gebhart/patrepeval huggingface dataset:
Preparation of stable 1,4-dihydropyrazines (1987)

The N-phenacylarylamine (4) gives the N,N-diphenacyl derivative (5) on treatment with phenacyl bromide under phase-transfer catalysis conditions. Condensation of (5) with an arylamine results in the formation of the thermally stable 1,4-diaryl-3,5-diphenyl-1,4-dihydropyrazine (6) in moderate yield. 1,2-Diaryl-3,6-diphenyl-1,2-dihydropyrazine (9) is obtained by heating N-phenacylarylamine (4). Formation of (9) is also promoted by a Lewis acid at lower temperature.
Peripheral and Central Mechanisms of NGF‐induced Hyperalgesia (1994)

Mechanisms underlying the hyperalgesia induced by a single systemic injection of nerve growth factor (NGF) in adult rats were studied in vivo. A single dose of NGF initiated a prolonged thermal hyperalgesia to a radiant heat source within minutes that lasted for days. Animals which had been pretreated with the mast cell degranulating compound 48/80 or either one of two specific 5-hydroxytryptamine receptor antagonists (ICS 205-930 and methiothepin) also developed an NGF-induced thermal hyperalgesia, but onset was delayed by more than 3 h. In the presence of ICS 205-930 or methiothepin the early component NGF-induced hyperalgesia was reversed and the animals responded with an initial hypoalgesia to the thermal stimuli. Whereas these results indicate a peripheral mechanism for the initial thermal hyperalgesia, the later phase (7 h-4 days after NGF) appeared to be centrally maintained, since it could be selectively blocked by the non-competitive NMDA receptor antagonist MK-801. In contrast to the almost immediate thermal hyperalgesia following a single injection of NGF, a significant mechanical hyperalgesia began only after a 7 h latency. This NGF-induced mechanical hyperalgesia was not blocked by any of the treatments that attenuated the thermal hyperalgesia, indicating that a separate mechanism may be involved. Additional electrophysiological experiments showed that NGF-induced hyperalgesia was not maintained by an increased amount of spontaneous activity in C-fibres. A final result showed that endogenous release of NGF in a model of acute inflammation (complete Freund's adjuvant-induced inflammation) may be involved in the development of thermal hyperalgesia, since it could be blocked by concomitant treatment with anti-NGF antisera. These data indicate that NGF-induced thermal and mechanical hyperalgesia are mediated by different mechanisms. The rapid onset component of thermal hyperalgesia is due to a peripheral mechanism involving the degranulation of mast cells, whereas the late component involves central NMDA receptors. In contrast, the NGF-induced mechanical hyperalgesia seems to be independent of mast cell degranulation or central NMDA receptor sites.
Autonomous Collision-Free Navigation of Microvehicles in Complex and Dynamically Changing Environments (2017)

Self-propelled micro- and nanoscale robots represent a rapidly emerging and fascinating robotics research area. However, designing autonomous and adaptive control systems for operating micro/nanorobotics in complex and dynamically changing environments, which is a highly demanding feature, is still an unmet challenge. Here we describe a smart microvehicle for precise autonomous navigation in complicated environments and traffic scenarios. The fully autonomous navigation system of the smart microvehicle is composed of a microscope-coupled CCD camera, an artificial intelligence planner, and a magnetic field generator. The microscope-coupled CCD camera provides real-time localization of the chemically powered Janus microsphere vehicle and environmental detection for path planning to generate optimal collision-free routes, while the moving direction of the microrobot toward a reference position is determined by the external electromagnetic torque. Real-time object detection offers adaptive path planning in response to dynamically changing environments. We demonstrate that the autonomous navigation system can guide the vehicle movement in complex patterns, in the presence of dynamically changing obstacles, and in complex biological environments. Such a navigation system for micro/nanoscale vehicles, relying on vision-based close-loop control and path planning, is highly promising for their autonomous operation in complex dynamic settings and unpredictable scenarios expected in a variety of realistic nanoscale scenarios.
Simultaneous measurement of temperature and strain using a step spectrum profile fibre Bragg grating arrangement (2004)

