gebhart/patrepeval huggingface dataset:
Microcin E492, a channel-forming bacteriocin from Klebsiella pneumoniae , induces apoptosis in some human cell lines (2002)

The cytotoxic effect of microcin E492, a low-molecular-mass channel-forming bacteriocin (7,887 Da) produced by a strain of Klebsiella pneumoniae, was characterized in HeLa cells. At low (5 microg/ml) and intermediate (10 microg/ml) concentrations, microcin E492 induced biochemical and morphological changes typical of apoptosis, such as cell shrinkage, DNA fragmentation, extracellular exposure of phosphatidylserine, caspase activation, and loss of mitochondrial membrane potential. Treatment with zVAD-fmk, a general caspase inhibitor, completely blocked the cytotoxic effect of this bacteriocin. At higher microcin concentrations (>20 microg/ml) a necrotic phenotype was observed. Induction of apoptosis by microcin E492 was associated with the release of calcium from intracellular stores, probably after microcin-triggered ion channel formation. Microcin E492 also presented a cytotoxic effect on Jurkat and RJ2.25 cells, but had no effect on KG-1 cells nor on a primary culture of human tonsil endothelial cells, suggesting that there is a specific interaction of the bacteriocin with components of the target cell surface. This report describes a bacteriocin that has the capacity to induce apoptosis in human cell lines.
The Superconductivity of Some Intermetallic Compounds (1962)

The W-Os, Re-W, Re-Mo, Re-Hf, and Mo-Hf binary systems were investigated for superconductivity down to 1°K. Several new superconducting regions were found with the most significant occurring in the primary and terminal solid-solution alloys. The occurrence of superconductivity in the β-phase field of the Re-Hf and Mo-Hf binaries indicates a possible explanation for the spurious superconducting effects sometimes observed in elemental hafnium.
HGF, SDF-1, and MMP-9 are involved in stress-induced human CD34+ stem cell recruitment to the liver (2003)

Hematopoietic stem cells rarely contribute to hepatic regeneration, however, the mechanisms governing their homing to the liver, which is a crucial first step, are poorly understood. The chemokine stromal cell-derived factor-1 (SDF-1), which attracts human and murine progenitors, is expressed by liver bile duct epithelium. Neutralization of the SDF-1 receptor CXCR4 abolished homing and engraftment of the murine liver by human CD34+ hematopoietic progenitors, while local injection of human SDF-1 increased their homing. Engrafted human cells were localized in clusters surrounding the bile ducts, in close proximity to SDF-1-expressing epithelial cells, and differentiated into albumin-producing cells. Irradiation or inflammation increased SDF-1 levels and hepatic injury induced MMP-9 activity, leading to both increased CXCR4 expression and SDF-1-mediated recruitment of hematopoietic progenitors to the liver. Unexpectedly, HGF, which is increased following liver injury, promoted protrusion formation, CXCR4 upregulation, and SDF-1-mediated directional migration by human CD34+ progenitors, and synergized with stem cell factor. Thus, stress-induced signals, such as increased expression of SDF-1, MMP-9, and HGF, recruit human CD34+ progenitors with hematopoietic and/or hepatic-like potential to the liver of NOD/SCID mice. Our results suggest the potential of hematopoietic CD34+/CXCR4+cells to respond to stress signals from nonhematopoietic injured organs as an important mechanism for tissue targeting and repair.
Automated classification of parenchymal patterns in mammograms (1998)

