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PubMed1999

Image processing techniques for quantitative analysis of skin structures.

Computer-based image processing and analysis techniques were developed for quantitative analysis of skin structures in color histological sections. Performance was compared with traditional non-image processing counting methods. Skin sections were stained with Masson's trichrome, hematoxylin and eosin, picrosirius red, or one of several elastin stains. The image processing software identified the top of the cellular epidermis and the dermal-epidermal junction and then calculated the volume of the cellular layer of the epidermis, epidermal thickness, and the ratio of the dermal-epidermal junction surface area to the in-plane surface area. It also identified cells and collagen and calculated cellular densities and collagen densities in the papillary and reticular layers of the dermis. Attempts to computationally process elastin-stained sections to determine elastin density were unsuccessful. The described techniques were used in a preliminary study to compare mechanically stressed skin with control skin. Results showed significant differences in cellular density in the papillary dermis and collagen density in the reticular dermis for skin subjected to combined shear/compression or tension compared with an unstressed control. Measurements made with the computer technique and traditional technique showed comparable results; the mean difference in measurements for epidermal features was 5.33% while for dermal features it was 2.76%. Significance testing between control and experimental groups showed similar results, though for three of the 28 comparisons the computer method identified a significant difference while the traditional method did not. The computer method took longer to conduct than the traditional method, though with recent advances in computer hardware this time difference would be eliminated.

Adaptation, Physiological↗
PubMed1986

Quantitative analysis of thallium-201 uptake and washout before and after transluminal coronary angioplasty.

Transluminal coronary angioplasty has become an important therapeutic modality in the treatment of coronary artery disease. The effects of coronary angioplasty on regional myocardial perfusion have been reported in only a small series of patients, employing subjective analysis of thallium-201 perfusion scintigrams. Thus, we studied 61 patients with quantitative analysis of thallium-201 uptake and washout before and after undergoing angioplasty. Prior to angioplasty, there were 105 areas in 47 patients with abnormal thallium-201 uptake during exercise, with a mean uptake of 49 +/- 1.3%. The uptake of thallium-201 in these same areas increased to 71.3 +/- 1.9% post angioplasty (P less than 0.0001), and 68 (65%) of the areas showing abnormal uptake returned to normal. Abnormalities in washout of thallium-201 before angioplasty were seen more frequently than in uptake (150 vs 105 areas, P less than 0.05), with 8 patients having abnormal washout in the presence of totally normal uptake. Thallium-201 washout in the abnormal areas improved from 16 +/- 2.8 pre angioplasty to -23 +/- 1.8% post angioplasty (P less than 0.001). Normalization resulted in 6 of the 8 patients with exclusively washout abnormality. Residual abnormalities in uptake and/or washout were seen in 53% of the patients, usually in areas with prior myocardial infarction or supplied by a vessel with significant stenosis which did not undergo angioplasty. Improved thallium-201 uptake and washout corresponded to reductions in percent coronary area stenosis (89 +/- 1.0 to 36 +/- 2.0%, P less than 0.001) and transstenotic pressure gradient (42 +/- 3.0 to 9.0 +/- 2.0 mm Hg, P less than 0.001). Thus, quantitative analysis of thallium-201 uptake and washout provided objective evidence for improved myocardial perfusion after coronary angioplasty. Due to a fairly high prevalence of residual perfusion abnormalities after this procedure, optimal assessment of benefits requires quantitative comparison of thallium uptake and washout before and after coronary angioplasty.

Adult↗
PubMed1988

Bone trabecular pattern analysis in Down's syndrome with the use of computed panoramic tomography with a laser scan system. Quantitative analysis with the power spectrum method.

A quantitative analysis of the mandibular bone trabeculae of 44 patients with Down's syndrome and 68 normal persons by means of panoramic tomography was performed with a laser scan system. The results showed that the normal persons exhibited a correlation between the trabecular pattern and aging, whereas the patients with Down's syndrome showed no such correlation. These findings were consistent with geromorphism, which is one of the systemic features of Down's syndrome.

Adult↗
PubMed1986

Quantitative analysis of type X-collagen biosynthesis by embryonic-chick sternal cartilage.

