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PubMed1998

[Magnetic resonance in the study of suprarenal neoplasms. Qualitative and quantitative analysis of signal intensity].

INTRODUCTION: Magnetic Resonance Imaging (MRI) has been proposed as the diagnostic technique of choice to characterize adrenal tumors. However, the results of the current studies are controversial. MATERIAL AND METHODS: Forty-nine patients with unilateral adrenal masses were submitted to MRI for lesion characterization on the basis of MR signal intensity. Cytology and/or histology demonstrated 14 pheochromocytomas (pheos), 11 adenomas, 3 cysts, 2 myelolipomas, 4 carcinomas, 3 metastases and 1 fibrosarcoma; a clinical diagnosis of adenoma was made in the remaining 11 patients. MR studies were performed using spin-echo (SE) sequences with T1 (TR/TE = 600/17 ms) and T2 (TR/TE = 2000/15-90 ms) weighting. T1-weighted images were also acquired after Gadolinium-DTPA (Gd-DTPA) administration. MR studies were integrated with in- and out-of-phase (TR/TE = 100/4-6 ms) chemical-shift (CS) sequences. MR signal intensity (SI) was analyzed qualitatively and quantitatively; MR results were correlated with tumor type and hormone secretion. RESULTS: The qualitative analysis of T2 images showed high signal intensity in the majority (80%) of adrenal lesions (14 pheos, 12 adenomas, 3 cysts, 2 myelolipomas and 8 malignancies). The quantitative analysis of post-Gd-DTPA T1 images permitted to distinguish adenomas, cysts and myelolipomas from pheos and malignancies. The qualitative analysis of post-Gd-DTPA T2 and T1 images permitted to distinguish pheos and cysts from adenomas and malignancies (p < .05); however, pheos and cysts as well as adenomas and malignancies were not differentiated. MR SI was similar in secreting and nonsecreting adenomas from both a qualitative and a quantitative viewpoints. CS MRI permitted to distinguish adenomas (decreased signal intensity on out-phase relative to in-phase images) from other benign and malignant lesions (no signal change from out-phase to in-phase images). CONCLUSIONS: The qualitative analysis of MR SI on conventional T1 and T2 images does not permit to differentiate adrenal masses. The qualitative evaluation of T1 images after Gd-DTPA administration, the quantitative analysis and CS sequences are technical options improving lesion characterization.

Adrenal Gland Neoplasms↗
PubMed1983

Clinical evaluation of seven-pinhole tomography for the detection and localization of coronary artery disease: comparison with planar imaging using quantitative analysis of myocardial thallium-201 distribution and washout after exercise.

The development of quantitative techniques to assist in the analysis of planar thallium-201 stress-redistribution scintigrams has led to improved abilities of this modality to detect the presence of and to localize significant coronary artery disease (CAD). This fact has encouraged the reevaluation of its capabilities relative to other types of scintigraphic data collection, including seven-pinhole tomography. We have undertaken a comparison of planar scintigraphy and seven-pinhole tomography to detect in 40 exercised patients (23 with angiographically demonstrated CAD, eight with normal coronary angiograms, and nine with less than or equal to 1% likelihood of having CAD) the presence of significant CAD and to localize it correctly to an individual coronary artery. Emphasis was placed on similar imaging conditions and on analysis of images by the same quantitative program of TI-201 distribution and washout. Both techniques were found to be highly sensitive and specific for disease detection and localization. Importantly, seven-pinhole tomography did not significantly improve results.

Coronary Disease↗
PubMed1994

Quantitative analysis of immunohistological changes in the synovial membrane of sheep infected with Maedi-Visna virus.

We have carried out a quantitative immunohistological analysis of synovial membrane from the joints of clinically arthritic sheep naturally infected with Maedi-Visna virus (MVV) and compared the results to subclinically affected joints (carpal and tarsal) from infected sheep and to joints from a control population. Significantly elevated numbers of all three T lymphocyte subsets (CD4+, CD8+ and gamma delta) were found in the synovia from clinically arthritic sheep compared to controls. There was also a significant increase in the number of CD8+ T lymphocytes in the carpal synovium of subclinically arthritic animals. In both clinically arthritic and subclinical disease states CD8+ T cells predominated over CD4+ T cells and T cells bearing the gamma delta T cell receptor. Significant increases were also observed in the numbers of cells staining for MHC class II antigens in the synovial lining cell layer and subintimal cell populations of synovia from clinically arthritic sheep. These increases were apparent in the subintimal cell population at the subclinical stage of disease. Macrophage-like cells staining for the viral core protein p15 were observed in some of the most inflamed samples. The data are thus consistent with a disease process driven by chronic viral antigen presentation to infiltrating T cells, and could serve as a model for elucidating the mechanisms underlying some types of inflammatory joint disease in man.

