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At least 721 records · Page 40Linked to original sources
PubMed1994

Quantitative analysis of chromosome in situ hybridization signal in paraffin-embedded tissue sections.

Interphase cytogenetic analysis using chromosome-specific probes is increasingly being used to detect chromosomal aberrations on paraffin-embedded tissue sections. However, quantitative analysis of the hybridization signal is confounded by the nuclear slicing that occurs during sectioning. To determine the sensitivity and accuracy of chromosome in situ hybridization for detecting numerical chromosomal aberrations on paraffin-embedded sections, in situ hybridization was performed on sections derived from mixtures of cell populations with known frequencies of numerical chromosomal aberrations and the Chromosome Index (CI) was calculated (i.e., total number of signal spots/number of nuclei counted) as a quantitative measure of chromosome copy number. The presence of 25% or more monosomic or tetrasomic cells in a given population was easily detected as a change in CI (P < 0.05). Lower degrees of polysomy could be detected as a small percentage of nuclear fragments with > 2 signal spots. The CI was not significantly influenced by a change in section thickness from 4 to 8 microM, by an increase in cell size from 478 to 986 microM3, or by the choice of detection method (fluorescence vs. conventional bright-field microscopy). Comparative analysis of touch preparations and tissue sections from the corresponding breast tumors showed that CI accurately reflects the average copy number of chromosomes in intact nuclei and may actually be superior to in situ hybridization on whole nuclei for the detection of numerical chromosomal changes in defined histologic areas. This method is thus a sensitive and accurate means of studying genetic changes in premalignant and malignant tissue, and of assessing the genetic changes associated with specific phenotypes.

Aneuploidy↗
PubMed2001

Quantitative analysis by flow cytometry of abscisic acid-inducible gene expression in transiently transformed rice protoplasts.

BACKGROUND: Quantifying plant gene expression by flow cytometry (FCM) would allow multidimensional cell-parameter analysis on a per-cell basis, thereby providing insight into the cellular mechanisms of plant gene regulation. Here we sought to establish quantitation by FCM of plant hormone (abscisic acid, ABA)-inducible green fluorescent protein (GFP) expression and to compare the method directly with traditional reporter enzyme assays. MATERIALS AND METHODS: GFP, beta-glucuronidase, and luciferase reporter genes driven by ABA-inducible or constitutive promoter constructs were expressed in transiently cotransformed rice protoplasts and reporter activities quantified by FCM (for GFP) or traditional enzyme assays. Treatments included cotransformations with specific ABA signaling effector cDNA constructs (encoding VIVIPAROUS-1, an ABA transcription factor, and ABA-INSENSITIVE1-1, a dominant-negative protein phosphatase regulator) and the ABA agonist lanthanum chloride. Dual-color FCM was also performed on GFP-expressing cells immunodecorated with an mAb recognizing a rice cell surface epitope. RESULTS: Quantitative analysis of ABA-inducible gene expression by FCM using GFP as reporter gave comparable results to traditional reporter enzyme assays, although the signal-to-noise ratio was less for FCM, which can be a limitation of the method at low promoter strengths. Multiparameter-correlated analysis of ABA-inducible GFP expression with a plasma membrane marker showed no apparent correlation between ABA sensitivity, marked by GFP, and presence of a cell surface arabinogalactan glycoprotein. CONCLUSIONS: Quantitative FCM of GFP-expressing plant cells is a rapid, robust, reproducible, and value-added method relative to traditional enzymatic reporter gene assays.

Abscisic Acid↗
PubMed1979

Quantitative analysis of tiamenidine in human plasma by gas chromatography mass spectrometry of a dibenzyl derivative.

A gas chromatography mass spectrometry method has been developed and evaluated for the quantitative analysis of tiamenidine in plasma. Tiamenidine and internal standard are extracted from basified plasma, converted to dibenzyl derivatives by reaction with benzyl bromide and potassium t-butoxide in the presence of 18-crown-6 ether prior to analysis by selected ion monitoring. The method can be used over the range 0.2--10 ng ml-1 with a coefficient of variation of better than 20% at 1 ng ml-1.

