gebhart/patrepeval huggingface dataset:
Acute vagal modulation of electrophysiology of the atrial and pulmonary veins increases vulnerability to atrial fibrillation (2010)

Vagal activity is thought to influence atrial electrophysiological properties and play a role in the initiation and maintenance of atrial fibrillation (AF). We evaluated the effects of acute vagal stimulation on atrial conduction, refractoriness of atrial and pulmonary veins (PVs) and inducibility of AF. An open-chest epicardial approach was performed in New Zealand White rabbits with preserved autonomic innervation. Atrial electrograms were obtained with four unipolar electrodes placed epicardially along the atria (n = 22) and an electrode adapted to the proximal left PV (n = 10). The cervical vagus nerve was stimulated with bipolar platinum electrodes (20 Hz). Epicardial activation was recorded in sinus rhythm, and effective refractory periods (ERPs), dispersion of refractoriness and conduction times from high-lateral right atrium (RA) to high-lateral left atrium (LA) and PVs assessed at baseline and during vagal stimulation. Burst pacing (50 Hz, 10 s), alone or combined with vagal stimulation, was applied to the right (RAA) and left atrial appendage (LAA) and PVs to induce AF. At baseline, ERPs were lower in PVs than in LA and LAA, but did not differ significantly from RA and RAA, and there was a significant delay in the conduction time from RA to PVs compared with the activation time from RA to LA (P < 0.01). During vagal stimulation, ERP decreased significantly at all sites, without significant differences in the dispersion of refractoriness, and the atrial conduction times changed from 39 ± 19 to 49 ± 9 ms (RA to PVs; n.s.) and from 14 ± 7 to 28 ± 12 ms (RA to LA; P = 0.01). Induction of AF was reproducible in 50% of cases with 50 Hz and in 82% with 50 Hz combined with vagal stimulation (P < 0.05). During vagal stimulation, AF cycle length decreased at all sites, and AF duration changed from 1.0 ± 0.9 to 14.0 ± 10.0 s (P < 0.01), with documentation of PV tachycardia in three cases. In 70% of the animals, AF ceased immediately after interruption of vagal stimulation. We conclude that in the intact rabbit heart, vagal activity prolongs interatrial conduction and shortens atrial and PV ERP, contributing to the vulnerability to the induction and maintenance of AF. This model may be useful in the assessment of the autonomic influence in the mechanisms underlying AF.
Lubricating Ability of Langmuir-Blodgett Films as Boundary Lubricating Films on Articular Surfaces. (1996)

Frictional behavior in sliding pairs of pig articular cartilage and glass plate has been studied to elucidate the tribological role of constituents in a synovial fluid and a surface layer of the articular cartilage. Pig synovial fluid and water solution of hyaluronic acid were used as lubricants. The synovial fluid had a significantly superior lubricating ability to a sodium hyaluronate solution of equivalent viscosity under physiologically high load condition. The superiority of the synovial fluid seems to be responsible for the boundary lubricating ability of constituents other than hyaluronic acid. Langmuir-Blodgett films of phospholipid (Lα-dipalmitoyl phosphatidylcholine, Lα-DPPC) on the glass plate maintained low and stable friction, depending on the number of film layers. In conditions of mixed films containing γ-globulin and Lα-DPPC, the frictional behavior was improved by increasing the quantity of γ-globulin. A model of the boundary lubricating mechanism is proposed in which the effective adsorbed film is composed of proteins, phospholipids and other conjugated constituents on the articular surfaces, and controlled by hydrophobic groups in those amphiphiles.
The spatial distribution of carbon dioxide in rooms with particular application to classrooms (2013)

