerizing and antigenic peptides to induce a strong protective and therapeutic antigen-specific antitumor immune response.
Refinement of Model Parameters of Radionuclide Transport with Surface Water while Assimilation of Observational Data (2003)

The problem of forecast refinement and model parameters of radionuclide migration with surface water by measuring data is considered. We assume that only a priori estimations of the initial state and model parameters are known. This problem is reduced to an optimization problem with a quadratic quality functional in the vicinity of a priori estimations of the initial state and model parameters. We have proved the possibility of one-valued solvability of direct and adjoint problems for the state function of a model. Differential properties of the quality functional are investigated and the necessary conditions of its minimum are found. For weight functions of the quality functional the sufficient conditions of existence of a unique stationary point on a set of the feasible values of model parameters are obtained.
Observation of quasiperiodic dynamics in a one-dimensional quantum walk of single photons in space (2014)

We realize quasi-periodic dynamics of a quantum walker over 2.5 quasi-periods by realizing the walker as a single photon passing through a quantum-walk optical-interferometer network. We introduce fully controllable polarization-independent phase shifters in each optical path to realize arbitrary site-dependent phase shifts, and we employ large clear-aperture beam displacers, while maintaining high-visibility interference, to enable reaching 10 quantum-walk steps. By varying the half-wave-plate setting, we control the quantum-coin bias thereby observing a transition from quasi-periodic dynamics to ballistic diffusion.
Effects of demineralized bone matrix on proliferation and osteogenic differentiation of mesenchymal stem cells from human umbilical cord. (2006)

Mesenchymal progenitor cells derived from umbilical cord could differentiate along an osteogenic lineage and thus provide an alternative source for cell-based therapies and tissue engineering strategies.
Recombinant Human Growth Hormone to Treat HIV-Associated Adipose Redistribution Syndrome (2007)

Background: HIV-associated adipose redistribution syndrome (HARS) is an HIV-associated disorder characterized by excess truncal fat, including visceral adipose tissue (VAT). Methods: From baseline to week 12 in this randomized, double-blind, placebo (PL)-controlled, multicenter trial investigating effects of recombinant human growth hormone (r-hGH; Serostim; EMD Serono Inc., Rockland, MA) in patients with HARS, 325 received induction (4 mg/d of r-hGH) or PL. At week 12, patients who initially received induction were rerandomized to 2 mg of r-hGH on alternate days (maintenance) or PL to week 36. Patients who initially received PL later received 4 mg/d of r-hGH. Change in VAT was the primary outcome. Key secondary outcomes included changes in non-high-density lipoprotein cholesterol (non-HDL-C) and limb fat. Results: At week 12, induction therapy resulted in decreased VAT (−32.6 vs. 0.5 cm2; P < 0.001), limb fat (−0.4 vs. 0.2 kg; P < 0.001), and non-HDL-C (−13.0 vs. −2.8 mg/dL; P = 0.023) compared with PL. On r-hGH induction-maintenance (baseline to week 36), patients sustained losses in VAT and trunk fat but not losses of subcutaneous fat in the abdomen or limbs. Also, non-HDL-C remained significantly decreased on r-hGH but not on PL maintenance. Conclusions: In patients with HARS, r-hGH induction-maintenance therapy produces greater relative losses of VAT and trunk fat than of subcutaneous fat and also has beneficial effects on the lipid profile.
Genomic organization and transcriptional regulation of the RANTES chemokine gene. (1993)

