gebhart/patrepeval huggingface dataset:
The outer membrane of Pasteurella multocida 3:A protects rabbits against homologous challenge (1991)

The protective efficacy of a vaccine purified from the Pasteurella multocida 3:A outer membrane (OM) was evaluated in rabbits by homologous challenge. Twenty-seven rabbits were divided into four groups: 1, vaccinated with OM and challenged; 2, nonvaccinated and challenged; 3, vaccinated with OM only; and 4, nonvaccinated and not challenged. Rabbits were immunized intranasally with 1 mg of OM protein on days 0, 7, 14, and 35, challenged intranasally on day 49, and killed on day 63. Mortality rates were 0, 67, 0, and 0% for groups 1 through 4, respectively. The prevalence of pneumonia was reduced from 73 (group 2) to 20% (group 1). The severity of pneumonia was reduced from 0.62 (group 2) to 0.07 (group 1), as measured by the group lesion index. The number of P. multocida in nasal cavities was reduced from 3.89 x 10(5) (group 2) to 6.19 x 10(2) (group 1). The geometric mean number of P. multocida in lungs was 8,360,000-fold less in group 1 than in group 2. Similarly, the prevalence of P. multocida colonization in nonrespiratory organs was reduced from 47 (group 2) to 4% (group 1). Furthermore, group 1 and 3 rabbits developed significantly elevated immunoglobulin A antibodies in nasal secretions and lung lavages and significantly elevated immunoglobulin G antibodies in lung lavages and sera. In addition, rabbit immune sera contained antibodies against P. multocida OM proteins and lipopolysaccharides and inhibited P. multocida proliferation in mouse lungs. These results indicate that a vaccine prepared from the OM of P. multocida provides a significant protection in rabbits against homologous challenge.
Effects of Applied Electric Fields on Low-Calcium Epileptiform Activity in the CA1 Region of Rat Hippocampal Slices (2000)

It is well established that exogenous electric fields can suppress activity obtained in different models of epileptiform discharge such as penicillin and high potassium. In the low-calcium model of epilepsy, spontaneous epileptiform bursting is generated in the absence of synaptic transmission. It has been suggested that ephaptic interactions play a critical role in neuronal synchronization and burst propagation in this nonsynaptic model. We, therefore, tested the hypothesis that low-calcium bursting induced in the CA1 region of transverse and longitudinal hippocampal slices should be highly sensitive to exogenous electric fields. Uniform, low amplitude DC electric fields were applied during spontaneous low-calcium epileptiform activity. Modulation and full suppression of epileptiform activity was observed at field strengths between 1 and 5 mV/mm, a value significantly lower than in other in vitro models of epilepsy. We further investigated the hypothesis that the efficacy of electrical fields was related to changes in the extracellular space. Our results suggest that the osmolality of the perfusate can modulate the efficacy of electric fields. It was also observed that the ability of a field to suppress or modulate low-calcium activity was highly dependent on its orientation, polarity, as well as magnitude. Finally, it was observed that the extracellular potassium "waves" that normally accompany individual epileptiform events was abolished when the individual events were suppressed. These results suggest that DC fields modulate and suppress low-calcium activity by directly polarizing CA1 pyramidal cells.
Long-term colloidal stability of polymer-grafted silica nanoparticles in concentrated brine at elevated temperatures (2017)

Random copolymer poly(AA-co-AMPS) chains were grafted covalently onto amine coated individual ~20 nm silica nanoparticles (NPs) without forming aggregates. The hydrodynamic diameter of the grafted silica NPs remained constant at ~25 nm for over six weeks up to 90°C in 100% API brine indicating electrosteric stabilization. The grafting efficiency was enhanced by catalysis with EDC and N-hydroxysuccinimide to increase the half-life of the intermediates on the AA groups to form negatively charged intermediates on the AA groups to attract the protonated amines on the NPs. The higher reaction rate for the activated AA groups, relative to the collision rate of the NPs favored multiple grafting of a bound polymer to the same nanoparticle versus bridging of the polymer chain to a second nanoparticle. After extreme dilution, the particles were still stable in brine indicating the chains were permanently grafted. The random copolymer poly(AA-co-AMPS) was found to be able to stay swelled and elongated in a wide range of pH (pH 4 to 12) and provide colloidal stability for the silica NPs due to the high solvation of the AMPS groups.
Immunological detection of Chinese hamster ovary cells expressing a multidrug resistance phenotype. (1985)

