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PubMed1991

A highly sensitive method for quantitative analysis of phospholipid molecular species by high-performance liquid chromatography.

A highly sensitive method was developed for quantitative analysis of phospholipid molecular species. Diradylglycerols prepared from phospholipids with phospholipase C were converted to the anthroyl-diradylglycerol derivatives, which could be separated into molecular species and sensitively quantified by reverse-phase HPLC using a fluorescence detector. All the molecular species of the derivatives had the same peak area per mole, and the peak areas were proportional to the amounts of the derivatives. Quantification could be carried out at the femtomole level.

Chromatography, High Pressure Liquid↗

PubMedDate not supplied

Quantitative analysis of seizure frequency 1 week and 6, 12, and 24 months after surgery of epilepsy.

We made quantitative analysis of seizure frequency 1 week and 6, 12, and 24 months after seizure surgery. Seizure recurrence was significantly higher when seizures occurred in the first postoperative week. Seizure recurrence increased progressively with longer follow-ups, but the 6 month postoperative follow-up period was an excellent index of long-term outcome. In operative follow-up studies, seizure frequency should be reported at fixed follow-up periods, e.g., at 6 months and 1, 2, 5, and 10 years. Meaningful comparison of outcomes between different studies is possible only when reports include outcome at fixed postoperative follow-up periods (as opposed to ranges of follow-up periods).

Chi-Square Distribution↗

PubMed2003

Bell palsy: quantitative analysis of MR imaging data as a method of predicting outcome.

PURPOSE: To assess the prognostic value of quantitative analyses of region-of-interest (ROI) magnetic resonance (MR) imaging data in patients with acute facial nerve palsy. MATERIALS AND METHODS: In a single-blinded study, MR images were obtained in 39 patients (32 men and seven women; age range, 18-75 years; average age, 37.9 years) with acute facial nerve palsy. MR images were obtained before the 6th day of illness, on the first day of standard inpatient treatment with high-dose steroids. Signal intensity (SI) was measured at ROIs in each of five segments (internal auditory canal [IAC]; geniculate ganglion; and labyrinth, tympanic, and mastoid segments) of the intratemporal portion of the facial nerve and quantitatively analyzed. The SI measurements in the five segments were summed and divided by 100 to provide a basis for establishing an MR imaging index. SI increases and MR imaging indexes were compared with available clinical findings and electrophysiologic data. RESULTS: Data for all 39 patients could be analyzed. The MR imaging index was significantly higher in patients with poor outcomes than in patients with favorable outcomes (specificity, 97%; sensitivity, 75%; P <.01). The SI increases in the IAC were significantly different between patients who progressed to full recovery (mean increase, 45.7%) and patients who developed chronic facial paralysis (mean increase, 156.5%) (sensitivity, 100%; specificity, 97%; P <.001). The results of differentiating between patients with good and those with poor outcomes on the basis of SI measurements in the IAC were found to be in complete agreement with electrophysiologic data. CONCLUSION: Quantitative analysis of ROI MR imaging data is a valid method of predicting the outcome of acute facial nerve palsy during the first days after onset of symptoms and thus at a time when it is not yet possible to obtain valuable prognostic information by using electrophysiologic methods.

Action Potentials↗

PubMedDate not supplied

Quantitative analysis of synovial fibrosis in the infrapatellar fat pad before and after anterior cruciate ligament reconstruction.

We performed quantitative analysis of synovial fibrosis in the infrapatellar fat pad in 26 patients who underwent arthroscopically assisted anterior cruciate ligament reconstructions. Twelve patients underwent reconstruction with patellar tendon autografts, and 14 had reconstructions with semitendinosus and gracilis tendon autografts. Synovial samples were obtained at the time of reconstruction from 10 patients and at second-look arthroscopy from all 26 patients. Sections from quick-frozen samples were stained with either hematoxylin and eosin or Fast green and Sirius red. We used sodium hydroxide in absolute methanol to elute the Fast green and Sirius red stains, and the total collagen content of each section was estimated by measuring the optical density of the eluted solution. The volume of each section was determined on a computer using an imaging program, and collagen content per unit of tissue was calculated. Median collagen content was 15.3 micrograms/mm3 for the preoperative samples, 25.1 micrograms/mm3 for the group with patellar tendon autografts, and 27.1 micrograms/mm3 for the group with hamstring tendons autografts. Analysis of preoperative and postoperative paired samples revealed a significant increase in synovial collagen after anterior cruciate ligament reconstruction. We observed increased fibrosis in patients who had pain on exertion or stiffness in squatting after the reconstructive surgery.

