gebhart/patrepeval huggingface dataset:
Melatonin prevents down-regulation of astrocytic phosphoprotein PEA-15 in ischemic brain injury (2011)

Melatonin functions as a free-radical scavenger and has a neuroprotective effect against ischemic brain damage. PEA-15 (phosphoprotein enriched in astrocytes 15) regulates various cellular processes including cell proliferation and apoptosis. In this study, we investigated whether melatonin regulates the levels of PEA-15 and the two phosphorylated forms of PEA-15 (Ser 104 and Ser 116) in a middle cerebral artery occlusion (MCAO)-induced injury model and neuronal cells exposed to glutamate. Adult male rats were treated with vehicle or melatonin (5 mg/kg) prior to MCAO, and cerebral cortex tissues were collected 24 h after MCAO. PEA-15 levels after ischemic brain injury were monitored using a proteomic approach. Melatonin pretreatment prevented the ischemic injury-induced reduction in PEA-15 levels. Moreover, Western blot analysis demonstrated that melatonin attenuated the ischemic injury-induced reduction in PEA-15, phospho-PEA-15 (Ser 104), and phospho-PEA-15 (Ser 116) levels. Neuronal cells exposed to glutamate showed decreased expression of PEA-15, phospho-PEA-15 (Ser 104), and phospho-PEA-15 (Ser 116), while melatonin pretreatment prevented the glutamate toxicity-induced decreases in the levels of these proteins. The reduction in the levels of phospho-PEA-15 proteins indicates the inhibition of anti-apoptotic function of PEA-15. Together, in vivo and in vitro results suggest that melatonin protects neurons against ischemic injury by maintaining levels of phospho-PEA-15 proteins.
Distinct kinetics of cytokine production and cytolysis in effector and memory T cells after viral infection (1999)

In the present study, naive T cells were compared with in vivo generated effector and memory T cells expressing the same TCR specific for lymphocytic choriomeningitis virus. Upon restimulation in vitro, the same minimal concentrations of the full agonist peptide p33 and also of weak and partial agonist peptides were required for proliferation of naive, effector and memory T cells, indicating no difference in threshold of activation. However, activation kinetics were distinct. While effector cytotoxic T cells exhibited immediate ex vivo lytic effector function, naive and memory T cells required 12 h and more exposure to antigen to develop lytic activity. However, both effector and memory T cells contained IFN-gamma mRNA in vivo and required less than 3 h for secretion of cytokines upon restimulation in vitro. In contrast, naive T cells did not contain IFN-gamma mRNA and required more than 12 h for cytokine secretion. Our results show that memory T cells exhibit a unique phenotype in that they produce cytokines and commit to proliferation as rapidly as effector cells, whereas they resemble naive T cells in the time requirement for development of cytolytic function.
The Biochemical Basis of an All-or-None Cell Fate Switch in <i>Xenopus</i> Oocytes (1998)

Xenopus oocytes convert a continuously variable stimulus, the concentration of the maturation-inducing hormone progesterone, into an all-or-none biological response-oocyte maturation. Here evidence is presented that the all-or-none character of the response is generated by the mitogen-activated protein kinase (MAPK) cascade. Analysis of individual oocytes showed that the response of MAPK to progesterone or Mos was equivalent to that of a cooperative enzyme with a Hill coefficient of at least 35, more than 10 times the Hill coefficient for the binding of oxygen to hemoglobin. The response can be accounted for by the intrinsic ultrasensitivity of the oocyte's MAPK cascade and a positive feedback loop in which the cascade is embedded. These findings provide a biochemical rationale for the all-or-none character of this cell fate switch.
The Effect of pH on Green Fluorescent Protein: a Brief Review (2001)

Green fluorescent protein (GFP) is rapidly becoming one of the most frequently employed molecular reporters. Its use in monitoring gene expression and protein localization has been well documented. Different mutational approaches have created numerous GFP variants with optimized expression, differing spectra, and differing pH sensitivity. This last characteristic, though still poorly understood mechanistically, has attracted an increasing amount of interest. To date, GFP variants have been developed with pKas ranging from 4.8 (T203I) to 8.0 (YFP-H148G/ T203Y). The objective of this review is to outline both the effect of pH on GFP fluorescence and the uses of GFP to study processes in different pH environments.
Assessment of the optimal atrioventricular delay in patients with dual chamber pacemakers using impedance cardiography and Doppler echocardiography (1999)

