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PubMed2003

Quantitative analysis of cortical pyramidal neurons after corpus callosotomy.

This study quantitatively explored the dendritic/spine extent of supragranular pyramidal neurons across several cortical areas in two adult male subjects who had undergone a callosotomy several decades before death. In all cortical areas, there were numerous atypical, supragranular pyramidal neurons with elongated "tap root" basilar dendrites. These atypical cells could be associated with an underlying epileptic condition and/or could represent a compensatory mechanism in response to deafferentation after callosotomy.

Adolescent↗
PubMed1975

Quantitative analysis of tribromsalan in blood and urine.

Tribromsalan can be quantitatively measured in whole blood and urine by a technique involving extraction with ethyl acetate, treatment with silica gel, separation by TLC, and quantitative measurement by fluorescent spectrophotometry. This method has a sensitivity down to 125 ng (25 ppb in 5.0 ml of sample) of free tribromsalan and shows an average 90% recovery of tribromsalan in blood and urine with standard deviations of 9.7 and 7.4%, respectively.

Animals↗
PubMed1981

[Serum proteins of growing Gunn rats. Quantitative analysis with agarose gel electrophoresis (author's transl)].

Microprocesses of quantitative agarose gel electrophoresis and biuret total protein evaluation were used for the quantitative estimation of the serum proteins of homozygous and heterozygous Gunn rats. For the analyses carried out in the course of hyperbilirubinemia, 6 microliter of serum were necessary in each case, of which 50-80 microgram were used for electrophoresis. The quantitative evaluation of the phoretogram curves plotted at two wavelengths was carried out with the aid of an analog computer. Eleven fractions were quantitatively covered by the process. Age-related concentration shifts were observed for a number of fractions, especially for albumin, transferrin, and IgG. The results obtained from a large number of animals in longitudinal and cross-sectional examination corroborate various reports found in the relevant literature.

Animals↗
PubMed2006

Quantitative analysis on volcanic ash surfaces: application of extended depth-of-field (focus) algorithm for light and scanning electron microscopy and 3D reconstruction.

The depth-of-field mainly affects the image quality either in scanning electron microscopy (SEM) or conventional light microscopy. The limited depth-of-field handicap of microscopy imaging can be used for obtaining "optically sectioned" specimens by moving the object along the optical axis. In this study, multiple images corresponding to different object planes were taken in order to overcome limited depth-of-field on conventional light microscope and SEM, estimation of an elevation surface and 3D reconstruction of different type volcanic ash surfaces. We used extended depth-of-field, a fusion algorithm that combines those images into one single sharp composite. Because of larger depth-of-field, we got higher-quality results even with image stacks taken by SEM with a fixed aperture in variable pressure mode. We calculated roughness descriptors, quadtree decomposition and greylevel standard deviation (sGL) and analyzed the shape of polar plots based on gradient analysis of constructed depth-maps. Furthermore, we calculated fractal dimensions of surfaces. Correlation analysis was performed to measure how these quantitative variables are related with different type ash surfaces. Roughness descriptors, quadtree decomposition, sGL and fractal dimension discriminate different types of volcanic ash surfaces.

Journal Article↗
PubMed1988

Quantitative analysis of linkage in macromolecules when one ligand is present in limited total quantity.

We present a general framework for analysis of two closely related problems in biochemical studies: (1) The first is analysis of binding data obtained under conditions in which a second, linked ligand is present in limited total quantity. In such conditions the free activity of the second ligand varies throughout the primary ligand binding curve, and the resultant behavior can be quite complex. Analysis of such curves enables one to quantitatively extract detailed information regarding the linkage of the two ligands at intermediate stages of ligation. The treatment is applied in an accompanying paper to oxygen binding in human hemoglobin in the presence of organic phosphates [Robert, C.H., Fall, L., & Gill, S. J. (1988) Biochemistry (following paper in this issue)]. (2) The second treatment we outline regards the analogous problem of analyzing differential scanning calorimetry (DSC) data obtained for a macromolecule binding a ligand present in limited quantity. A simple model is presented that accounts for dual transitions like those already seen in DSC data for human serum albumin in the presence of nonsaturating amounts of fatty acids [Ross, P., & Shrake, A. (1987) Abstracts of the 42nd Calorimetry Conference, University of Colorado, Boulder, CO].

