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PubMed2001

Quantitative analysis of videostroboscopic images in presbylarynges.

OBJECTIVE/HYPOTHESIS: Age-related dysphonia, or presbylarynges, is often identified as the cause of voice disorders in older individuals. It is a diagnosis of exclusion that typically includes the subjective videostroboscopic findings of vocal fold bowing or atrophy and incomplete glottal closure. We hypothesize that vocal fold bowing correlates directly with glottal gap in patients with presbylarynges and that these characteristics may be quantified objectively using measures obtained from videostroboscopic images. STUDY DESIGN: Retrospective analysis of patient data and prospective analysis of control subjects. METHODS: The quantitative measures of bowing index and normalized glottal gap, as well as a novel measure, normalized laryngeal outlet, were calculated from the videostroboscopic examinations of 46 patients with presbylarynges and 20 normal control subjects. RESULTS: The mean bowing index values from the presbylarynges and control groups differed significantly, although there was overlap of individual values between groups. Bowing index values did not consistently predict normalized glottal gap values. Mean normalized laryngeal outlet values of the patients with presbylarynges were significantly smaller than those of the control group. CONCLUSIONS: Bowing does not consistently predict the extent of glottal gap. Therefore, other presbylaryngeal changes are probably contributing to incomplete glottal closure, which are not well-visualized stroboscopically, so the finding of bowing is not sufficiently specific to identify presbylarynges. The significantly smaller normalized laryngeal outlet values suggest that this identifies a compensatory strategy for glottal gap to optimize vocal function. This is a novel finding that contrasts with medial ventricular fold squeezing, which is more routinely sought and is typically considered a maladaptive compensatory strategy. Despite the advantages of quantitative stroboscopic measures, limitations in reliability limit their clinical utility.

Aging↗
PubMed1999

Discrimination between benign and malignant melanocytic skin lesions by multivariate analysis, quantitative S-100 immunohistochemistry, nuclear morphometry and DNA cytometry.

OBJECTIVE: To determine whether combined quantitative immunohistochemistry of S-100, nuclear morphometry and DNA image cytometry improves discrimination between benign and malignant melanocytic skin lesions (MSLs). STUDY DESIGN: S-100 protein expression was measured in tissue sections of MSLs using an image cytometry system. Localized areas of high S-100 expression were used to identify regions in sequential, facing sections in which morphometric and cytometric features of nuclei, including DNA ploidy, were also measured. RESULTS: Malignant cases had significantly higher S-100 protein staining intensity, larger nuclei and greater DNA content (P < .05). High staining intensity for S-100 protein weakly correlated with variation in size of the mean nuclear area (P = .04) and DNA content (P = .03). Combining the features of nuclear area and DNA integrated optical density in areas of high-intensity staining for S-100 protein discriminated more accurately between 12 benign and 16 malignant areas than any of the features along (P = .0003). CONCLUSION: Combined multivariate quantitative immunohistochemical, morphometric and DNA cytometric analysis greatly improves discrimination between benign MSLs and malignant melanoma. Larger test sets are required to confirm the promising results of this initial study.

Cell Nucleus↗
PubMed1982

Computerized rapid high resolution quantitative analysis of plasma lipoproteins based upon single vertical spin centrifugation.

A method has been developed for rapidly quantitating the cholesterol concentration of normal and certain variant lipoproteins in a large number of patients (over 240 in one week). The method employs a microcomputer interfaced to the vertical autoprofiler (VAP) described earlier (Chung et al. 1981. J. Lipid Res. 22: 1003-1014). Software developed to accomplish rapid on-line analysis of the VAP signal uses peak shapes and positions derived from prior VAP analysis of isolated authentic lipoproteins HDL, LDL, and VLDL to quantitate these species in a VAP profile. Variant lipoproteins VHDL (a species with density greater than that of HDL(3)), MDL (a species, most likely Lp(a), with density intermediate between that of HDL and LDL), and IDL are subsequently quantitated by a method combining difference calculations with curve shapes. The procedure has been validated qualitatively by negative stain electron microscopy, gradient gel electrophoresis, strip electrophoresis, chemical analysis of the lipids, radioimmunoassay of the apolipoproteins, and measurement of the density of the peak centers. It has been validated quantitatively by comparison with Lipid Research Clinic methodology for HDL-, LDL-, and VLDL-cholesterol, and for MDL- and IDL-cholesterol by comparison of the amounts of MDL or IDL predicted to be present by the method with that known to be present following standard addition to whole plasma. These validations show that the method is a rapid and accurate technique of lipoprotein analysis suitable for the routine screening of patients for abnormal amounts of normal or variant lipoproteins, as well as for use as a research tool for quantitation of changes in cholesterol content of six or seven different plasma lipoprotein fractions.-Cone, J. T., J. P. Segrest, B. H. Chung, J. B. Ragland, S. M. Sabesin, and A. Glasscock. Computerized rapid high resolution quantitative analysis of plasma lipoproteins based upon single vertical spin centrifugation.