Impedance cardiography and Doppler echocardiography are two non-invasive methods to investigate the haemodynamics in dual chamber pacing. The purpose of the study was to assess the haemodynamic effects of different atrioventricular delays (AVDs). Second aim was the comparison of these established techniques to find the easiest method for optimal AVD selection. 36 patients with dual chamber pacemakers were tested at rest and 32 of them at a higher rate (90 bpm) pacing. We measured the stroke volume by impedance cardiography at various AVDs. Doppler echocardiography was used to determine the maximum velocity of aortic flow and its velocity-time-integral. The measurements show individually different optimal AVD between 78 and 300 ms. Compared with the most disadvantageous AVD we could improve the stroke volume at optimal AVD by 30.6 ± 24.7 % (at rest) and by 43.6 ± 18.9 % (at a higher pacing rate). These optimal AVDs were confirmed by measurements of maximum aortic flow and its velocity time integral, which were found to be in good correlation to the stroke volume measured by Impedance cardiography. The aortic flow and velocity time integral significantly increased at rest by 13.3 ± 10.1 % and 12.9 ± 9.7 % at higher rate pacing by 19.9 ± 15.8 % and 25.8 ± 19.7 % respectively. The optimal AVD for haemodynamics in dual chamber pacing is always an individual value. Impedance cardiography and Doppler echocardiography both provide this optimal AVD. J Clin Basic Cardiol 1999; 2: 237-40.
Adsorption of purified human cytomegalovirus and induction of early antigens in different cells (1982)

Different human and nonhuman cells were assayed for their capacity to absorb human cytomegalovirus (CMV Ad.169) and to support CMV infection in vitro. The CMV adsorptive capacity was assayed by measuring cell-bound radioactivity after addition of purified 3H- or 125I-labeled CMV or by a bioassay for residual infectious virus in the supernatant fluid. Many of the human and nonhuman cell types adsorbed CMV. Induction of CMV early nuclear antigens in the same cells was assayed by anticomplement immunofluorescence staining of fixed cells 1-3 days after infection. CMV early antigens were induced in the human and nonhuman cells that showed a high degree of CMV adsorption.
Isolation and characterization of the cyanogen bromide peptides from the αl(II) chain of bovine and human cartilage collagen (1973)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTIsolation and characterization of the cyanogen bromide peptides from the αl(II) chain of bovine and human cartilage collagenEdward J. Miller and Linda G. LundeCite this: Biochemistry 1973, 12, 17, 3153–3159Publication Date (Print):August 1, 1973Publication History Published online1 May 2002Published inissue 1 August 1973https://pubs.acs.org/doi/10.1021/bi00741a003https://doi.org/10.1021/bi00741a003research-articleACS PublicationsRequest reuse permissionsArticle Views168Altmetric-Citations103LEARN 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
Automated in situ measurement of cell‐specific antibody secretion and laser‐mediated purification for rapid cloning of highly‐secreting producers (2005)

Cloning of highly-secreting recombinant cells is critical for biopharmaceutical manufacturing, but faces numerous challenges including the fact that secreted protein does not remain associated with the producing cell. A fundamentally new approach was developed combining in situ capture and measurement of individual cell protein secretion followed by laser-mediated elimination of all non- and poorly-secreting cells, leaving only the highest-secreting cell in a well. Recombinant cells producing humanized antibody were cultured serum-free on a capture matrix, followed by staining with fluorescently-labeled anti-human antibody fragment. A novel, automated, high-throughput instrument (called LEAP) was used to image and locate every cell, quantify the cell-associated and secreted antibody (surrounding each cell), eliminate all undesired cells from a well via targeted laser irradiation, and then track clone outgrowth and stability. Temporarily sparing an island of helper cells around the clone of interest improved cloning efficiency (particularly when using serum-free medium), and helper cells were easily eliminated with the laser after several days. The in situ nature of this process allowed several serial sub-cloning steps to be performed within days of one another, resulting in rapid generation of clonal populations with significantly increased and more stable, homogeneous antibody secretion. Cell lines with specific antibody secretion rates of > 50 pg/cell per day (in static batch culture) were routinely obtained as a result of this cloning approach, often times representing up to 20% of the clones screened.
Isolation and characterization of a mutant of a methanol yeast, Candida boidinii S2, with higher formaldehyde productivity. (1985)

We isolated a mutant strain of a methanol-utilizing yeast, Candida boidinii S2, which shows improved formaldehyde productivity. The procedure for mutant screening consisted of; 1) induction of alcohol oxidase on a methanol-plate, 2) catabolite inactivation of alcohol oxidase on a glucose-plate, and 3) visualization of alcohol oxidase activity in a colony. One of the mutants, strain AOU-1, showed 1.7 times higher formaldehyde productivity and a higher growth rate on methanol than the parent strain. The high formaldehyde productivity was proved to be due to the high alcohol oxidase activity. No qualitative change of the enzyme was detected between the parent strain and mutant strain AOU-1. The high activity of mutant strain AOU-1 could be attributed to a quantitative change and a change in the rate of enzyme synthesis. Catabolite repression and inactivation of alcohol oxidase in the mutant were also discussed.
FORMATION OF HELICAL SUPER STRUCTURE FROM SINGLE-WALLED BILAYERS BY AMPHIPHILES WITH OLIGO-<scp>l</scp>-GLUTAMIC ACID-HEAD GROUP (1984)

