gebhart/patrepeval huggingface dataset:
Ionic Mechanisms Responsible for the Electrocardiographic Phenotype of the Brugada Syndrome Are Temperature Dependent (1999)

The Brugada syndrome is a major cause of sudden death, particularly among young men of Southeast Asian and Japanese origin. The syndrome is characterized electrocardiographically by an ST-segment elevation in V1 through V3 and a rapid polymorphic ventricular tachycardia that can degenerate into ventricular fibrillation. Our group recently linked the disease to mutations in SCN5A, the gene encoding for the alpha subunit of the cardiac sodium channel. When heterologously expressed in frog oocytes, electrophysiological data recorded from the Thr1620Met missense mutant failed to adequately explain the electrocardiographic phenotype. Therefore, we sought to further characterize the electrophysiology of this mutant. We hypothesized that at more physiological temperatures, the missense mutation may change the gating of the sodium channel such that the net outward current is dramatically augmented during the early phases of the right ventricular action potential. In the present study, we test this hypothesis by expressing Thr1620Met in a mammalian cell line, using the patch-clamp technique to study the currents at 32 degrees C. Our results indicate that Thr1620Met current decay kinetics are faster when compared with the wild type at 32 degrees C. Recovery from inactivation was slower for Thr1620Met at 32 degrees C, and steady-state activation was significantly shifted. Our findings explain the features of the ECG of Brugada patients, illustrate for the first time a cardiac sodium channel mutation of which the arrhythmogenicity is revealed only at temperatures approaching the physiological range, and suggest that some patients may be more at risk during febrile states.
DNA kinetics in microfabricated devices (2003)

The DNA kinetics in micro-capillary electrophoresis is presented. The mobility and diffusion coefficient of 14bp-DNA fragments as a function of concentration in two types of separation sieving matrices, hydroxyethylcellulose (HEC) polymer solution and agarose gel, are extracted through a series of experiments performed in microfabricated devices. In addition, the motion of a DNA plug through a miter bend and splitting a plug in a branch are quantitatively characterized. The concept of equivalent length is introduced to quantify the effect of a bend on the DNA plug motion. In a branching system, a simple kinematic relationship was discovered relating the quantity of DNA in each downstream branch to its relative channel cross-sectional area.
<title>Applications of ink-jet printing technology to BioMEMS and microfluidic systems</title> (2001)

Applications of microfluidics and MEMS (micro-electromechanical systems) technology are emerging in many areas of biological and life sciences. Non-contact microdispensing systems for accurate, high-throughput deposition of bioactive fluids can be an enabling technology for these applications. In addition to bioactive fluid dispensing, ink-jet based microdispensing allows integration of features (electronic, photonic, sensing, structural, etc.) that are not possible, or very difficult, with traditional photolithographic-based MEMS fabrication methods.Our single fluid and mutlifluid (MatrixJetT) piezoelectric microdispensers have been used for spot synthesis of peptides, production of microspheres to deliver drugs/biological materials, microprinting of biodegradable polymers for cell proliferation in tissue engineering requirements, and spot deposition for DNA, diagnostic immunoassay, antibody and protein arrays. We have created optical elements, sensors, and electrical interconnects by microdeposition of polymers and metal alloys. We have also demonstrated the integration of a reverse phase microcolumn within a piezoelectric dispenser for use in the fractionation of peptides for mass spectrometer analysis.
A pyrimidine-guanine sequence-specific ribonuclease fromRana catesbeiana(bullfrog) oocytes (1992)

