gebhart/patrepeval huggingface dataset:
POLYKETIDE SYNTHESIS: Prospects for Hybrid Antibiotics (1993)

Polyketides fall into two structural classes: aromatic and complex. The former are built mainly from acetate units through a reiterative process wherein the beta-carbonyl groups formed after each condensation cycle are left largely unreduced. Complex polyketides are composed of acetates, propionates, or butyrates, and the extent of beta-carbonyl reduction varies from one cycle to the next. Two themes for polyketide synthases are emerging. Aromatic PKSs are determined by four to six genes encoding mono- or bifunctional enzymes; one PKS complex is used for all synthesis steps. Complex PKSs are composed of several multifunctional polypeptides that contain enzymatic domains for the condensation and reduction steps; each domain is used at a unique step in the pathways, and the extent of beta-carbonyl processing depends on the functional domains operating at that cycle. Mutations rendering certain domains nonfunctional have been introduced into genes for complex polyketides, resulting in the production of novel molecules.
Background subtraction techniques: a review (2005)

Background subtraction is a widely used approach for detecting moving objects from static cameras. Many different methods have been proposed over the recent years and both the novice and the expert can be confused about their benefits and limitations. In order to overcome this problem, this paper provides a review of the main methods and an original categorisation based on speed, memory requirements and accuracy. Such a review can effectively guide the designer to select the most suitable method for a given application in a principled way. Methods reviewed include parametric and non-parametric background density estimates and spatial correlation approaches.
Improved vector system for constructing transcriptional fusions that ensures independent translation of lacZ (1990)

An improved vector system has been developed for the in vitro construction of transcriptional fusions to lacZ. The principal feature is an RNaseIII cleavage site inserted between the polylinker cloning site and the promoterless lacZ gene. When these vectors are used to construct transcriptional fusions, the subsequent cleavage of the hybrid mRNA at the RNaseIII site generates an unchanging 5' end for the lacZ mRNA. In contrast to earlier vectors, this feature helps to ensure independent translation of the lacZ mRNA and, thus, the level of beta-galactosidase produced should accurately reflect the frequency of transcription of the upstream DNA sequences. Additional modifications of the vectors include removal of a weak transcriptional terminator between the cloning site and lacZ, insertion of a terminator downstream of lac, and alteration of restriction endonuclease cleavage sites to facilitate the in vitro construction of fusions. Both multicopy plasmid (pTL61T) and single-copy lambda (lambda TL61) vectors have been assembled. These vectors should be generally useful in scanning for transcriptional regulatory signals.
Design of HIV Vectors for Efficient Gene Delivery into Human Hematopoietic Cells (2002)

Vectors derived from human immunodeficiency virus (HIV) hold promise for efficient gene delivery into human hematopoietic cells. In this study, HIV vectors containing different combinations of cis-acting elements, including the HIV central flap sequence, and the woodchuck posttranscriptional regulatory element (WPRE) in combination with two different promoters, were used to transduce primary human lymphocytes and cord blood CD34+ progenitor cells. The effect of these elements on the transduction efficiency and transgene expression was systematically evaluated. The results demonstrate that with the combination of flap, WPRE sequences, and the promoter derived from spleen focus-forming virus (SFFV), a foreign gene can be efficiently delivered into primary human T lymphocytes and cord blood CD34+ cells. The study establishes the parameters for proper vector design to efficiently deliver foreign genes into human hematopoietic cells.
Ultrastretchable Fibers with Metallic Conductivity Using a Liquid Metal Alloy Core (2012)