Adipose Tissue↗

PubMed1999

Quantitative analysis of neuronal nitric oxide synthase-immunoreactive neurons in the mouse hippocampus with optical disector.

A detailed quantitative analysis of immunocytochemically identified nonprincipal neurons containing neuronal nitric oxide synthase (nNOS) was performed on the mouse hippocampus, with particular reference to the dorsoventral gradient. The present study applied two variations of a stereologic technique, the optical disector--one that used confocal laser-scanning microscope optical sections to examine colocalization of nNOS and glutamic acid decarboxylase 67 (GAD67), and the other that used conventional thick sections to examine numerical densities (NDs) and cell sizes of nNOS-immunoreactive (IR) neurons. Colocalization analysis indicated that practically all nNOS-IR neurons (97.6%) were GAD67-IR, whereas a part of the GAD67-IR neurons (about 30%) were nNOS-IR in the whole hippocampus at both dorsal and ventral levels. The percentages of GAD67-IR neurons containing nNOS were higher in the dentate gyrus (DG, about 50%), and lower in the Ammon's horn (about 20%). Laminar analysis revealed that the majority of GAD67-IR neurons contained nNOS in the stratum lacunosum-moleculare of the CA3 region (about 60%) and in the molecular layer of the DG (about 80%). The NDs of nNOS-IR neurons in the whole hippocampus showed a dorsoventral gradient, which increased from dorsal (1.6 x 10(3)/mm3) to ventral (2.2 x 10(3)/mm3) levels. The NDs were relatively higher in the principal cell layers, where about 40% of nNOS-IR neurons were situated both in the Ammon's horn and DG. The mean cell sizes of nNOS-IR neurons showed no remarkable laminar differences or dorsoventral gradient in the Ammon's horn, but they were extensively larger in the hilus of the DG than in other layers. These results indicate that nNOS-IR neurons in the mouse hippocampus represent a subpopulation of gamma-aminobutyric acid (GABA)ergic neurons and suggest that the laminar distributions of nNOS-IR neurons related to possible functional heterogeneity of GABAergic neurons in each hippocampal layer.

Animals↗

PubMed2004

[A novel calibration technique for quantitative analysis of FTIR spectra].

Fourier transform infrared spectroscopy (FTIR) can be used for the continuously on-line quantitative determination of the concentrations of several gas components in smoke gas. The process of acquiring accurate calibration of spectra is one of the most important steps in the quantitative analysis. In the present paper, a novel calibration technique was proposed and evaluated by the results of CO and HCl. Data obtained by this new technique were compared to those of conventional concentration-based calibration. The results showed that this calibration technique is feasible, and its reliability and validity were also confirmed. Further more, it has several other advantages, which will also be discussed here. Finally, the calibration problem that the substances are liquid at ambient temperature was solved by this technique.

Algorithms↗

PubMed2005

[Quantitative analysis of factors affected mortality trend in Chinese, 2002].

OBJECTIVE: To explain trend of death in Chinese by quantitative analysis of demographic and non-demographic factors and estimate the proportion of contribution of non-demographic and demographic factors. METHODS: Using census data and death causes data of National Disease Surveillance Points at 1991 and 2000 to calculate the proportion of contribution of demographic and non-demographic factors and to change on various death causes from 1991 to 2000 by methods of decomposing the differences of death rates. RESULTS: The death rate showed a rapid decrease during 1950 - 1975, mainly owing to the contribution of non-demographic factors, including economic development, popularization of education and health service, especially the "patriotic hygiene movement". During 1991 - 2000, the death causes of lung cancer, liver cancer, breast cancer, chronic heart disease, stroke, diabetes and traffic accident had been increasing. The increase of deaths caused by these diseases were contributed to the non-demographic factors including 63% of the increase on lung cancer and 88% of increase on death rate of traffic accidents. CONCLUSION: The study showed that the risk factors had contributed to the increase of death rates, including behavioral risk factors described in the preceding 5 papers as smoking and passive smoking, unhealthy diet, sedentary life style, violating traffic regulation etc. In order to reduce the death rates on cancer, heart diseases, diabetes, traffic accidents, emphasis should be also laid on the change of unhealthy behaviors.