A pyrimidine-guanine sequence-specific ribonuclease (RC-RNase) was purified from Rana catesbeiana (bullfrog) oocytes by sequential phosphocellulose, Sephadex G75, heparin Sepharose CL 6B and CM-Sepharose CL 6B column chromatography. The purified enzyme with molecular weight of 13,000 daltons gave a single band on SDS-polyacrylamide gel. One CNBr-cleaved fragment has a sequence of NVLSTTRFQLNT/TRTSITPR, which is identical to residues 59-79 of a sialic acid binding lectin from R. catesbeiana eggs, and is 71% homologous to residues 60-80 of an RNase from R. catesbeaina liver. The RC-RNase preferentially cleaved RNA at pyrimidine residues with a 3' flanking guanine under various conditions. The sequence specificity of RC-RNase was further confirmed with dinucleotide as substrates, which were analyzed by thin layer chromatography after enzyme digestion. The values of kcat/km for pCpG, pUpG and pUpU were 2.66 x 10(7) M-1s-1, 2.50 x 10(7) M-1s-1 and 2.44 x 10(6) M-1s-1 respectively, however, those for other phosphorylated dinucleotides were less than 2% of pCpG and pUpG. As compared to single strand RNA, double strand RNA was relatively resistant to RC-RNase. Besides poly (A) and poly (G), most of synthetic homo- and heteropolynucleotides were also susceptible to RC-RNase. The RC-RNase was stable in the acidic (pH 2) and alkaline (pH 12) condition, but could be inactivated by heating to 80 degrees C for 15 min. No divalent cation was required for its activity. Furthermore, the enzyme activity could be enhanced by 2 M urea, and inhibited to 50% by 0.12 M NaCl or 0.02% SDS.
Human platelets modulate edema formation in isolated rabbit lungs. (1989)

The role of platelet glucose-6-phosphate dehydrogenase (G-6-PD) in mediating the effects of human platelets on oxidant-induced edema in the isolated perfused rabbit lung was investigated using dehydroepiandrosterone, a specific steroidal inhibitor of G-6-PD. Xanthine oxidase (0.003 and 0.012 U/ml) caused lung edema that was attenuated by coinfusion of washed human platelets. Platelets that were incubated with DEA to inhibit G-6-PD activity augmented xanthine oxidase-induced lung edema and pulmonary hypertension at both doses of xanthine oxidase. Infusion of papaverine to maintain stable pulmonary artery (PA) pressures, incubation of G-6-PD-inhibited platelets with acetylsalicylate, or infusion of a thromboxane-prostaglandin endoperoxide receptor site antagonist, SQ 29548, into the lung perfusate prevented augmentation of lung edema and the PA pressor response by G-6-PD-inhibited platelets. It was concluded that antioxidant-intact platelets attenuate oxidant-induced lung edema by preventing increased membrane permeability, and that G-6-PD-inhibited platelets augment lung edema through hydrostatic mechanisms mediated by release of platelet cyclooxygenase products.
Physiological effects of deuterium on dogs (1961)

The physiological consequences of the deuterium isotope effect in large mammals were studied in two dogs, one of which was maintained at 20% concentration of D 2 O in the body fluids for 50 days, and the other at the toxic range of 33–35% for a brief period. Deuteration of the dogs was effected by replacement of ordinary water with deuterium oxide in both food and drink. Hemoglobin, hematocrit, and red blood cell count dropped but the white blood cell count was essentially unaffected although there was a progressive lymphopenia and granulocytosis. Serum glucose was decreased, especially at higher deuterium levels. Total serum cholesterol values were also diminished although the esters were essentially unchanged. Serum sodium and both NPN and BUN were within normal limits except for a terminal elevation of the latter. Serum potassium was slightly lowered for a brief period after 3 weeks. Electrocardiograms showed ST segment coving and elevation and an increase in the QT ratio that suggested nonspecific myocardial damage; these changes reverted to normal while the dog was still deuterated at a level of 20%. Both dogs exhibited neuromuscular disturbances, in one case definite weakness of the hind legs and in the other, fine muscle tremors.
Induction of early-phase endotoxin tolerance in athymic (nude) mice, B-cell-deficient (xid) mice, and splenectomized mice (1986)

Early-phase endotoxin tolerance was inducible in mice which were T cell deficient (nude), B cell deficient (xid), or asplenic, which suggests that these lymphoid cell subsets and the spleen do not contribute significantly to the induction of acquired lipopolysaccharide hyporesponsiveness. C3H/HeJ mice did not exhibit the hematopoietic changes observed in mice made endotoxin tolerant, which suggests that multiple mechanisms may underlie lipopolysaccharide hyporesponsiveness.
Doubling wireless channel capacity using co-polarised, co-located electric and magnetic dipoles (2002)

Experiments are described demonstrating the ability to realise independent information channels using co-located, co-polarised electric and magnetic dipoles in the presence of multipath propagation. The calculated information capacity is in good agreement with a random matrix channel model.
Muscle fibre conduction velocity in motor units of the human anterior tibial muscle: a new size principle parameter. (1987)

