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At least 55 records · Page 3Linked to original sources
PubMed1979

Electroencephalographic quantification by time domain analysis in normal 7--15-year-old children.

Automatic EEG analysis was performed on 239 apparently healthy school age children. The children were classed in 3 age groups: (1) average age of 7; (2) average age of 11; (3) average age of 15. A time analysis method, comparable to classical visual analysis, permitted quantification of the records. The mean amplitude, frequency and percentage time for alpha and theta rhythms were determined for each subject for fronto-central and centro-occipital derivations bilaterally. Records were performed during periods of rest with eyes open and eyes closed. During hyperventilation, records were taken with eyes closed. The normal ranges of parameters were determined by calculating their means and standard deviations, for each age group under each recording condition. Delta and beta rhythm values were not calculated, because of their rarity in this apparently normal sample. The precision obtained by automatic analysis could not have been obtained by means of classical visual analysis. The present findings suggest that the statistical analysis of well-defined groups of normal and pathological children could be of significant value.

Adolescent↗
PubMed1979

Microprocessor-based EEG spike detection and quantification.

A microprocessor-based system for the detection and quantification of sharp EEG waveforms is described. The hierarchical approach utilises initial transient detection based on computation of a second-derivative measure of curvature, followed by pattern-recognition and artifact-rejection routines based on consideration of specific waveform parameters. Initials results demonstrate an ability to approximate human-analysis results, while providing precise measures of amplitude, duration, and sharpness. The decreasing cost of microprocessors makes multichannel configurations economically feasible.

Analog-Digital Conversion↗
PubMed2026

Protocol to improve isoform-level quantification of low-abundance transcripts via STALARD pre-amplification.

STALARD (selective target amplification for low-abundance RNA detection) enables isoform-level quantification of low-abundance RNAs using conventional laboratory equipment. Here, we describe steps for RNA isolation, primer design, reverse transcription, selective target amplification, and downstream analysis. The protocol couples selective pre-amplification with a quantitative reverse-transcription PCR (RT-qPCR) readout and optional nanopore sequencing. Using 1 μg input RNA and 12 pre-amplification cycles, STALARD reduces Cq values by approximately 10-12 cycles, bringing the target into a reliably quantifiable range. For complete details on the use and execution of this protocol, please refer to Jeong et al.1.

Gene Expression↗
PubMed1979

Methylation analysis in glycoprotein chemistry. General procedure for quantification of the products of solvolysis of permethylated glycopeptides and glycoproteins.

A technique for the gas chromatographic analysis of the products of solvolysis of permethylated glycopeptides and glycoproteins has been developed. It involves methanolysis of a permethylated compound, quantitative transformation of methyl ethers of methyl glycosides into the corresponding O-trimethylsilyl(TMS)-O-methylalditols [2-deoxy-2-(N-methyl)acetamido-O-TMS-O-methylalditols in the case of hexosamine derivatives] and gas chromatographic quantification using a single column packed with 0.4% OV-225 on surface-modified Chromosorb.

Acetylglucosamine↗
PubMed1977

New gas chromatogrphic assay for the quantification of methadone. Application in human and animal studies.

A new gas chromatographic assay utilizing 2-dimethylamino-4,4-diphenyl-5-nonanone as the internal standard was developed for the quantification of methadone. The method involved extraction of methadone with 1-chlorobutane from tissue at pH 9.8, re-extraction of an aliquot of the organic solvent with 0.5 M sulphuric acid, alkalinization and final extraction into chloroform. The assay was used to determine the concentration of methadone (i) in whole blood samples from a normal volunteer following a single 9.4-mg oral dose of d-methadone hydrochloride, (ii) in whole blood, saliva and gastric juice from a methadone addict maintained on 90 mg of dimethadone hydrochloride per day, (iii) in mouse liver microsomes incubated with methadone, and (iv) in the perfusate of the isolated perfused rat liver.

Animals↗
PubMed2026

Development of a High-Sensitivity Glycoproteomics Approach for Fc-Specific Quantification of IgG Core Fucosylation in Traumatic Brain Injury.