Animals↗
PubMed1981

Qualitative and quantitative analysis of some synthetic, chemically acting laxatives in urine by gas chromatography-mass spectrometry.

A method for the qualitative and quantitative simultaneous analysis of dioxyanthraquinone, desacetyl-Bisacodyl, phenolphthalein and Oxyphenisatin in human urine using gas chromatography-mass spectrometry (GC-MS) has been developed. The compounds were extracted from urine at pH 7.5 with diethyl ether using Extrelut extraction columns, followed by evaporation and trimethylsilylation. The method used electron beam ionization GC-MS employing a computer-controlled multiple-ion detector (mass fragmentography). The recovery from urine for the various compounds was between 80% and 100%. The detection limit for these compounds was in the range 0.01--0.05 micrograms/ml of urine. The method proved to be suitable for measuring urine concentrations for at least four days after administration of a single oral low therapeutic dose of the laxatives to sixteen healthy volunteers.

Anthraquinones↗
PubMed1987

Qualitative and quantitative analysis of tumour invasion in vivo and in vitro.

Qualitative and quantitative methods for the analysis of invasion in 'natural' and in experimental tumours in vivo and in vitro are reviewed. In human tumours the functional consequences of invasion were evaluated histologically through staging on the basis of depths of invasion and through the presence of tumour cells inside vessels. Antibodies against components of the basement membrane have facilitated the definition of minimal invasion. With new probes derived from oncogene research the search for molecular differences between invasive and non-invasive parts of the tumour has begun. Since the same methods as those used for analysis of natural tumours also apply to experimental tumours in vivo, the major advantage of the latter is the possibility of manipulation. We have described a new mesenterium assay that may permit the selection of invasive cells from non-invasive ones in transfection experiments. Invasion relative to growth as a function of time was quantified in the kidney invasion test. In three-dimensional confrontations between embryonic chick heart fragments and invasive cells, we have used both a subjective grading and a qualitative computer-assisted image analysis of serial histological sections to score invasion. In two-dimensional confrontations supplementary methods could be applied, since such confrontations permitted direct observations on living cultures. In a variety of natural and experimental tumours, ultrastructural analysis, transmigration in two-compartment chambers, and release of metabolic label have demonstrated the role of motility and of lytic activity in tumour invasion.

Animals↗
PubMed2006

A quantitative analysis of bleeding symptoms in type 1 von Willebrand disease: results from a multicenter European study (MCMDM-1 VWD).

BACKGROUND: A quantitative description of bleeding symptoms in type 1 von Willebrand disease (VWD) has never been reported. OBJECTIVES: The aim was to quantitatively evaluate the severity of bleeding symptoms in type 1 VWD and its correlation with clinical and laboratory features. PATIENTS AND METHODS: Bleeding symptoms were retrospectively recorded in a European cohort of VWD type 1 families, and for each subject a quantitative bleeding score (BS) was obtained together with phenotypic tests. RESULTS: A total of 712 subjects belonging to 144 families and 195 controls were available for analysis. The BS was higher in index cases than in affected family members (BS 9 vs. 5, P < 0.0001) and in unaffected family members than in controls (BS 0 vs. -1, P < 0.0001). There was no effect of ABO blood group. BS showed a strong significant inverse relation with either von Willebrand ristocetin cofactor (VWF:RCo), von Willebrand antigen (VWF:Ag) or factor VIII procoagulant activity (FVIII:C) measured at time of enrollment, even after adjustment for age, sex and blood group (P < 0.001 for all the four upper quintiles of BS vs. the first quintile, for either VWF:RCo, VWF:Ag or FVIII:C). Higher BS was related with increasing likelihood of VWD, and a mucocutaneous BS (computed from spontaneous, mucocutaneous symptoms) was strongly associated with bleeding after surgery or tooth extraction. CONCLUSIONS: Quantitative analysis of bleeding symptoms is potentially useful for a more accurate diagnosis of type 1 VWD and to develop guidelines for its optimal treatment.

ABO Blood-Group System↗
PubMed1999

Quantitative analysis of cimetidine in human plasma using LC/APCI/SRM/MS.