1. Twitch contractions were elicited in human anterior tibial muscle by intramuscular microstimulation of single motor axons with a bipolar needle electrode. The population of stimulated motor units studied was fairly representative for the muscle. 2. The conduction velocity of the fibres in the motor unit was calculated as the ratio between the electrode separation (15 mm) in a tripolar array of surface electrodes and the conduction delay of the motor unit potential along the electrode array. The motor unit conduction velocity ranged from 2.6 to 5.3 m/s with a mean of 3.7 m/s. 3. The contractile properties of the motor units were obtained by averaging the torque developed around the ankle joint. Twitch torques ranged from less than 10(-3) to 16 x 10(-3) N m, with a mean of 5.7 x 10(-3) N m. The twitch torque of the whole anterior tibial muscle was approximately 5 N m. Rise times were 47-80 m/s with a mean of 61 m/s, and half-relaxation times were 40-78 ms with a mean of 60 ms. 4. The mechanical properties of individual motor units were highly correlated (rise time and twitch torque: r = -0.81; rise time and half-relaxation time: r = 0.75; twitch torque and half-relaxation time: r = -0.81). 5. The motor unit conduction velocity was highly correlated to twitch torque (r = 0.87), rise time (r = -0.75) and half-relaxation time (r = -0.66). This indicates that the motor unit conduction velocity can be included in the family of interrelated 'size principle parameters'.
On the Role of Block Copolymers in Self-Assembly of Dense Colloidal Polymeric Systems (2003)

In the present work, we discuss the role of block copolymers in the self-assembly of diblock copolymers and monodisperse colloidal polymeric particles. Experiments for this type of system were carried out on colloidal dispersions of polystyrene (PS) colloidal particles and polystyrene−poly(2-vinylpyridine) (PS−PVP) block copolymers in ethanol. After complete solvent evaporation and upon annealing at temperatures above the glass transition temperature of both PS and PVP, the system self-assembles into closely packed PS polyhedrons surrounded by a PVP phase. A three-step mechanism is suggested for the rearrangement of the system, based on the segregation of block copolymers at the colloidal surface, penetration of PS blocks into the PS colloids, and frustration and relaxation of the PVP chains with subsequent relaxation of the colloid. A simple mathematical model is proposed for the packing frustration of the PS−PVP block copolymers, which allows a direct benchmark of the suggested mechanism with the experimental evidence for the colloidal system investigated.
A Comparison of Methods used for the Measurement of Organic Matter in Marine Sediment (1983)

Abstract The content of organic matter was determined in intertidal and subtidal sediments using different methods. The methods used measured the readily oxidizable organic matter (R.O.O.M.), the loss on ignition at two temperatures, 450°C (VS450) and 600°C (VS600), and the fraction oxidized by hydrogen peroxide (P.D.F.). The methods removed progressively more organic matter from a given sediment in the order R.O.O.M. < P.D.F. < VS450 < VS600. The differences between the values obtained by each method varied with the content of organic matter and were greatest at the lowest concentrations of organic matter. The relative proportions of labile and refractory organic matter varied depending upon the source of the sediment.
Stimulus Feature Selectivity in Excitatory and Inhibitory Neurons in Primary Visual Cortex (2007)

Although several lines of evidence suggest that stimulus selectivity in somatosensory and visual cortices is critically dependent on unselective inhibition, particularly in the thalamorecipient layer 4, no comprehensive comparison of the responses of excitatory and inhibitory cells has been conducted. Here, we recorded intracellularly from a large population of regular spiking (RS; presumed excitatory) and fast spiking (FS; presumed inhibitory) cells in layers 2-6 of primary visual cortex. In layer 4, where selectivity for orientation and spatial frequency first emerges, we found no untuned FS cells. Instead, the tuning of the spike output of layer 4 FS cells was significantly but moderately broader than that of RS cells. However, the tuning of the underlying synaptic responses was not different, indicating that the difference in spike-output selectivity resulted from differences in the transformation of synaptic input into firing rate. Layer 4 FS cells exhibited significantly lower input resistance and faster time constants than layer 4 RS cells, leading to larger and faster membrane potential (V(m)) fluctuations. FS cell V(m) fluctuations were more broadly tuned than those of RS cells and matched spike-output tuning, suggesting that the broader spike tuning of these cells was driven by visually evoked synaptic noise. These differences were not observed outside of layer 4. Thus, cell type-specific differences in stimulus feature selectivity at the first level of cortical sensory processing may arise as a result of distinct biophysical properties that determine the dynamics of synaptic integration.
Miniature ultrasonically powered wireless nerve cuff stimulator (2011)