A method for automated determination of parenchymal patterns in mammograms has been developed that is insensitive to changes in the mammographic imaging technique. The method was designed to study the relation between breast cancer risk and changes of mammographic density. It includes a new method for automatic segmentation of the pectoral muscle in oblique mammograms, based on application of the Hough transform. The technique developed for classification of parenchymal patterns is based on a distance transform that subdivides the breast tissue area into regions in which distance to the skin line is approximately equal. Features are calculated from grey level histograms computed in these regions. In this way, dependency on varying tissue thickness in the peripheral zone of the breast is minimized. Additional features represent differences between tissue projected in pectoral and breast area. Robustness and classification performance were studied on a test set of 615 digitized mammograms, applying a kNN classifier and leave-one-out for training. Using four density categories in 67% of the cases an exact agreement was obtained with a subjective classification made by a radiologist. The number of cases for which classifications of the radiologist and the program differed by more that one category was only 2%. For more recent mammograms, recorded after 1991, an exact agreement of 80% was obtained.
Structure and Function of Bacterial Super-Biosystem Responsible for Import and Depolymerization of Macromolecules (2005)

Generally, when microbes assimilate macromolecules, they incorporate low-molecular-weight products derived from macromolecules through the actions of extracellular degrading enzymes. However, a Gram-negative bacterium, Sphingomonas sp. A1, has a smart biosystem for the import and depolymerization of macromolecules. The bacterial cells directly incorporate a macromolecule, alginate, into the cytoplasm through a "superchannel", as we named it. The superchannel consists of a pit on the cell surface, alginate-binding proteins in the periplasm, and an ATP-binding cassette transporter in the inner membrane. Cytoplasmic polysaccharide lyases depolymerize alginate into the constituent monosaccharides. Other than the proteins characterized so far, novel proteins (e.g., flagellin homologs) have been found to be crucial for the import and depolymerization of alginate through genomics- and proteomics-based identification, thus indicating that the biosystem is precisely constructed and regulated by diverse proteins. In this review, we focus on the structure and function of the bacterial biosystem together with the evolution of related proteins.
DNA glycosylases: in DNA repair and beyond (2011)

The base excision repair machinery protects DNA in cells from the damaging effects of oxidation, alkylation, and deamination; it is specialized to fix single-base damage in the form of small chemical modifications. Base modifications can be mutagenic and/or cytotoxic, depending on how they interfere with the template function of the DNA during replication and transcription. DNA glycosylases play a key role in the elimination of such DNA lesions; they recognize and excise damaged bases, thereby initiating a repair process that restores the regular DNA structure with high accuracy. All glycosylases share a common mode of action for damage recognition; they flip bases out of the DNA helix into a selective active site pocket, the architecture of which permits a sensitive detection of even minor base irregularities. Within the past few years, it has become clear that nature has exploited this ability to read the chemical structure of DNA bases for purposes other than canonical DNA repair. DNA glycosylases have been brought into context with molecular processes relating to innate and adaptive immunity as well as to the control of DNA methylation and epigenetic stability. Here, we summarize the key structural and mechanistic features of DNA glycosylases with a special focus on the mammalian enzymes, and then review the evidence for the newly emerging biological functions beyond the protection of genome integrity.
CD4+ Valpha14 NKT cells play a crucial role in an early stage of protective immunity against infection with Leishmania major (2000)

The roles of gamma delta T, NK and NKT cells in an early stage of protective immunity against infection with Leishmania major were investigated. Further, the contribution of these innate cells to the expression of 65 kDa heat shock protein (HSP65) in host macrophages was examined, since we found previously that this expression prevents apoptotic death of infected macrophages and is a crucial step in the acquisition of protective immunity against infection with various obligate intracellular protozoa including L. major. C57BL/6 and DBA/2 mice were found to be resistant against the infection on the basis of the parasite burden in their regional lymph nodes, and to strongly express HSP65 in their macrophages, whereas BALB/c mice were susceptible and barely expressed the HSP65. In those resistant mice, CD4(+) NKT cells prominently increased in their regional lymph node and were the main effector cells at least for an early stage of the protective immunity and for the HSP65 expression, whereas this subset did not increase in susceptible BALB/c mice. Further, neither gamma delta T nor NK cells in resistant mice contributed to those protective immune responses. The NKT cell subset bore CD3, CD4, TCR alpha beta, IL-2R beta and NK1.1 but scarcely asialo-GM(1). Moreover, this effector subset was confirmed to be V(alpha)14 NKT cells by using J(alpha)281(-/-) mice.
Purification of RIP60 and RIP100, mammalian proteins with origin-specific DNA-binding and ATP-dependent DNA helicase activities. (1990)