A sensing head for simultaneous measurement of temperature and strain is presented and analyzed. The proposed configuration is based on the combination of two Bragg gratings, written in different fibers and with different reflectivities, to form a single signature with a reflected step spectrum profile. By measuring the changes in the peak wavelength and spectral width of this signature, resolutions of 0.65&deg;C/&radic;Hz and &plusmn;2.55 &mu;&epsilon;/&radic;Hz were achieved for temperature and strain measurements, respectively.
Phase equilibria in block copolymer-homopolymer mixtures (1993)

Phase equilibria in block copolymer (AB) + homopolymer (A) blends are considered theoretically in the strong segregation limit. The effect of homopolymer molecular weight is analyzed. In particular, the following are shown: (i) Long enough A-homopolymer chains (N(h) much greater than N(hc)) are incompatible with stretched A-blocks so that homopolymer and block copolymer should be space separated in any morphology. (ii) Interaction between copolymer micelles in the region N(h) much greater than N(hc) crucially depends on homopolymer molecular weight. For N(h) &lt;N(h)* interaction of copolymer micelles of any geometry is purely repulsive (here N(h)* much greater than N(hc)). On the other hand, micelles strongly attract each other (at not too short distances) if N(h) &gt; N(h)*. Separation of the system into two phases (block copolymer and homopolymer) is predicted as a result of this attraction. (iii) Addition of A-homopolymer to an AB-copolymer system with minor A-blocks results in a shifting of the regions of stability of the cylindrical and spherical morphologies toward more symmetric copolymers(smaller fraction of major B-blocks). In particular, the spherical morphology with matrix B-blocks could be the most favorable even if the volume fraction of the B-component is nearly 50%.
Altered cobalamin metabolism in Escherichia coli btuR mutants affects btuB gene regulation (1989)

Synthesis of the Escherichia coli outer membrane protein BtuB, which mediates the binding and transport of vitamin B12, is repressed when cells are grown in the presence of vitamin B12. Expression of btuB-lacZ fusions was also found to be repressed, and selection for constitutive production of beta-galactosidase in the presence of vitamin B12 yielded mutations at btuR. The btuR locus, at 27.9 min on the chromosome map, was isolated on a 952-base-pair EcoRV fragment, and its nucleotide sequence was determined. The BtuR protein was identified in maxicells as a 22,000-dalton polypeptide, as predicted from the nucleotide sequence. Strains mutant at btuR had negligible pools of adenosylcobalamin but did convert vitamin B12 into other derivatives. Although btuB expression in a btuR strain could not be repressed by cyano- or methylcobalamin, it was repressed by adenosylcobalamin. Growth on ethanolamine as the sole nitrogen source requires adenosylcobalamin. btuR mutants grew on ethanolamine but were affected in the length of the lag period before initiation of growth, which suggested that an alternative route for adenosylcobalamin synthesis might exist. No mutations were found that conferred constitutive btuB expression in the presence of adenosylcobalamin. Other genes near btuR may also be involved in cobalamin metabolism, as suggested from the complementation behavior of strains generated by excision of the Tn10 element in btuR. These results indicated that the btuR product is involved in the metabolism of adenosylcobalamin and that this cofactor, or some derivative, controls btuB expression.
Synthesis of homo- and hetero-bimetallic complexes incorporating the [(η5-C5H4)CMe2(η5-C9H6)] ligand (1994)

The new bimetallic complexes[(η5-C5H5)MCl2{(η5-C5H4)CMe2(η5-C9H6)}M*Cl2(η5-C5H5)](M = Zr, M*= Zr, Hf; M = Hf, M*= Zr, Hf), [(η5-C5H5)ZrCl2]{[(η5-C5H4)CM2(η5-C9H6)}ZrCl2(η5-C5Me5)], [(η5-C5H5)ZrCl2{(η5-C5H4)Cme2(η5-C9H6)}Rh(CO)2] and [(η5-C5H5)ZrCl2]{[(η5-C5H4)CMe2(η5-C9H6)}Mn(CO)3] have been prepared from the precursors [{Me2C(η5-C5H4)(η2-C9H6)}M(η5-C5H5)Cl](M = Zr 1, Hf 2); the X-ray crystal structure of 1 is reported.
A Neuron-Based Screening Platform for Optimizing Genetically-Encoded Calcium Indicators (2013)