A monoclonal antibody (IgG1) has been prepared that specifically detects Chinese hamster ovary cells expressing a multidrug-resistant phenotype. This antibody recognizes the membrane P-glycoprotein (Mr 170,000) associated with drug resistance as determined by enzyme-linked immunosorbent assay with purified P-glycoprotein and by Western blot analysis of cell extracts from drug-resistant and drug-sensitive cells. By immunofluorescence methods, the antibody also reacts strongly with viable and ether:ethanol-fixed resistant cells but does not react with the parent drug-sensitive cell line. Thus, this antibody can bind with live cells allowing discrimination by immunohistochemistry between drug-resistant and drug-sensitive Chinese hamster ovary cells.
Leflunomide: Efficacy and safety in clinical trials for thetreatment of rheumatoid arthritis (2000)

Leflunomide is a new disease modifying antirheumatic drug (DMARD) that inhibits lymphocyte proliferation by blocking dihydroorotate dehydrogenase (DHODH), the enzyme critical for the production of pyrimidine necessary for DNA synthesis. Through this mode of action, leflunomide inhibits the lymphocyte proliferation associated with the clonal expansion of T cells in rheumatoid arthritis (RA). In clinical trials, leflunomide was superior to placebo and comparable to sulfasalazine and methotrexate for improving both the signs and symptoms of RA. Leflunomide was also superior to placebo and sulfasalazine and comparable to methotrexate in overall improvement of physical function. Leflunomide was equivalent to methotrexate and sulfasalazine in retarding disease progression measured radiographically. Due to its unique mode of action in the treatment of RA, leflunomide shows value in combination therapy with methotrexate for patients refractory to methotrexate alone. The most common adverse reactions associated with leflunomide therapy include gastrointestinal symptoms, allergic reactions, reversible alopecia and elevated liver enzymes. Adverse events were generally mild to moderate, and resolved without complication. The results of phase II and phase III clinical trials indicate that leflunomide is a safe and efficacious drug for the treatment of RA.
Reversing the Inactivation of Peroxiredoxins Caused by Cysteine Sulfinic Acid Formation (2003)

The active-site cysteine of peroxiredoxins is selectively oxidized to cysteine sulfinic acid during catalysis, which leads to inactivation of peroxidase activity. This oxidation was thought to be irreversible. However, by metabolic labeling of mammalian cells with 35S, we show that the sulfinic form of peroxiredoxin I, produced during the exposure of cells to H2O2, is rapidly reduced to the catalytically active thiol form. The mammalian cells' ability to reduce protein sulfinic acid might serve as a mechanism to repair oxidatively damaged proteins or represent a new type of cyclic modification by which the function of various proteins is regulated.
Capacity of listeriolysin O, streptolysin O, and perfringolysin O to mediate growth of Bacillus subtilis within mammalian cells (1992)

The Listeria monocytogenes hemolysin listeriolysin O (LLO) plays a major role in mediating the escape of L. monocytogenes from a vacuolar compartment. In a previous report, it was shown that Bacillus subtilis expressing LLO could escape from a host vacuolar compartment and grow in the cytoplasm (J. Bielecki, P. Youngman, P. Connelly, and D. A. Portnoy, Nature [London] 345:175-176, 1990). In the present study, two related thiol-activated hemolysins, streptolysin O (SLO) and perfringolysin O (PFO), were expressed in B. subtilis and their ability to mediate intracellular growth was monitored by visual inspection and by assaying for CFU. Like LLO, PFO was active within the vacuolar environment, whereas SLO showed negligible activity. However, expression of PFO seemed to damage the host cells. The pH of the vacuole probably had little to do with these results, since all three hemolysins showed full or enhanced activity at pH 5.5, although LLO showed greatly reduced activity at pH 7. In addition, neutralization of the pH within host vacuoles by using weak bases had little effect on the lysis of the vacuole. The lack of SLO activity is probably caused by its lower specific activity; the purified protein had 10-fold less activity on a molar basis. These results suggest that LLO is not unique in its capacity to mediate intracellular growth of B. subtilis.
Methionine Dependency of Malignant Tumors: A Possible Approach for Therapy (1990)

