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PubMed1983

The course and prognosis of manic-depressive psychosis: a quantitative analysis of episodes and intervals.

A quantitative analysis of episodes and symptom-free intervals in the course of manic-depressive psychosis was attempted. 1,066 patients who visited Tohoku University Hospital between 1955 and 1965 were investigated by a mail questionnaire and subsequent review of records in their care hospitals. There was no difference between the reply group and non-reply group in terms of demographic status. About 6.2% of patients were chronically ill. Eighteen percent of patients were dead at the time of study. The number of episodes was about three in depression and about seven in bipolar type during twelve years of observation. The length of symptom-free interval between episodes was about five years in depression and two years in bipolar type. There was no difference in the number of episodes or in the length of interval between 1955-1959 group and 1960-1965 group. The change of length was not confirmed between early and late intervals.

Bipolar Disorder↗
PubMed1991

[Quantitative analysis of signal-averaged electrocardiograms].

Quantitative analysis of the high frequency components of the terminal portion of the high-resolution surface QRS was performed in 119 normal subjects (N), 62 patients with ventricular tachycardia (VT) including 20 patients with sustained VT or VF (VTs/VF) and in 565 ischemic and nonischemic cardiac patients (NO-VT). High-resolution surface ECG (SAECG) was obtained during sinus rhythm with noise level below 0.4 microV by ART-1200EPX. The vector magnitude of the filtered and signal-averaged standard bipolar orthogonal leads X, Y, Z (V = square root of X2 + Y2 + Z2) were used for analysis. Total duration of the QRS (QRST), the duration of the low amplitude (40 microV) signals in the terminal portion of the QRS (D40) and the amplitude of the signals in the last 40 ms (V40) were measured at filter settings of both 25Hz and 40Hz by the computer. Specific values for each of the indices were identified at both 25Hz and 40Hz filterings, which could separate N as well as NO-VT from VTs/VF. They were greater than or equal to 120 ms for QRST, greater than or equal to 34 ms for D40 and less than or equal to 25 microV for V40 at 25Hz, greater than or equal to 120 ms for QRST, greater than or equal to 39 ms for D40 and less than or equal to 20 microV for V40 at 40 Hz filtering.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Quantitative analysis of individual renal function using 99mTc-DMSA scintigram--comparison with 131I-OIH renogram].

99mTc-2,3-di-mercapto-succinic acid (DMSA) is able to be used for the quantitative analysis of individual renal function by calculating the uptake ratio. The purpose of this study is to assess the clinical feasibility of DMSA uptake ratio as compared with 131I-ortho-iodo-hippuran (OIH) renogram pattern. Two hundred eleven cases (191 patients, 1 to 87 years old) with renal disorders and 4 normal volunteers (27.8 +/- 2.4 years old) were studied. Just prior to the DMSA study in the same day, OIH renogram was carried out. They were divided into 6 types by OIH renogram patterns. In 24 cases of normal renogram pattern and normal blood data who were defined as the normal group and 4 normal volunteers, DMSA uptake ratio showed negative correlation with increasing age (r = 0.61, p < 0.05). Patients of the severe impaired functioning and the non functioning patterns showed significantly decreased DMSA uptake ratios as compared with the normal pattern. There was also a significant difference in DMSA uptake between impaired functioning patterns. Compensative hemi-hypertrophy kidneys showed significantly higher DMSA uptake ratios than those of atrophic kidneys. The possibility of the quantitative analysis of the functional compensation was presumed. In conclusion, quantitative analysis of individual renal function using DMSA uptake ratio is considered to be useful to evaluate the renal functional reserve.

Adolescent↗
PubMed1993

[Quantitative analysis of right ventricular overloading by 201Tl myocardial SPECT].