Fluorescent protein-based sensors for detecting neuronal activity have been developed largely based on non-neuronal screening systems. However, the dynamics of neuronal state variables (e.g., voltage, calcium, etc.) are typically very rapid compared to those of non-excitable cells. We developed an electrical stimulation and fluorescence imaging platform based on dissociated rat primary neuronal cultures. We describe its use in testing genetically-encoded calcium indicators (GECIs). Efficient neuronal GECI expression was achieved using lentiviruses containing a neuronal-selective gene promoter. Action potentials (APs) and thus neuronal calcium levels were quantitatively controlled by electrical field stimulation, and fluorescence images were recorded. Images were segmented to extract fluorescence signals corresponding to individual GECI-expressing neurons, which improved sensitivity over full-field measurements. We demonstrate the superiority of screening GECIs in neurons compared with solution measurements. Neuronal screening was useful for efficient identification of variants with both improved response kinetics and high signal amplitudes. This platform can be used to screen many types of sensors with cellular resolution under realistic conditions where neuronal state variables are in relevant ranges with respect to timing and amplitude.
Small interfering RNA (siRNA) inhibits the expression of the Her2/neu gene, upregulates HLA class I and induces apoptosis of Her2/neu positive tumor cell lines (2003)

Silencing of a specific mRNA using double stranded RNA oligonucleotides represents one of the newest technologies for suppressing a specific gene product. Small interfering RNA (siRNA) are 21 nucleotides long, double stranded RNA fragments that are identical in sequence to the target mRNA. We designed 3 such siRNA against the Her2/neu (HER2) gene. The HER2 gene is known to play an important role in the oncogenesis of several types of cancers, such as breast, ovarian, colon and gastric cancers. Introduction of the siRNA into HER2 positive tumor lines in vitro greatly reduced the cell surface expression of the HER2 protein. Concurrently, a range of effects on cell physiology, such as growth inhibition or apoptosis, was observed. The expression of HLA class I was observed to be upregulated when HER2 was silenced with siRNA. Treatment of SKBr3 and MCF7/HER2 tumor cell lines with the HER2 siRNA resulted in growth arrest of cells in the late G(1)/S-phase. Our results suggest that siRNA may be an effective method of abrogating the effect of HER2 in tumorigenesis.
Novel tretinoin formulations: a drug-in-cyclodextrin-in-liposome approach (2013)

According to our results, Tretinoin-UDV with 20% lipid concentration seems to be a better approach than Tretinoin-CyD-UDV, attending to the higher chemical stability.
Potential Utility of Uroplakin III, Thrombomodulin, High Molecular Weight Cytokeratin, and Cytokeratin 20 in Noninvasive, Invasive, and Metastatic Urothelial (Transitional Cell) Carcinomas (2003)

The morphology of urothelial carcinomas, particularly when poorly differentiated or in metastatic sites, is not distinctive and overlaps significantly with other poorly differentiated nonurothelial carcinomas. Currently, there is no widely used single marker or panel of markers to confirm urothelial origin. We evaluated a panel consisting of antibodies to uroplakin III (UROIII), thrombomodulin (THR), high molecular weight cytokeratin (HMWCK), and cytokeratin 20 (CK20) in a wide range of urothelial tumors. Immunohistochemistry was performed on 112 paraffin-embedded urothelial neoplasms: 14 low malignant potential, 16 low-grade noninvasive, 16 high-grade noninvasive, 36 invasive, and 25 metastatic and 5 small cell carcinomas of the urinary bladder. Tissue microarray analysis was used to examine 498 tissue cores of nonurothelial tumors and normal tissue using antibodies to UROIII, THR, and HMWCK. Overall positive staining results in all urothelial tumors are as follows: UROIII, 64 of 112 (57.1%); THR, 77 of 112 (68.8%); HMWCK, 88 of 110 (80%); and CK20, 53 of 110 (48.2%). The expression of the four markers varied with tumor grade and stage. All small cell carcinomas were negative for all markers. Variant morphologic subtypes showed similar staining as conventional urothelial carcinomas. Tissue microarray analysis showed no UROIII immunoreactivity in tissue cores of nonurothelial tumors. THR was expressed by a limited number of nonurothelial cores (10 of 37 [27%] non-small cell lung carcinomas, 2 of 36 [5.6%] lymphomas). HMWCK was expressed by 43.8% of non-small cell lung carcinomas and essentially absent in other nonurothelial tumor cores. Based on the results of the study, the expression of UROIII in a tumor is essentially diagnostic of urothelial origin; however, it is expressed in only slightly more than half of urothelial tumors. The coexpression of THR, HMWCK, and CK20 strongly suggests urothelial origin. The coexpression of two of three non-UROIII markers (THR, HMWCK, CK20) suggests urothelial origin but requires clinicopathologic correlation. The results of the study indicate a role for an antibody panel that includes UROIII, THR, HMWCK, and CK20 in the diagnosis of urothelial tumors.
An electrode-supported oxidation catalyst based on ruthenium(IV). pH "encapsulation" in a polymer film (1981)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAn electrode-supported oxidation catalyst based on ruthenium(IV). pH "encapsulation" in a polymer filmGeorge J. Samuels and Thomas J. MeyerCite this: J. Am. Chem. Soc. 1981, 103, 2, 307–312Publication Date (Print):January 1, 1981Publication History Published online1 May 2002Published inissue 1 January 1981https://doi.org/10.1021/ja00392a010Request reuse permissionsArticle Views345Altmetric-Citations71LEARN 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 InReddit PDF (712 KB) Get e-Alertsclose Get e-Alerts
Synthesis, Structure, and Electrochemical Characterization of Nanocrystalline Tantalum and Tungsten Nitrides (2007)