Replication of the Chinese hamster dihydrofolate reductase gene (dhfr) initiates near a fragment of stably bent DNA that binds multiple cellular factors. Investigation of protein interactions with the dhfr bent DNA sequences revealed a novel nuclear protein that also binds to domain B of the yeast origin of replication, the autonomously replicating sequence ARS1. The origin-specific DNA-binding activity was purified 9,000-fold from HeLa cell nuclear extract in five chromatographic steps. Protein-DNA cross-linking experiments showed that a 60-kDa polypeptide, which we call RIP60, contained the origin-specific DNA-binding activity. Oligonucleotide displacement assays showed that highly purified fractions of RIP60 also contained an ATP-dependent DNA helicase activity. Covalent radiolabeling with ATP indicated that the DNA helicase activity resided in a 100-kDa polypeptide, RIP100. The cofractionation of an ATP-dependent DNA helicase with an origin-specific DNA-binding activity suggests that RIP60 and RIP100 may be involved in initiation of chromosomal DNA synthesis in mammalian cells.
Species specificity of renin kinetics in transgenic rats harboring the human renin and angiotensinogen genes. (1992)

The renin-angiotensin system (RAS) is the most important regulatory system of electrolyte homeostasis and blood pressure. We report here the development of transgenic rats carrying the human angiotensinogen TGR-(hAOGEN) and human renin TGR(hREN) genes. The plasma levels and tissue distribution of the transcription and translation products from both genes are described. A unique species specificity of the enzyme kinetics was observed. The human RAS components in the transgenic rats did not interact with the endogenous rat RAS in vivo. Instead, infusions of exogenous human RAS components specifically interacted with human transgene translation products. Thus, infusion of human renin in TGR(hAOGEN) led to an increase of angiotensin II and an elevation of blood pressure, which could not be antagonized by the human-specific renin enzyme inhibitor Ro 42-5892. Rat renin also elevated blood pressure and angiotensin II in TGR(hAOGEN); however, this effect was not antagonized by the human renin inhibitor. Compared to mice, rats offer the advantage of chronic instrumentation and repetitive, sophisticated, hemodynamic, and endocrinological investigations. Thus, transgenic rat models with human-specific enzyme kinetics permit primate-specific analyses in non-primate in vivo and in vitro experimental systems.
A Reactive Location Service for Mobile Ad Hoc Networks (2002)

We present and analyze a reactive location service (RLS) for mobile ad hoc networks. RLS provides a mobile node in a wireless ad-hoc network with the means to inquire the current geographical position of another node on-demand and can be used as a building block for location-based routing. We provide a comparison of RLS to an ideal omniscient location service as well as to the complex Grid Location Service (GLS). In addition, we compare the performance of greedy location-based routing in combination with RLS to the performance of a non-location-based ad hoc routing approach, namely Dynamic Source Routing (DSR). DSR was chosen for the comparison since RLS can be considered an adaptation of DSR&amp;apos;s route discovery mechanisms to the location-based domain. We also introduce and study possible optimizations for RLS, in particular caching, random re-broadcast jitter, and re-broadcast suppression. The quantitative results of our NS-2 simulation study show a very good performance of RLS combined with greedy routing, outperforming GLS and DSR for scenarios with high mobility and high node density.
Loss of transforming growth factor beta 1 receptors and its effects on the growth of EBV-transformed human B cells (1991)