Traumatic brain injury (TBI) triggers complex neuroinflammatory cascades that involve sustained immune activation and dysregulated antibody effector functions. Immunoglobulin G (IgG) Fc N-glycosylation, particularly core fucosylation, critically modulates immune signaling through altered Fcγ receptor (FcγR) interactions; however, its role in TBI remains unexplored. Here, we developed a high-sensitivity, mass spectrometry-based glycoproteomics method for the systematic analysis of IgG Fc core fucosylation dynamics following TBI. The approach integrates Fc-specific enzymatic truncation with GlycINATOR (EndoS2) and tryptic digestion, followed by high-resolution LC-MS/MS profiling, enabling confident identification of truncated Fc glycopeptides. Furthermore, a targeted parallel reaction monitoring (PRM) strategy allowed direct quantification of core fucosylated and afucosylated glycopeptides from 10 μg of crude serum protein, eliminating the need for IgG purification. Our results reveal time-dependent and subclass-specific remodeling of IgG Fc fucosylation postinjury, characterized by an overall reduction in fucosylated species and a relative increase in afucosylation. Collectively, this study establishes a scalable analytical platform for Fc-specific glycosylation profiling and identifies IgG core fucosylation as a candidate molecular indicator of immune dysregulation in TBI, providing new insights into post-traumatic immune regulation.

Brain Injuries, Traumatic↗
PubMed2026

Chimeric structural isomer fragments as cost-efficient internal standards for amino acid quantification by mass spectrometry.

Amino acid (AA) profiles from body fluids such as blood and urine are clinical indicators for diagnosing metabolic and hepatic diseases. Current quantitative methods, such as liquid chromatography-mass spectrometry (LC-MS) with isotopically labelled internal standards (ISs), are costly and technically demanding. This study proposes a cost-efficient alternative using structural isomers as ISs in a direct liquid infusion (DLI) tandem mass spectrometry (MS/MS) approach. The method leverages chimeric spectra and fragment intensity ratios to quantify AAs, demonstrating high linearity and precision even with a 3D ion trap mass analyser. This approach offers a viable strategy for AA quantification in preventive medicine, particularly for screening metabolic diseases such as phenylketonuria, diabetes, and liver dysfunction.

Amino Acids↗
PubMed2025

FootprintCharter: unsupervised detection and quantification of footprints in single molecule footprinting data.

SUMMARY: Single molecule footprinting profiles the heterogeneity of TF occupancy at cis-regulatory elements across cell populations at unprecedented resolution. The single molecule nature of the data in principle allows for observing the footprint of individual transcription factors and nucleosomes. However, we currently lack algorithms to quantify these occupancy patterns of chromatin binding factors in an automated way and without prior assumptions on their genomic location. Here we present FootprintCharter, an unsupervised tool to detect and quantify footprints for transcription factors (TFs) and nucleosomes from single molecule footprinting data. After detection, TF footprints can be labeled with orthogonal motif annotations provided by the user. FootprintCharter allows for the quantification of complex molecular states such as positioning of unphased nucleosomes and combinatorial co-binding of multiple TFs. AVAILABILITY AND IMPLEMENTATION: FootprintCharter is freely available on Bioconductor with version 2.2.0 of https://bioconductor.org/packages/SingleMoleculeFootprinting through the functions FootprintCharter, PlotFootprints, and Plot_FootprintCharter_SM.

Transcription Factors↗
PubMed1975

Analysis and quantification of ether lipids by chromatographic methods.

Chromatographic methods, especially thin-layer chromatography (TLC) and gas-liquid chromatography (GLC) are widely used in investigations of the occurrence, molecular structure and metabolism of ether lipids. The application of such techniques to structural analysis and quantification, in combination with methods for the degradation and derivatization of ether lipids, is discussed.

Alkenes↗
PubMed2026

ClearDepthIAS enables automated high-throughput quantification of roots in soil-grown taproot crops.