We have performed a quantitative analysis of the various collagens biosynthesized by organ cultures of whole embryonic-chick sternum and its separate anatomical regions corresponding to the zones of permanent hyaline and presumptive-calcification cartilages. Our studies demonstrated that embryonic-chick sternum devotes a large portion of its biosynthetic commitment towards production of Type X collagen, which represented approx. 18% of the total newly synthesized collagen. Comparison of the collagens biosynthesized by the permanent hyaline cartilage and by the cartilage from the presumptive-calcification zone demonstrated that Type X-collagen production was strictly confined to the presumptive-calcification region. Sequential extraction of the newly synthesized Type X collagen demonstrated the existence of two separate populations. One population (approx. 20%) was composed of easily extractable molecules that were solubilized with 1.0 m-NaCl/50 mM-Tris/HCI buffer, pH 7.4. The second population was composed of molecules that were not extractable even after repeated pepsin digestion, but became completely solubilized after treatment with 20 mM-dithiothreitol/0.15 M-NaCl buffer at neutral pH. These results suggest that most of the Type X collagen normally exists in the tissue as part of a pepsin-resistant molecular aggregate that may be stabilized by disulphide bonds. Quantitative analysis of the proportion of Type X collagen relative to the other collagens synthesized in the cultures indicated that this collagen was a major biosynthetic product of the presumptive-calcification cartilage, since it represented about 35% of the total collagen synthesized by this tissue. In contrast, the permanent hyaline cartilage did not display any detectable synthesis of Type X collagen. When compared on a per-cell basis, the chondrocytes from the presumptive-calcification zone synthesized approx. 33% more Type X collagen than the amount of Type II collagen synthesized by the chondrocytes from the permanent-hyaline-cartilage zone. Subsequently, it was demonstrated that Type X collagen is a structural component of chick sternum matrix, since quantitative amounts could be extracted from the region of presumptive calcification of 17-day-old chick-embryo sterna and from the calcified portion of adult-chick sterna. The strict topographic distribution in the expression of Type X collagen biosynthesis to the zone of presumptive calcification suggests that this collagen may play an important role in initiation or progression of tissue calcification.

Amino Acids↗
PubMed1990

Transmission electron microscopic x-ray quantitative analysis of human dentin at 200 kV accelerating voltage.

Qualitative and quantitative x-ray energy dispersive spectroscopy is now used successfully to analyze many features and processes in inorganic samples. When applied to inorganic samples, however, the results are often less satisfactory due to problems of preparation of organic samples, difficulty of measuring x-rays from organic samples, damage of the sample by the electron beam, and other practical problems. In the present study we used a high voltage transmission electron microscope equipped with an energy dispersive x-ray spectrometer to examine accurate quantitative standardless analysis of thin sections of an organic sample, human dentin. Based on our experiments we found the important parameters for quantitative analysis were sample thickness and appropriate choice of model sample. Further, we show that the method of Cliff and Lorimer can be used with biological samples at 200 kV, and we show that quantitative analysis of human dentin can be carried out at 200 kV. Finally, we show that areas of human dentin can be differentiated by their morphological characteristics and x-ray analyses obtained in the transmission electron microscope.

Child↗
PubMed1999

Color Doppler energy and related quantitative analysis of gestational trophoblastic tumors.

OBJECTIVE: To assess the reliability of color Doppler energy (CDE) and a related quantitative analysis for detection and follow-up of uterine involvement in gestational trophoblastic tumor. METHOD: CDE was performed in 19 patients with trophoblastic tumor, in 25 women in early pregnancy and 25 non-pregnant women. The blood flow area ratio (BFAR) in CDE was used as an index representing uterine involvement. In nine of the 19 patients, BFAR was measured before, during and at termination of chemotherapy. RESULT: The BFAR (mean +/- S.D.) of uterine profiles in 19 patients (39.9 +/- 1.3%) was significantly higher than that in 25 pregnant women (24.6 +/- 10.1%, P = 0.002) and in 25 non-pregnant women (14.8 +/- 5.7%, P = 0.001). In the follow-up of nine patients, when beta-hCG was less than 3.1 ng/ml during the treatment, the BFAR (38.7 +/- 11.9%) decreased below that (44.2 +/- 14.6%) seen prior to treatment (P = 0.009) and was much lower at termination of treatment (27.5 +/- 12.3%, P = 0.048). CONCLUSION: These data support the use of CDE and the related quantitative analysis as a new method for detecting and follow-up of uterine involvement in patients with trophoblastic tumors.