Nanocrystalline tantalum and tungsten nitrides were synthesized by a two‐step ammonolysis reaction of transition metal chlorides. The first step involves ammonolysis of tantalum and tungsten chlorides at room temperature using anhydrous chloroform as the solvent. A second step consists of heat treatment of these as‐prepared powders under anhydrous NH 3 atmosphere leading to the formation of tantalum and tungsten nitride nanocrystallites at relatively low temperature (600°–675°C). The ammonolysis, nitridation, structure, morphology, surface area, density, and electronic conductivity of the nitrides obtained were studied and characterized. The electrochemical responses of these nitrides were also measured by cyclic voltammetry using 1 M KOH electrolyte.
The Cytokine Response Profile of Ebola Virus Disease in a Large Cohort of Rhesus Macaques Treated With Monoclonal Antibodies (2019)

Ebola virus (EBOV) is a highly pathogenic filovirus that causes outbreaks of a severe hemorrhagic fever known as EBOV disease (EVD). Ebola virus disease is characterized in part by a dysregulated immune response and massive production of both pro- and anti-inflammatory cytokines. To better understand the immune response elicited by EVD in the context of treatment with experimental anti-EBOV antibody cocktails, we analyzed 29 cytokines in 42 EBOV-infected rhesus macaques. In comparison to the surviving treated animals, which exhibited minimal aberrations in only a few cytokine levels, nonsurviving animals exhibited a dramatically upregulated inflammatory response that was delayed by antibody treatment.
Outer Membrane Vesicles of Porphyromonas gingivalis Elicit a Mucosal Immune Response (2011)

We previously reported that mutation of galE in Porphyromonas gingivalis has pleiotropic effects, including a truncated lipopolysaccharide (LPS) O-antigen and deglycosylation of the outer membrane protein OMP85 homolog. In the present study, further analysis of the galE mutant revealed that it produced little or no outer membrane vesicles (OMVs). Using three mouse antisera raised against whole cells of the P. gingivalis wild type strain, we performed ELISAs to examine the reactivity of these antisera with whole cells of the wild type or the galE mutant. All three antisera had significantly lower reactivity against the galE mutant compared to wild type. OMVs, but not LPS, retained the immunodominant determinant of P. gingivalis, as determined by ELISAs (with wild type LPS or OMVs as antigen) and absorption assays. In addition, we assessed the capacity of OMVs as a vaccine antigen by intranasal immunization to BALB/c mice. Synthetic double-stranded RNA polyriboinosinic polyribocytidylic acid [Poly (I∶C)], an agonist of Toll-like receptor 3 (TLR3), was used as the mucosal adjuvant. Vaccination with OMV elicited dramatically high levels of P. gingivalis-specific IgA in nasal washes and saliva, as well as serum IgG and IgA. In conclusion, the OMVs of P. gingivalis have an important role in mucosal immunogenicity as well as in antigenicity. We propose that P. gingivalis OMV is an intriguing immunogen for development of a periodontal disease vaccine.
Dissection of a quantitative trait locus for genetic hypertension on rat chromosome 10. (1995)