Understanding root system architecture is critical for improving crop productivity and resilience, yet phenotyping root traits such as root growth angle and rooting depth remains technically challenging, especially at high throughput. Here, we present ClearDepthIAS, a high-throughput imaging and analysis platform that enables nondestructive, automated quantification of root architecture traits in taproot system crops. By capturing and stitching 360° images of roots growing along the transparent walls of pots and applying deep learning-based segmentation (ClearDepth-WRT), we measured wall root shallowness (WRS)-a proxy for root growth angle-with high precision. We demonstrated for the tap root systems of soybean and canola that the system accurately detects root tips, quantifies their vertical distribution, and extracts biologically meaningful traits such as root area, distribution indices, and growth angles. Validation experiments in canola and soybean demonstrated that WRS can correlate with root crown architecture in mature plants, both in greenhouse and field settings. Furthermore, WRS and root distribution indices derived from ClearDepthIAS are predictors of early root architecture and can be correlated with root biomass distribution across soil depths under field conditions; however, environmental interactions may influence these relationships and weaken or even negate such correlations, as observed when comparing field to field variation in root system architecture. Our system enables efficient phenotyping of genetically diverse populations, with medium to high trait heritability, supporting its utility for genome-wide association studies and breeding. ClearDepthIAS accelerates the development of root ideotypes for improved resource acquisition and carbon sequestration, offering a scalable tool for supporting climate-resilient agriculture.

Plant Roots↗
PubMed1979

Quantification of joint laxity.

We have compared the finger hyperextensometer (Jobbins et al., 1978) and the scoring system of Carter and Wilkinson (1964), modified by Beighton et al. (1973), in the quantification of joint laxity in a population selected to demonstrate a wide range of joint movement. Both systems correlated well (P less than 0.001) with a 'global index' of joint laxity derived by adding the arcs of movement recorded at most joints in the body by the method of the American Academy of Orthopaedic Surgeons (1965). The Carter and Wilkinson system produced better correlations and is the method of choice for assessing generalized joint laxity.

Humans↗
PubMed1979

Quantification of the human orienting response to another human: lesioned and psychiatric patients compared to normals.

A method for eliciting, controlling, and quantifying the alpha suppression response to a human "real-person" stimulus is presented. Improved control is achieved by a feedback from the EEG response to the presentation of the stimulus. Quantification is comprehensive in that initial response and subsequent habituation for both latency and duration are described. Patients who had suffered a focal lesion but who had recovered sufficiently to travel from one hospital to another by taxi were compared with hospitalized psychiatric patients and normal volunteers. Lesioned patients showed less EEG response to visual stimuli than did the other groups, even with an evocative, real-person stimulus. The differences among the three groups were most evident at the onset of stimulation and less so after habituation had occurred.

Adult↗
PubMed1978

Activation of the alternative pathway of complement by grain. I. C3PA conversion and quantification of complement consumption by rye.

Ground whole rye and airborne rye dust of comparable size distribution were tested for their ability to activate the complement cascade via the alternative pathway. Precipitin-negative pooled normal human serum was incubated with increasing amounts of the two rye dusts. Electrophoresis of the resultant supernatant fluids demonstrated the conversion of the proactivator of the third component of complement to the gamma-migrating activator of the third component. This activation was completely prevented by pre-treating the serum with the chelator EDTA, while pre-treatment with EGTA allowed suboptimal arc conversion, strongly implying that complement was activated via the alternative pathway. Quantification of the supernanant fluids showed dose-dependent complement consumption as defined by both CH100 immunodiffusion and CH50 tube haemolytic techniques. Airborne rye dust showed a greater quantitative potential than ground whole rye for activating the alternative pathway. These results indicate the possibility of the direct action of airborne organic dusts on the induction of inflammatory sequelae in the lungs of both sensitized and unsensitized individuals.

Air Pollutants↗
PubMed1978

Quantification and properties of tubulin polymerization in crude brain extracts and preparations of microtubular and purified tubulin.