A quantitative method was developed and validated for rapid and sensitive analysis of cimetidine in human plasma. The method involved the use of liquid chromatography (LC) coupled with atmospheric pressure chemical ionization (APCI) and selected reaction monitoring (SRM) mass spectrometry (MS). A cimetidine analog, SKF92374, was used as the internal standard. Separation of cimetidine and the internal standard was accomplished using a reverse-phase HPLC column (C18). The eluted components were ionized by the APCI source and subsequently detected by a highly selective triple quadrupole mass spectrometer in the SRM mode. Linear standard curves were obtained from 5 ng/mL (lower limit of quantitation) to 10,000 ng/mL. The results demonstrated excellent precision (%RSD 1. 1-8.9%) and accuracy (94.7-108.0%) over this range. In addition, the amount of plasma sample needed for analysis was small (50 muL), and the plasma pretreatment (analyte recovery >94%) was simple and time saving. This assay was used to evaluate cimetidine levels in premature infants following intravenous infusion of cimetidine.

Child↗
PubMed1987

A quantitative analysis of the human bone marrow erythroblastic cell lineage using the SAMBA 200 cell image processor. I. The normal maturation sequence.

A quantitative image analysis of the normal maturation sequence for the human bone marrow erythroblastic lineage was performed using the SAMBA 200 cell image processor. The different image analysis steps (image acquisition, preprocessing, segmentation, parametrization and data analysis) are briefly described. Thirty-three parameters related to geometry, color, texture and densitometry were computed on 638 cell images belonging to the five erythroblastic maturation stages. The automated classification of these cells, based upon a stepwise linear discriminant analysis, resulted in 80% correctly classified cells. Acceptance of confusions between successive maturation stages enhanced the rate of correctly classified cells to 100%. Among the ten most discriminating parameters, the nuclear area showed the highest correlation with the changes throughout the maturation process. The projection of the maturation sequence onto the factorial plane resulting from the canonical analysis emphasizes the existence of three phases of the maturation process, a finding that correlates well with the cytologic evolution and the biochemical and functional events during the maturation. The trajectory of cells within this factorial plane is thus regarded as a differentiation path from which a measure of the maturation could be derived.

Bone Marrow Cells↗
PubMed1984

A quantitative analysis of the human bone marrow granulocytic cell lineage using the SAMBA 200 cell image processor. I. The normal maturation sequence.

A quantitative image analysis of the human normal bone marrow granulocytic line was performed using the SAMBA 200 image analyzer. The steps of image acquisition, preprocessing, segmentation and parametrization are described. Forty-one parameters were computed on 941 cell images belonging to the various maturation stages. The automated classification of these cells based upon a stepwise linear discriminant analysis resulted in 77% correctly classified cells; the five most discriminating parameters were the nuclear area, the nuclear convexity degree, the average cytoplasmic hue, the regularity of the nuclear boundary and the average cytoplasmic luminance. The evolution of the parameters correlates well with the cytologic evolution and the biochemical and functional events during the maturation process. It can be inferred from our results that the maturation sequence can be subdivided into two phases according to the evolution of the cell profiles. The first phase, from myeloblast to myelocyte, is discontinuous and appears as the critical point with regard to the expression of genes. The second phase, from myelocyte to polymorphonuclear cell, is a continuous sequence of transformations leading to the functional granulocyte.

Autoanalysis↗
PubMed1993

Quantitative analysis of polymerase chain reaction products using biotinylated dUTP incorporation.

A method for relative quantitation of specific mRNA species by polymerase chain reaction (PCR) has been developed by using the incorporation of biotinylated dUTP. Transferred biotinylated PCR products gave a sensitive colorimetric signal which could be quantitated by video analysis. In the exponential phase of amplification, the linearity and reproducibility of reverse transcription and PCR demonstrated the same efficiency of cDNA synthesis and PCR for the two target genes, ICAM-1 and beta-actin, and allowed the normalization of ICAM-1 expression. These results suggested that in the exponential phase of amplification a relative quantitation of mRNA could be determined. We used this approach to analyze the different effects of TNF-alpha, IL-1 beta, and purified porcine platelet-derived growth factor stimulations on ICAM-1 expression in smooth muscle cells.

Base Sequence↗
PubMed2000

Quantitative analysis of cell allocation during liver development, using the spf(ash)-heterozygous female mouse.