Abstract Double-chain alkyl amphiphiles with oligo-l-glutamic acid-head group were prepared. These compounds were dispersed in water at pH 8 to 9 to form bilayer aggregates, in which helical and hollow structures were contained. New CD bands were observed in the solution.
Ion Exchange Equilibria between Glasses and Molten Salts and Thermodynamical Properties in Mixed Alkali Glasses (1986)

The isotherms in ion exchange equilibrium between alkali silicate glasses and molten salts have been determined for Na+-K+ ion exchange reactions. The distribution equilibria for alkali were obtained for some glasses with different alkali fractions in a series of mixed alkali glasses. The distribution curves at 500°C were almost the same for all glasses. However, at 350°C the distribution data were not represented by a single curve probably due to the fact that the exchange distribution is influenced by the starting composition. Thermodynamical approach was made on the basis of the exchange isotherms according to the Ekedahl analysis. The activity coefficient of each alkali ion at 500° and 350°C was derived from the experimental data, and the heat of mixing was calculated for an imaginary mixed system of two end-members (Na-glass/K-glass). Thermodynamical behavior of the glass is regarded as that of a regular solution above Tg. Then, alkali ion mobitity in mixed alkali glasses was discussed in term of mixing enthalpy, and the ion exchange kinetics was analyzed using activity coefficients of alkalis and other data.
EFFECT OF SOME ECOLOGICAL FACTORS ON THEGROWTH OF <I>ASPERGILLUS NIGER</I> AND <I>CLADOSPORIUM SPHAEROSPERMUM</I> (2013)

Indoor airborne fungi have been implicated in human health problems, damage to building materials, books, clothes and stored foods, which effected by different ecological factors. Aspergillus niger and Cladosporium sphaerospermum are the most dominant indoor airborne fungi were obtained from our previous study. The effect of normal indoor conditions (Temperature and Relative Humidity) on their growth was studied. Including their nutrients growth requirements. The PDA medium was the appropriate growth medium for Cl. sphaerospermum, with a significant difference at (p<0.05); where as GYA medium was the appropriate growth medium for A. niger, with no significant difference. The temperatures 25 and 30C favored colony diameter growth for Cl. sphaerospermum and A. niger, respectively with a significant difference at (p<0.05). The growth of Cl. sphaerospermum increased to reach its maximum at 100% RH. Whereas, A. niger prefers to grow at lower RH comparing to Cl. sphaerospermum to reach its maximum at 75% RH with a significant difference at (p<0.05). Controlling the normal indoor conditions can play a significant role in reducing the growth of indoor airborne fungi. Cl. sphaerospermum can be used as indicator fungi for the high humidity level in residences. The result has proved that keeping the humidity low enough can prevent fungi growth.
Diffusion approximation modeling for Markov modulated bursty traffic and its applications to bandwidth allocation in ATM networks (1998)

We consider a statistical multiplexer model, in which each of the K sources is a Markov modulated rate process (MMRP). This formulation allows a more general source model than the well studied "on-off" source model in characterizing variable bit rate (VBR) sources such as compressed video. In our model we allow an arbitrary distribution for the duration of each of the M states (or levels) that the source can take on. We formulate Markov modulated sources as a closed queueing network with M infinite-server nodes. By extending our earlier results we introduce an M-dimensional diffusion process to approximate the aggregate traffic of such Markov modulated sources. Under a set of reasonable assumptions we then show that this diffusion process can be expressed as an M-dimensional Ornstein-Uhlenbeck (O-U) process. The queueing behavior of the buffer content is analyzed by applying a diffusion process approximation to the aggregate arrival process. We show some numerical examples which illustrate typical sample paths, and autocorrelation functions of the aggregate traffic and its diffusion process representation. Simulation results validate our proposed approximation model, showing good fits for distributions and autocorrelation functions of the aggregate rate process and the asymptotic queueing behavior. We also discuss how the analytical formulas derived from the diffusion approximation can be applied to compute the equivalent bandwidth for real-time call admission control, and how the model can be modified to characterize traffic sources with long-range dependence.
Solving satisfiability and implication problems in database systems (1996)