When methionine (Met), an essential amino acid, was substituted for by its precursor homocysteine (Hcy) in the culture medium, normal cells such as fibroblasts proliferated normally. In contrast, many tumor cells failed to grow or grew at a lower rate. Met dependency is acquired simultaneously with cell transformation, as observed with HBL 100, a human mammary epithelial cell line that acquired increased malignancy as a function of in vitro passage number, and NIH/3T3 (J10), a mouse fibroblast line transformed by transfection with the human HRAS oncogene. A relationship was observed between Met dependency and metastatic potential of the RMS-21, RMS-S4T, and RMS-J1 sublines derived from RMS-0, a rat rhabdomyosarcoma cell line: the higher the metastatic potential of the cell line, the higher the concentration of Met required to maintain its proliferation. Met-independent cells derived from the RMS-0 line, obtained by a progressive decrease of Met in the culture medium lost their tumorigenicity when injected into rats fed with Met-deprived diets. In addition, the in vitro motility of RMS-S4T tumor cells, a marker of metastatic capability, decreased in Met-free Hcy-complemented (Met- Hcy+) medium. Similarly, RMS-0 tumor cells, preincubated in a Met- Hcy+ culture medium for 24 hours, evidenced a decreased capacity to form lung colonies when injected into syngeneic rats: the median number of lung colonies was 27 and 3 (P less than .05) for cells cultivated in Met+ Hcy- and Met- Hcy+ media, respectively. An amino acid-defined mixture reproducing casein composition was used as a protein source in the diets fed to RMS-J1 tumor-bearing rats. Dietary substitution of Hcy for Met (i.e., met deprivation) resulted in decreased tumor growth (from 44.4 +/- 1.0 to 40.6 +/- 1.4; P less than .05) and prevention of metastatic spread (from 37 to 0; P less than .05). In conclusion, exogenous Met can be substituted for Hcy to maintain the survival of normal cells but is essential for tumor cell growth in vivo as well as in vitro. Therefore, this defect of cancerous versus normal cells could be used for a therapeutic purpose.
3D nano- and micro-patterning of Biomaterials for Controlled Drug Delivery (2016)

Recently, there has been an emerging interest in controlling 3D structures and designing novel 3D shapes for drug carriers at nano- and micro-scales. Certain 3D shapes and structures of drug particles enable transportation of the drugs to desired areas of the body, allow drugs to target specific cells and tissues, and influence release kinetics. Advanced nano- and micro-manufacturing methods including 3D printing, photolithography-based processes, microfluidics and DNA origami have been developed to generate defined 3D shapes and structures for drug carriers. This paper reviews the importance of 3D structures and shapes on controlled drug delivery, and the current state-of-the-art technologies that allow the creation of novel 3D drug carriers at nano- and micro-scales.
Assessing multimedia similarity (1998)

In ttis paper we addrms the issue of s@uctural JIzdiIIzcdia siIzzZari@, mhlch is based on the re~ations between the individud objects that comprise a rnuItimedla documenti We propose a binary string encoding for lD relations which permits the automatic derivation of similarity measur~. T1'ethen etiend it to various r~oIution levels and many dimensions and show that reasoning on spatiotempord structure is si=wificantly facilitated in the new framework by applying it to multimedia presentation and motion similarity.
Angiotensin II stimulates the proliferation and biosynthesis of type I collagen in cultured murine mesangial cells. (1992)

A murine mesangial cell line (MMC) was established from the glomeruli of SJL mice to study the influence of angiotensin II (ANG II) on their growth and function in a serum-free culture. Murine mesangial cells exhibit the phenotypic characteristics of mesangial cells, including staining for desmin, vimentin, Thy 1, and types I and IV collagen by immunofluorescence. The addition of daily doses of 10(-6) to 10(-11) mol/l ANG II to MMCs also induced their proliferation in serum-free media. This effect on growth was independent of the presence of insulin in the media, and was receptor mediated, because the specific ANG II-receptor antagonist DuP 753 abolished proliferative growth. Angiotensin II also stimulated mainly the biosynthesis of type I collagen in our MMCs. Transfection of MMCs with chimeric genes containing enhancer/promoter elements for alpha 2(I) and alpha 1(IV) collagens linked to a chloramphenicol acetyltransferase reporter demonstrated that the stimulatory effect of ANG II for type I depends, at least to some extent, on an increase in transcription. These findings indicate collectively that ANG II in serum-free cultures can be a paracrine catalyst for the growth and biosynthesis of type I collagen in mesangial cells.
Technetium-99m HM-PAO-labeled leukocytes in detection of inflammatory lesions: comparison with gallium-67 citrate. (1989)

