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PubMed1992

Quantitative analysis of pulmonary vascular disease in total anomalous pulmonary venous connection in sixty infants.

A quantitative analysis of small pulmonary arteries, pulmonary veins, and lymphatic vessels was conducted in autopsy cases of total anomalous pulmonary venous connection. The materials were obtained from 60 cases of total anomalous pulmonary venous connection without asplenia or pulmonary stenosis, ages ranging from 2 days to 19 months at the time of death (mean age 2.2 months). Pulmonary arterial pressure had been measured in 32 of these patients before death. Twenty cases of ventricular septal defect with pulmonary hypertension and 15 normal individuals were used as the control group. The mean thickness of the media of small pulmonary arteries and veins was 12.7 and 7.6 microns, respectively, in the total anomalous pulmonary venous connection cases, both values being significantly larger than those for normal and ventricular septal defect cases. No changes in thickness with aging were found. Medial thickness in the arteries and veins was greater in the cases of pulmonary venous obstruction than in those without such obstruction. The medial thickness of small pulmonary arteries in total anomalous pulmonary venous connection cases correlated with increased pulmonary arterial pressure. When the patients with the same pulmonary arterial pressure levels were compared, the medial thickness was always greater in those who had total anomalous pulmonary venous connection than in those who had ventricular septal defect. The medial thickness of pulmonary veins was also highly correlated with increased pulmonary arterial pressure in total anomalous pulmonary venous connection. The severity of the intimal lesions was milder in those who had total anomalous pulmonary venous connection than in those who had ventricular septal defect, suggesting the protective role of the thickened pulmonary arterial media against development of intimal lesions. Intimal fibrous thickening of pulmonary veins was not seen in the cases of ventricular septal defect, but it was present in 45% of the total anomalous pulmonary venous connection cases. Lymphangiectasia was characteristically present in 62% of the total anomalous pulmonary venous connection cases. Interstitial emphysema was often a complication of lymphangiectasia, and it led to eight postoperative deaths.

Age Factors↗

PubMed1985

Morpho-quantitative analysis of nuclear inclusions in periaqueductal grey matter neurons in the cat.

The morpho-quantitative analysis carried out in the neuronal population of the periaqueductal grey matter of the cat has shown that nuclear inclusions are mainly of the filamentous type and that they are distributed predominantly in the external region, i.e. in the part of the periaqueductal grey matter situated furthest from the cerebral aqueduct, where 30% of the cells contain nuclear inclusions. In the internal region, i.e. in the part nearest the subependymal zone, only 2% of the neurons have nuclear inclusions. The glia in the internal region is more abundant and surrounds each nerve cell body while in the external zone of the periaqueductal grey matter it is scanty and does not delimit the neuronal soma. This difference suggests that there may be a relationship between the incidence of nuclear inclusions and the neuron/glia ratio.

Animals↗

PubMed1998

Quantitative analysis of ceramide molecular species by high performance liquid chromatography.

A method was developed for quantitative analysis of molecular species of ceramide (N-acyl-sphingosine) and dihydroceramide (N-acyl sphinganine) by high performance liquid chromatography (HPLC). Various N-acyl chain-containing ceramides or dihydroceramides were semi-synthesized as standard materials and allowed to react with anthroyl cyanide, a fluorescent reagent. Anthroyl derivatives of ceramide and dihydroceramide containing C16, C18, C20, C22, and C24 saturated N-acyl chain could be completely separated to each molecular species by reversed-phase HPLC equipped with fluorescence detector, although some ceramide molecular species containing monoenoic acyl chain were eluted together with saturated dihydroceramide species. Ceramide molecular species could be quantified using N-heptadecanoyl or N-tricosanoyl sphingosine as an internal standard, and the lower detection limit was below 1 pmol. This method was applied to the analysis of sphingomyelin and free ceramide in U937 cells. The analysis of the ceramide obtained by hydrolysis of sphingomyelin of U937 cells revealed that the ceramide moiety was mainly composed of N-palmitoyl sphingosine, N-nervonoyl sphingosine, and N-lignoceroyl sphingosine, representing 50.0, 27.4, and 6.7% of sphingomyelin, respectively. The total free ceramide and dihydroceramide of U937 cells was determined to be 254 +/- 5 pmol/10(6) cells. Major molecular species of the free ceramide fraction were N-lignoceroyl, N-palmitoyl, and N-nerovonoyl sphingosine, representing 27.6%, 26.6%, and 13.6% of this fraction, respectively. Different distribution of free ceramide molecular species from sphingomyelin species may suggest that selective metabolism of molecular species occurs in the synthesis or degradation of sphingomyelin. These results indicate that the picomole level of molecular species of ceramide and dihydroceramide is successfully determined by fluorescence HPLC and that this newly developed method may be useful to reveal the metabolism and function of ceramide and related compounds in cultured cells.