Adult↗
PubMed1989

[Development of a new quantitative analysis for thallium myocardial SPECT images--quantitative STEREO-VIEW method and evaluation of its clinical usefulness].

We have developed a three-dimensional quantitative display method, Quantitative STEREO-VIEW method (STEREO-VIEW method), for analysis of thallium (Tl) myocardial SPECT images and have evaluated its clinical usefulness. SPECT data were obtained immediately and 4 hours after the exercise, and contour lines for outer edges of left ventricular (LV) myocardium were detected from 10 slices of short axial images in delayed scan. LV wall was divided into 510 segments by dividing each slice into 51 sectors and LV myocardium was three-dimensionally reconstructed. Mean Tl counts, %T1 uptake and washout rate (WR) of each segment were calculated and these values were represented such as infarcted area display, redistribution display and WR display on STEREO-VIEW. Furthermore, extent index (EI), severity index (SI) and intensity index (II) were defined to express the degree of perfusion abnormality using WR value of each segment. In the 25 patients with coronary revascularization, improving rate of these indices correlated well with that of double product significantly. STEREO-VIEW method resembled in the original shape of left ventricle of each patient, so STEREO-VIEW method has made it easier to discriminate the accurate extent of ischemic lesion. In addition, EI, SI and II using WR were good indices for coronary perfusion and these were thought to be useful on clinical study.

Aged↗
PubMed1996

Quantitative analysis of hyaluronan in human synovial fluid using capillary electrophoresis.

The glycosaminoglycan, hyaluronan, can be detected in human synovial fluid by capillary electrophoresis (CE). Variations in peak shape make this technique unsuitable for quantitative analysis of hyaluronan in raw synovial fluid. Quantitative analysis was achieved by hydrolysis of the polymeric hyaluronan to the tetrasaccharide by the action of testicular hyaluronidase and separation of the product using CE. A UV detector operating at 200 nm was used. The X-ray contrast material, omnipaque, a propriety aqueous solution of iohexol was used as internal standard. A second peak in the electropherogram of synovial fluid was quantified. The variation in concentrations of these two components correlate with the arthritic disease state of a joint.

Arthritis, Rheumatoid↗
PubMed1989

Fourier transform infrared least-squares methods for the quantitative analysis of multicomponent mixtures of airborne vapors of industrial hygiene concern.

Air monitoring methods suitable for use in the workplace, though accurate for monitoring individual compounds or classes of compounds, cannot be used to monitor several compounds or classes of compounds simultaneously. In the past few years, Fourier transform infrared (FT-IR) spectroscopy has been investigated for use as a method for multicomponent quantitative analysis. This work focuses on quantitative analysis of six mixtures in ambient air. The concentration ranges of the two- to six-component mixtures are from 50 ppm to 100 ppb. The optimal least-squares fit (LSF) method selected, background reference file chosen, and quantitative peak windows picked were evaluated in this effort. The quantitative results of six mixtures were accurate at the 50, 10, and 1 ppm levels. There were some components for which the analysis was also accurate at the 0.1 ppm level. The data indicate that the LSF program could be used to quantify strongly overlapping multicomponent mixtures. The results support the conclusion that the FT-IR spectrometer is appropriate for the direct quantification of multicomponent mixtures of many airborne gases and vapors of industrial hygiene concern.

Air Pollutants, Occupational↗
PubMed1990

Quantitative analysis of enzyme-altered foci in rat hepatocarcinogenesis experiments--I. Single agent regimen.

Considerable recent attention has focused on the quantitative analysis of enzyme-altered foci in rodent hepatocarcinogenesis experiments. These foci are believed to represent clones of premalignant cells. A method is presented for the quantitative analysis of these foci that takes into account both the total number of focal transections observed in each liver cross-section and the size distribution of these transections. The method, which has a natural interpretation within the framework of a two-mutation model for carcinogenesis, yields estimates of rates of initiation and of growth rates of enzyme-altered foci as functions of dose of the agent under consideration. Definitions of initiation and promotion potencies are proposed. The method is illustrated by application to an experiment in which rats were administered N-nitrosomorpholine at various concentrations in their drinking water.