Binding Sites↗
PubMed2000

Quantitative analysis of UVB-induced apoptosis in human epidermis.

The quantitative measurement of the induction of apoptosis in cells grown in vitro can be accomplished using a variety of proven methods. However, the quantitative assay of apoptosis within an intact tissue is very laborious and the results can be misleading. We have established a method to quantitatively analyze the induction of apoptosis in human epidermis following UVB irradiation. The assay is based on the activation of the apoptotically induced enzyme caspase 3, using a synthetic caspase 3 substrate. The activation of caspase 3 was shown to correlate with the induction of apoptosis in human keratinocytes cultures as a monolayer. We then demonstrated that the activation of caspase 3 could be measured from UVB-irradiated whole skin. The induction of apoptosis was confirmed by cellular morphology and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling. Therefore, we concluded that the measurement of caspase 3 specific activity in UVB-irradiated human epidermis was an efficient, inexpensive, and accurate method to quantitate UVB-induced apoptosis in vivo.

Apoptosis↗
PubMed1997

A quantitative analysis of sodium transport and removal during peritoneal dialysis.

To quantitatively evaluate peritoneal sodium transport, the diffusive mass transport coefficient (KBD) and sieving coefficient (S), as well as the mass of sodium transported by diffusion (DM), by convection (CM) and by fluid absorption (AM) and the total sodium mass removed (RM) were calculated during a series of single dwell studies in CAPD patients. A six-hour dwell study was performed in 68 patients using 2 liter of 1.36% (N = 13), 2.27% (N = 9) or 3.86% (N = 46) glucose dialysis fluid with 131I-albumin as the intraperitoneal volume marker. The patients in whom the 3.86% glucose dialysis fluid was applied were further divided into four transport groups according to a modified peritoneal equilibration test: high (H), high-average (H-A), low-average (L-A), and low (L) transport. There was no significant difference in KBD nor in S for sodium among different solutions. However, the removed sodium mass (RM) was significantly higher in the 3.86% (70.5 +/- 31.5 mmol) and 2.27% (36.0 +/- 21.0 mmol) solutions as compared to that of the 1.36% (-1.8 +/- 26 mmol) solution mainly due to increased both CM and DM. In general, CM was twice as high as DM. AM substantially decreased sodium removal. Among the different transport groups, the KBD and S values for sodium were significantly higher in the H group as compared to the other transport groups (both P < 0.05). However, RM was significantly lower in the H group mainly due to higher AM. Using a 3.86% glucose solution, the D/P for sodium was found to be significantly different (but only after 120 min of the dwell) between all the different transport groups. In conclusion, sodium removal in CAPD is strongly related to the fluid removal. The ultrafiltration induced convective transport (CM) and peritoneal absorption of sodium (AM) were of similar magnitude and were twice as high as the diffusive transport (DM) and both play an important role in the peritoneal sodium balance. A D/P for sodium using the 3.86% glucose solution, especially at the end of the dwell, can be used to discriminate between different transport categories of patients. High transport patients have a poor fluid and sodium removal that are likely to affect their clinical outcome.

Biological Transport↗
PubMed1994

Genetic variation detected by quantitative analysis of end-labeled genomic DNA fragments.

The continuing efforts to evaluate specific human populations for altered germinal mutation rates would profit from more efficient and more specific approaches than those of the past. To this end, we have explored the potential usefulness of two-dimensional electrophoresis of DNA fragments obtained from restriction-enzyme-digested genomic DNA. This permits the analysis, on a single preparation, of approximately 2000 DNA fragments varying in size from 1.0 to 5.0 kb in the first dimension and from 0.3 to 2.0 kb in the second dimension. To enter into a genetic analysis, these fragments must exhibit positional and quantitative stability. With respect to the latter, if spots that are the product of two homologous DNA fragments are to be distinguished with the requisite accuracy from spots that are the product of only one fragment, the coefficient of variation of spot intensity should be approximately < or = 0.12. At present, 482 of the spots in our preparations meet these standards. In an examination of preparations based on three Japanese mother/father/child trios, 43 of these 482 spots were found to exhibit variation that segregated within families according to Mendelian principles. We have established the feasibility of cloning a variant fragment from such gels and establishing its nucleotide sequence. This technology should be highly efficient in monitoring for mutations resulting in loss/gain/rearrangement events in DNA fragments distributed throughout the genome.