Cause of Death↗

PubMed1987

[Diagnosis of variants of neuropathies using the standardized methodology of quantitative analysis of the interference EMG].

In examining 36 patients with neuropathies the authors used standardized leads and a quantitative analysis of the interferential EMG and established the criteria for the differential diagnosis of radiculopathies, neuropathies in particular. Comparison with the findings of analysis of potentials of motor units showed that a "myopathic" shift revealed in some patients was due to stage characteristics of denervation and re-innervation process.

Adult↗

PubMed1980

[Quantitative analysis of the relationship between arterialization of blood and irregularities of ventilation--perfusion ratios].

Comparative data on the quantitative analysis of the relationship between arterialization and irregularity of the ventilation perfusion ratios are presented for a simple two-component lung model and for a model with a logarithmically normal distribution of VA/Q. A possibility of respiratory failure existence without material shifts in the arterial blood gas composition is substantiated.

Humans↗

PubMed1995

Quantitative analysis of (l)-ephedrine and (d)-pseudoephedrine in plasma by high-performance liquid chromatography with fluorescence detection.

Quantitative analysis of (l)-ephedrine (l-Ep) and (d)-pseudoephedrine (d-Ps) in plasma by high-performance liquid chromatography (HPLC) is described. The newly developed method is based on a precolumn derivatization with 5-dimethyl-aminonaphthalene-1-sulfonyl chloride (DNSC1) in acetonitrile. The diastereomers formed were separated on a reversed phase column by HPLC with fluorescence detection employing 0.6% phosphate buffer (pH 6.5)-methanol (3:8, v/v) as mobile phase. The detection limit of each Ephedra alkaloid stereoisomer was 0.5 ng at a signal-to-noise ratio of 3:1, the linear response to each stereoisomer being 1-800 ng.ml-1. The plasma level profile of l-Ep and d-Ps in guinea pig was investigated by this method. The determination of l-Ep and d-Ps in plasma of a volunteer after oral administration of Xiao Qinglong Heji was also performed.

Animals↗

PubMed1995

High-density cDNA filter analysis: a novel approach for large-scale, quantitative analysis of gene expression.

In order to analyze the expression profiles of a large number of genes in the tissues (or cells) of interest, and to identify the genes preferentially expressed in the tissues, we have developed a large-scale gene expression analysis system. It is based on the hybridization of the mRNAs from the tissues with a high-density cDNA filter followed by the quantitative measurement of the amount of the hybridized mRNA on each cDNA spot. By employing a high-performance bioimaging analyzer, the system allowed us to compare the expression profiles of thousands of genes (cDNAs) simultaneously with a sensitivity comparable to conventional Northern blotting analysis. By this system (called high-density cDNA filter analysis or HDCFA), the expression profiles of 2505 cloned human brain cDNAs (genes) were monitored. Through the comparison of the expression profiles of these cDNAs in the adult brain, fetal brain and adult liver, about one half of these brain cDNAs (1239 clones) were identified as the candidates which were expressed preferentially in the brain. Among these, 408 and 288 clones were found to be preferentially expressed in the adult and fetal brain, respectively. The results have shown that the system may be widely applicable for analysis of the gene expression profiles of various tissues on a large scale.

Base Sequence↗

PubMed1994

Quantitative analysis of 2-oxoglutarate in biological samples using liquid chromatography with electrochemical detection.

This paper describes a technique for quantitative analysis of 2-oxoglutarate (alpha-ketoglutarate) in biological samples using liquid chromatography with electrochemical detection (LC-EC). This method utilizes a simplified, efficient sample preparation designed to select for 2-oxoglutarate and similar compounds by derivatization with phenylhydrazine. The response was linear over the range from 62.5 to 1000 ng/ml. The least quantifiable concentration was 62.5 ng/ml and the least detectable concentration was 25 ng/ml. To test the ability of the assay to measure 2-oxoglutarate in biological samples, this method was used to quantitate the 2-oxoglutarate content in chick osteoblast cultures and to determine the ability of the assay to accurately measure a standard addition of 500 ng/ml 2-oxoglutarate when added to a sample of the forementioned groups. The 2-oxoglutarate content of these cells was 6.67 +/- 1.20 ng/micrograms DNA or 105 +/- 18 ng/cell layer (mean +/- 95% confidence interval) and the assay accurately measured the standard addition. This method was also used to quantitate 2-oxoglutarate content in whole embryonic chick calvariae containing 6.40 +/- 0.95 ng/mg dry bone weight or 37.5 +/- 5.5 ng/bone. This assay provides significantly lower detection limits than the currently available procedures and is suitable for determination of 2-oxoglutarate in biological samples where very low amounts of 2-oxoglutarate are found. This method is the first application of LC-EC for quantitating 2-oxoglutarate.