Apolipoproteins↗
PubMed1987

Quantitative analysis of a nuclear antigen in interphase and mitotic cells.

The quantification of an interchromatin-associated antigen, designated p 105, during cellular passage through mitosis is described. Indirect immunofluorescence microscopy and immunogold electron microscopy demonstrated a qualitative increase in p 105 within the mitotic cytoplasm. Multiparameter flow cytometric analysis was performed on fixed cells sequentially stained with anti-p 105 immunofluorescence and/or propidium iodide. This analysis demonstrated approximately a tenfold increase in intracellular p 105 content as a function of progression from the G2 to the M phase. This increase was corroborated by the quantitative immunoblot analysis of colchicine-treated cell cultures and of cells sorted on the basis of anti-p 105 immunofluorescence. The data reveal that the increased levels of anti-p 105 immunofluorescence in conjunction with flow cytometry may be used effectively to quantitate mitotic index and isolate mitotic cells. The function and modulation of p 105 throughout the cell cycle is discussed.

Antigen-Antibody Complex↗
PubMed2005

Numerical approaches for quantitative analysis of two-dimensional maps: a review of commercial software and home-made systems.

The present review attempts to cover a number of methods that have appeared in the last few years for performing quantitative proteome analysis. However, due to the large number of methods described for both electrophoretic and chromatographic approaches, we have limited this review to conventional two-dimensional (2-D) map analysis which couples orthogonally a charge-based step (isoelectric focusing) to a size-based separation step (sodium dodecyl sulfate-electrophoresis). The first and oldest method applied to 2-D map data reduction is based on statistical analysis performed on sets of gels via powerful software packages, such as Melanie, PDQuest, Z3 and Z4000, Phoretix and Progenesis. This method calls for separately running a number of replicas for control and treated samples. The two sets of data are then merged and compared via a number of software packages which we describe. In addition to commercially-available systems, a number of home made approaches for 2-D map comparison have been recently described and are also reviewed. They are based on fuzzyfication of the digitized 2-D gel image coupled to linear discriminant analysis, three-way principal component analysis or a combination of principal component analysis and soft-independent modeling of class analogy. These statistical tools appear to perform well in differential proteomic studies.

Cluster Analysis↗
PubMed1984

Quantitative analysis of seven-pinhole tomographic thallium-201 scintigrams: improved sensitivity and estimation of the extent of coronary involvement by evaluation of radiotracer uptake and clearance.

Recent studies have shown that the sensitivity of conventional thallium-201 scintigraphy can be increased by the quantitative assessment of myocardial radiotracer clearance rates in conjunction with the evaluation of radionuclide uptake. In this study, a similar analysis of tomographic scintigrams was performed to determine the feasibility and value of this approach, particularly in estimating the extent of disease and detecting three vessel coronary involvement. Seventy patients undergoing cardiac catheterization for chest pain were studied by exercise and 3 hour delayed thallium-201 scintigrams using the seven-pinhole tomographic technique. Each study was evaluated by visual inspection of the tomographic sections and quantitative analysis. The latter approach consisted of comparing circumferential profiles of the initial post-exercise radionuclide uptake and the 3 hour clearance rates generated from each of three left ventricular slices with similar profiles representing the lower 95% confidence limits derived from 15 middle-aged volunteers. An abnormality was considered present when a patient's profile fell below these limits for a 30 degrees arc, and was ascribed to disease in a particular artery when it involved that vessel's usual distribution. Among the 61 patients without apparent primary myocardial or valvular disease, the diagnostic sensitivity of thallium scintigraphy was increased from 86% (43 of 50) to 96% (48 of 50) without a change in specificity (both 9 of 11 or 82%). More importantly, the quantitative approach permitted detection of 85% (107 of 126) of significantly obstructed coronary vessels compared with 47% (59 of 126) by visual analysis (p less than 0.001), again without sacrificing specificity (85 versus 87%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2002

Quantitative analysis of tryptophan analogue incorporation in recombinant proteins.