Transforming growth factor-beta (TGF-beta) is a potent negative regulator of normal human B cell growth mediated by exogenous signals, including IL-2 and low m.w. B cell growth factor 12 kDa (BCGF-12 kDa). In the present study, we investigated the regulatory linkage between viral or nonviral transformation of human B cells and the growth inhibitory effects of TGF-beta 1. A panel of EBV+ and EBV- B cell lines, derived either by in vitro EBV B cell transformation, or from cases of lymphoma was used to quantitate the negative growth effects of TGF-beta 1. The proliferative response of three EBV- B cell lines to rBCGF-12 kDa or serum was inhibited by low concentrations of TGF-beta 1 (0.2-0.5 ng/ml for 50% maximal effect), as measured by tritiated thymidine uptake and viable cellular recovery. In contrast, rBCGF-12 kDa or serum mediated proliferation of three EBV+ B cell lines was refractory to the growth inhibitory effects of TGF-beta 1. In an attempt to understand the mechanism(s) for this differential growth control in EBV+ and EBV- B cells, we studied the expression of TGF-beta 1, c-myc, and TGF-beta 1 receptors. No correlation was observed between the expression of TGF-beta 1 or c-myc gene and growth inhibition by TGF-beta 1 in the cell lines studied. Our results indicate that sensitivity or resistance to TGF-beta 1 correlated with the presence or absence (loss) of high affinity receptors for TGF-beta 1. EBV- B cell lines expressed levels of high affinity receptors similar to those found on activated normal B or T cells. In contrast, EBV+ B cell lines showed no detectable high affinity receptors. Chemical cross-linking studies with a bifunctional reagent, dissuccinimidyl suberate revealed a normal expression of type I (65-70 kDa), type II (85-90 kDa), and type III (280-300 kDa) TGF-beta 1 high affinity receptors on EBV- B cell lines. In contrast, EBV+ B cell lines did not express type I and type II receptors, whereas type III receptors were expressed but could not be inhibited by unlabeled TGF-beta 1.(ABSTRACT TRUNCATED AT 400 WORDS)
Total synthesis of (.+-.)-.DELTA.9-tetrahydrocannabinol and four of its isomers (1967)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTotal synthesis of (.+-.)-.DELTA.9-tetrahydrocannabinol and four of its isomersKenneth E. Fahrenholtz, M. Lurie, and Richard W. KiersteadCite this: J. Am. Chem. Soc. 1967, 89, 23, 5934–5941Publication Date (Print):November 1, 1967Publication History Published online1 May 2002Published inissue 1 November 1967https://pubs.acs.org/doi/10.1021/ja00999a034https://doi.org/10.1021/ja00999a034research-articleACS PublicationsRequest reuse permissionsArticle Views1761Altmetric-Citations75LEARN 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
The use of glucagon in hydrostatic reduction of intussusception: a double-blind study of 30 patients. (1983)

Thirty patients were referred for hydrostatic reduction of ileocolic intussusception. Children with suspected gangrenous bowel or sensitivity to glucagon were excluded from the investigation. A standard protocol for the procedure was used in all patients, including the intravenous administration of glucagon or placebo (0.05 mg/kg) when the intussusception was encountered. Successful reduction was achieved in 53% of both control and glucagon-treated patients. Analysis of the length of the procedure and the ease of reduction of the intussusception indicated no difference in the two groups. This multicenter double-blind study failed to show any therapeutic value of glucagon in hydrostatic reduction of intussusception.
The Spatial and Temporal Expression of Potato ci21A Promoter in Tomato and Arabidopsis (2009)

The Asr gene is related to a number of functions, such as sugar regulation, stress induction, and fruit ripening in many plants, including tomato, potato, grape, pine, and rice. We used the promoter of the ci21A gene of potato, which belongs to the Asr family, to characterize the genetic expression of this gene in tomato and Arabidopsis. Particularly, there is known to be no Asr gene in Arabidopsis. In order to identify the spatial and temporal expression of the ci21A promoter, we used β-glucuronidase (GUS) as the reporter gene. The ci21A-GUS fusion gene was found to exhibit a very similar expression pattern in transgenic tomato and Arabidopsis. The distribution of GUS revealed that most of the expression appears in the sink organs of tomato and Arabidopsis. The expression pattern controlled by ci21A promoter helped us to clarify the role of the ASR protein in the developmental processes of plants. It also provided the possibility of applying this promoter in the expression of foreign genes in plants. The ci21A promoter could be suitable for various applications in different species.
Preparation and Utilization of a Biosensor Based on Galactose Oxidase (1992)