We present a wireless neural stimulator composed of only three discrete components. The capsule was 8 mm long and was designed to be clasped directly upon a peripheral nerve. Power was supplied by low-intensity 1 MHz ultrasound transmitted into the body. The prototype was capable of generating currents in excess of 1 mA. For in vivo testing the device was implanted in a rat hind limb on the sciatic nerve, and when insonated with pulse intensities of 10-150 mW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> the stimulator excited motor axons inducing predictable contractions of the lower leg muscles.
Glycolipid ligands for selectins support leukocyte tethering and rolling under physiologic flow conditions. (1995)

Selectin interactions with glycolipids have been examined previously under static conditions, whereas physiologic interactions mediated by selectins take place under flow. We find that under physiologic flow conditions, sialyl Lewis(x) (sLe(x)) glycolipid and sialyl Lewisa (sLe(a)) neoglycolipid support tethering and rolling adhesions of Chinese hamster ovary (CHO) cells expressing E-selectin and lymphoid and myeloid cells expressing L-selectin. These selectin-mediated adhesions persist at the highest shear stresses that occur in postcapillary venules in vivo and occur at lower site densities than found for sLe(x) on neutrophils. The interactions are Ca(2+)-dependent and can be specifically and completely blocked with anti-selectin mAbs. Asialo nonfucosylated glycolipids are inactive, and sulfatide supports weak tethering, but not rolling, of L-selectin-expressing cells. Rolling velocities and resistance to detachment are related to the glycolipid site density and fall within the range measured for neutrophil and myeloid cell rolling on substrates containing purified selectins. These observations are the first indication that glycolipids can interact with selectins in physiologic flow conditions, and can contribute to rolling adhesions.
Fast and reliable estimation schemes in RFID systems (2006)

RFID tags are being used in many diverse applications in increasingly large numbers. These capabilities of these tags span from very dumb passive tags to smart active tags, with the cost of these tags correspondingly ranging from a few pennies to many dollars. One of the common problems that arise in any RFID deployment is the problem of quick estimation of the number of tags in the field up to a desired level of accuracy. Prior work in this area has focused on the identification of tags, which needs more time, and is unsuitable for many situations, especially where the tag set is dense. We take a different, more practical approach, and provide very fast and reliable estimation mechanisms. In particular, we analyze our estimation schemes and show that the time needed to estimate the number of tags in the system for a given accuracy is much better than schemes presented in related work. We show that one can estimate the cardinality of tag-sets of any size in near-constant time, for a given accuracy of estimation.
Proliferation, Hyperplasia, Neogenesis, and Neoplasia in the Islets of Langerhans (2007)

Pancreatic disease is responsible for significant morbidity and mortality as a result of pancreatic carcinoma and diabetes mellitus. Regulation of endocrine cell mass is thought to have a central role in the pathogenesis of both these diseases. Islet cell proliferation, hypertrophy, neogenesis, and apoptosis are the main determinants of endocrine cell mass in the pancreas, and their understanding has been improved by new clues of their genetic and molecular basis. Beta cells have attracted most research interest because of potential implications in the treatment of diabetes mellitus and hypoglycemic disorders. The processes that operate during pancreatic adaptation to a changing hormonal milieu are important in pancreatic carcinogenesis. There is evidence that somatostatin and its receptors are fundamental regulators of endocrine cell mass and are involved in islet tumorigenesis.
Appropriateness and delay to initiate therapy in ventilator-associated pneumonia (2005)