Acylation↗

PubMed2002

Multivariate curve resolution of overlapping voltammetric peaks: quantitative analysis of binary and quaternary metal mixtures.

The application of multivariate curve resolution-alternating least squares (MCR-ALS) to the quantitative analysis of different metal ion mixtures using voltammetric data is described. The performance of MCR-ALS was evaluated in the resolution and quantitation of overlapped voltammetric peaks obtained in the analysis of binary and quaternary mixtures of Cd(II), In(III), Pb(II) and Tl(I) metal ions by anodic stripping voltammetry. Quality assessment of qualitative and quantitative determinations was evaluated considering the effects of different constraints and of initial estimations. MCR-ALS results were validated and compared with those obtained by applying other well-established multivariate calibration methods, such as partial least squares (PLS) and direct classical least squares (DCLS) methods.

Journal Article↗

PubMed1992

Morphological quantitative analysis of intracranial pressure waves in normal pressure hydrocephalus.

This work presents a prospective morphological and quantitative analysis of 43 intracranial pressure recordings performed on normal pressure hydrocephalic patients. This analysis led us to separate Lundberg's B waves into different subtypes and to refine the definition of the 'Plateau' wave. Two B wave subtypes named Great Symmetrical wave and Intermediate wave appeared correlated with the surgical improvement. In addition, the degree of post-operative improvement was correlated with the frequency of Intermediate wave. An extended quantitative classification of intracranial pressure waves is proposed that can be used alone to determine which patients should undergo a shunting procedure and which one should the most improve.

Aged↗

PubMed1991

Semi-quantitative analysis of SPECT with the iodinated fatty acid 15-(ortho-123I-phenyl)-pentadecanoic acid.

15-(ortho-123I-phenyl)-pentadecanoic acid (oPPA) in contrast to the para-isomer pPPA has a prolonged retention in the normal human myocardium. Following qualitative evaluation, a semi-quantitative analysis of oPPA-SPECT is presented in 52 patients (41 with coronary artery disease (CAD) and 11 normals). Data were compared to the results of coronary angiography (CAD patients). Up to 220 MBq 123I-labelled oPPA were injected intravenously after overnight fasting and bicycle exercise. Four minutes later SPECT acquisition (180 degrees technique) was started. In 15 patients a second dose of oPPA was injected 2.5 h later and the study was repeated under rest conditions. Compared to our qualitative analysis the semi-quantitative approach revealed a lower sensitivity of 76% for the detection of CAD (global, stenoses greater than 50%) (specificity was not analysed because the normal patients served as the control group for the calculation of normal values). Because the sensitivity does not exceed that of 201Tl-SPECT or MIBI-SPECT, oPPA is not recommended for the detection of CAD, but it may serve for the evaluation of myocardial viability in ischaemic regions.

Adult↗

PubMedDate not supplied

Qualitative and quantitative analysis of new amino acid derivatives of anticonvulsant activity.

Qualitative and quantitative methods for analysis of three new amino-acidic anticonvulsants of low neurotoxicity: pyrazole-3,5-dicarboxylic acid benzylamine (1), pyrazine-2-carboxylic acid benzylamine (2) and (R, S) N-acetyl-2-pyrrolidone-5-carboxylic acid benzylamide (3) have been developed. Qualitative analysis included characteristic reactions, chromatographic (TLC) investigations, IR and UV spectra interpretation and quantitative analysis involved spectrophotometric, chromatographic (HPLC) and acidimetric methods.