Alkylation↗
PubMed2003

Quantitative analysis of three-dimensional rendered imaging of the human skull acquired from multi-detector row computed tomography.

The purpose of this study was to evaluate the quantitative accuracy of three-dimensional (3D) rendered images acquired with multi-detector row computed tomography (MDCT) by means of distance measurements of a dry human skull for various slice thicknesses and acquisition modes. A radiologist directly measured the distance of line items on the skull surface to establish reference "gold standards." The skull specimen was scanned with a MDCT with various scanning parameters (slice thicknesses and acquisition modes). An observer measured the corresponding distances of the same items on 3D rendered images. The quantitative accuracy of distance measurements was statistically evaluated. There were no significant statistical differences (P value <.05) in accuracy of distance measurements among the scan modes. However, the results showed that acquisition slice thickness was the influential factor in determining the accuracy of the 3D rendered MDCT images. The quantitative analysis of distance measurement may be a useful tool evaluating the accuracy and defining optimal parameters of 3D rendered images.

Analysis of Variance↗
PubMed2006

Quantitative analysis of lovastatin in capsule of Chinese medicine monascus by capillary zone electrophoresis with UV-vis detector.

A capillary zone electrophoresis (CZE) method was developed for the quantitative analysis of lovastatin (Lvt) in capsule of monascus-Chinese medicine. Lvt in the capsule was separated using an electrolyte system consisting of 16% ethanol (v/v) in 60 mM Gly-sodium hydroxide buffer, pH 10.5, 16 kV applied voltage, 238 nm detection wavelength with a capillary of 51 cm x 75 microm i.d (43 cm to detector). Under the optimized conditions, the linear response of Lvt concentration ranges from 4.0 to 240 microg/mL with high correlation coefficient (r=0.9998, n=9), the limits of detection (LOD) and quantification (LOQ) for Lvt are 0.73 and 2.42 microg/mL, the precision values (expressed as R.S.D.) of intra-day and inter-day are 1.40-2.12% and 1.47-3.88%, respectively. The recoveries of the analyte at three concentration levels are 90.28-100.71%. The developed method can be well used for the quantification of Lvt in the drug in commercial formulations.

Buffers↗
PubMed2002

Quantitative analysis of the relative transcript levels of ABC transporter Atr genes in Aspergillus nidulans by real-time reverse transcription-PCR assay.

The development of assays for quantitative analysis of the relative transcript levels of ABC transporter genes by real-time reverse transcription-PCR (RT-PCR) might provide important information about multidrug resistance in filamentous fungi. Here, we evaluate the potential of real-time RT-PCR to quantify the relative transcript levels of ABC transporter Atr genes from Aspergillus nidulans. The AtrA to AtrD genes showed different and higher levels in the presence of structurally unrelated drugs, such as camptothecin, imazalil, itraconazole, hygromycin, and 4-nitroquinoline oxide. We also verified the relative transcript levels of the Atr genes in the A. nidulans imazalil-resistant mutants. These genes displayed a very complex pattern in different ima genetic backgrounds. The imaB mutant has higher basal transcript levels of AtrB and -D than those of the wild-type strain. The levels of these two genes are comparable when the imaB mutant is grown in the presence and absence of imazalil. The imaC, -D, and -H mutants have higher basal levels of AtrA than that of the wild type. The same behavior is observed for the relative transcript levels of AtrB in the imaG mutant background.

ATP-Binding Cassette Transporters↗
PubMedDate not supplied

Dementia in the oldest-old: quantitative analysis of 12 cases from a psychiatric hospital.

To examine the neuropathological characteristics of senile dementia of the Alzheimer type (SDAT) in very old people, we performed a quantitative analysis of the distribution of neurofibrillary tangles and senile plaques in the brains of 12 demented patients aged from 96 of 104 years. The hippocampal formation and the inferior temporal cortex displayed numerous neurofibrillary tangles in most cases, whereas the superior frontal cortex was relatively spared. The only statistically significant difference between demented and control cases was in the density of neurofibrillary tangles in the CA1 field of the hippocampus. High senile plaque densities were observed in the cerebral cortex and were correlated with the duration of SDAT. These results confirm the crucial role of the hippocampus in the neuropathological diagnosis of SDAT in oldest-old patients. Furthermore, they suggest that senile plaque formation may be a pathological hallmark of severe SDAT in this particular age group.