Mosaicism of ornithine transcarbamylase (OTC) expression in hepatocytes was quantitatively analyzed during liver development of the spf(ash)-heterozygous female mouse. Because the mosaic patterns depend on cell migration and cell mixing, such analysis could give insights on the growth pattern or allocation pattern of hepatocytes during liver development. Complex mosaic patterns of OTC-positive and -negative hepatocytes were observed in sections of fetal and postnatal livers. Sizes of patches, which were aggregates of OTC-positive or -negative hepatocytes, increased during development. Patches were slender and comparatively simple in 15.5- and 17.5-day fetal and neonatal livers. Quantitative analysis of patch shapes demonstrated that undulation of patches was maximal at 7 postnatal days. Patches with nodular shapes also started to increase in number at this stage. Isolated patches in sections of fetal livers and postnatal livers three-dimensionally connected with one another. However, especially in fetal livers, in which OTC-positive patches were minor, due to the presence of abundant hemopoietic cells, isolated three-dimensional patches consisting of approximately 5 to 70 cells were often found. They were shaped like slender branching or zigzag-shaped cords, but no definite orientation such as portal-central was observed in them at any stage. These results suggest that hepatocytes contiguously allocate their daughter cells as zigzag-shaped or branching cords at younger stages. Some hepatocytes grow with nodular formation after 7 postnatal days. Migration and mixing of hepatocytes appear to be more extensive at fetal stages than in the adult liver. Immunohistochemical analysis of intercellular junction proteins (E-cadherin, connexins 26 and 32, occludin, and ZO-1) also revealed that their expression and distribution changed in hepatocytes during development, which may be correlated with the OTC mosaic patterns.

Aging↗
PubMed1995

Quantitative analysis of pulmonary surfactant phospholipids by high-performance liquid chromatography and light-scattering detection.

An improved high-performance liquid chromatographic method for the separation and quantitation of nine phospholipid classes is described. It is based on normal-phase chromatography with silica gel as stationary phase and a binary gradient with mixtures of chloroform, methanol and water as mobile phase. The response of the evaporative light-scattering detector was non-linear. Peak areas were proportional to the power 1.7 of the masses. Phospholipids in lung lavage samples were enriched by liquid extraction prior to HPLC analysis. The described method is a rapid and accurate procedure for the quantitative analysis of phospholipid classes in biological samples.

Adult↗
PubMed2002

Quantitative analysis of telomerase hTERT mRNA and telomerase activity in endometrioid adenocarcinoma and in normal endometrium.

OBJECTIVES: In the current study, the quantitative levels of telomerase hTERT mRNA and the functional telomerase repeat amplification protocol (TRAP) assay were correlated with tumor grade in endometrial carcinomas and with the histologic phase of normal endometrium. METHODS: Twenty-six samples of endometroid adenocarcinoma and 20 cases of benign endometrium were obtained from hysterectomy specimens. Total RNA was extracted from each tissue sample and used for quantitative real-time RT-PCR of hTERT mRNA and the levels were standardized to the levels of ribosomal RNA. Quantitative determination of telomerase activity was performed by the polymerase chain-based TRAP assay and the levels of expression were defined by the ratio of radioactivity incorporated into the 6-bp telomerase amplification products versus the radioactivity incorporated into an internal standard (telomerase/ITAS x 100 = 1 RU). Statistical analyses were performed using the Fisher exact test or chi2 test, a Wilcoxon rank sum test, and a linear regression analysis. RESULTS: hTERT mRNA and telomerase activity levels showed a linear association in the study group (P = 0.006, R2 = 0.139). hTERT mRNA levels and telomerase activity levels were significantly higher in endometrial cancer (179 pg/ng rRNA, 44 relative units (RU)) than in normal endometrium (45 pg/ng), (15 RU) (P = 0.009, P = 0.006). In normal endometrium, hTERT mRNA and telomerase activity levels were highest in the proliferative phase (74 pg/ng rRNA, 25 RU) and were relatively low in secretory (13 pg/ng rRNA, 6 RU) and atrophic endometrium (9 pg/ng rRNA, 2 RU). CONCLUSION: These results suggest that the quantitative analysis of hTERT and telomerase activity may have potential roles as diagnostic or prognostic adjuncts for both premenopausal and postmenopausal patients with endometrial cancer.

Adult↗
PubMed2002

Reproducibility of dynamic contrast-enhanced MRI in human muscle and tumours: comparison of quantitative and semi-quantitative analysis.