Amino Acids↗

PubMedDate not supplied

Qualitative and quantitative analysis of three amino acid derivatives of anticonvulsant activity.

Qualitative and quantitative methods of analysis of three new amino-acid derivatives potential anticonvulsants of low neurotoxicity: picolinic acid benzylamide (1), nicotinic acid benzylamide (2) and isonicotinic acid benzylamide (3) were developed. Qualitative analysis includes characteristic reactions, chromatographic (TLC) investigations, IR and UV spectra interpretation. The quantitative analysis involves spectophotometric, chromatographic (HPLC) and acidimetric methods.

Anticonvulsants↗

PubMed1999

Quantitative analysis of immunofluorescent signals for dystrophin, beta-dystroglycan and myosin skeletal muscle by epifluorescence microscopy.

Quantitative analysis of signal intensities in immunostained sections has been performed in only a few studies owing to difficulties with quantifying amounts of antigen present. We determined correlations between fluorescent signal intensities and amounts of antigen in muscle cryosections by altering section thickness from 4 to 10 microm. Fluorescent signals of dystrophin. beta-dystroglycan and myosin were detected with monoclonal and/or polyclonal primary antibodies using routine procedures. Confocal laser microscopy demonstrated that these signals were distributed uniformly along the z-axis suggesting that the antibodies permeated well through the sections. Epifluorescence microscopy with microfluorometry demonstrated a positive correlation between the optical density of signals and section thickness. These findings suggest that immunofluorescent signals can be quantitated by epifluorescence microscopy.

Adult↗

PubMed2004

[Application of sequential and quantitative analysis of donor chimerism in donor lymphocyte infusion].

In order to study the value of sequential and quantitative analysis of chimerism in determination of optional time of donor lymphocyte infusion (DLI) and prediction of efficacy of DLI, six patients with leukemias who relapsed or failed of engraftment were treated with DLI. Serial and quantitative analyses of donor chimerism (DC) both prior to and following DLI were performed by multiplex PCR amplification of STR markers (STR-PCR) and capillary electrophoresis with fluorescence detection. The results showed that at the time of relapse or graft rejection, STR-PCR indicated the decreasing donor chimerism in all six patients, at levels ranging from 27.3% to 85.7%. The declining value of DC (<90%) was detected in four patients at 26 days before relapse or graft rejection diagnosed clinically. Therefore the decrease of value of DC can be identified the high risk of relapse or graft failure and can be used to guide DLI implementation at early stage. In this study the clinical response were seen in two patients, the value of DC in these patients increased with convertion to a predominant donor profile (>90%) or converted to stable FDC shortly after DLI, while in the patients without clinical response, the level of DC decreased persistently or declined after transient increase. Three patients without response received second DLI. It is concluded that the monitoring of chimerism is proved to be a valuable to determine the optional time point of DLI and to early evaluate the efficacy of DLI. Furthermore, it can present a rational basis for treatment of intensification in the patients who did not respond to first-line DLI treatment.

Adolescent↗

PubMed2005

Quantitative analysis of both protein expression and serine / threonine post-translational modifications through stable isotope labeling with dithiothreitol.

While phosphorylation and O-GlcNAc (cytoplasmic and nuclear glycosylation) are linked to normal and pathological changes in cell states, these post-translational modifications have been difficult to analyze in proteomic studies. We describe advances in beta-elimination / Michael addition-based approaches which allow for mass spectrometry-based identification and comparative quantification of O-phosphate or O-GlcNAc-modified peptides, as well as cysteine-containing peptides for expression analysis. The method (BEMAD) involves differential isotopic labeling through Michael addition with normal dithiothreitol (DTT) (d0) or deuterated DTT (d6), and enrichment of these peptides by thiol chromatography. BEMAD was comparable to isotope-coded affinity tags (ICAT; a commercially available differential isotopic quantification technique) in protein expression analysis, but also provided the identity and relative amounts of both O-phosphorylation and O-GlcNAc modification sites. Specificity of O-phosphate vs. O-GlcNAc mapping is achieved through coupling enzymatic dephosphorylation or O-GlcNAc hydrolysis with differential isotopic labeling. Blocking of cysteine labeling by prior oxidation of a cytosolic lysate from mouse brain allowed specific targeting of serine / threonine post-translational modifications as demonstrated through identification of 21 phosphorylation sites (5 previously reported) in a single mass spectrometry analysis. These results demonstate BEMAD is suitable for large-scale quantitative analysis of both protein expression and serine / threonine post-translational modifications.