Aged↗
PubMed1997

Quantitative analysis of alkylpyrazines in regular- and low-fat commercial peanut butter preparations.

A simple, modified version of the selective purge and trap method was applied for a quantitative analysis of the trace amount of pyrazines present in both regular- and low-fat commercial peanut butter preparations. A total of 33 volatile compounds were identified, the three most abundant individual pyrazines being 2,5 (or 2,6)-dimethylpyrazine, 2-ethyl-6-methylpyrazine, and pyrazine which comprised 55-79% of the total pyrazine concentration. Minor or trace quantities of thiazoles, oxazoles, pyrroles, and pyridine were also identified in the sample.

Arachis↗
PubMed2001

[A study of the correlation between p16 protein expression and DNA quantitative analysis in human gastric carcinoma cells].

OBJECTIVE: To investigate p16 protein expression and its correlation with DNA quantity in gastric carcinoma (GC) cells. METHODS: p16 protein expression was quantitatively determined by flow cytometry (FCM) in 41 cases of GC and 10 cases of normal gastric tissues. DNA quantitative analysis of 41 cases of GC was performed by image cytometry (ICM). RESULTS: p16 protein expression in GC was significantly lower than that in normal gastric tissues (respective FI: 0.81 plus minus 0.09 and 1.00 plus minus 0.11, P < 0.01). The expression of p16 protein did not show correlation with such factors as sex and age in GC, but it was significantly stronger in well differentiated GC than that in poorly differentiated GC (P < 0.05). The mean of DNA relative ploid (U value) in GC was from 1.14 to 2.98. U value becomes higher with the increase in grading (P < 0.01). There was significant negative linear correlation between p16 protein expression and U value in GC (P < 0.01). CONCLUSION: Abnormal expression of p16 protein is closely correlated to the occurrence, development and malignancy degree of GC. The level of p16 protein expression implies important clinical significance for GC treatment and may serve as an indicator to predict the prognosis of patients.

Adenocarcinoma↗
PubMed1990

Quantitative analysis of the glucocorticoid receptor-DNA interaction at the mouse mammary tumor virus glucocorticoid response element.

Purified glucocorticoid receptor (GR) from rat liver was used for a quantitative analysis of the protein-DNA interaction at specific GR-binding segments within the 5'-long terminal repeat of the mouse mammary tumor virus. A truncated receptor was generated and used to demonstrate formation of heterodimeric GR, which furthermore was shown to be in rapid equilibrium with receptor-monomer. The relative affinity for GR binding to specific GR sites versus random calf thymus DNA was approximately 2 x 10(3). At equilibrium a free GR concentration of 3 x 10(-10) M was required for half-maximal saturation of the two functionally important DNA sites within the mouse mammary tumor virus 5'-long terminal repeat. Although these two DNA segments act synergistically in mediating hormonal response, we did not detect cooperative GR binding to these regions in vitro. However, GR bound cooperatively within the downstream binding region. Similarly, GR was unable to facilitate factor binding to a neighboring nuclear factor 1 site, another essential element in the promoter. In contrast, nuclear factor 1 binding was inhibited slightly by GR.

Animals↗
PubMed1990

Quantitative analysis of tomographic stress thallium-201 myocardial scintigrams: a multicenter trial.

The accuracy of the previously developed and validated Cedars-Sinai Medical Center (CSMC) computer program for quantitative analysis of thallium-201 (201TI) stress myocardial tomograms was assessed in a multicenter trial consisting of 242 patients with coronary angiography and 76 with a low likelihood (LL) of coronary artery disease (CAD) involving various cameras, computers, and operators. The program utilized gender-matched normal limits developed from 35 LL patients at CSMC. The multicenter results as compared to those of 168 patients from CSMC were not significantly different with respect to the overall sensitivities (94% versus 95%) and specificities (44% versus 56%) for identification of CAD and normalcy rates which were determined in LL patients (82% for both) and with respect to identification of individual diseased arteries. The results indicate that our method for quantifying tomographic 201TI stress scintigrams utilizing standard normal limits can be applied at other institutions by different operators, using a variety of cameras and computers, with similar accuracy to that currently obtained at our institution.