Adenosine Triphosphatases↗
PubMed2001

Quantitative analysis of detailed lignin monomer composition by pyrolysis-gas chromatography combined with preliminary acetylation of the samples.

Detailed quantitative analysis of lignin monomer composition comprising p-coumaryl, coniferyl, and sinapyl alcohol and p-coumaraldehyde, coniferaldehyde, and sinapaldehyde in plant has not been studied from every point mainly because of artifact formation during the lignin isolation procedure, partial loss of the lignin components inherent in the chemical degradative methods, and difficulty in the explanation of the complex spectra generally observed for the lignin components. Here we propose a new method to quantify lignin monomer composition in detail by pyrolysis-gas chromatography (Py-GC) using acetylated lignin samples. The lignin acetylation procedure would contribute to prevent secondary formation of cinnamaldehydes from the corresponding alcohol forms during pyrolysis, which are otherwise unavoidable in conventional Py-GC process to some extent. On the basis of the characteristic peaks on the pyrograms of the acetylated sample, lignin monomer compositions in various dehydrogenative polymers (DHP) as lignin model compounds were determined, taking even minor components such as cinnamaldehydes into consideration. The observed compositions by Py-GC were in good agreement with the supplied lignin monomer contents on DHP synthesis. The new Py-GC method combined with sample preacetylation allowed us an accurate quantitative analysis of detailed lignin monomer composition using a microgram order of extractive-free plant samples.

Acetylation↗
PubMed2003

[Quantitative analysis of mixed hematopoietic chimersim based short tandem repeats loci after nonmyeloablative stem cell transplantation].

OBJECTIVE: To establish a method for quantitative analysis of mixed hematopoietic chimerism (MC) based on STR loci. METHODS: Using STR technique combined with PCR, we analyzed the peripheral blood samples collected from 3 nonmyeloablative stem cell transplantation recipients every 15 days after transplantation. RESULTS: The quantitative results coincided with the qualitative results of DNA electrophoresis and with the clinical outcomes. When the result of electrophoresis showed only donor's allele type we could still find out the recipient's specific allele. CONCLUSION: The quantitative analysis using STR-PCR can detect more subtle changes in the evidence of engraftment. It is a more efficient method for detect the hematopoietic chimerism post transplantation.

Chimera↗
PubMed2001

Quantitative analysis of crystalline pharmaceuticals in powders and tablets by a pattern-fitting procedure using X-ray powder diffraction data.

A pattern-fitting procedure for quantitative analysis of crystalline pharmaceuticals in solid dosage forms using X-ray powder diffraction data is described. This method is based on a procedure for pattern-fitting in crystal structure refinement, and observed X-ray scattering intensities were fitted to analytical expressions including some fitting parameters, i.e. scale factor, peak positions, peak widths and degree of preferred orientation of the crystallites. All fitting parameters were optimized by the non-linear least-squares procedure. Then the weight fraction of each component was determined from the optimized scale factors. In the present study, well-crystallized binary systems, zinc oxide-zinc sulfide (ZnO-ZnS) and salicylic acid-benzoic acid (SA-BA), were used as the samples. In analysis of the ZnO-ZnS system, the weight fraction of ZnO or ZnS could be determined quantitatively in the range of 5-95% in the case of both powders and tablets. In analysis of the SA-BA systems, the weight fraction of SA or BA could be determined quantitatively in the range of 20-80% in the case of both powders and tablets. Quantitative analysis applying this pattern-fitting procedure showed better reproducibility than other X-ray methods based on the linear or integral intensities of particular diffraction peaks. Analysis using this pattern-fitting procedure also has the advantage that the preferred orientation of the crystallites in solid dosage forms can be also determined in the course of quantitative analysis.

Benzoic Acid↗
PubMed1988

A new method for the quantitative analysis of sleep spindles during continuous overnight EEG recordings.

Sleep spindles are one of the most characteristic EEG transients of sleep. Quantitative analysis of sleep spindles may be of value in the study of involuntary movement disorders, depression, and sleep disorders, but this is difficult to perform manually. Phase-locked loop based devices have previously been used to analyse preselected periods of artefact-free non-REM sleep. We have developed a device of this type that provides reliable quantitative analysis of sleep spindles during continuous overnight EEG recordings. The number of sleep spindles detected by the device during overnight recordings correlated well with the mean of two independent human observers and measurements of the amplitude and duration of individual sleep spindles were similar to those obtained by visual analysis. The general applicability of the device was demonstrated by studying 61 patients with a range of neurological disorders.