Inappropriate therapy (IT) and delayed initiation of appropriate therapy (DIAT) result in inadequate therapy in patients with ventilator-associated pneumonia (VAP). The aim of the current study was to assess the impact of DIAT in VAP. A total of 76 mechanically ventilated patients with bacteriologically confirmed VAP were prospectively evaluated in the intensive care unit of six hospitals in Buenos Aires, Argentina. Appropriate therapy was defined as coverage of all the identified pathogens by the antimicrobial therapy administered at the time of VAP clinical diagnosis. The clinical pulmonary infection score was measured during the 3 days before, at the onset and during the days which followed the onset of VAP. A total of 24 patients received adequate therapy; mortality was 29.2%. The remaining 52 patients received either IT (n = 16) or DIAT (n = 36); the mortality was 63.5% combined, and 75.0 and 58.3% for IT and DIAT, respectively (statistically significant compared with adequate therapy). Inappropriate therapy and delayed initiation of appropriate therapy increased the mortality of ventilator-associated pneumonia. Patients with inappropriate therapy and/or delayed initiation of appropriate therapy had a more gradual increase in clinical pulmonary infection score than those receiving adequate therapy, and this increase was found to occur prior to the time of the clinical diagnosis. In conclusion, these findings might provide the rationale for a trial of earlier initiation of therapy, based on clinical grounds in an effort to improve the outcome of patients with ventilator-associated pneumonia.
Carrier Phase Relative RAIM Algorithms and Protection Level Derivation (2010)

The concept of Relative Receiver Autonomous Integrity Monitoring (RRAIM) using time differential carrier phase measurements is investigated in this paper. The precision of carrier phase measurements allows for mitigation of integrity hazards by implementing RRAIM monitors with tight thresholds without significantly affecting continuity. In order to avoid the need for cycle ambiguity resolution, time differences in carrier phase measurements are used as the basis for detection. In this work, we examine RRAIM within the context of the GNSS Evolutionary Architecture Study (GEAS), which explores potential architectures for aircraft navigation utilizing the satellite signals available in the mid-term future with GPS III. The objectives of the GEAS are focused on system implementations providing worldwide coverage to satisfy LPV-200 operations, and potentially beyond. In this work, we study two different GEAS implementations of RRAIM. General formulas are derived for positioning, fault detection, and protection level generation to meet a given set of integrity and continuity requirements.
Enhanced Protective Antibody Responses to PspA after Intranasal or Subcutaneous Injections of PspA Genetically Fused to Granulocyte-Macrophage Colony-Stimulating Factor or Interleukin-2 (1998)

Antibody to pneumococcal surface protein A (PspA) has been shown to be protective for Streptococcus pneumoniae infections in mice. In an attempt to define a model for inducing protective antibody to PspA in the absence of adjuvant, we designed two genetic fusions, PspA-interleukin-2 [IL-2]) and PspA-granulocyte-macrophage colony-stimulating factor (GM-CSF). These constructs maintained high cytokine function in vitro, as tested by their activity on IL-2 or GM-CSF-dependent cell lines. While intranasal immunization with PspA induced no detectable anti-PspA response, both PspA-IL-2 and PspA-GM-CSF stimulated high immunoglobulin G1 (IgG1) antibody responses. Interestingly, only the PspA-IL-2, not the PspA-GM-CSF, construct stimulated IgG2a antibody responses, suggesting that this construct directed the response along a TH1-dependent pathway. Comparable enhancement of the anti-PspA response with similar isotype profiles was observed after subcutaneous immunization as well. The enhancement observed with PspA-IL-2 was dependent on IL-2 activity in that it was not seen in IL-2 receptor knockout mice, while PspA in alum induced high-titer antibody in these mice. The antibody was tested for its protective activity in a mouse lethality model using S. pneumoniae WU-R2. Passive transfer of 1:90 dilutions of sera from mice immunized with PspA-IL-2 and PspA-GM-CSF elicited protection of CBA/N mice against intravenous challenge with over 170 50% lethal doses of capsular type 3 strain WU2. Only 0.17 microg or less of IgG antibody to PspA was able to provide passive protection against otherwise fatal challenge with S. pneumoniae. The data demonstrate that designing protein-cytokine fusions may be a useful approach for mucosal immunization and can induce high-titer systemic protective antibody responses.
Fundus Flavimaculatus (1976)

Various stages of fundus flavimaculatus seen ophthalmoscopically were correlated with findings on electrophysiologic and psychophysical tests. A new classification of fundus flavimaculatus into stages recognizes the nuances in genetic expression and their correlation with findings on retinal function testing.