Three different methods to quantitate tryptophan (Trp) analogue incorporation into recombinant proteins are described: first, spectroscopic analysis based on a linear combination of the absorption spectra of the aromatic residues in the denatured Trp-containing or analogue-substituted protein; second, chromatographic separation of analogue-substituted and Trp-containing proteins by HPLC; and third, mass spectrum analysis of the mixture of analogue-substituted and Trp-containing proteins. An accurate estimate of analogue incorporation in single-Trp proteins can be obtained directly by either analysis of the absorption spectrum or HPLC chromatography. While analysis of the absorption spectrum or HPLC chromatogram can provide an assessment of the average level of analogue incorporation for proteins that contain two or more Trp residues, mass spectroscopy analysis of peptides generated by protease digestion and separated by HPLC provides a general method for a complete quantitative description of the distribution of analogue incorporation. The more complex analysis by mass spectroscopy becomes important for multi-Trp proteins because the distribution of analogue versus Trp-containing polypeptide chains may not be the same as that predicted on the basis of average level of analogue incorporation.

Chromatography, High Pressure Liquid↗
PubMed1976

Age-related changes in hepatic fine structure: a quantitative analysis.

Age-related changes in hepatic fine structure were quantitatively evaluated in virgin and retired breeder (RB) male rats by morphometric analysis. Centrolobular hepatocytes increase in size, at least up to 480 days of age, and this increase is reflected in larger volumes of nuclei, cytoplasm, organelles, and ground substance. The surface area of the smooth-surfaced endoplasmic reticulum (SER) continues to increase with age in both groups of animals, although there is a significantly greater amount of both SER and rough-surfaced endoplasmic reticulum in the livers of the virgin rats. In addition, aging is accompanied by a gradual increase in the relative volume of the lysosomes and a linear decrease in the surface area of the Golgi membranes. Evidence from this study suggests that specific alterations in hepatic fine structure occur as a function of age.

Aging↗
PubMed1984

A quantitative analysis of the cytotoxic action of chemical mutagens.

A quantitative hypothesis is developed to explain the cytotoxic action of chemical mutagens on eukaryotic cells. The hypothesis forms an extrapolation of previously developed concepts used to explain the effect of ionizing radiation and the cytotoxic action of UV light. The crucial potentially lethal lesion is assumed to be a DNA double-strand lesion which may be an interstrand cross-link or a pair of DNA single-strand alkylations, for example. The effect of repair processes is included in the analytical equation derived to describe cell survival. The analysis of several sets of cell survival data for different chemical mutagens is used to demonstrate the applicability of the hypothesis. The logical extension of the hypothesis permits a division of chemical mutagens into 4 separate classes on the basis of the mechanisms proposed for the cytotoxic activity, and the relative importance of the risk associated with low-level exposure to each class is discussed. The hypothesis is amenable to further experimental verification.

Animals↗
PubMed2001

Field nonuniformity correction for quantitative analysis of digitized mammograms.

Several factors, including the heel effect, variation in distance from the x-ray source to points in the image and path obliquity contribute to the signal nonuniformity of mammograms. To best use digitized mammograms for quantitative image analysis, these field non-uniformities must be corrected. An empirically based correction method, which uses a bowl-shaped calibration phantom, has been developed. Due to the annular spherical shape of the phantom, its attenuation is constant over the entire image. Remaining nonuniformities are due only to the heel and inverse square effects as well as the variable path through the beam filter, compression plate and image receptor. In logarithmic space, a normalized image of the phantom can be added to mammograms to correct for these effects. Then, an analytical correction for path obliquity in the breast can be applied to the images. It was found that the correction causes the errors associated with field nonuniformity to be reduced from 14% to 2% for a 4 cm block of material corresponding to a combination of 50% fibroglandular and 50% fatty breast tissue. A repeatability study has been conducted to show that in regions as far as 20 cm away from the chest wall, variations due to imaging conditions and phantom alignment contribute to <2% of overall corrected signal.