Coronary Disease↗
PubMed1985

Computer-assisted sequential quantitative analysis of gallium scans in pulmonary sarcoidosis.

Fifty-one sequential gallium citrate scans were performed in 22 patients with biopsy-proven sarcoidosis. A computer-assisted quantitative analysis of these scans was performed to obtain a gallium score. The changes in gallium score were correlated with changes in serum angiotensin converting enzyme (SACE) activity and objective changes in clinical status. There was a good concordance between changes in gallium score, SACE activity and clinical assessment in patients with sarcoidosis, and changes in gallium index were slightly superior to SACE index in assessing activity of sarcoidosis.

Adult↗
PubMedDate not supplied

[Quantitative analysis of repetitive sequences in human genomic DNA and detection of an elevated ribosomal repeat copy number in patients with schizophrenia (the results of molecular and cytogenetic analysis)].

A modified version of quantitating repetitive sequences in genomic DNA was developed to allow comparisons for numerous individual genomes and simultaneous analysis of several sequences in each DNA specimen. The relative genomic content of ribosomal repeats (rDNA) was estimated for 75 individuals, including 33 healthy donors (HD) and 42 schizophrenic patients (SP). The rDNA copy number in HD was 427 +/- 18 (mean SE) per diploid nucleus, ranging 250-600. In SP, the rDNA copy number was 494 +/- 15 and ranged 280-670, being significantly higher than in HD. The two samples did not differ in contents of sequences hybridizing with probes directed to a subfraction of human satellite III or to the histone genes. Cytogenetic analysis (silver staining of metaphase chromosomes) showed that the content of active rRNA genes in nucleolus organizer regions is higher in SP compared with HD. The possible causes of the elevated rRNA gene dosage in SP were considered. The method employed was proposed for studying the polymorphism for genomic content of various repeats in higher organisms, including humans.

Adolescent↗
PubMed1988

Quantitative analysis of intramembranous particles in rapidly frozen 10T1/2 cell monolayers.

A simple method for ultrarapid freezing of cell cultures in monolayers was developed. Unfixed and unglycerinated cells were grown on glass substrates. No special treatments of the glass or cells were necessary to facilitate freeze-fracture along the upper plasma membranes. A reliable nonbiased method was developed to detect intramembranous particles (IMP) from the background by totally automatic means using the Cambridge Instruments Quantimet 920 Image Analysis system. Size and density data of IMP from a large number of electron micrographs can be rapidly and objectively quantitated. The automatic determination of locational coordinates for each IMP enables subtle determination of spatial distributional differences by the nearest neighbour function and the differential density distribution function, which are measurements of randomness. Quantitative analysis of the IMP distribution on the fracture face of C3H/10T1/2 mouse embryo fibroblasts upon various drug treatments was demonstrated.

Animals↗
PubMed1998

Simultaneous quantitative analysis of methyl salicylate, ethyl salicylate and salicylic acid from biological fluids using gas chromatography-mass spectrometry.

A gas chromatographic-mass spectrometric (GC-MS) assay was developed for the quantitative analysis of methyl salicylate (MeS), ethyl salicylate (ES) and salicylic acid (SA) from biological fluids. The method was validated from 100-microl rat liver homogenate preparations (5 mg/ml protein) in 70 mM KH2PO4 (pH 7.4) buffer and from 100 microl rat plasma. The samples were extracted with chloroform, derivatized with BSTFA and quantitated by GC-MS in the SIM mode. The standard curves ranged from 31 ng/ml to 800 or 1250 ng/ml. Relative standard deviations and bias were less than 11% in plasma and homogenate for all compounds except SA which evidenced greater variability. The assay was used in preliminary experiments to characterize the pharmacokinetics of MeS in rats.

Animals↗
PubMed2006

Calibration by NMR for quantitative analysis: p-toluenesulfonic acid as a reference substance.