Abstract The fabrication and characterization of fibers that are ultrastretchable and have metallic electrical conductivity are described. The fibers consist of a liquid metal alloy, eutectic gallium indium (EGaIn), injected into the core of stretchable hollow fibers composed of a triblock copolymer, poly[styrene‐ b ‐(ethylene‐ co ‐butylene)‐ b ‐styrene] (SEBS) resin. The hollow fibers are easy to mass‐produce with controlled size using commercially available melt processing methods. The fibers are similar to conventional metallic wires, but can be stretched orders of magnitude further while retaining electrical conductivity. Mechanical measurements with and without the liquid metal inside the fibers show the liquid core has a negligible impact on the mechanical properties of the fibers, which is in contrast to most conductive composite fibers. The fibers also maintain the same tactile properties with and without the metal. Electrical measurements show that the fibers increase resistance as the fiber elongates and the cross sectional area narrows. Fibers with larger diameters change from a triangular to a more circular cross‐section during stretching, which has the appeal of lowering the resistance below that predicted by theory. To demonstrate their utility, the ultrastretchable fibers are used as stretchable wires for earphones and for a battery charger and perform as well as their conventional parts.
Ectopic PDX-1 Expression Directly Reprograms Human Keratinocytes along Pancreatic Insulin-Producing Cells Fate (2011)

These findings constitute the first demonstration of human ectoderm cells to endoderm derived pancreatic cells transdifferentiation. The study represents a proof of concept which suggests that transcription factors induced reprogramming is wider and more general developmental process than initially considered. These results expanded the arsenal of adult cells that can be used as a cell source for generating functional endocrine pancreatic cells. Directly reprogramming somatic cells into alternate desired tissues has important implications in developing patient-specific, regenerative medicine approaches.
Influence of spray drying manufacturing parameters on quality of losartan potassium microspheres. (2014)

A general aim of the research was to develop a technology of manufacturing microspheres with losartan potassium as an active substance, and Eudragit L30D55 as a matrix with the use of spray drying technique. During the first step of the study, optimal values of parameters in spray drying process were established (i.e., operating temperature, peristaltic pump performance, aspiration value). Those values have a crucial effect on morphological parameters, and the size and homogeneity of received particles. In the obtained microspheres, the activity of excipients, which modify morphological properties of microspheres, were tested. Additionally, we studied the impact of the type and amount of plasticizer, as well as the amount of an adopted polymer in proportion to dry matter of losartan potassium, on quality of final product. Triethyl citrate and citric acid, plasticizers tested in reported studies, were also verified. A detailed study of the influence of both plasticizers on the qualities of microspheres containing losartan potassium on Eudragit L30D55 matrix indicated a positive influence of triethyl citrate and a negative influence of citric acid on morphological properties, shape and size of particles. The application of optimal parameters of spray drying and triethyl citrate as a plasticizer in the amount of 10 to 15% allows to obtain microspheres from 1.27 to 7.24 μm.
Ultrasonic sensors for chemical and process plant (1997)

Ultrasound and its properties nature of ultrasound ultrasonic optics generation and detection of ultrasound piezoelectric transducers other ultrasonic transducers electronics and signal processing description of ultrasonic sensors point level detectors (and some continuous level detectors) sensors where the velocity of ultrasound is determined determination of flow velocity sonar attenuation, scattering and acoustic impedance acoustic emission. Appendices: some factors which influence the velocity of ultrasound the mechanisms of attenuation of ultrasound ultrasonic waveguides piezoelectric materials suppliers
Piroxicam decreases postirradiation colonic neoplasia in the rat (1990)

This study evaluated the effects of the nonsteroidal antiinflammatory agent piroxicam on chronic radiation proctitis in the rat. Forty female Wistar rats received a 2250-cGy dose of irradiation to the distal 2 cm of the colon. Twenty received piroxicam 8.0 mg/kg orally 30 minutes before exposure and 24 hours after exposure; 20 rats served as irradiated controls. All animals were evaluated by colonoscopy 1 and 3 weeks postexposure and every third week until death or killing at 1 year. At killing, colons were removed for light microscopic examination. One year postirradiation results showed no differences in mortality, vascular changes, acute inflammation, colitis cystica profunda, or rectal stricture between the control and piroxicam-treated groups. However, at 1 year postirradiation the control group demonstrated neoplasia in 15 of 19 animals compared with eight of 20 animals in the piroxicam-treated group. The first endoscopic appearance of colonic neoplasm occurred at 15 weeks postirradiation in one control irradiated rat whereas the first evidence of endoscopic neoplasm in the piroxicam-treated group did not occur until 36 weeks postirradiation. Histologic examination documented a tendency toward a greater presence of adenocarcinomas in the control group compared with the piroxicam-treated group. The authors conclude that piroxicam treatment significantly decreased the incidence of colonic neoplasia in general as well as delayed the endoscopic appearance of colonic neoplasia in rats after pelvic irradiation.
Breath-based diagnosis of fungal infections (2017)