Clinical usefulness of quantitative analysis of right ventricular overloading was evaluated by 201Tl myocardial SPECT in comparison with cardiac catheterization and MRI. Seventy-four MBq of 201TlCl was intravenous injected and 201Tl myocardial SPECT was performed on 40 patients (mean age: 61.0 +/- 11.8) with right ventricular overloading. Regions of interest (ROI) were selected on right and left ventricular walls in a midventricular short axis image of SPECT and uptake of each ROI were counted. The right ventricle (RV)/left ventricle (LV) 201Tl uptake ratio (R/L-Tl) was calculated. Wall thickness of RV and LV were measured on MRI and the RV/LV wall thickness ratio (R/L-WT) was calculated. RV and LV pressure were recorded in cardiac catheterization, and the RV/LV systolic pressure ratio (R/L-P) was calculated. There was significant positive correlation (Y = 0.73X + 0.19, r = 0.71, p < 0.001) between R/L-Tl and R/L-WT. R/L-Tl was positively correlated with R/L-P in patients with pressure overload (Y = 1.14X - 0.049, r = 0.85, p < 0.001) and in patients with volume overload (Y = 0.51X + 0.023, r = 0.88, p < 0.001) and the slope of the regression line in patients with pressure overload was significantly steeper than that in patients with volume overload (p < 0.001). In conclusion, quantitative analysis of right ventricular overload by 201Tl myocardial SPECT is useful to estimate RV/LV wall thickness ratio and pressure ratio.

Adult↗
PubMed1991

Availability and limitations of thallium-201 myocardial SPECT quantitative analysis: assessment as daily routine procedure for ischemic heart disease.

To determine the availability and limitations of the detection of ischemic lesions by stress thallium-201 myocardial SPECT as the daily routine procedure, we compared and evaluated the detectability of the quantitative analysis (%uptake and washout rate (WR)) and visual evaluation in 104 patients with effort angina and 17 normal subjects. Visual evaluation combined with WR analysis resulted in significantly higher sensitivity (88.0%) but lower specificity (60.2%) than the other methods. The sensitivity by visual evaluation was quite low in multivessel disease (MVD), and in the regions supplied by mild coronary stenosis or by the left circumflex artery. These were markedly improved by combining visual evaluation and WR analysis, but sensitivity in the MVD group was unsatisfactory even with this analytic method in comparison with the single vessel disease group. One of the causes of low sensitivity in the MVD group might be the "true negative": No induction of the ischemia in the regions of milder stenosis, or the regions supplied by the collateral coronary flow. We therefore conclude that the combination of visual evaluation as a qualitative analysis and WR analysis as a quantitative analysis, is the most useful daily routine procedure as a screening test for detecting ischemia.

Aged↗
PubMed1987

[A method for the quantitative analysis of steroid hormones by HPLC/RIA].

To solve the problem of cross-reaction in immunoassay and determine various steroid hormones simultaneously in a small amount of sample, a method for the quantitative analysis of steroid hormones was developed. This method is a combination of high-performance liquid chromatography (HPLC) and radioimmunoassay (RIA). The purpose of the study is the comprehensive analysis of steroid hormones profiles in normal subjects and adreno-cortical diseases. One hundred microliters of plasma was extracted by ether and the ether layer was evaporated. The residue was redissolved and separated by HPLC. Then fractions of steroid hormones were taken and determined by RIA. In this study, cortisol (F), androstenedione (A), 17 alpha-hydroxyprogesterone (17-OHP), testosterone (T), progesterone (P), estrone (E1) and estradiol (E2) were analyzed in normal adults, congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency and Cushing's syndrome. Results in normal adults were similar with those had been previously reported. In CAH, F was remarkably low and 17-OHP, A, T and P were remarkably high before treatment. During treatment some cases showed that 17-OHP, A, T and P were high, and 17-OHP and P tended to be within normal range, if F had been kept higher than about 20 micrograms/dl. In the analysis of Cushing's syndrome before treatment, there were definite differences between adenoma and hyperplasia. A, 17-OHP, T, E1 and E2 were higher in hyperplasia than those in adenoma. It is suggested that it is possible to diagnose the type of Cushing's syndrome with a small amount of plasma using this method. As a mass screening method of CAH at present, 17-OHP in dried blood on filter paper is determined, therefore the quantitative analysis of 17-OHP in dried blood on filter paper (9 mm disc) was attempted. The quantitative analysis proved to be possible, and it was considered to be applied as the secondary screening method of CAH by the use of dried blood on filter paper.

Adrenal Cortex Hormones↗
PubMed1990

Secondary structure of the ribosome binding site determines translational efficiency: a quantitative analysis.