We have demonstrated the usefulness of p-toluenesulfonic acid (TsOH) as a reference substance to calibrate a water-soluble standard by NMR for quantitative analysis. In order to make TsOH convenient for this purpose, we first of all established its molar extinction coefficient under these conditions (epsilon = 351 at 262 nm). This was done by comparing it by quantitative NMR (qNMR) with a compound of known molar extinction coefficient, guanosine monophosphate. TsOH was then used as the standard in a second qNMR experiment to measure an aqueous solution of phosphoglycolate, a metabolite of interest in our laboratory. Perhaps due to its content of water, the purity of this compound was found to be 82%, lower than the value of 94% from the manufacturer.

Benzenesulfonates↗
PubMed2003

Quantitative analysis of ES-285, an investigational marine anticancer drug, in human, mouse, rat, and dog plasma using coupled liquid chromatography and tandem mass spectrometry.

A method was developed for the quantitative analysis of the novel anticancer agent ES-285 (spisulosine; free base) in human, mouse, rat, and dog plasma using high-performance liquid chromatography/electrospray ionization tandem mass spectrometry in order to support pre-clinical and clinical studies with the drug. Sample preparation was carried out by protein precipitation with acetonitrile, containing isotopically labeled (d(3)) ES-285 as internal standard. Aliquots of 10 micro l of the supernatant were injected directly on to an Inertsil ODS-3 column (50 x 2.0 mm i.d., 5 micro m). Elution was carried out using methanol-10 mM ammonium formate (pH 4) in water (80 : 20, v/v) pumped at a flow-rate of 0.2 ml min(-1) with a run time of 8 min. Multiple reaction monitoring chromatograms obtained on an API365 triple-quadrupole mass spectrometer were used for quantification. The lower limit of quantitation (LLOQ) was 10 ng ml(-1) in human, mouse, rat, and dog plasma and the linear dynamic range extended to 500 ng ml(-1). A full validation of the method was performed in human plasma, and partial validations were performed in mouse, rat and dog plasma. Accuracies and precisions were <20% at the LLOQ concentration and <15% for all other concentrations in all matrices. ES-285 was stable during all steps of the assay. Thus far this method has been used successfully to analyze over 500 samples in pre-clinical trials, and will be implemented in the planned clinical phase I studies.

Alkanes↗
PubMed2004

Quantitative analysis of granule cell axons and climbing fiber afferents in the turtle cerebellar cortex.

The turtle cerebellar cortex is a single flat sheet of gray matter that greatly facilitates quantitative analysis of biotylinated dextran amine labeled granule cell and olivocerebellar axons and Nissl-stained granule and Purkinje neurons. On average, ascending granule cell axons are relatively thicker than their parallel fiber branches (mean +/- SD: 0.84 +/- 0.17 vs 0.64 +/- 0.12 microm, respectively). Numerous en passant swellings, the site of presynaptic contact, were present on both ascending and parallel fiber granule cell axons. The swellings on ascending axons (1.82 +/- 0.34 microm, n = 52) were slightly larger than on parallel fibers (1.43 +/- 0.24 microm, n = 430). In addition, per unit length (100 microm) there were more swellings on ascending axons (11.2 +/- 4.2) than on parallel fibers (9.7 +/- 4.2). Each parallel fiber branch from an ascending axon is approximately 1.5 mm long. Olivocerebellar climbing fiber axons followed the highly tortuous dendrites of Purkinje cells in the inner most 15-20% of the molecular layer. Climbing fibers displayed relatively fewer en passant swellings. The spatial perimeter of climbing fiber arbors (area) increased 72% from anteriorly (1797 microm2) to posteriorly (3090 microm2) and 104% from medially (1690 microm2) to laterally (3450 microm2). Differences in the size and spacing of en passant swellings on granule cell axons suggest that ascending axons may have a functionally more significant impact on the excitability of a limited number of radially overlying Purkinje cells than the single contacts by parallel fiber with multiple orthogonally aligned Purkinje cell dendrites. The spatially restricted distribution of climbing fibers to the inner most molecular layer, the paucity of en passant swellings, and different terminal arbor areas are enigmatic. Nevertheless, these finding provide important anatomical information for future optical imaging and electrophysiological experiments.

Afferent Pathways↗