Breast↗
PubMed2003

Preliminary evaluation of a fuzzy logic-based automatic quantitative analysis in myocardial SPECT.

UNLABELLED: This study validates a new quantitative myocardial perfusion SPECT software. METHODS: The processing starts with the extraction of the morphologic skeleton of the left ventricular myocardium from reconstructed transverse sections. Fuzzy logic is used to decide whether a pixel belongs to the myocardium and any perfusion defect is filled according to a truncated bullet model. The resulting image is partitioned in 18 isovolumetric sectors. Sex-matched normal limits, criteria of abnormality for rest (201)Tl and (99m)Tc-labeled perfusion tracers, reproducibility studies, and detection of coronary artery disease were developed and validated in an overall population of 343 patients. The sex- and tracer-matched means and SDs of a normal response were calculated in 93 male and 93 female patients with a <5% likelihood of coronary artery disease. Reproducibility measurements and assignment of different sectors of the myocardium to a specific coronary were performed from data collected in 49 and 60 patients, respectively. The accuracy of the detection of a coronary artery occlusion was assessed in 48 patients who also underwent coronary angiography. RESULTS: The intra- and interoperator reproducibility of the sectorial activity was high with a linear regression coefficient of 0.97 and a SD of the difference measurement at 4.4% and 3.8%, respectively. Overall sensitivity and specificity for the detection of occluded coronary artery were 90% and 80%, respectively. For the detection of left anterior descending, left circumflex, and right artery coronary occlusion, sensitivity was 92%, 75%, and 92.5%, respectively, and specificity was 75%, 78%, and 90%, respectively. CONCLUSION: The new quantitative myocardial perfusion SPECT software appears to be a very helpful program for the objective analysis of perfusion tracer distribution in myocardial SPECT and a very accurate tool in the detection and localization of coronary artery occlusion.

Algorithms↗
PubMed2006

Quantitative analysis of messenger RNA abundance for ribosomal protein L-15, cyclophilin-A, phosphoglycerokinase, beta-glucuronidase, glyceraldehyde 3-phosphate dehydrogenase, beta-actin, and histone H2A during bovine oocyte maturation and early embryogenesis in vitro.

Real-time reverse transcription PCR has greatly improved the ease and sensitivity of quantitative gene expression studies. However, measurement of gene expression generally requires selection of a valid reference (housekeeping gene) for data normalization to compensate for inherent variations. Given the dynamic nature of early embryonic development, application of this technology to studies of oocyte and early embryonic development is further complicated due to limited amounts of starting material and a paucity of information on constitutively expressed genes for data normalization. We have validated quantitative procedures for real-time reverse transcription polymerase chain reaction (RT-PCR) analysis of mRNA abundance during bovine meiotic maturation and early embryogenesis and utilized this technology to determine temporal changes in mRNA abundance for ribosomal protein L-15, cyclophilin-A, phosphoglycerokinase, beta-glucuronidase, glyceraldehyde-3-phosphate dehydrogenase, beta-actin, and histone H2A. Quantification of amounts of specific exogenous RNAs added to samples revealed acceptable rates of RNA recovery and efficiency of reverse transcription with minimal variation. Progression of bovine oocytes to metaphase II resulted in reduced abundance of polyadenylated, but not total transcripts for majority of above genes; however phosphoglycerokinase exhibited a significant decline in both RNA populations. Abundance of mRNAs for above genes in early embryos generally remained low until the blastocyst stage, but abundance of ribosomal protein L-15 mRNA was increased at the morula stage and histone H2A mRNA showed dynamic changes prior to embryonic genome activation. Results demonstrate a valid approach for quantitative analysis of mRNA abundance in oocytes and embryos, but do not support constitutive expression of above genes during early embryonic development.

Actins↗
PubMed1995

Quantitative analysis of cytomegalovirus viremia in lung transplant recipients.