Forty-three patients with suspected benign, inflammatory, or infectious diseases were imaged with [99mTc]HM-PAO-labeled leukocytes and [67Ga]citrate. Technetium-99m leukocytes showed 22 true-positive, no false-positive, 19 true-negative, and two false-negative findings and [67Ga]citrate 23, 7, 12 and 1, respectively. The sensitivity, specificity, and accuracy values with 99mTc leukocytes were 92%, 100%, and 95%, and with [67Ga]citrate 96%, 63%, and 81%. Technetium-99m leukocyte scintigraphy has a promising future in comparison with [67Ga]citrate because of the ready availability of [99mTc]HM-PAO, the good image quality, more rapid results (within few hours), and the lower radiation exposure to the patient with 99mTc leukocytes. The usefulness of 99mTc leukocytes in chronic osteomyelitis needs further evaluation.
Cardioblast-intrinsic Tinman activity controls proper diversification and differentiation of myocardial cells inDrosophila (2006)

The NK homeobox gene tinman (tin) is required for the specification of the cardiac, visceral muscle and somatic muscle progenitors in the early dorsal mesoderm of Drosophila. Like its vertebrate counterpart Nkx2.5, the expression of tin is maintained in cardiac cells during cardiac maturation and differentiation; however, owing to the complete lack of a dorsal vessel in tin mutant embryos, the function of tin in these cells has not been defined. Here we show that myocardial cells and dorsal vessels can form even though they lack Tin, and that viable adults can develop, as long as Tin is provided in the embryonic precardiac mesoderm. However, embryos in which tin expression is specifically missing from cardial cells show severe disruptions in the normal diversification of the myocardial cells, and adults exhibit severe defects in cardiac remodeling and function. Our study reveals that the normal expression and activity of Tin in four of the six bilateral cardioblasts within each hemisegment of the heart allows these cells to adopt a cell fate as ;working' myocardium, as opposed to a fate as inflow tract (ostial) cells. This function of tin involves the repression of Dorsocross (Doc) T-box genes and, hence, the restriction of Doc to the Tin-negative cells that will form ostia. We conclude that tin has a crucial role within myocardial cells that is required for the proper diversification, differentiation, and post-embryonic maturation of cardiomyocytes, and we present a pathway involving regulatory interactions among seven-up, midline, tinman and Dorsocross that establishes these developmental events upon myocardial cell specification.
Biological mass spectrometry : proceedings of the Second International Symposium on Mass Spectrometry in the Health and Life Sciences, San Francisco, California, U.S.A., August 27-31, 1989 (1990)

The methods, instrumentation, opportunities and present focus of international research efforts involving the study of proteins, glycoconjugates and nucleic acids use mass spectrometry as a primary structural strategy rather than as an auxiliary technique. Not only is there established interest in the metabolism of endogenous and xenobiotic substances, per se, but also in the fact that when particular structures are metabolized, they form reactive electrophilic intermediates which may covalently bind to macromolecules, and eventually become manifest in the cell or organism as toxicity or chemical carcinogenesis. Additional important covalent modifications involve studies of chemical and photoaffinity labeling of macromolecules, studies of substrate and large molecules (receptor, enzyme, etc.), binding sites, interactions and membrane topography. In this volume, the authors explore new methods of tandem mass spectrometry with array detection systems which provide high accuracy in identification, are far more rapid than the automated Edman sequencing devices, and have comparable sensitivity.
Recognition and Activation of Rho GTPases by Vav1 and Vav2 Guanine Nucleotide Exchange Factors (2005)