In most buildings, occupants are the main source of indoor carbon dioxide (CO 2 ) due to exhalation. Although CO 2 is not considered to pose serious health risks to occupants, elevated levels of CO 2 may serve as an indicator of insufficient ventilation. This study examines how CO 2 is distributed within a complex indoor environment of a classroom and how this distribution is affected by different parameters. Measuring CO 2 concentrations at a single location or height may not act as a true representation of an entire space, unless it is measured in a very small confined space. In this study, it was observed that higher CO 2 concentration values can be found at higher levels in a room and not only at a height between 1 m and 1.2 m as claimed by many researchers. Therefore, if CO 2 concentration levels vary significantly, deviations from the average measured values could become large. It was also found that the CO 2 concentration reflects the dynamic relationship among the occupants, their activity levels and occupancy periods. The findings present a useful contribution for future researchers to efficiently and strategically design experimental set ups with well-organised positioning of sensors for CO 2 monitoring purposes.
Mechanisms of vascular damage in SSc--implications for vascular treatment strategies (2008)

Vascular abnormalities are a major component of SSc, but little is known about the events or mechanisms that initiate vascular injury and prevent its repair. In SSc, angiogenesis is incomplete or lacking despite the increased expression of a large array of pro-angiogenic factors such as VEGF. Conflicting results have recently been published concerning the presence and role of vasculogenesis and circulating endothelial progenitor cells in SSc. It remains to be established if these endothelial progenitor cells are a marker of endothelial disease or a cause of insufficient vascular repair. Human mesenchymal stem cells (MSCs) may be an alternative source for endothelial progenitor cells, and it has been observed that the angiogenic potential of endothelial-like MSCs is reduced. Other mechanisms of vascular damage include oxidative stress and factors released from activated platelets. In addition, growth factors such as ET-1 and PDGF induce proliferation of vascular smooth muscle cells resulting in intimal thickening. For the development of new therapeutic strategies, it is important to realize that the different vascular pathologies--uncompensated loss of capillaries on one hand and vascular remodelling with a proliferative vasculopathy on the other--might require different treatment approaches.
An accurate air temperature measurement system based on an envelope pulsed ultrasonic time-of-flight technique (2007)

A new microcomputer based air temperature measurement system is presented. An accurate temperature measurement is derived from the measurement of sound velocity by using an ultrasonic time-of-flight (TOF) technique. The study proposes a novel algorithm that combines both amplitude modulation (AM) and phase modulation (PM) to get the TOF measurement. The proposed system uses the AM and PM envelope square waveform (APESW) to reduce the error caused by inertia delay. The APESW ultrasonic driving waveform causes an envelope zero and phase inversion phenomenon in the relative waveform of the receiver. To accurately achieve a TOF measurement, the phase inversion phenomenon was used to sufficiently identify the measurement pulse in the received waveform. Additionally, a counter clock technique was combined to compute the phase shifts of the last incomplete cycle for TOF. The presented system can obtain 0.1% TOF resolution for the period corresponding to the 40 kHz frequency ultrasonic wave. Consequently, with the integration of a humidity compensation algorithm, a highly accurate and high resolution temperature measurement can be achieved using the accurate TOF measurement. Experimental results indicate that the combined standard uncertainty of the temperature measurement is approximately 0.39 degrees C. The main advantages of this system are high resolution measurements, narrow bandwidth requirements, and ease of implementation.
Coupling of poly(ethylene glycol) to albumin under very mild conditions by activation with tresyl chloride: characterization of the conjugate by partitioning in aqueous two‐phase systems (1990)

Poly(ethylene glycol) activated with tresyl chloride has been covalently linked to albumin as a result of a 2-h incubation in 0.05 M sodium phosphate buffer, pH 7.5, containing 0.125 M sodium chloride (0.344 OSM). The coupling of poly(ethylene glycol) to albumin was demonstrated by the increase in the partition coefficient of the protein in poly(ethylene glycol)-dextran aqueous two-phase systems. A linear relationship between the log of the partition coefficient of the poly(ethylene glycol)-albumin conjugate and the degree of modification (measured as the amino groups consumed during the coupling step) has been demonstrated. Countercurrent distribution in the two-phase system showed that poly(ethylene glycol)-albumin was heterogeneous with respect to its partitioning behavior, indicating that the albumin was not uniformly modified with poly(ethylene glycol).
Glycosylation Profiling of Heterologous Proteins (1998)