We have quantitatively analyzed the relationship between translational efficiency and the mRNA secondary structure in the initiation region. The stability of a defined hairpin structure containing a ribosome binding site was varied over 12 kcal/mol (1 cal = 4.184 J) by site-directed mutagenesis and the effects on protein yields were analyzed in vivo. The results reveal a strict correlation between translational efficiency and the stability of the helix. An increase in its delta G0 of -1.4 kcal/mol (i.e., less than the difference between an A.U and a G.C pair) corresponds to the reduction by a factor of 10 in initiation rate. Accordingly, a single nucleotide substitution led to the decrease by a factor of 500 in expression because it turned a mismatch in the helix into a match. We find no evidence that exposure of only the Shine-Dalgarno region or the start codon preferentially favors recognition. Translational efficiency is strictly correlated with the fraction of mRNA molecules in which the ribosome binding site is unfolded, indicating that initiation is completely dependent on spontaneous unfolding of the entire initiation region. Ribosomes appear not to recognize nucleotides outside the Shine-Dalgarno region and the initiation codon.

Base Sequence↗
PubMed1987

Characterization of tissue and plasma glycosaminoglycans during experimental AA amyloidosis and acute inflammation. Qualitative and quantitative analysis.

Qualitative and quantitative methods were used to determine changes in glycosaminoglycans (GAGs) in the spleen and plasma during initial stages of experimental amyloidosis and acute inflammation. GAG deposition in the spleen during the early stages of amyloidosis consists of a 16-fold heparin and heparan sulfate increase. Though splenic weights do increase during protracted inflammation only minor changes arise in splenic GAGs in the absence of amyloid deposition. An overall increase in plasma GAGs, consisting of a 4.5-fold chondroitin-4-sulphate increase, occurred at the time of GAG deposition in the tissues (spleen, liver) and probably accounts for the minor GAG changes seen in the spleen during inflammation. The time course of splenic heparin/heparan sulfate increase during amyloid deposition coincides with the histochemical changes previously described. Plasma GAG changes follow a pattern similar to that of acute phase protein reactants. The results suggest that GAG metabolism, in particular heparin/heparan sulfate, are intimately involved in the process of AA amyloidogenesis.

Acute Disease↗
PubMed1986

Noninvasive identification of left main and triple vessel coronary artery disease: improved accuracy using quantitative analysis of regional myocardial stress distribution and washout of thallium-201.

The capabilities of visual and quantitative analysis of stress redistribution thallium-201 scintigrams, exercise electrocardiography and exercise blood pressure response were compared for correct identification of extensive coronary disease, defined as left main or triple vessel coronary artery disease, or both (50% or more luminal diameter coronary narrowing), in 105 consecutive patients with suspected coronary artery disease. Extensive disease was present in 56 patients and the remaining 49 had either less extensive coronary artery disease (n = 34) or normal coronary arteriograms (n = 15). Although exercise blood pressure response, exercise electrocardiography and visual thallium-201 analysis were highly specific (98, 88 and 96%, respectively), they were insensitive for identification of patients with extensive disease (14, 45 and 16%, respectively). Quantitative thallium-201 analysis significantly improved the sensitivity of visual thallium-201 analysis for identification of patients with extensive disease (from 16 to 63%, p less than 0.001) without a significant loss of specificity (96 versus 86%, p = NS). Eighteen (64%) of the 28 patients who were misclassified by visual analysis as having less extensive disease were correctly classified as having extensive disease by virtue of quantitative analysis of regional myocardial thallium-201 washout. When the results of quantitative thallium-201 analysis were combined with those of blood pressure and electrocardiographic response to exercise, the sensitivity and specificity for identification of patients with extensive disease was 86 and 76%, respectively, and the highest overall accuracy (0.82) was obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Automated selection of regions of interest for quantitative analysis of lung textures in digital chest radiographs.

In order to implement a computerized scheme for quantitative analysis of interstitial lung disease in chest radiographs in clinical situations, a fully automated method of selecting many square regions of interest (ROIs) in peripheral lung areas are developed. First, the peripheral lung regions are identified, based on the automated detection of lung apices, ribcage edges, and diaphragm. Then a large number of ROIs are selected sequentially by filling in the identified peripheral regions. Finally, those ROIs containing sharp edges are removed based on an edge gradient analysis, for which a gradient-weighted edge orientation histogram is employed. Approximately 200-400 ROIs were automatically selected for each case with this method. The evaluation of using ROC analysis indicated that the automated ROI selection method was effective in quantitative analysis of lung textures in digital chest radiographs.

Biophysical Phenomena↗
PubMed1995

Quantitative analysis of bandpass-filtered Fourier transform infrared interferograms.