Animals↗

PubMed2004

Qualitative and quantitative analysis of small amine molecules by MALDI-TOF mass spectrometry through charge derivatization.

A pair of isotopically coded light and heavy reagents, tris(2,4,6-trimethoxyphenyl)phosphonium acetic acid N-hydroxysuccinimide esters (1 and 2) were synthesized and used to derivatize low molecular weight (<500 Da) molecules containing primary or secondary amine functional groups for MALDI-TOF MS analysis. The light and heavy reagents added a 573 and 600 Da positively charged tag to each analyte, respectively. In the presence of 10 times excess of tag reagents, the coupling reactions reached near completion within 10 min. The derivatization greatly facilitated MALDI analysis of small molecules and significantly improved the sensitivity of analysis, allowing a limit of detection in the low femtomole range. Additionally, the reaction mixtures were directly analyzed by MALDI without sample cleanup. The quantification of small molecules by MALDI-TOF MS was successfully achieved by analysis of isotopically coded light and heavy derivatives. MALDI-TOF quantitative analysis of a mixture of antibiotics yielded calibration curves in the concentration range from 0.3 to 30 pmol/microL with r2 values greater than 0.9995.

Amines↗

PubMed2005

Quantitative analysis of surface EMG activity of cranial and leg muscles across sleep stages in human.

OBJECTIVE: The aim of this study was to make a quantitative analysis of the changes in cranial and limb muscle activity from wakefulness to light and deep sleep stages and during rapid eye movement (REM) sleep of normal subjects. METHODS: Polysomnographic recordings were made of the sleep of 9 healthy human subjects, including electromyograms of the suprahyoid, temporalis and masseter cranial muscles and the anterior tibialis limb muscle. Quantitative assessments of EMG activity were carried out with root mean square (RMS) and frequency-spectral analysis (FSA) methods. RESULTS: From wakefulness to sleep, a significant reduction (-25.2 to -71.2%; P < 0.01) was observed in EMG activity (for both RMS and FSA) of the 3 cranial muscles using both methods of analysis. The EMG activity of suprahyoid muscle further decreased from non-REM to REM sleep (-17.8 to -43.0%; P < 0.01). In contrast, the EMG activity of the anterior tibialis muscle was only slightly reduced across sleep stages and did not further reduce during REM sleep. During REM sleep, all the 4 muscles maintained minimal activity. CONCLUSIONS: The maintenance of muscle activity during REM sleep suggests that a minimal level of activity is required to preserve physiological functions (e.g. airway patency, posture) related to homeostasis and bodily protection. SIGNIFICANCE: This study suggests that quantitative sleep EMG analysis is important for understanding the mechanisms of sleep-related movement disorders or when objective assessment of changes in EMG activity are needed for diagnostic purposes or for the assessment of drug efficiency.

Adult↗

PubMed1995

Quantitative analysis of trabecular microstructure by 400 MHz nuclear magnetic resonance imaging.

A new approach for the quantitative analysis of trabecular microstructure, based on high-field proton nuclear magnetic resonance (NMR) imaging, is presented. NMR is ideal because it provides high contrast between the marrow proton signal and the bone, which appears with background intensity. Images from 1 cm3 defatted specimens of trabecular bone, suspended in water doped with 1 mM Gd(DTPA) to shorten T1 to about 300 ms, can be obtained at a resolution on the order of 30-50 microns and slice thickness of 150 microns, in 10 minutes at 400 MHz proton frequency. Digital image processing algorithms were designed and evaluated for the measurement of bone area fraction, perimeter length, mean trabecular thickness, and separation. Bone area fraction derived from the NMR images was found to be in excellent agreement with bone volume fraction measured independently (slope = 0.96, r2 = 0.924, p < 0.0001). Errors in the mean trabecular thickness and separation were < 6%. The effects of finite imaging slice thickness and signal-to-noise ratio (SNR) were also evaluated. The data suggest a resolution of 50 x 50 x 200 microns 3 and an SNR on the order of 10 to provide safe margins for precise and accurate structural analysis by means of the algorithms presented in this paper. The method allows simultaneous measurement at multiple locations within the specimen volume without the need for physical sectioning.

