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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↗
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↗
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↗
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↗
PubMed1995

Quantitative analysis of HIV-1 RNA in plasma preparations.

HIV-1 RNA extraction methodology, stability and cellular location in plasma were studied by quantitative analysis using reverse transcriptase (RT) and polymerase chain reaction (PCR). HIV-1 RNA as intact virus was stable in plasma at room temperature for at least for 24 h, or stable in RNAzol (Tel-Test, Inc. Texas) at -70 degrees C for at least 6 months. The HIV-1 RNA PCR signal did not decline significantly after freezing and thawing of the virus in plasma or in RNAzol. To assess the effect of plasma constituents from different individuals upon quantitative PCR, identical copy members of HIV LAI were spiked into plasma from 9 different, normal individuals. PCR detection of HIV-1 RNA did not show any significant variation in quantitative signals. Additionally, platelet-rich plasma from three seropositive subjects was fractionated into a platelet-free plasma fraction and a platelet pellet fraction. The quantitative analysis of HIV-1 RNA in these fractions, and in the corresponding peripheral blood lymphocytes (PBLs) from each patient, demonstrated that the majority of the HIV-1 RNA was distributed in the plasma, and the HIV-1 RNA in the plasma of these patients seemed not to be strongly platelet associated.

Blood Platelets↗
PubMed1988

A quantitative analysis of mitochondria during fetal mouse oogenesis.

A quantitative analysis of mitochondrial populations during the meiotic prophase of mouse oogenesis was carried out. The mean absolute area occupied by mitochondria and the mean number of mitochondria per cell increases in a linear fashion from pachytene through dictyate. The mean area occupied by mitochondria increases at pachytene and thereafter. Both small and large aggregations of mitochondria are seen, particularly during the later stages of prophase. Vacuolated mitochondria are present from preleptotene through pachytene. Mitochondria show major dynamic changes throughout fetal mouse oogenesis, which may suggest significant functional activities yet to be elucidated.

Animals↗
PubMed1988

Turner's syndrome: a qualitative and quantitative analysis of EEG background activity.

A qualitative and quantitative analysis was performed on the EEG background activity in 62 Danish girls and women with Turner's syndrome (30 with karyotype 45,X and 32 with other karyotypes) whose ages ranged from 6 to 47 years (87% were aged 15 years or more) and age-matched controls. The pooled data and a case-control study showed characteristic features in Turner subjects, including: (1) more rapid frequency, larger amplitude and lower amount of alpha waves, (2) higher amount of theta waves, (3) larger amplitude and higher amount of delta waves and (4) larger amplitude and higher amount of beta waves than in controls. These findings in Turner subjects were more pronounced in the left hemisphere, and more typical, except for the amplitude in alpha waves, in Turner subjects with 45,X than in those with other karyotypes. The effects of advancing age on the EEG background activity observed in controls--including more rapid frequency, decreased amplitude and amount of alpha waves, increased amount of theta and delta waves, and increased amount of beta waves, particularly after 35 years of age--were found in some Turner subjects. Hemispheric differences with higher activity (i.e. more rapid frequency, larger amplitude and higher amount of alpha waves, particularly at Fp1 and F3, and, inversely, lower amount of theta or delta waves) at P3, T3, T5 and O2 than at the opposite side were found in many Turner subjects. However, these findings were not specific for Turner subjects, since the same hemispheric differences were also observed much more markedly in controls. These topographic distributions with hemispheric differences did not provide evidence for hypofunction in the temporo-parieto-occipital tertiary area of the right hemisphere in Turner subjects, though this had been expected on the basis of neuropsychological examinations. Our findings, including transiently appearing brain hypofunction at the parietal, temporal and occipital areas, most often in the right hemisphere, indicate a relationship between the chromosomal constitution 45,X and EEG background activity. They suggest the presence of functional brain disturbance in the thalamus and in the ascending reticular activating system, which tends to disturb the thalamo-cortical circuit. Further studies, including topographic and sequential power spectrum analysis of EEG background activity, 24-h continuous EEG recording, blood flow studies (positron computerized tomography) and neuropathological examination, may be needed.

Adolescent↗
PubMed1996

DNA methylation of the X chromosomes of the human female: an in situ semi-quantitative analysis.

We present an in situ semi-quantitative analysis of the global DNA methylation of the X chromosomes of the human female using antibodies raised against 5-methylcytosine. The antibodies were revealed by immunofluorescence. Images were recorded by a CCD camera and the difference in intensity of fluorescence between active (early replicating) and inactive (late-replicating) X chromosomes was measured. Global hypomethylation of the late-replicating X chromosomal DNA was observed in three cases of fibroblast primary cultures that were characterized by numerical and structural aberrations of the X chromosomes [46,X,ter rea(X;X), 48,XXXX and 46, X,t(X;15)]. In these cases, the difference between early and late-replicating X chromosomes was significantly greater than the intra-metaphasic variations, measured for a pair of autosomes, that result from experimental procedures. In cells with normal karyotypes, the differences between the two X chromosomes were in the range of experimental variation. These results demonstrated that late replication and facultative heterochromatinization of the inactive X are two processes that are not related to global hypermethylation of the DNA.

5-Methylcytosine↗
PubMed1994

A quantitative analysis of the glomeruli in focal segmental glomerulosclerosis.

Quantitative analysis of the glomerular area, mesangial matrix and mesangial cells was performed using renal biopsy specimens from 22 children with focal segmental glomerulosclerosis (FSGS) and 20 with minimal change nephrotic syndrome (MCNS). Non-sclerotic glomeruli were examined. All children in both groups showed nephrotic syndrome at the time of biopsy. Children with benign haematuria were examined as controls. Glomerular area increased with age in the FSGS, MCNS and control groups. The glomerular area was significantly greater in FSGS (1.5 +/- 0.4 x 10(4) microns 2) than in MCNS (1.2 +/- 0.2 x 10(4) microns 2) or in controls (1.2 +/- 0.3 x 10(4) microns 2) (P < 0.05). Mesangial matrix was increased with age in the three groups. The mesangial matrix was significantly increased in FSGS (28.3 +/- 4.0%; mesangial matrix area/glomerular area) compared with MCNS (24.9 +/- 4.1%) and controls (23.0 +/- 3.0%) (P < 0.01). These findings suggest that both glomerular hypertrophy and mesangial matrix increase in non-sclerotic glomeruli in FSGS may lead to glomerular sclerosis.

Adolescent↗
PubMed1989

Quantitative analysis of outward rectifying K+ channel currents in guard cell protoplasts from Vicia faba.

A quantitative analysis of the time and voltage dependence of outward-rectifying K+ currents (IK+, out) in guard cells from Vicia faba is described using the whole-cell patch-clamp technique. After step depolarizations from -75 mV to potentials positive to -40 mV, time-dependent outward currents were produced, which have recently been identified as K+ channel currents. This K+ current was characterized according to its time dependence and its steady-state activation. IK+, out could be described in terms of a Hodgkin-Huxley type conductance. Activation of the current in time was sigmoid and was well fitted by raising the activation variable to the second power. Deactivating tail currents were single exponentials, which suggests that only one conductance underlies this slow outward K+ current. Rates of channel closing were strongly dependent on the membrane potential, while rates of channel opening showed only limited voltage dependence leading to a highly asymmetric voltage dependence for channel closing and opening. The presented analysis provides a quantitative basis for the understanding of IK+, out channel gating and IK+, out channel functions in plant cells.

Action Potentials↗