The methylotrophic yeast Pichia pastoris has been widely exploited for its high-level expression of heterologous proteins by recombination of gene sequences of interest with the methanol-inducible alcohol oxidase gene (AOX1) promoter (1–3). Secreted and cytoplasmic expression of heterologous proteins at levels equivalent to Escherichia coli and significantly higher than in Saccharomyces cerevisiae has been achieved (4). In addition, P. pastoris cultures can be easily scaled up to high cell densities, and as a result, yields are also high on a volumetric basis (e.g., 12 g/L, for tetanus toxin fragment C [5], 2.5 g/L for invertase [6], 2.5 g/L for α-amylase [7]). Secreted products can comprise more than 80% of the protein in the medium (6). However, secretion is a complex process that is not only dependent on gene dosage, but also on other factors, such as signal sequence recognition and processing, proteolysis, and glycosylation.
Improved Pharmacokinetics and Reduced Antibody Reactivity of Lysostaphin Conjugated to Polyethylene Glycol (2003)

Lysostaphin is a 27-kDa endopeptidase that enzymatically disrupts the cell wall of Staphylococcus aureus and is a promising candidate for treating S. aureus blood-borne infections. It would be extremely useful to define conditions that would both increase lysostaphin's in vivo half-life to allow for more effective tissue distribution and reduce its immunogenicity. Conjugation of polyethylene glycol (PEG) to lysostaphin (PEGylation) was investigated as a means to accomplish these goals. Rather than using linear forms of PEG, branched PEGs were chosen as the initial candidates because their large spatial volumes prevent entry of the polymer into the enzyme's active sites, which could potentially reduce enzymatic function. Enzymatic activity for most PEGylated lysostaphins was reduced, but these compounds were still considerably active compared to unconjugated lysostaphin, with conjugates that had lower degrees of PEG modification having greater activity than those with higher degrees. PEGylated lysostaphin injected intravenously had a serum drug half-life of up to 24 h and resulted in much higher plasma drug concentrations than an equal dose of unconjugated lysostaphin, which had a half-life of less than 1 h. Finally, reduced binding affinity was shown for PEGylated lysostaphin in an antilysostaphin capture enzyme-linked immunosorbent assay, with some PEG-lysostaphin conjugates having binding affinities that were reduced more than 10-fold compared to unconjugated lysostaphin. These findings demonstrate that PEGylation of lysostaphin, while diminishing its S. aureus killing activity, results in prolonged serum drug persistence and reduced antibody binding. These features should significantly enhance lysostaphin's therapeutic value as an intravenous "antibiotic" against S. aureus.
Highly Efficient Isolation of Populus Mesophyll Protoplasts and Its Application in Transient Expression Assays (2012)

This study established a method for efficient isolation of protoplasts from Populus leaf and demonstrated the efficacy of using Populus protoplast transient expression assays as an in vivo system to characterize genes and pathways.
Spaceborne synthetic-aperture imaging radars: Applications, techniques, and technology (1982)

In the last four years, the first two Earth-orbiting, space-borne, synthetic-aperture imaging radars (SAR) were successfully developed and operated. This was a major achievement in the development of spaceborne radar sensors and ground processors. The data acquired with these sensors extended the capability of Earth resources and ocean-surface observation into a new region of the electromagnetic spectrum. This paper is a review of the different aspects of spaceborne imaging radars. It includes a review of: 1) the unique characteristics of space-borne SAR systems; 2) the state of the art in spaceborne SAR hardware and SAR optical and digital processors; 3) the different data-handling techniques; and 4) the different applications of spaceborne SAR data.
Formation of V-shaped pits in InGaN/GaN multiquantum wells and bulk InGaN films (1998)

InGaN/GaN multiquantum well structures and bulk InGaN films grown on (0001) sapphire substrate were investigated by cross-sectional transmission electron microscopy and double crystal x-ray diffraction. Highly strained InGaN layers with a high In mole fraction were found to contain V-shaped surface pits with (10–11) facet planes on pure or mixed screw treading dislocations. Phase separation was also found on thick InGaN/GaN superlattices and bulk InGaN layers. The mechanism of the surface pit formation was discussed in terms of strain energy and surface mobility of InGaN.
Neurogenic Inflammation in Human and Rodent Skin (2001)