Vav proteins are Rho GTPase-specific guanine nucleotide exchange factors (GEFs) that are distinguished by the tandem arrangement of Dbl homology (DH), Pleckstrin homology (PH), and cysteine rich domains (CRD). Whereas the tandem DH−PH arrangement is conserved among Rho GEFs, the presence of the CRD is unique to Vav family members and is required for efficient nucleotide exchange. We provide evidence that Vav2-mediated nucleotide exchange of Rho GTPases follows the Theorell−Chance mechanism in which the Vav2·Rho GTPase complex is the major species during the exchange process and the Vav2·GDP-Mg2+·Rho GTPase ternary complex is present only transiently. The GTPase specificity for the DH−PH−CRD Vav2 in vitro follows this order: Rac1 > Cdc42 > RhoA. Results obtained from fluorescence anisotropy and NMR chemical shift mapping experiments indicate that the isolated Vav1 CRD is capable of directly associating with Rac1, and residues K116 and S83 that are in the proximity of the P-loop and the guanine base either are part of this binding interface or undergo a conformational change in response to CRD binding. The NMR studies are supported by kinetic measurements on Rac1 mutants S83A, K116A, and K116Q and Vav2 CRD mutant K533A in that these mutants affect both the initial binding event of Vav2 with Rac1 (kon) and the rate-limiting dissociation of Vav2 from the Vav2·Rac1 binary complex (thereby influencing the enzyme turnover number, kcat). The results suggest that the CRD domain in Vav proteins plays an active role, affecting both the kon and the kcat for Vav-mediated nucleotide exchange on Rho GTPases.
Magnesium-Catalyzed Hydroboration of Pyridines (2011)

Reaction of catalytic quantities of a β-diketiminato n-butylmagnesium complex with pinacol–borane in the presence of pyridine derivatives provides facile access to borylated dihydropyridines. The reaction is applicable to a wide range of monocyclic and fused-ring pyridine derivatives and catalytic turnover is proposed to occur through a well-defined sequence of Mg–H/pyridine dearomatization and Mg–N/B–H sigma bond metathesis steps.
A Comparative Study on the Norms that Regulate Determining the Signification Threshold in Romania and Spain (2012)

The present study refers to the signification threshold, as a basic element which influences the development and quality of the whole financial audit process. At the beginning of this article we have determined the way in which have been taken over the ifs of the Directive 2006/43/EC regarding the taking over of the International Audit Standards in the national legislation in Romania and Spain. Next, I have realised a comparative analyses between the International Audit Standards referring to the signification threshold which is applied in Romania and the Technical Audit Norms which are applied in Spain, analyses where I have identified a series of differences. I have also underlined the news that is introduced by the International Audit Standards compared to the Technical Audit Norms in Spain regarding this theme. In the end of the article it is stated that adopting clarified ISA is not enough to improve the way of determining the signification threshold and it is underlined the necessity of appearing some regulations which would guide the auditors in framing the professional reasoning and establishing at least some minimum limits, which will lead to establishing a more homogenous signification
Amarogentin, a Naturally Occurring Secoiridoid Glycoside and a Newly Recognized Inhibitor of Topoisomerase I from Leishmania donovani (1996)

A MeOH extract of Swertia chirata found to inhibit the catalytic activity of topoisomerase I of Leishmania donovani was subjected to fractionation to yield three secoiridoid glycosides: amarogentin (1), amaroswerin (2), and sweroside (3). Amarogentin is a potent inhibitor of type I DNA topoisomerase from Leishmania and exerts its effect by interaction with the enzyme, preventing binary complex formation.
Structure and Dynamics of Polymer-Layered Silicate Nanocomposites (1996)

The static and dynamic properties of polymer-layered silicate nanocomposites are discussed in the context of polymers in confined media. Despite the topological constraints imposed by the host lattice, mass transport of the polymer into the silicate layers (at least in the case of essentially non-polar polystyrene) appears to be unhindered and exhibits mobility similar to that of the pure polymer. However, both the local and global dynamics of the polymer in the hybrids are dramatically different from those in the bulk. On a local scale, intercalated polymer chains exhibit higher flexibility along their backbone along with a marked suppression (or even absence) of cooperative dynamics typically associated with the glass transition. On a global scale, relaxation of polymer chains either tethered to or in close proximity (<1 nm as in intercalated hybrids) to the host surface are dramatically altered and parallel those of other intrinsically anisotropic materials such as block copolymers and liquid crystals.