Base Sequence↗
PubMed1985

Development of quantitative analysis of plasma thromboxane B2 by gas chromatography-mass spectrometry.

In order to diagnose patients in thrombotic state, it is quite important to detect increased concentration of plasma thromboxane B2 (TXB2), a stable catabolite of TXA2. To determine plasma TXB2 levels with high sensitivity and selectivity, we employed gas chromatography-mass spectrometry (GC/MS). The trimethylsilyl (TMS) ether derivatives conventionally employed in GC/MS analysis of prostanoids are not suitable for quantitation of plasma prostanoids, because the mass spectra are deficient in ions with high intensity in the high mass range and TMS ether derivatives are sensitive to moisture. To solve these problems we employed tert-butyldimethylsilyl (t-BDMS) ether derivatives, based on the observation that t-BDMS ether derivatives afforded abundant ions at [M-57]+ and showed good hydrolytic stability. The reaction conditions of tert-butyldimethylsilylation were also examined to optimize the selected ion monitoring response. The t-BDMS ether derivatives of prostanoids were successfully analyzed with a short capillary column with a relatively large diameter, with maintaining good separation. In conjunction with the use of reversed-phase high performance liquid chromatography as purification procedure, a sensitive and reproducible stable isotope dilution assay of plasma TXB2 was developed. The values obtained by this method correlated well with those obtained by the radioimmunoassay we have developed.

6-Ketoprostaglandin F1 alpha↗
PubMed2006

Quantitative analysis reveals asynchronous and more than DSB-associated histone H2AX phosphorylation after exposure to ionizing radiation.

Rapid phosphorylation of histone H2AX after exposure of cells to ionizing radiation occurs at DSB sites and extends to a region including as much as 30 Mbp of chromatin to form visible microscopic structures called gamma-H2AX foci. Although the kinetics of total cellular histone H2AX phosphorylation after irradiation has been characterized, we still know little about the phosphorylation kinetics of individual gamma-H2AX foci. In addition, there are hundreds of smaller gamma-H2AX foci that are not associated with DNA double-strand breaks. We refer to these sites as DSB-unrelated gamma-H2AX foci. By using indirect immunofluorescence microscopy, deconvolution and three-dimensional image analysis, we established an objective method to quantitatively analyze each gamma-H2AX focus as well as to discriminate DSB-related gamma-H2AX foci from DSB-unrelated gamma-H2AX foci. Using this method, we found that histone H2AX phosphorylation at different DSB sites was asynchronous after exposure to ionizing radiation. This may reflect the heterogeneous characteristic of free DNA ends that are generated under these conditions. In addition, we found that increased histone H2AX phosphorylation also occurred outside of DSB sites after exposure to ionizing radiation. The function of this DSB-unassociated phosphorylation is not known.

Cell Line, Tumor↗
PubMed1998

RNA quantitative analysis from fixed and paraffin-embedded tissues: membrane hybridization and capillary electrophoresis.

Fixed and paraffin-embedded tissues from pathology department archives are available for RNA expression analysis. We describe a general method for quantitation of specific RNA sequence extracted from single 6-8-micron human histological tissue sections cut from paraffin blocks. For each specific mRNA, the range of linear relationship between the log of the initial total RNA concentration and the log of the specific product after reverse transcription (RT)-PCR must be established. We usually perform RT with avian myeloblastosis virus (AMV)-RT, using specific antisense primers and a variable number of cycles of PCR amplification. The number of cycles must be adjusted within the range in which a linear relationship exists between the log of the amount of amplification product and the number of cycles. The quantity of specific product is standardized relative to beta-actin mRNA to normalize for the degree of RNA degradation, which can be quite different among samples. The amplification products were quantified by dot blot and 32P-labeled hybridization probe or by capillary electrophoresis with a laser-induced fluorescence detector. The intratest variation range was for the dot blot mean +/- 10% standard deviation (SD) and for the capillary electrophoresis mean +/- 3% SD.