Algorithms↗

PubMed1977

Quantitative analysis of C-bands based on optical density profiles in human chromosomes.

A method of quantitative analysis of C segments in human chromosomes 1, 9, and 16 based on longitudinal densitometry has been developed. The way of fitting apparatus data to visual estimates is represented. Density curve parameters not dependent on stain intensity were used. The general C band length error is approx. 0.05 micrometer. Heteromorphic chromosome 16 pairs have been investigated with this method. A significant difference (about 0.18 micrometer) between C bands of the homologues has been detected in chromosome 16. It has been calculated that C bands can be distinquished if the mean difference between the length of the homologues is more than 15%.

Chromosomes, Human↗

PubMed1994

Quantitative analysis of Lewis antigens on erythrocytes by flow cytometry.

We have developed a method for the quantitative analysis of Lewis antigens on human red blood cells (RBC) using immunofluorescence labeling and flow cytometry. Initially, Lewis a and Lewis b (Le(a) and Le(b)) antigens were labeled with monoclonal anti-Le(a) or anti-Le(b) antibodies followed by labeling with the fluorescein isothiocyanate (FITC)-conjugated second antibody. This method was not sensitive enough to identify the Lewis antigens on RBC, although the FITC method is very commonly used for antigens on white blood cells. Next, we selected the enhanced labeling technique using the avidin-biotin procedure. Biotinylated anti-mouse IgM was used for the second label and the reaction with R-phycoerythrin (RPE)-conjugated streptavidin followed to produce the fluorescence. The method was found to be effective for our objectives. From the results analyzed by the enhanced labeling technique, differences were not found in either the levels of the antigen-positive percentage and the peak mean channel of Le(a) antigens on RBC in the groups of blood type O and A (in ABO system). On the other hand, both the levels of Le(b) antigens on RBC were higher in the groups of blood type O than in those of blood type A. We found both Le(a) and Le(b) antigens on RBC from a few blood type O subjects. We conclude that enhanced labeling and flow cytometry constitute a useful technique for the determination of Lewis antigens on RBC and that this method enables the precise quantification of such antigens.

Bacterial Proteins↗

PubMed1984

A method for quantitative analysis of the extent of necrosis in ischemic rat liver.

A method has been developed for quantitative analysis of necrotic regions in lobes of the rat liver 24 hr after temporary ischemia. Essentially the method consists of cutting the liver lobes into 2-mm-thick slices by means of a specially developed cutting apparatus. The serial slices are incubated in a special holder with tetranitro BT, which enables a clear discrimination between necrotic (unstained) and undamaged (stained) tissue. All slices from the ischemic lobes are photographed in the holder and submitted to morphometric analysis on enlarged prints. This method to obtain an estimate of the volume density of necrotic regions is rapid, simple, and reliable and compares favorably with other methods used in the literature. The extent of necrosis after 15-min clamping of the afferent vessels is virtually nil; it rises with longer periods of necrosis to reach a value of +/- 80% after 120 min.

Animals↗

PubMed1977

Quantitative analysis of macrophage phagocytosis by uptake of particulate 192iridium.

This study describes a method for the quantitation of macrophage phagocytosis by measuring the uptake of small particles of the radioactive inert metal, iridium (192Ir). It is shown that macrophage labeling with 192Ir was uniform, and the label was retained by the macrophages up to 21 days post-plating (when all cultures were terminated). 192Ir labeled macrophages were able to phagocytose other particles such as sheep red blood cells and were able to be activated to become tumorcidal in vitro 21 days following initial 192Ir uptake. Therefore, 192Ir could be a useful tool for the quantitative analysis and correlation of phagocytosis, tumor cytotoxicity and other macrophage functions.

Animals↗