Invasive aspergillosis and other invasive fungal infections are associated with significant morbidity and mortality in immunocompromised patients, in large part due to limitations of existing diagnostic methods for these infections. Detection of species-specific volatile sesquiterpene metabolites of fungal origin in the breath of patients with invasive fungal infections allows the diagnosis and monitoring of these infections in vivo, non-invasively and more rapidly than possible with current diagnostic methods. While detection of exogenous microbial volatile metabolites in the breath has opened up a new and exciting dimension of diagnostic research and development in infectious diseases, we discuss the daunting challenges to volatile diagnostic biomarker discovery and clinical development.
Rapid calculations of time-harmonic nearfield pressures produced by rectangular pistons (2004)

A rapid method for calculating the nearfield pressure distribution generated by a rectangular piston is derived for time-harmonic excitations. This rapid approach improves the numerical performance relative to the impulse response with an equivalent integral expression that removes the numerical singularities caused by inverse trigonometric functions. The resulting errors are demonstrated in pressure field calculations using the time-harmonic impulse response solution for a rectangular source 5 wavelengths wide by 7.5 wavelengths high. Simulations using this source geometry show that the rapid method eliminates the singularities introduced by the impulse response. The results of pressure field computations are then evaluated in terms of relative errors and computational speeds. The results show that, when the same number of Gauss abscissas are applied to both approaches for time-harmonic pressure field calculations, the rapid method is consistently faster than the impulse response, and the rapid method consistently produces smaller maximum errors than the impulse response. For specified maximum error values of 10% and 1%, the rapid method is 2.6 times faster than the impulse response for pressure field calculations performed on a 61 by 101 point grid. The rapid approach achieves even greater reductions in the computation time for smaller errors and larger grids.
Biofuel cell based on glucose oxidase and microperoxidase-11 monolayer-functionalized electrodes (1998)

Apoglucose oxidase was reconstituted onto a pyrroloquinoline quinone and flavin adenine dinucleotide phosphate, PQQ–FAD, monolayer associated with a rough Au electrode to yield a bioelectrocatalytically active glucose oxidase, GOx. Electrically contacted PQQ–FAD/GOx monolayer was applied to the biocatalytic oxidation of glucose. A microperoxidase-11, MP-11, monolayer was assembled onto a rough Au electrode and used for the biocatalytic reduction of H2O2. Both biocatalytic electrodes, Au/PQQ–FAD/GOx and Au/MP-11, were assembled into a biofuel cell using glucose and H2O2 as the fuel substrate and the oxidizer, respectively. The biofuel cell generates an open-circuit voltage, Voc, of ca. 310 mV and a short-circuit current density, isc, of ca. 114 µA cm–2. The maximum electrical power, Pmax, extracted from the cell is 32 µW at an external optimal load of 3 kΩ. The fill factor of the biofuel cell, f = PmaxIsc–1Voc–1, is ca. 25%.
Oral Feeding Assessment Predicts Length of Hospital Stay in Late Preterm Infants (2016)

Assessment of OFS levels in LP infants at their first oral feeding can help identify infants at risk of oral feeding issues that may delay hospital discharge. For those infants, we speculate that provision of evidence-based efficacious interventions that improve OFS may shorten hospital stay and decrease hospital re-admissions.
Tyrosine Phosphorylation of Sprouty2 Enhances Its Interaction with c-Cbl and Is Crucial for Its Function (2003)