We have previously identified a locus on rat chromosome 10 as carrying a major hypertension gene, BP/SP-1. The 100:1 odds support interval for this gene extended over a 35-centimorgan (cM) region of the chromosome that included the angiotensin I-converting enzyme (ACE) locus as demonstrated in a cross between the stroke-prone spontaneously hypertensive rat (SHRSPHD) and the normotensive Wistar-Kyoto (WKY-0HD) rat. Here we report on the further characterization of BP/SP-1, using a congenic strain, WKY-1HD. WKY-1HD animals carry a 6-cM chromosomal fragment genotypically identical with SHRSPHD on chromosome 10, 26 cM away from the ACE locus. Higher blood pressures in the WKY-1HD strain compared with the WKY-0HD strain, as well as absence of linkage of the chromosome 10 region to blood pressure in an F2 (WKY-1HD x SHRSPHD) population suggested the existence of a quantitative trait locus, termed BP/SP-1a, that lies within the SHRSP-congenic region in WKY-1HD. Linkage analysis in the F2 (WKY-0HD x SHRSPHD) cross revealed that BP/SP-1a is linked to basal blood pressure, whereas a second locus on chromosome 10, termed BP/SP-1b, that maps closer to the ACE locus cosegregates predominantly with blood pressure after exposure to excess dietary NaCl. Thus, we hypothesize that the previously reported effect of BP/SP-1 represents a composite phenotype that can be dissected into at least two specific components on the basis of linkage data and congenic experimentation. One of the loci identified, BP/SP-1a, represents the most precisely mapped locus affecting blood pressure that has so far been characterized by random-marker genome screening.
A Series of Cerebral Venous Sinus Thromboses Treated with Intra-Arterial tPA infused over Ten Hours with a 0.027-inch Catheter and Literature Review (2016)

Cerebral venous sinus thrombosis (CVST) can have devastating results, with mortality reported in 44% of cases. No randomized trials exist in order to define what qualifies as failure of conservative therapy, and there is no specific intervention to date which is considered safe and effective. Case series suggest that thrombolysis infusion is safer than thrombectomy, but methods of administration, dose, and duration of therapy tend to vary widely. We present three consecutive CVST patients treated with heparin who suffered both clinical and radiographic deterioration, and went on to have endovascular therapy. Each patient was successfully recanalized by placing a 0.027-inch microcatheter at the proximal portion of the thrombus and infusing 20 mg of alteplase dissolved in 1 liter of normal saline infused at 100 ml per hour for an infusion of 2 mg of alteplase per hour for ten hours.
Antigenic and immunogenic epitopes shared by human papillomavirus type 16 and bovine, canine, and avian papillomaviruses (1991)

All types of papillomaviruses (PV) share common, so-called group-specific epitopes. To identify the major group-specific epitopes, we immunized 26 guinea pigs or rabbits with purified bovine PV type 1 (BPV), canine PV, or avian PV from the common chaffinch. The resulting hyperimmune sera, as well as a commercially available rabbit antiserum to BPV and seven monoclonal antibodies to BPV, were tested in an enzyme-linked immunosorbent assay with a set of 66 overlapping 20-amino-acid peptides representing the complete sequence of the major capsid proteins (L1 and L2) of human PV type 16 (HPV 16). Sera from the same animals before immunization were used as controls. The minimal reactive epitopes within each peptide were further characterized by testing of truncated peptides. The cross-reactive epitopes were clustered in two regions of L1, an internal region (at positions 171 to 235), which contained three epitopes, and the more reactive region at the carboxy terminus (at positions 411 to 475), which contained six epitopes. The most reactive of the HPV 16 broadly cross-reactive epitopes was a carboxy-terminal epitope which had the sequence DTYRF and which reacted with nine of the antisera to BPV, canine PV, or avian PV, with the commercially available rabbit antiserum to BPV, and also with a mouse monoclonal antibody to BPV. Antipeptide antisera to all of the HPV 16 L1 peptides and to the most antigenically reactive of their truncated analogs were made in guinea pigs. Antipeptide antisera reactive with BPV were obtained for three of the cross-reactive epitopes, and one of these antisera allowed highly sensitive detection of group-specific PV antigen by immunoperoxidase staining.