Animals↗

PubMed2003

Quantitative analysis of testicular interstitial fibrosis after vasectomy in humans.

PURPOSE: Germ cell differentiation, DNA synthesis, and apoptosis can be evaluated quantitatively. On the other hand, an interstitial lesion is difficult to examine. We have focused on the quantitative analysis of testicular interstitial fibrosis after vasectomy. MATERIALS AND METHODS: Forty testicular biopsy specimens from twenty consecutive men were obtained at vasovasostomy. Johnsen's mean score was calculated from testicular biopsy specimens. Percent of interstitial fibrosis was determined quantitatively by the NIH-Image after Masson-trichrome staining. RESULTS: A significant increase in interstitial fibrosis was observed along with the obstructive interval (p < 0.001). Johnsen's mean score count did not associate with the obstructive interval. CONCLUSION: Interstitial lesions of testicular physiology and pathophysiology can be evaluated using the NIH-Image. Interstitial fibrosis, but not the intraseminiferous status, reflects the irreversible damage of vasectomized testes.

Adult↗

PubMed2003

Quantitative analysis of sponsorship bias in economic studies of antidepressants.

BACKGROUND: Concern is widespread about potential sponsorship influence on research, especially in pharmacoeconomic studies. Quantitative analysis of possible bias in such studies is limited. AIMS: To determine whether there is an association between sponsorship and quantitative outcomes in pharmacoeconomic studies of antidepressants. METHOD: Using all identifiable articles with original comparative quantitative cost or cost-effectiveness outcomes for antidepressants, we performed contingency table analyses of study sponsorship and design v. study outcome. RESULTS: Studies sponsored by selective serotonin reuptake inhibitor (SSRI) manufacturers favoured SSRIs over tricyclic antidepressants more than non-industry-sponsored studies. Studies sponsored by manufacturers of newer antidepressants favoured these drugs more than did non-industry-sponsored studies. Among industry-sponsored studies, modelling studies favoured the sponsor's drug more than did administrative studies. Industry-sponsored modelling studies were more favourable to industry than were non-industry-sponsored ones. CONCLUSIONS: Pharmacoeconomic studies of antidepressants reveal clear associations of study sponsorship with quantitative outcome.

Antidepressive Agents↗

PubMed2005

Intact-protein-based high-resolution three-dimensional quantitative analysis system for proteome profiling of biological fluids.

The substantial complexity and vast dynamic range of protein abundance in biological fluids, notably serum and plasma, present a formidable challenge for comprehensive protein analysis. Integration of multiple technologies is required to achieve high-resolution and high-sensitivity proteomics analysis of biological fluids. We have implemented an orthogonal three-dimensional intact-protein analysis system (IPAS), coupled with protein tagging and immunodepletion of abundant proteins, to quantitatively profile the human plasma proteome. Following immunodepletion, plasma proteins in each of paired samples are concentrated and labeled with a different Cy dye, before mixing. Proteins are subsequently separated in three dimensions according to their charge, hydrophobicity, and molecular mass. Differences in the abundance of resolved proteins are determined based on Cy dye ratios. We have applied this strategy to profile the plasma proteome for changes that occur with acute graft-versus-host disease (GVHD), following allogeneic bone marrow transplantation (BMT). Using capillary HPLC ESI Q-TOF MS, we identified 75 proteins in the micromolar to femtomolar range that exhibited quantitative differences between the pre- and post-GVHD samples. These proteins included serum amyloid A, apolipoproteins A-I/A-IV, and complement C3 that are well-known acute-phase reactants likely reflecting the post-BMT inflammatory state. In addition, we identified some potentially interesting immunologically relevant molecules including vitamin D-binding protein, fetuin, vitronectin, proline-rich protein 3 and 4, integrin-alpha, and leukocyte antigen CD97. IPAS provides a combination of comprehensive profiling and quantitative analysis, with a substantial dynamic range, for disease-related applications.