The combination of vasodilation and protein extravasation following activation of nociceptors has been termed "neurogenic inflammation." In contrast to rodents, no neurogenic protein extravasation can be elicited in healthy human skin. Dermal microdialysis has considerably increased our knowledge about neurogenic inflammation in human skin, including the involvement of mast cells.
Safety and Efficacy of Ferric Carboxymaltose in Anemic Pregnant Women: A Retrospective Case Control Study (2015)

Background. Anemia during pregnancy is commonly caused by iron deficiency and can have severe consequences for both the mother and the developing fetus. The aim of this retrospective study was to assess the safety and efficacy of intravenous ferric carboxymaltose (FCM) in pregnant women. Methods. All women treated with FCM for anemia during pregnancy between 2010 and 2012 at our institution were included. A matched control group was selected, including women who either were nonanemic or had anemia but were not considered for intravenous iron. Main outcome measures were maternal safety and pregnancy outcomes. Results. The study included 128 patients (FCM: 64; control: 64). Median FCM dose was 1000 mg and median gestational age at the time of first treatment was 34 weeks and 6 days. Median Hb increased from 8.4 g/dL (interquartile range 7.7; 8.9 g/dL) at the first FCM administration to 10.7 g/dL (9.8; 11.5 g/dL; n = 46 with available Hb at delivery) at the time of delivery, achieving levels similar to those in the control group (10.8 g/dL [9.8; 11.8 g/dL; n = 48]). No treatment-related adverse events were reported and no statistically significant differences in pregnancy outcomes were observed between groups. Conclusions. Within the limitations of this case control study, FCM was a safe and efficient treatment of anemia during pregnancy.
Inhibition of the fusion-inducing conformational change of influenza hemagglutinin by benzoquinones and hydroquinones (1993)

Influenza hemagglutinin (HA) undergoes a conformational change that is required for viral entry. The rearrangement includes exposure of the fusion peptide, a hydrophobic segment buried in the trimer interface of the native protein. Since fusion peptide release triggers the membrane fusion event crucial for viral replication, inhibition of fusion peptide exposure should prevent infection. We reasoned that small molecules that bind to HA and stabilize its nonfusogenic conformation would block viral activity. A computer-assisted method was used to select putative HA ligands. One of the selected compounds, 4A,5,8,8A-tetrahydro-5,8-methano-1,4-naphthoquinone, prevented the conversion of X31 HA to a conformation recognized by alpha-fusion peptide antisera. Several derivatives of this compound, including both benzoquinones and hydroquinones, also showed inhibition. The most effective compounds tested have IC50S between 1 and 20 microM. Representative compounds also inhibited virus-induced syncytia formation, HA-mediated hemolysis, and viral infectivity in vitro. The inhibitors are attractive leads for the development of antiviral drugs and can serve as probes of the mechanism of the conformational change of HA.
Antimicrobial treatment of peri‐implant infections (1992)

The purpose of this study was to investigate the possibility of antimicrobial treatment of peri-implant infections associated with a periodontitis-like subgingival microbiota. Nine partially or fully edentulous patients with titanium hollow cylinder implants were selected which showed loss of bone and probing depths > or = 5 mm on one or several implants after at least 6 months following installation. They also yielded subgingival microbial samples with > or = 10(6) CFU/ml, including > or = 20% gram-negative anaerobic bacteria. The treatment included mechanical cleaning, irrigation of all peri-implant pockets > 3 mm with 0.5% chlorhexidine and systemic antimicrobial therapy (1000 mg ornidazole for 10 consecutive days). After therapy, bleeding scores decreased immediately and, over a one-year observation period, remained significantly lower than before treatment. A significant gradual reduction in mean probing depths was detected over this one-year period; only one case showed no improvement of local probing depth. Microbiological parameters indicated an instantaneous quantitative and qualitative change following treatment. Subsequently, several of these parameters tended to shift back towards pretreatment values. In the second half of the observation period, however, this tendency was reversed, and levels significantly different from baseline were eventually established. This study demonstrated that treatment aiming at reducing the subgingival bacterial mass and suppressing the anaerobic segment had a beneficial effect in patients suffering from peri-implantitis.
A chemical model for the cooperation of sulfates and carboxylates in calcite crystal nucleation: Relevance to biomineralization (1987)