RANTES is a member of a large supergene family of pro-inflammatory cytokines called CC chemokines that appear to play a fundamental role in inflammatory processes. The RANTES protein causes release of histamine from basophils and is a chemoattractant for CD45RO/CD4+ "memory" T lymphocytes, monocytes, and eosinophils. Although expression of RANTES was first thought to be limited to activated T cells, recent data have shown that it is produced by a variety of tissue types in response to specific stimuli. RANTES mRNA is expressed late (3 to 5 days) after activation of resting T cells whereas in fibroblasts, renal epithelial and mesangial cells, RANTES mRNA is quickly up-regulated by TNF-alpha stimulation. In order to gain a better understanding of the molecular mechanisms that regulate expression of the RANTES locus, we have characterized the RANTES gene and determined a putative promoter region. The RANTES gene spans approximately 7.1 kb and is composed of three exons of 133, 112 and 1075 bases and two introns of approximately 1.4 and 4.4 kb with the position of intron/exon boundaries conserved relative to the other CC chemokine family members. Approximately 1 kb of DNA from the immediate 5' upstream region of RANTES was sequenced and found to contain a large number of potential consensus elements for specific T cell/hemopoietic, myeloid, muscle, and ubiquitously expressed DNA-binding factors. RANTES-promoter-luciferase gene fusion assays demonstrate high levels of reporter gene activity in a "mature" T cell line Hut78, the erythroleukemic cell line HEL, and the rhabdomyosarcoma cell line RD, with little or no activity in the "early" T cell line Jurkat, the gamma delta T cell line PEER, the thymic tumor Molt4, or the pre-erythroid cell line K562. Deletion analysis of the promoter region indicates that different transcriptional mechanisms control expression of RANTES in the various tissues studied.
Researches on a Novel Method for Fluorination of Halopyridazine Derivatives in Ionic Liquid (2007)

Abstract A novel method for fluorination of halopyridazine derivatives with potassium fluoride was performed using a green chemistry procedure, including ionic liquid as an environmentally benign reaction medium and microwave irradiation with high yield.
Load transfer and deformation mechanisms in carbon nanotube-polystyrene composites (2000)

Multiwall carbon nanotubes have been dispersed homogeneously throughout polystyrene matrices by a simple solution-evaporation method without destroying the integrity of the nanotubes. Tensile tests on composite films show that 1 wt % nanotube additions result in 36%–42% and ∼25% increases in elastic modulus and break stress, respectively, indicating significant load transfer across the nanotube-matrix interface. In situ transmission electron microscopy studies provided information regarding composite deformation mechanisms and interfacial bonding between the multiwall nanotubes and polymer matrix.
Chimie Douce Approaches to the Synthesis of Metastable Oxide Materials (1995)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChimie Douce Approaches to the Synthesis of Metastable Oxide MaterialsJ. GopalakrishnanCite this: Chem. Mater. 1995, 7, 7, 1265–1275Publication Date (Print):July 1, 1995Publication History Published online1 May 2002Published inissue 1 July 1995https://pubs.acs.org/doi/10.1021/cm00055a001https://doi.org/10.1021/cm00055a001research-articleACS PublicationsRequest reuse permissionsArticle Views2733Altmetric-Citations450LEARN 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
Pharmacologic evaluation of megestrol acetate oral suspension in cachectic AIDS patients. (1994)

The objective of our study was to define the pharmacokinetics and pharmacodynamics of megestrol acetate in patients with human immunodeficiency virus (HIV) infection. A new suspension formulation of megestrol acetate (40 mg/ml) was administered as a single oral dose of 800 mg per day in an open label pharmacokinetic study for 21 days. On day 21 of therapy, patients were evaluated for changes in body weight and plasma samples were obtained for steady-state pharmacokinetic analysis. Ten HIV-infected men with an involuntary weight loss of > 10% baseline were evaluated. A high degree of interpatient variability in megestrol acetate pharmacokinetics was observed, with an 8- and 5-fold range in the rate and extent of absorption, respectively. All patients reported an increase in appetite, and 8 of 10 patients gained weight by 3 weeks; the median change in weight in all patients at 3 weeks was 1.8-kg gain (range: 2.3-kg loss to 6.4-kg gain). The two patients who did not gain weight had the lowest area under the curve (AUC), Cmax, and Cmin values. A statistically significant correlation between the ratio of body weight at 3 weeks/initial weight (weight index) and the percentage of the 24-h dosing interval that megestrol acetate concentrations exceeded a 300-ng/ml threshold was observed. These data indicate variable levels of systemic exposure to drug following a fixed dose of a suspension formulation of megestrol acetate. Increase in weight during the early stages of megestrol acetate therapy is related to the extent of in vivo drug exposure above a threshold concentration.(ABSTRACT TRUNCATED AT 250 WORDS)
Curcumin suppresses p38 mitogen-activated protein kinase activation, reduces IL-1β and matrix metalloproteinase-3 and enhances IL-10 in the mucosa of children and adults with inflammatory bowel disease (2009)