The feasibility of performing quantitative analysis with short segments of bandpass-filtered Fourier transform infrared (FT-IR) interferograms is demonstrated. The protocol developed in this work addresses four limitations that hinder the use of FT-IR spectroscopy in nonlaboratory applications: (1) the need for a rugged, low-cost, and reliable spectrometer, (2) the lack of representative background spectra for use in acquiring absorbance spectra of the target analyte, (3) the presence of overlapping spectral bands that interfere with the analyte determination, and (4) the difficulty in obtaining useful information from data collected near the limit of detection. In this work, spectral information pertaining to a specific analyte band of interest is isolated directly from a short interferogram segment by the application of narrow-bandpass digital filters. When processed in this way, the filtered interferogram segments contain compound-specific information that can be utilized for quantitative analysis. Successful use of a univariate calibration procedure with filtered interferogram data of benzene and nitrobenzene of varying concentrations is demonstrated. Calibrations based on filtered interferogram segment magnitudes vs concentration yield models with values of R2 in excess of 99%. These results are obtained without the use of a separate background or reference interferogram. This interferogram-based analysis is shown to perform analogously to a conventional spectral-based analysis, with the interferogram method being more efficient in terms of data collection and computational requirements.

Benzene Derivatives↗
PubMed1975

Quantitative analysis of the carotid sphygmogram in atherosclerosis.

A study has been made, by means of quantitative analysis, of the changes in the CSG of 355 persons-131 healthy, 112 with ischemic heart disease and 112 with hypertension. The quantitative analysis includes: (1) coefficient of declination, pointing to the declivity of the anacrotic limb; (2) coefficient of propulsion, pointing to the time of formation of the maximum peak and (3) level of indentation, pointing to the height of the valve notch. These 3 indices regularly increase along with progressive induration of the arterial wall and serve as quantitative criteria for a more accurate differentiation of the separate types of CSG used in clinical practice.

Adolescent↗
PubMedDate not supplied

The quantitative analysis of inhalational anaesthetics in forensic samples by gas chromatography/mass spectrometry/selected ion monitoring.

The quantitative analysis of volatile anaesthetics for biomedical applications by means of gas chromatograph/mass spectrometry/selected ion monitoring (GC/MS/SIM) was studied. Xenon gas was selected as an internal standard for the assay by adding to a closed system, because of its stability and inactivity. In the assay of inhalational anaesthetics, isoflurane and nitrous oxide (laughing gas), in forensic samples (serum and cerebrospinal fluid), the calibration of the anaesthetic was linear from 0.12 to 12 nmol/mL in isoflurane and from 30 to 300 nmol/mL in nitrous oxide. Our results suggest that this new method is suitable for the quantitative analysis of inhalational anaesthetics in the biomedical field.

Anesthetics, Inhalation↗
PubMedDate not supplied

A quantitative analysis of the afferent innervation of the organ of corti in guinea pig.

A quantitative analysis of the afferent innervation of the organ of Corti was made on normal and vestibular nerve-sectioned guinea pigs. Section of the vestibular nerve at the internal auditory meatus provided an efficient means of eliminating the efferent innervation to the cochlea without significant loss of afferent fibres. Nerve counts on normal and de-efferented animals revealed that about 10-15 % of the cochlear afferent innervation supplies the outer hair cells. The remaining 85-90% of afferent fibres innervate the inner hair cells. As in cats, all tunnel spiral bundle fibres and upper tunnel crossing fibres were efferent to outer hair cells. Since unmyelinated fibres in the osseous spiral bundle were not counted, quantitative analysis of the efferent innervation to inner hair cells could not be made. However, a significant loss of myelinated fibres in the osseous spiral lamina after vestibular nerve section confirms that many myelinated efferent fibres are present in this region.

Animals↗
PubMed1983

[Qualitative and quantitative analysis of regional contraction disorders using levocardiograms].

In 74 patients with proven myocardial infarction (typical history and enzymes, diagnostic ECG, and stenosis of the vessel supplying the asynergic region of more than 75%) the results of qualitative analysis of left ventricular cineangiograms were compared to those of quantitative analysis using the radial axis method of Mathes. There was a significant difference in interpretation between the two methods if the physiological movements of the heart were not taken into account in the qualitative analysis. After correction for systolic anterior movement and downward movement of the aortic valve during systole, a mean accuracy of 92% resulted. The radial axis method discriminated well between normokinetic and asynergic wall segments. However, this method proved less useful for the detection of asynergies in the apical, anterobasal, and posterobasal regions. A radial axis angle of between 15 degrees and 20 degrees is considered to be optimal. The quantitative analysis seems to be particularly useful for the interpretation of borderline cases, and should be carried out routinely in addition to the qualitative analysis.