The purpose of this study was to determine the reproducibility of dynamic contrast-enhanced (DCE)-MRI and compare quantitative kinetic parameters with semi-quantitative methods, and whole region-of-interest (ROI) with pixel analysis. Twenty-one patients with a range of tumour types underwent paired MRI examinations within a week, of which 16 pairs were evaluable. A proton density-weighted image was obtained prior to a dynamic series of 30 T(1)-weighted spoiled gradient echo images every 11.9 s with an intravenous bolus of gadopentetate dimeglumine given after the third baseline data point. Identical ROIs around the whole tumour and in skeletal muscle were drawn by the same observer on each pair of examinations and used for the reproducibility analysis. Semi-quantitative parameters, gradient, enhancement and AUC (area under the curve) were derived from tissue enhancement curves. Quantitative parameters (K(trans), k(ep), v(e)) were obtained by the application of the Tofts' model. Analysis was performed on data averaged across the whole ROI and on the median value from individual pixels within the ROI. No parameter showed a significant change between examinations. For all parameters except K(trans), the variability was not dependent on the parameter value, so the absolute values for the size of changes needed for significance should be used for future reference rather than percentages. The size of change needed for significance in a group of 16 in tumours for K(trans), k(ep) and v(e) was -14 to +16%, -0.20 ml/ml/min (15%) and -1.9[?]ml/ml (6%), respectively (pixel analysis), and -16 to +19%, -0.23 ml/ml/min (16%) and +/- 1.9[?]ml/ml (6%) (whole ROI analysis). For a single tumour, changes greater than -45 to +83%, +/- 0.78 ml/ml/min (60%) and +/- 7.6 ml/ml (24%), respectively, would be significant (pixel analysis). For gradient, enhancement and AUC the size of change needed for significance in tumours was -0.24 (17%), -0.05 (6%) and -0.06 (8%), respectively for a group of 16 (pixel analysis), and +/- 0.96 (68%), +/- 0.20 (25%) and +/- 0.22 (32%) for individuals. In muscle, the size of change needed for significance in a group of 16 for K(trans), k(ep) and v(e) was -30 to +44%, +/- 0.81 ml/ml/min (61%) and +/- 1.7 ml/ml (13%). For gradient, enhancement and AUC it was +/- 0.09 (20%), +/- 0.02 (8%) and +/- 0.03 (12%). v(e), enhancement and AUC are highly reproducible DCE-MRI parameters. K(trans), k(ep) and gradient have greater variability, with larger changes in individuals required to be statistically significant, but are nevertheless sufficiently reproducible to detect changes greater than 14-17% in a cohort of 16 patients. Pixel analyses slightly improve reproducibility estimates and retain information about spatial heterogeneity. Reproducibility studies are recommended when treatment effects are being monitored.

Antineoplastic Agents↗
PubMed2004

Quantitative analysis of 99mTc-DMSA during acute pyelonephritis for prediction of long-term renal scarring.

UNLABELLED: This study was performed to evaluate a quantitative method based on (99m)Tc-DMSA renal planar scintigraphy performed during acute pyelonephritis (APN) to detect kidneys at risk of scarring. METHODS: A total of 43 children (5.8 +/- 3.6 y old [mean +/- SD]) were examined by (99m)Tc-DMSA scintigraphy during (DMSA 1) and 8 +/- 2 mo after (DMSA 2) APN. Two levels of interpretation were performed independently: first, a semiquantitative analysis to classify the kidneys by considering the evolution between DMSA 1 and DMSA 2 (i.e., to determine which kidneys had developed scarring), and second, an automatic quantitative analysis of DMSA 1 to define and to evaluate a predictive index for kidney evolution from DMSA 1 to DMAS 2. The method consisted of determining an automatic threshold for the kidney and then calculating ratios of the count density in a given isocount n% (region of interest containing all the pixels with a value > or = n% of the value of the pixel with the maximal activity value) to the count density in a 20% isocount (C(n%)) and the number of pixels in a given isocount to the number of pixels in a 20% isocount (S(n%)). RESULTS: All kidneys normal at DMSA 1 remained normal at DMSA 2. For the automatic index, the C(70%) ratio was considered the best index for the prediction of scarring. When this C(70%) ratio was used, a cutoff value of 0.45 was able to predict scarring with a sensitivity of 0.83, a specificity of 0.78, a positive predictive value of 0.85, and a negative predictive value of 0.77. CONCLUSION: A cutoff value of 0.45 for the C(70%) ratio calculated for (99m)Tc-DMSA scintigraphy performed during APN may be useful for detecting kidneys at risk of scarring.

Acute Disease↗
PubMed2006

Quantitative analysis of atherosclerotic lesion composition in mice.

Comparative quantitation has become an increasingly desirable tool in determining compositional differences of aortic plaque lesion in transgenically altered mice. To this end, methodology has been developed to identify lipid, cellularity, collagen, and elastin components using traditional bright-field microscopy, fluorescence, and polarized light microscopy, employing both confocal and wide-field imaging systems. Subsequent imaging processing and analysis on the digitally captured images reveals differences in compositional components as influenced by diet, age and gender. This method can be expanded to employ a rich variety of histochemical and immunohistochemical staining protocols.

Animals↗