Inflammatory bowel disease (IBD) is a major source of morbidity in children and adults. Its incidence is rising, particularly in young people. IBD carries a lifelong risk of cancer, which is proportional to disease duration. Drug and surgical treatments rarely offer cure and often carry a high side effect burden. Dietary therapy is highly effective in Crohn's disease. For these reasons, there is much interest in developing novel dietary treatments in IBD. Curcumin, a component of the spice turmeric, and an anti-inflammatory and anti-cancer agent, shows preclinical and clinical potential in IBD. Its mechanisms of action are unknown. Our aim was to assess the effect of curcumin on key disease mediators p38 mitogen-activated protein kinase (MAPK), IL-1β, IL-10 and matrix metalloproteinase-3 (MMP-3) in the gut of children and adults with IBD. Colonic mucosal biopsies and colonic myofibroblasts (CMF) from children and adults with active IBD were cultured ex vivo with curcumin. p38 MAPK, NF-κB and MMP-3 were measured by immunoblotting. IL-1β and IL-10 were measured by ELISA. We show reduced p38 MAPK activation in curcumin-treated mucosal biopsies, enhanced IL-10 and reduced IL-1β. We demonstrate dose-dependent suppression of MMP-3 in CMF with curcumin. We conclude that curcumin, a naturally occurring food substance with no known human toxicity, holds promise as a novel therapy in IBD.
TLR3 activation efficiency by high or low molecular mass poly I:C (2012)

Toll-like receptor 3 (TLR3) plays a critical role in initiating type I IFN-mediated innate immunity against viral infections. TLR3 recognizes various forms of double stranded (ds) RNA, including viral dsRNA and a synthetic mimic of dsRNA, poly I:C, which has been used extensively as a TLR3 ligand to induce antiviral immunity. The activation efficiency of TLR3 by poly I:C is influenced by various factors, including size of the ligands, delivery methods and cell types. In this study, we examined the stimulatory effect of two commercially-available poly I:Cs [high molecular mass (HMM) and low molecular mass (LMM)] on TLR3 activation in various human cell types by determining the induction of type I and type III IFNs, as well as the antiviral effect. We demonstrated that the direct addition of both HMM- and LMM-poly I:C to the cultures of primary macrophages or a neuroplastoma cell line could activate TLR3. However, the transfection of poly I:C was necessary to induce TLR3 activation in other cell types studied. In all the cell lines tested, the efficiency of TLR3 activation by HMM-poly I:C was significantly higher than that by LMM-poly I:C. These observations indicate the importance and necessity of developing effective TLR3 ligands for antiviral therapy.
Enzyme Immobilization on Porous Silicon Surfaces (2004)

β‐Glucuronidase enzymes have been attached to a porous silicon surface through a direct silicon–carbon bond based linking system (see Figure). The attached enzymes display high activity and the photoluminescent (PL) properties and surface stability of the porous silicon are retained. Quenching of the PL is observed upon enzymatic breakdown of the substrate, leading to the possibility of a new class of chemical and biological sensors.
Cerebral desaturation during cardiac arrest: Its relation to arrest duration and left ventricular pump function* (2009)