Adult↗

PubMed2004

Appropriate utilization of semi-quantitative analysis in salivary scintigraphy.

AIM: The purpose of this case-control study was to determine whether semi-quantitative indices derived from salivary time-activity curves (TACs) are useful in the diagnosis and management of xerostomia. METHODS: Twenty-six healthy volunteers and 83 consecutive patients with xerostomia, including a subset of 40 patients with Sjogren's syndrome, underwent sequential salivary scintigraphy (SSS). Semi-quantitative analysis of the TACs was performed, deriving six different indices, previously cited in the literature, for each patient. These reflected trapping and uptake, stimulated excretion, or stimulated and unstimulated oral radioactivity. The indices were the percentage uptake, uptake ratios, maximum accumulation, pre-stimulatory oral radioactivity index, post-stimulatory oral radioactivity index and ejection fraction. RESULTS: Reduced parotid activity relative to submandibular activity, expressed as the P : S ratio, was able to distinguish abnormal from normal salivary function, and a parotid ejection fraction of greater than 50% also indicated normal parotid function. The other parameters showed no statistically significant difference between controls and patients. Individual variation in all indices served to widen the reference limits obtained from controls to the extent that they overlapped with those from the xerostomic population. CONCLUSIONS: This finding, together with previous work indicating that uptake parameters are only sensitive to differences exceeding 25% of the gland mass, the possibility that xerostomia may result from qualitative as well as quantitative changes in saliva and the probability that immune factors decrease neurosecretory circuits without affecting acinar mass, suggest that those indices derived from salivary TACs that directly reflect trapping and uptake are not useful in the detection of salivary gland disease.

Case-Control Studies↗

PubMed1993

Usefulness of repeat coronary angiography 24 hours after successful balloon angioplasty to evaluate early luminal deterioration and facilitate quantitative analysis.

Because of the unavoidable occurrence of vessel disruption after successful coronary balloon angioplasty, the reliability of quantitative angiographic analysis in that setting has been questioned. For this reason and the suggested occurrence of delayed elastic recoil, repeat angiography at 24 hours has been advocated in clinical interventional trials. In this study, these issues are confronted by performing comprehensive quantitative analysis (Cardiovascular Angiographic Analysis System) of coronary angiograms, acquired in multiple identical projections immediately after and 24 hours after angioplasty, in 102 patients with 110 successfully dilated lesions. Vasomotion was controlled by intracoronary nitrate before angiography and all patients were fully anticoagulated (activated partial thromboplastin time 85 to 120 seconds) for > 24 hours. Paired Student's t tests applied to angiographic measurements revealed that there was no significant deterioration in minimal luminal diameter or cross-sectional area from immediately after angioplasty to 24 hours later. It can thus be inferred that there is no phenomenon of delayed elastic recoil, at least during this time period. Measurement accuracy and precision of the Cardiovascular Angiographic Analysis System from the postangioplasty angiogram are highly acceptable, at < 0.01 and +/- 0.20 mm, respectively. Therefore, it is concluded that routine repeat 24-hour angiography is not indicated after successful angioplasty. A highly significant increase (p < 0.001) in reference diameter (+0.11 +/- 0.18 mm) was responsible for the apparent increase in percent diameter stenosis (2.4 +/- 7%), a finding that demonstrates the potential for error by selective application of percent diameter stenosis measurements alone. Preferential use of absolute luminal measurements is thus strongly recommended for clinical trials with angiographic monitoring.

Adult↗

PubMed2004

Chemical probes and tandem mass spectrometry: a strategy for the quantitative analysis of proteomes and subproteomes.

Quantitative proteome profiling using mass spectrometry and stable isotope dilution is being widely applied for the functional analysis of biological systems and for the detection of clinical, diagnostic or prognostic marker proteins. Because of the enormous complexity of proteomes, their comprehensive analysis is unlikely to be routinely achieved in the near future. However, in recent years, significant progress has been achieved focusing quantitative proteomic analyses on specific protein classes or subproteomes that are rich in biologically or clinically important information. Such projects typically combine the use of chemical probes that are specific for a targeted group of proteins and may contain stable isotope signatures for accurate quantification with automated tandem mass spectrometry and bioinformatics tools for data analysis. In this review, we summarize technical and conceptual advances in quantitative subproteome profiling based on tandem mass spectrometry and chemical probes.

Amino Acids↗