Satisfiability, implication, and equivalence problems involving conjunctive inequalities are important and widely encountered database problems that need to be efficiently and effectively processed. In this article we consider two popular types of arithmetic inequalities, ( X op Y ) and ( X op C ), where X and Y are attributes, C is a constant of the domain or X , and op ∈{<, ≤, =, ≠, >, ≥). These inequalities are most frequently used in a database system, inasmuch as the former type of inequality represents a 0-join, and the latter is a selection. We study the satisfiability and implication problems under the integer domain and the real domain, as well as under two different operator sets ({<, ≤, =, ≥, >} and {<, ≤, =, ≠, ≥, >}). Our results show that solutions under different domains and/or different operator sets are quite different. Out of these eight cases, excluding two cases that had been shown to be NP-hard, we either report the first necessary and sufficient conditions for these problems as well as their efficient algorithms with complexity analysis (for four cases), or provide an improved algorithm (for two cases). These iff conditions and algorithms are essential to database designers, practitioners, and researchers. These algorithms have been implemented and an experimental study comparing the proposed algorithms and those previously known is conducted. Our experiments show that the proposed algorithms are more efficient than previously known algorithms even for small input. The C++ code can be obtained by an anonymous ftp from <archive.fiu.edu>.
Rapid identification of bacteria of the Comamonadaceae with amplified ribosomal DNA-restriction analysis (ARDRA) (1992)

Ribosomal rRNA gene fragments (rDNA) encompassing the 16S rDNA, the 16S-23S rDNA spacer region and part of the 23S rDNA of 95 strains belonging to 13 well-described taxa of the eubacterial family Comamonadaceae (beta subclass of the Proteobacteria or rRNA superfamily III) were enzymatically amplified using conserved primers. The fragments of approximately 2400 base pairs were subjected to restriction analysis. Restriction fragment length patterns obtained with HinfI enabled us to distinguish 9 of the 13 taxa studied. Restriction with CfoI was necessary to differentiate Acidovorax delafieldii from A. temperans and Hydrogenophaga flava from H. pseudoflava. The results indicate that amplified rDNA restriction analysis is a simple and reliable tool for the identification of bacterial species.
Inter-comparison of Laser Photoacoustic Spectroscopy and Gas Chromatography Techniques for Measurements of Ethene in the Atmosphere (2005)

Laser photoacoustic spectroscopy (LPAS) is highly suitable for the detection of ethene in air due to the overlap between its strongest absorption lines and the wavelengths accessible by high-powered CO2 lasers. Here, we test the ability of LPAS to measure ethene in ambient air by comparing the measurements in urban air with those from a gas chromatography flame-ionization detection (GC-FID) instrument. Over the course of several days, we obtained quantitative agreement between the two measurements. Over this period, the LPAS instrument had a positive offset of 330 +/- 140 pptv (parts-per-trillion by volume) relative to the GC-FID instrument, possibly caused by interference from other species. The detection limit of the LPAS instrument is currently estimated around 1 ppbv and is limited by this offset and the statistical noise in the data. We conclude that LPAS has the potential to provide fast-response measurements of ethene in the atmosphere, with significant advantages over existing techniques when measuring from moving platforms and in the vicinity of emission sources.
Liquid-crystal-filled gratings with high diffraction efficiency (1996)

To date, optical diffraction gratings filled with liquid crystals have not produced high (>50%) diffraction efficiencies in nonzero diffractive orders. Rigorous coupled-wave analysis indicates, however, that very high diffraction efficiencies (99% in single-wavelength polarized illumination) are theoretically feasible for this class of device, even when the devices employ rectangular grating profiles. These theoretical predictions with rectangular rather than blazed profiles imply simplified fabrication techniques for experimentally achieving high efficiencies by use of deep-etch submicrometer fabrication techniques.
Accelerating Technology Acceptance: Blurring the Lines (2005)

Abstract This paper describes the content and findings of a breakout session at the SPE Applied Technology Workshop held 15-16 March 2005, in Montgomery, Texas. The pace of technology adoption in the oil industry is widely acknowledged to be relatively slow. The purpose of the breakout session was to examine the extent to which contracting relationships between service companies and oil companies contributed to this problem, and what measures could be taken to improve these relationships. Framing the Problem. The session participants identified the most important factors that block the uptake of technology. These provided a backdrop against which to examine the contractual relationships. Current Practices. The participants then selected a number of relationship types that are widely used in the industry, including: conventional tendering; licensing; collaborative development work; the role of small technology providers; coventuring; and working interest participation. Views and Experience. Within the time constraints of the session each of the relationships types was debated individually, considering their good and bad features, and the circumstances under which they did and didn't tend to produce good results. Recommendations. Following the debates the most important observations were captured and recommendations for improvement were made. Each of these recommendations was then voted upon by the session participants to determine both its importance and feasibility to implement. These recommendations were then presented to the wider audience at the Workshop.