An enzyme electrode for D-galactose determination was prepared by fixation of a carrier with immobilized galactose oxidase (E.C. 1.1.3.9) or coimmobilized galactose oxidase and catalase (E.C. 1.11.1.6) to a Clark-type oxygen sensor. The enzymes were immobilized either on a partially hydrolyzed nylon mesh or on a native collagen membrane using the Ugi reaction with cyclohexyl isocyanide and glutaraldehyde. The biosensors were characterized by the specific activity of the immobilized galactose oxidase, the apparent Michaelis constant K M(app.) , and the stability expressed by time and a number of the performed analyses. The substrate specificity of the biosensor and the effect of pH and temperature of the reaction mixture on the response magnitude were also tested. The prepared biosensor was used for the determination of D-galactose content in samples of blood plasma and serum of patients with suspected galactosemia.
Nucleic acids of mammalian origin can act as endogenous ligands for Toll-like receptors and may promote systemic lupus erythematosus (2005)

Raised serum levels of interferon (IFN)-alpha have been observed in systemic lupus erythematosus (SLE) patients, and these levels are correlated with both disease activity and severity. The origin of this IFN-alpha is still unclear, but increasing evidence suggests the critical involvement of activated plasmacytoid predendritic cells (PDCs). In SLE patients, DNA and RNA viruses, as well as immune complexes (ICs), that consist of autoantibodies specific to self-DNA and RNA protein particles can stimulate production of IFN-alpha. We have developed three series of oligonucleotide (ODN)-based inhibitors of Toll-like receptor (TLR) signaling. These ODNs include inhibitors of TLR9, inhibitors of TLR7 but not TLR9, and sequences that inhibit both TLR7 and TLR9. Specificity of these inhibitors is confirmed by inhibition of IFN-alpha production by PDCs in response to DNA or RNA viruses. We show that mammalian DNA and RNA, in the form of ICs, are potent self-antigens for TLR9 and TLR7, respectively, and induce IFN-alpha production by PDCs. This work suggests that TLRs may have a critical role in the promotion of lupus through the induction of IFN-alpha by PDCs. These inhibitors of TLR signaling thus represent novel therapeutic agents with potential for the treatment of lupus.
Laser‐facilitated epicutaneous immunotherapy with hypoallergenic beta‐glucan neoglycoconjugates suppresses lung inflammation and avoids local side effects in a mouse model of allergic asthma (2020)

Conjugation of ovalbumin to laminarin increased its immunogenicity while at the same time reducing local side effects. LamOVA EPIT via laser-generated micropores is safe and equally effective compared to SCIT with alum, without the need for adjuvant.
Predicted alpha-helical regions of the prion protein when synthesized as peptides form amyloid. (1992)

By comparing the amino acid sequences of 11 mammalian and 1 avian prion proteins (PrP), structural analyses predicted four alpha-helical regions. Peptides corresponding to these regions of Syrian hamster PrP were synthesized, and, contrary to predictions, three of the four spontaneously formed amyloids as shown by electron microscopy and Congo red staining. By IR spectroscopy, these amyloid peptides exhibited secondary structures composed largely of beta-sheets. The first of the predicted helices is the 14-amino acid peptide corresponding to residues 109-122; this peptide and the overlapping 15-residue sequence 113-127 both form amyloid. The most highly amyloidogenic peptide is AGAAAAGA, which corresponds to Syrian hamster PrP residues 113-120 and is conserved across all species for which the PrP sequence has been determined. Two other predicted alpha-helices corresponding to residues 178-191 and 202-218 form amyloids and exhibit considerable beta-sheet structure when synthesized as peptides. These findings suggest the possibility that the conversion of the cellular isoform of PrP to the scrapie isoform of PrP involves the transition of one or more putative PrP alpha-helices into beta-sheets and that prion diseases are disorders of protein conformation.