Actins↗
PubMedDate not supplied

[Quantitative analysis of polypeptides by disc electrophoresis in pore gradients].

The quantitation of components in a complex mixture of proteins of Pseudomonas denitrificans separated by disc-electrophoresis in the linear pore gradient of polyacrylamide gel was studied. The problem of a poor staining of proteins in the presence of a detergent was solved by a high resolving power photography. A linear correlation between the amount of protein in the fraction and the intensity of amide black staining was extablished. In comparison to the wild type of P. denitrificans the aldehyde negative mutant showed significant changes in protein fractions amounting to 30% of total protein, according to the densitometrical data. It is suggested that the changes are related to the protein migration in fractions rather than to an additional synthesis in different protein fractions.

Bacterial Proteins↗
PubMed1977

Quantitative analysis of biological marker synthesis in tumor cell cycle.

A quantitative relationship between tumor cell number and biologic marker concentration has been investigated and characterized by the previously developed discrete-time kinetic model for the study of cell kinetics. Here, this model is further expanded to cope with both cell cycle kinetics and biologic marker synthesis. A synchronized tumor-cell population is examined to determine the time course of the synthesis of markers in relation to cell cycle. The DNA content distributions, measured by flow microfluorometry, are analyzed by use of the model, and the cell age distribution is extracted. The average marker content per cell in cell cycle is measured for each time sequence in synchronized cell populations. The model, incorporating the cell age distribution and the average marker content per cell in cell cycle, enables one to generate the marker content distribution, from which the cell number is estimated from the marker concentration. The model performance is further evaluated with Chinese hamster ovary cells, and their polyamine content and the total polyamine concentration during synchronization is calculated and related to the total cell number.

Cell Division↗
PubMed1997

Quantitative analysis of cardiovascular MR images.

The diagnosis of cardiovascular disease requires the precise assessment of both morphology and function. Nearly all aspects of cardiovascular function and flow can be quantified nowadays with fast magnetic resonance (MR) imaging techniques. Conventional and breath-hold cine MR imaging allow the precise and highly reproducible assessment of global and regional left ventricular function. During the same examination, velocity encoded cine (VEC) MR imaging provides measurements of blood flow in the heart and great vessels. Quantitative image analysis often still relies on manual tracing of contours in the images. Reliable automated or semi-automated image analysis software would be very helpful to overcome the limitations associated with the manual and tedious processing of the images. Recent progress in MR imaging of the coronary arteries and myocardial perfusion imaging with contrast media, along with the further development of faster imaging sequences, suggest that MR imaging could evolve into a single technique ('one stop shop') for the evaluation of many aspects of heart disease. As a result, it is very likely that the need for automated image segmentation and analysis software algorithms will further increase. In this paper the developments directed towards the automated image analysis and semi-automated contour detection for cardiovascular MR imaging are presented.

Blood Flow Velocity↗
PubMed1993

Quantitative analysis of stress fiber orientation during corneal wound contraction.

Previous studies of actin and actin-binding proteins in corneal myofibroblasts suggest the development of a contractile apparatus composed, in part, of F-actin micro-filament bundles, i.e. stress fibers. To better understand the mechanics of wound contraction and the relationship between microfilament bundles and wound closure, we have analyzed the spatial and temporal organization of stress fibers during the process of corneal wound healing. Rabbit corneas (26 eyes) received 6 mm full-thickness, central incisions and were studied at various times for F-actin organization using en bloc (whole cornea) staining with FITC-phalloidin, as well as conventional histological techniques. 3-D datasets (z-series of 40 en face optical sections, 1 micron steps) were collected using the Biorad MRC-600 laser scanning confocal microscope at various regions within the wound. At 7 days, 3-D analysis showed randomly oriented, interconnected F-actin filament bundles (stress fibers). Between 7 and 28 days, stress fibers appeared to organize gradually into planes parallel to the wound surface, with a large population achieving a final orientation nearly parallel to the long axis of the wound. Using Fourier Transform analysis techniques, an orientation index (OI) was calculated to quantitate global fiber orientation at each time point. Analysis of variance demonstrated a significant change (P < 0.001) in overall stress fiber orientation from a random distribution at day 7 to an alignment more parallel to the lateral wound borders at day 28. Overall, these data suggest that stress fibers undergo temporal changes in spatial organization that correlate with wound closure, and that wound closure does not involve the development of previously described contractile or tractional forces aligned directly across the wound.