Adult↗
PubMed1994

Quantitative analysis of vibrational circular dichroism spectra of proteins. Problems and perspectives.

Experimental and computational aspects of the quantitative analysis of vibrational circular dichroism (VCD) of proteins are discussed. Experimentally, the effect of spectral resolution, sample concentration, cell selection and spectral normalization effects are considered. The influence of random intensity variations on the results of quantitative analysis of amide I' VCD are shown to be minor up to a 15% variation in spectral intensity. A computational algorithm, based on factor analysis of the spectra and multiple linear regression calculation of fractions of secondary structures (FC), was designed to analyse quantitatively the details of the VCD spectra-structure relationship. It also enabled the results of VCD measured independently for the amide I' and amide II regions to be combined. Our study is based primarily on the optimization of the calculation to predict FC values for proteins not included in the reference data set used for regression. The best prediction is obtained with the function using only part of the observable independent VCD spectral components. Inclusion of all components actually reduces the prediction accuracy of the analysis. Spectroscopic reasons for such behaviour and the consequences of the interdependence of the crystallographic FC values on the spectra-structure analysis are discussed. Finally, the possibility of utilizing VCD spectra to obtain quantitative structural information about the protein beyond the conventional secondary structure composition is explored. A matrix descriptor of super-secondary structure features for proteins is designed, and preliminary results for prediction of this descriptor from amide I' VCD spectra are presented. These latter calculations use a novel design of the back-propagation neural network.

Circular Dichroism↗
PubMed2001

A new method and software for quantitative analysis of continuous intracranial pressure recordings.

OBJECTIVE: A computer software utilising a new method for quantitative analysis of intracranial pressure (ICP), was developed to provide a more accurate analysis of continuously recorded ICP. Intracranial pressure curves were analysed by the software to explore the relationship between mean ICP and the presence of ICP elevations. METHODS: The Sensometrics Pressure Analyser (version 1.2) software provides a quantitative analysis of the ICP curve, presenting the ICP recordings as a matrix of numbers of ICP elevations of different levels (e.g. 20 or 30 or 40 mmHg) and durations (e.g. 0.5, 5 or 10 minutes). The number of ICP elevations may be standardised by calculating the number of elevations during for instance a 10 hour period. The computer software was used to retrospectively analyse the ICP curves in our first consecutive 127 patients undergoing continuous 24 hours ICP monitoring during the two-year period from February 1997 to December 1998. The indications for ICP monitoring were suspected hydrocephalus, craniosynostosis or shunt failure. RESULTS: Analysis of the ICP curves revealed a rather weak relationship between mean ICP and the number of apparently abnormal ICP elevations (that is elevations of 20 mmHg or above). Abnormal ICP elevations were present in a relatively high proportion of cases with a normal mean ICP below 10 mmHg, or a borderline mean ICP between 10 and 15 mmHg. In addition, the ICP data of two cases are presented suggesting that mean ICP may be an inaccurate measure of ICP. CONCLUSIONS: The results of analysing ICP curves by means of this method and software reveal that calculation of ICP elevations of different levels and durations may represent a more accurate description of the ICP curve than calculation of mean ICP. The method may enhance the clinical application of ICP monitoring.

Adolescent↗
PubMed1990

[Quantitative analysis of background activity using ambulatory EEG monitoring system].

We studied a possibility of the quantitative analysis of background activities using ambulatory EEG monitoring system (AEEG). (1) This recorder system had a stable frequency characteristics from 1.0 Hz to 20 Hz, in which range the background activities on EEG were organized, and also had a good lineality of amplitude until 150 microV. Therefore, this system had no hindrance in quantitative analysis of EEG background activities. (2) We selected the method of continuous spectrum array (CSA) to analyse the records using AEEG. The CSAs at awakening, light sleep and deep sleep respectively revealed the characteristic patterns of spectrum. And, in the long-term examination of CSA during sleep, the dynamic alternation of spectrum was well recognized depending on the change of sleep stages. This method was useful to the evaluation of sleep cycle as well as the judgement of consciousness level. The AGGE has many advantages compared with the other long-term EEG systems. Major advantages are as follows: 1) The patient can move freely with this equipment. 2) A whole day's record can be stored on a cassette. 3) The operative technique is easy. The clinical and research application of AEEG may be more expanded to combine with the various computer analysing methods.

Electrocardiography, Ambulatory↗