Electroencephalography↗
PubMed2003

Quantitative analysis of dobutamine-atropine stress echocardiography.

AIMS: To investigate the usefulness of fractional area change of entire left ventricular areas obtained from apical views for quantitative analysis of dobutamine-atropine stress echocardiography in the presence of mild to moderately reduced left ventricular function and abnormal intra-thoracic heart motion after coronary artery bypass surgery. METHODS AND RESULTS: Stress echocardiograms from 38 echogenic patients before and 3 months after bypass surgery and from 44 echogenic healthy subjects were analysed. In successfully revascularized patients the fractional area change at peak stress was correlated to the baseline left ventricular ejection fraction (r=0.54, P<0.01), whereas the increase from baseline to peak stress was constant over a wide range of baseline ejection fractions. With respect to identifying the pre-revascularization examination as diseased, the area under the receiver operator characteristics curve based on Delta fractional area change from baseline to peak stress was 0.78 (95% CI 0.55-1.00) indicating moderate accuracy comparable with the results obtained with conventional analysis. CONCLUSION: Fractional area change of entire left ventricular cavity areas is a useful parameter for quantitative analysis of dobutamine-atropine stress echocardiography. The diagnostic properties of the parameter are not offset by moderate reduction in left ventricular function or by surgery-induced abnormal intra-thoracic heart motion.

Adrenergic beta-Agonists↗
PubMed1984

Quantitative analysis of triglyceride species of vegetable oils by high performance liquid chromatography via a flame ionization detector.

A method for the quantitative analysis of triglyceride species composition of vegetable oils by reversed-phase high performance liquid chromatography (RP-HPLC) via a flame ionization detector (FID) is described. Triglycerides are separated into molecular species via Zorbax chemically bonded octadecylsilane (ODS) columns using gradient elution with methylene chloride in acetonitrile. Identification of species is made by matching the retention times of the peaks in the chromatogram with the order of elution of all of the species that could be present in the sample on the basis of a random distribution of the fatty acids and comparison of experimental and calculated theoretical carbon numbers (TCN). Quantitative analysis is based on a direct proportionality of peak areas. Differences in the response of individual species were small and did not dictate the use of response factors. The method is applied to cocoa butter before and after randomization, soybean oil and pure olive oil.

Chromatography, High Pressure Liquid↗
PubMed1984

[Quantitative analysis of exercise 201Tl myocardial emission CT in patients with coronary artery disease].

The clinical usefulness of quantitative analysis of exercise thallium-201 myocardial emission computed tomography (ECT) was evaluated in coronary artery disease (CAD). The subjects consisted of 20 CAD patients and five normal controls. All CAD patients underwent coronary angiography. Tomographic thallium-201 myocardial imaging was performed with a rotating gamma camera, and long-axial and short-axial myocardial images of the left ventricle were reconstructed. The tomographic images were interpreted quantitatively using circumferential profile analysis. Based on features of regional myocardial thallium-201 kinetics, two types of abnormalities were studied: diminished initial distribution (stress defect) and slow washout of thallium-201, as evidenced by patients' initial thallium-201 uptake and 3-hour washout rate profiles which fell below the normal limits, respectively. Two diagnostic criteria including the stress defect and a combination of the stress defect and slow washout were used to detect coronary artery lesions of significance (greater than or equal to 75% luminal narrowing). The ischemic volumes were also evaluated by quantitative analysis using thallium-201 ECT. The diagnostic accuracy of the stress defect criterion was 95% for left anterior descending, 90% for right, and 70% for left circumflex coronary artery lesions. The combined criteria of the stress defect and slow washout increased detection sensitivity with a moderate loss of specificity for identifying individual coronary artery lesion. A relatively high diagnostic accuracy was obtained using the stress defect criterion for multiple vessel disease (75%). Ischemic myocardial volume was significantly larger in triple vessel than in single vessel disease (p less than 0.05) using the combined criteria.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