Removal of assembled tubulin by centrifugation, followed by measurement in the supernatant of the residual colchicine binding capacity of the non-polymerized, non-precipitable tubulin, is a sensitive and reliable method of measuring tubulin polymerization. This method can be used in both crude and purified preparations of brain tubulin and allows the molar quantification of the total, polymerized and non-polymerized tubulin species in each sample. Only 40--50% of the total tubulin present in crude adult brain extracts is capable of polymerizing when incubated with GTP. The percentage of tubulin polymerizing with GTP is slightly higher in crude foetal brain extracts than in the adult. Incubation of first polymerization supernatants, containing exclusively the GTP-insensitive tubulin, with guanosine 5'-[alpha, beta-methylene]triphosphate (GuoP[CH2]PP) but not with 2.4 M glycerol results in tubulin polymerization. High concentrations of glycerol (2.4 M) promote the polymerization of tubulin in adult but not in crude foetal brain extracts. Both ATP and adenosine 5'-[alpha, beta-methylene]triphosphate (AdoP[CH2]PP) are effective in promoting the polymerization of GDP-free (90%) microtubular protein. The microtubular protein assembled with GuoP[CH2]PP or AdoP[CH2]PP has the unique character of being resistant to calcium concentrations (2mM), which cause complete depolymerization of the tubulin assembled with GTP or ATP. Phosphocellulose-purified tubulin significantly assembles when incubated with GuoP[CH2]PP or AdoP[CH2]PP at protein concentrations at which GTP or ATP do not promote polymerization. 2 micrometer tubulin is the minimal concentration required for polymerization in both crude and purified preparations of adult rat brain tubulin.

Animals↗
PubMed1979

Quantification of tetanus antitoxin in human sera. I. Counter-immunoelectrophoresis.

An extensive sero-epidemiological survey of immunity to tetanus is to be performed in Norway during 1978 and 1979 and thus a simple and reliable method for screening sera for content of tetanus antitoxin is needed. An improved counter-immunoelectrophoretic method for quantification of tetanus antitoxin is described. The toxin neutralization test in mice is considered to correlate well with protection in humans. Counter-immunoelectrophoresis has the advantage of using tetanus toxoid instead of toxin as well as being more rapid and less expensive. Specific antibodies of the IgG, IgM, and IgA classes could be read simultaneously for many sera. This may be of importance, since it is reported in the literature that only antibody of the IgG class is capable of neutralizing tetanus toxin in mice. Counter-immunoelectrophoresis is limited by being less sensitive than the toxin neutralization test in mice.

Chromatography, Gel↗
PubMed1975

Quantification of mouse macrophage chemotaxis in vitro: role of C5 for the production of chemotactic activity.

Delineation of the mechanisms of macrophage accumulation at local tissue sites will further our understanding of immunologically mediated host resistance to infectious and neoplastic diseases. Since mice are frequently used for the study of immune function, we developed a method for the quantification of mouse macrophage chemotaxis in vitro. By this method it was found that the fifth component of complement is necessary for the production of chemotactic activity in mouse serum by inflammatory agents such as endotoxin or aggregated gamma globulin. The majority of macrophage chemotactic activity produced by these agents in mouse serum can be attributed to a low-molecular-weight (ca. 15,000) chemotactic factor. The data suggest that this factor is the biologically active cleavage product of the fifth component of complement, C5a.

Animals↗
PubMed1978

Quantification of obstetric traction.

Measurements of factors involved in the degree of traction exerted during obstetric cases were carried out. Bovine material force was approximately 150 lbs. Maximum manual effort would be approximately four times this and mechanical traction would be at least 50 per cent higher again. A workable maternal fetal ratio was established for use in cases of fetal oversize. Possible quantification of other factors is also discussed.

Animals↗
PubMed1976

Low cost intrathyroidal iodine quantification with a fluorescent scanner.

A thyroid fluorescent scanner has proven to be useful for imaging thyroids in cases where isotope scans are contraindicated. Minor modifications of a commercially available scanner make possible total intrathyroidal quantification, which aids in the differentiation between primary and secondary hypothyroidism and in the diagnosis of thyroiditis.

Costs and Cost Analysis↗