Acidic matrix macromolecules involved in regulation of biological crystal growth often contain aspartic acid-rich domains and covalently bound sulfated polysaccharides. We propose that sulfates and beta-sheet structured carboxylates cooperate in oriented calcite crystal nucleation. The sulfates concentrate calcium, creating the supersaturation necessary for nucleation on the structured carboxylate domains. An artificial model, composed of sulfonated polystyrene surfaces and adsorbed beta-sheet poly(aspartate), demonstrates that the two components indeed act cooperatively with respect to two independent assays, both by induction of calcite nucleation off the (001) plane and by calcium association. Evidence is presented that a purified organic matrix acidic glycoprotein from mollusk shells may behave in vitro in a similar way.
Peripheral markers in testing pathophysiological hypotheses and diagnosing Alzheimer's disease (1998)

Alterations in amyloid precursor protein (APP) metabolism, calcium regulation, oxidative metabolism, and transduction systems have been implicated in Alzheimer's disease (AD). Limitations to the use of postmortem brain for examining molecular mechanisms underscore the need to develop a human tissue model representative of the pathophysiological processes that characterize AD. The use of peripheral tissues, particularly of cultured skin fibroblasts derived from AD patients, could complement studies of autopsy samples and provide a useful tool with which to investigate such dynamic processes as signal transduction systems, ionic homeostasis, oxidative metabolism, and APP processing. Peripheral cells as well as body fluids (i.e., plasma and CSF) could also provide peripheral biological markers for the diagnosis of AD. The criteria required for a definite diagnosis of AD presently include clinical criteria in association with histopathologic evidence obtained from biopsy or autopsy. Thus, the use of peripheral markers as a diagnostic tool, either to predict or at least to confirm a diagnosis, may be of great importance.
Modulation of promoter occupancy by cooperative DNA binding and activation-domain function is a major determinant of transcriptional regulation by activators in vivo. (1996)

Binding of transcriptional activators to a promoter is a prerequisite process in transcriptional activation. It is well established that the efficiency of activator binding to a promoter is determined by the affinity of direct interactions between the DNA-binding domain of an activator and its specific target sequences. However, I describe here that activator binding to a promoter is augmented in vivo by the effects of two other determinants that have not been generally appreciated: (i) the number of activator binding sites present in a promoter and (ii) the potency of activation domains of activators. Multiple sites within a promoter can cooperatively recruit cognate factors regardless of whether they contain an effective activation domain. This cooperativity can result in the synergistic activation of transcription. The second effect is the enhancement of activator binding to a promoter by the presence of activation domains. In this case, activation domains are not simply tethered to the promoter by the DNA-binding domain but instead assist the DNA-binding domain being tethered onto the promoter. This effect of activation domains on DNA binding is instrumental in determining how potent activators can induce steep transcriptional increases at low concentrations.
A comparison of the residual effects of zaleplon and zolpidem following administration 5 to 2 h before awakening (1999)

The present results demonstrate that zaleplon at the dose of 10 mg is free of residual hypnotic or sedative effects when administered nocturnally as little as 2 h before waking in normal subjects. In contrast, residual effects of zolpidem are still apparent on objective assessments up to 5 h after nocturnal administration, longer than has been reported from studies involving daytime administration.
Multiphasic MDCT Enhancement Pattern of Hepatocellular Carcinoma Smaller Than 3 cm in Diameter: Tumor Size and Cellular Differentiation (2009)

The prevalent enhancement patterns of HCC smaller than 3 cm on multiphasic MDCT scans differed depending on tumor size and cellular differentiation. HCCs smaller than 2 cm and well-differentiated HCCs frequently had atypical enhancement patterns.