Mammalian Sprouty (Spry) proteins are now established as receptor tyrosine kinase-induced modulators of the Ras/mitogen-activated protein kinase pathway. Specifically, hSpry2 inhibits the fibroblast growth factor receptor (FGFR)-induced mitogen-activated protein kinase pathway but conversely prolongs activity of the same pathway following epidermal growth factor (EGF) stimulation, where activated EGF receptors are retained on the cell surface. In this study it is demonstrated that hSpry2 is tyrosine-phosphorylated upon stimulation by either FGFR or EGF and subsequently binds endogenous c-Cbl with high affinity. A conserved motif on hSpry2, together with phosphorylation on tyrosine 55, is required for its enhanced interaction with the SH2-like domain of c-Cbl. A hSpry2 mutant (Y55F) that did not exhibit an enhanced binding with c-Cbl failed to retain EGF receptors on the cell surface. Furthermore, individually mutating hSpry2 residues 52-59 to alanine indicated a tight correlation between their affinity for c-Cbl binding and their inhibition of ERK2 activity in the FGFR pathway. We postulate that tyrosine phosphorylation "activates" hSpry2 by enhancing its interaction with c-Cbl and that this interaction is critical for its physiological function in a signal-specific context.
Evidence for an elevated frequency of in vivo somatic cell mutations in ataxia telangiectasia. (1989)

Somatic cell mutation frequency in vivo was measured in individuals with high cancer risk who were from ataxia telangiectasia (A-T) families. The assay for somatic mutation measures the frequency of variant erythrocytes which are progeny of erythroid precursor cells with mutations that result in a loss of gene expression at the polymorphic glycophorin A (GPA) locus. Samples from 14 of 15 A-T homozygotes showed high frequencies of GPA gene expression-loss variant cells with normal expression of only one of the two alleles at the GPA locus (i.e., GPA hemizygous variant cells). The mean elevation of the frequency of hemizygous variant cells over those in normal controls and unaffected family members was 7-14-fold. A-T homozygotes also showed an increase in the frequency of cells in which one allele at the GPA locus had lost expression and in which the remaining allele was expressed at a homozygous level (i.e., GPA homozygous variant cells). Family members who are obligate A-T heterozygotes did not appear to have a significantly elevated frequency of GPA hemizygous or homozygous variant cells. These indications of elevated in vivo frequencies of variant erythrocytes in A-T homozygotes support a causal link between susceptibility to somatic mutation and susceptibility to cancer.
Recalibrated Tree of Leaf Beetles (Chrysomelidae) Indicates Independent Diversification of Angiosperms and Their Insect Herbivores (2007)

Previous calibrations proposing a much older origin of Chrysomelidae were not supported. Therefore, chrysomelid beetles likely radiated long after the origin of their host lineages and their diversification was driven by repeated radiaton on a pre-existing diverse resource, rather than ancient host associations.
Blood-Brain Barrier Abnormalities in Longstanding Multiple Sclerosis Lesions. An Immunohistochemical Study (1994)

Thirty-five randomly selected plaques from five patients with longstanding multiple sclerosis were examined immunohistochemically for evidence of extravascular serum proteins. One lesion showed histological evidence of active demyelination and 34 were inactive. In the one active lesion and in 26 of the 34 inactive lesions, serum proteins were detected outside blood vessels in a distribution consistent with leakage during life. The findings suggest that the blood-brain barrier (BBB) is permanently damaged in many old plaques, although to a degree not often detectable by current gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA)-enhanced magnetic resonance imaging (MRI). The findings also suggest that in patients with multiple sclerosis, a breached BBB is not by itself sufficient to induce active demyelination. Continuous exposure of demyelinated axons and glia to cytokines, antibody or other factors present in the circulation might be important, however, in preventing oligodendrocyte regeneration and new myelin formation in longstanding lesions.
A nucleolytic lupus autoantibody is toxic to BRCA2-deficient cancer cells (2014)