Actin Cytoskeleton↗
PubMed1995

Coronary arteriography for quantitative analysis: experimental and clinical comparison of cinefilm and video recordings.

Although use of videotape for the recording of coronary angiograms continues to grow, the validity of quantitative coronary angiographic analysis of video images remains unknown. To estimate the reliability of angiographic images recorded on videotape, experimental and clinical angiograms were recorded simultaneously on both 35 mm cinefilm and super-VHS videotape with normal images and with spatial filtering of the images (edge enhancement) on a digital cardiac imaging system. The experimental angiographic studies were performed with plexiglass blocks and stenosis phantom of 0.5 to 3.0 mm in diameter. The clinical angiograms were recorded in 20 patients undergoing percutaneous transluminal coronary angioplasty (31 frames before and 20 frames after percutaneous transluminal coronary angioplasty). The cinefilm and corresponding videotapes were analyzed off-line with the new version of the coronary angiography analysis system. For the experimental study, measurements of minimal luminal diameter obtained from cinefilm, normal-image videotape, and edge-enhanced videotape were compared with the true phantom diameter. In the clinical study the agreement between measurements obtained from cinefilm and measurements from normal-image videotape and edge-enhanced videotape was examined. In the phantom series the accuracy and precision of quantitative coronary angiography measurement for cinefilm were -0.10 +/- 0.08 mm, for normal-image videotape -0.11 +/- 0.18 mm, and for edge-enhanced videotape -0.10 +/- 0.11 mm (mean +/- SD). In the clinical series, the differences between measurements from cinefilm and normal-image videotape were 0.14 +/- 0.20 mm and from cinefilm and edge-enhanced videotape 0.04 +/- 0.13 mm.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗
PubMed1994

Quantitative analysis of the neu oncogene in normal and transformed epithelial breast cells by fluorescence in situ hybridization and laser scanning microscopy.

In this study we evaluated indirect fluorescence in situ hybridization of the neu oncogene in combination with laser scanning microscopy for the detection and quantification of fluorescence signals in single cells. Cell lines from human tumor tissue with neu oncogene amplification and one nonneoplastic human epithelial cell line from a lactating breast with a neu single copy as the reference were used. After quantitative fluorescence analysis of three mixed cell populations (neoplastic cells and reference cells), we evaluated the cell morphology and location of the fluorescence signal by laser scanning microscopy. Finally, the number of oncogene copies in the tumor cell population could be estimated from the ratio of its mean background-corrected integrated fluorescence intensities to those of the reference cells. In all mixed cultures the ratio of fluorescence intensities was within the limits of oncogene copy numbers known from the literature and evaluated by southern blot analysis. The lowest oncogene copy number possible to quantify was four to eight genomic copies.

Breast Neoplasms↗
PubMed1983

Spermatogenesis in the vasectomized monkey: quantitative analysis.

The seminiferous epithelium in mature vasectomized Macaca fascicularis was examined quantitatively to assess spermatogenesis. Monkeys were bilaterally vasectomized and controls were bilaterally sham operated. At postoperative periods of 10 and 18 months, groups of monkeys were castrated and their testes prepared for morphologic analysis. Diameters were measured in 100 cross sections of seminiferous tubules from each animal. Numbers of spermatogonia (Ad and Ap), preleptotene spermatocytes, pachytene spermatocytes, and step 7 spermatids, relative 10 Sertoli cell nucleoli, were counted in stage VII tubules. Tubule diameter and germ cell numbers per Sertoli cell nucleoli were not altered by vasectomy. Our study demonstrates quantitatively that spermatogenesis in the monkey is not inhibited up to 18 months following vasectomy.

Animals↗