These findings demonstrate that severely compromised left ventricular pump function is associated with diminished rSO2. As these patients seem to be more susceptible to critical desaturations, they may be prone to severe tissue hypoxemia unless adequate oxygen delivery is reestablished rapidly. This may contribute to the poor neurologic outcome after successful resuscitation in patients with LVEF <30%.
High incidence of disease recurrence in the brain and leptomeninges in patients with nonsmall cell lung carcinoma after response to gefitinib (2005)

The CNS was a frequent site of disease recurrence in patients with NSCLC after an initial response to gefitinib, regardless of disease control in the lungs. Patients should be carefully monitored for neurologic symptoms. Intrinsic resistance of metastatic clones, incomplete CNS penetrance of the drug, and longer survival are possible explanations for this high incidence.
K-ras oncogene mutations in sporadic colorectal cancer in The Netherlands Cohort Study (2003)

Activation of K-ras oncogene has been implicated in colorectal carcinogenesis, being mutated in 30-60% of the adenocarcinomas. In this study, 737 incident colorectal cancer (CRC) patients, originating from 120 852 men and women (55-69 years at baseline) participating in the Netherlands Cohort Study (NLCS), were studied in order to evaluate subgroups with respect to K-ras mutation status. Mutation analysis of the exon 1 fragment of the K-ras oncogene, spanning codons 8-29, was performed on archival colorectal adenocarcinoma samples of all patients using macrodissection, nested PCR and direct sequencing of purified fragments. The method of mutation detection was validated by the confirmation of reported K-ras status in CRC cell lines, a good correlation between fresh-frozen and routinely fixed, paraffin-embedded tissue, a detection limit of 5% mutated DNA and a good reproducibility. Various types of K-ras mutations were evaluated with respect to tumour sub-localization, Dukes' stage and tumour differentiation. In 37% (271/737) of the patients, the exon 1 fragment of K-ras gene was found to be mutated. The predominant mutations are G>A transitions and G>T transversions, and codons 12 and 13 are the most frequently affected codons. Patients with a rectal tumour were found to have the highest frequency of G>T transversions as compared with patients with a colon or rectosigmoid tumour. This difference appeared to be confined to women with a rectal tumour harbouring G>T transversions. No significant differences were observed for Dukes' stage with respect to types of K-ras mutation, which does not support direct involvement of the K-ras oncogene in adenocarcinoma progression. The equal distribution of K-ras mutations among cases with or without a family history of colorectal cancer argues against an important role for this mutation in familial colorectal cancer, and could imply that K-ras mutations are more probably involved in environmental mechanisms of colorectal carcinogenesis.
An ultrastructural analysis of plasma membrane in the U18666A cataract. (1988)

Because the cholesterol concentration of lens fiber cell membrane in general and lens intercellular junctions in particular is comparatively high, it is likely that it plays a major role in maintaining these structures. In addition, the high concentration of cholesterol in fiber cell membrane is also likely to influence membrane fluidity. Subcutaneous injections of U18666A (3 beta-(2-diethylaminoethoxy) androst-5-en-17-one HCl) into rats effects: (1) a blockade of sterolgenesis in the lens; (2) a depletion of lens fiber cell membrane cholesterol; and (3) the development of irreversible nuclear cataracts. In the present study we have analyzed the ultrastructure of lens fiber cell membrane in adult rats, these by the freeze-etch technique. Whereas it has been previously demonstrated that intercellular junctions comprise approximately one-third of the intermediate cortical fiber cell membrane in adult rats, these junctions were completely absent between comparable fiber cells taken from opaque regions of the U18666A cataractous lenses. There was also a concomitant increase in the extracellular space between the opaque fiber cells and a substantial redistribution of intramembrane proteins in the exoplasmic and protoplasmic faces of these cells. These findings support a "hypothesis" that inhibition of endogenous lens cholesterol production leads to damage and/or degeneration of lens fiber cell membrane in general and in intercellular junctions in particular, resulting in the production of an irreversible nuclear cataract.