Cancer cells with defects in DNA repair are highly susceptible to DNA-damaging agents, but delivery of therapeutic agents into cell nuclei can be challenging. A subset of lupus autoantibodies is associated with nucleolytic activity, and some of these antibodies are capable of nuclear penetration. We hypothesized that such antibodies might have potential as therapeutic agents targeted towards DNA repair-deficient malignancies. We identified the lupus autoantibody 5C6 as a cell-penetrating nucleolytic antibody and found that 5C6 has a differential effect on a matched pair of BRCA2-proficient and deficient DLD1 colon cancer cells. 5C6 selectively induced γH2AX in, and suppressed the growth of, the BRCA2-deficient cells. These findings demonstrate the potential utility of 5C6 in targeted therapy for DNA repair-deficient malignancies and strengthen the rationale for studies of additional lupus autoantibodies in order to identify the best candidates for development as therapeutic agents. In addition, the toxic effect of 5C6 on BRCA2-deficient cells provides further support for the hypothesis that some lupus autoantibodies contribute to the lower risk of specific cancers associated with systemic lupus erythematosus.
Inhibition of vascular endothelial growth factor receptor 2–mediated endothelial cell activation by Axl tyrosine kinase receptor (2004)

GAS6, the product of a growth arrest specific (GAS) gene, is the ligand of the tyrosine kinase receptor Axl. GAS6 and Axl are both expressed in endothelial cells, where they are involved in many processes such as leukocyte transmigration through capillaries and neointima formation in injured vessels. Here, we show that Axl stimulation by GAS6 results in inhibition of the ligand-dependent activation of vascular endothelial growth factor (VEGF) receptor 2 and the consequent activation of an angiogenic program in vascular endothelial cells. GAS6 inhibits chemotaxis of endothelial cells stimulated by VEGF-A isoforms, but not that triggered by fibroblast growth factor-2 or hepatocyte growth factor. Furthermore, it inhibits endothelial cell morphogenesis on Matrigel and VEGF-A-dependent vascularization of chick chorion allantoid membrane. GAS6 activates the tyrosine phosphatase SHP-2 (SH2 domain-containing tyrosine phosphatase 2), which is instrumental in the negative feedback exerted by Axl on VEGF-A activities. A dominant-negative SHP-2 mutant, in which Cys 459 is substituted by Ser, reverted the effect of GAS6 on stimulation of VEGF receptor 2 and endothelial chemotaxis triggered by VEGF-A. These studies provide the first demonstration of a cross talk between Axl and VEGF receptor 2 and add new information on the regulation of VEGF-A activities during tissue vascularization.
The Blood-Brain Barrier: Its Influence in the Treatment of Brain Tumors Metastases (2012)

Brain metastases represent the most common intracranial tumors in the adults. Its incidence outnumbers that of primary brain tumors by a tenfold factor. Estimated cumulative incidence is between 10 to 20% of all cancer patients, which would represent over 170 000 new cases in the US. Typically, patients with multiple brain metastases are exposed to whole brain radiation therapy, as a palliative measure. Resulting median survival improvement is modest, ranging from 3 to 5 months. This survival has not been altered despite 3 decades of clinical research aiming at improving outcome of these patients. The role of standard chemotherapy in the treatment of brain metastases has always been marginal, as the penetration of chemotherapy beyond the BBB (blood-brain barrier) is considered limited. Whereas the BBB is universally recognized as a physiological entity, its role in the treatment of brain metastases remains controversial. Metastatic lesions often depict a homogeneous intense enhancement on either CT or MRI, thus implying that the brain tumor barrier (BTB) is breached. Although there is no doubt that the BBB and BTB suffer from variable degrees of breach in integrity in the presence of malignant brain tumors, impediment to drug delivery remains, and strategy to optimize delivery must be considered if one is to really impact patient � s outcome in the treatment of these diseases. The intended purpose of this paper is to review current data on the role of the BBB in the treatment of CNS metastatic disease.