A quantitative culture method was used to test serial blood specimens from 28 lung transplant recipients at risk of cytomegalovirus (CMV) infection (donor [D] or recipient [R] seropositive for CMV). Viremia occurred in 26 (93%) of 28 patients. Highest levels were seen when the donor was seropositive. The median of individual maximum levels was 2.13 infectious centers (ICs/10(5) leukocytes for D+/R- patients (interquartile range [iqr], 0.12-21.77), 1.01 for D+/R+ (iqr, 0.3-2.32), and 0.10 for D-/R+ (iqr, 0.07-0.36; P = .030, Kruskal-Wallis test). Higher levels were seen in patients with biopsy-proven CMV pneumonitis compared with those with negative biopsies (mean, 0.24 [SD 0.51] ICs/10(5) leukocytes vs. 0.01 [SD 0.03]; P = .039, Wilcoxon test) and with symptomatic CMV episodes compared with asymptomatic episodes (median, 0.34 ICs/10(5) [iqr, 0.11-0.61] vs. 0.08 ICs/10(5) [iqr, 0.03-0.13]; P = .045, Wilcoxon test). Further studies are required to determine whether quantification of CMV viremia by this method will be of practical value in the recognition of significant CMV infection in lung transplant recipients.

Antigens, Viral↗
PubMed1997

Expression of the five somatostatin receptor (SSTR1-5) subtypes in rat pituitary somatotrophes: quantitative analysis by double-layer immunofluorescence confocal microscopy.

Using quantitative double-label fluorescence immunocytochemistry and confocal microscopy, we have analysed the pattern of expression of SSTR1-5 in normal rat pituitary somatotrophes. Antipeptide rabbit polyclonal antibodies were produced against the extracellular domains of SSTR1-5. SSTR antigens were colocalized in GH positive cells using rhodamine conjugated secondary antibody for SSTRs and FITC-conjugated secondary antibody for GH. SSTR5 was the predominant subtype which was expressed in 86 +/- 9.7% of GH cells followed by SSTR2 in 42 +/- 6.4% of GH positive cells. SSTR4 and SSTR3 were modestly expressed in 23 +/- 4.7% and 18 +/- 3.2% of somatotrophes respectively whereas SSTR1 was the least expressed subtype occurring in only 5 +/- 1.2% of somatotrophes. These results demonstrate variable expression of the 5 SSTRs in somatotrophes. The preponderance of the SST-28 preferring SSTR5 subtype correlates with the reported higher potency of SST-28 than SST-14 for inhibiting GH secretion.

Animals↗
PubMed1986

Stability of endotoxin detected in human plasma against endotoxin-inactivating factor (EIF): quantitative analysis of EIF using chromogenic endotoxin assay.

Using a quantitative blood endotoxin assay utilizing chromogenic substrate coupled with perchloric acid pretreatment (PCA-LCT), we showed the presence of endotoxin-inactivating factor (EIF) in human plasma in vitro. EIF activity inactivated added endotoxin to about 10(-4) of the initial level within 20 min, followed by a stable phase where the residual endotoxin became resistant to EIF and was not further inactivated. The residual endotoxin may represent the endotoxin in patient plasma which is also EIF resistant. We postulate that endotoxin, upon entering the blood, is rapidly inactivated by chemical modification of its active site, lipid A, through EIF. Subsequently, inactivated endotoxin, mainly consisting of polysaccharide, is gradually removed from circulation by endocytosis in the reticuloendothelial system.

Chromogenic Compounds↗
PubMed2006

[Development of ELISA-kit of quantitative analysis for Zearalenone].

OBJECTIVE: To develope a rapid, sensitive, quantitative ELISA-kit for Zearalenone and determine zearalenone in cereals. METHODS: On the base of monoclonal antibodies against ZEN, apply indirect ELISA to study the performance parameter of the kit. RESULTS: The limited concentration of detection of the ELISA-kit was 1ng/ml, linear range was 1-200 ng/ml, the linear equation was Y = 0.99 - 0.40 x (R2 = 0.99). The inhibition concentration of 50% against ZEN was 16.3 ng/ml. The average recovery rate of spiked corn and wheat was 96.5% and 95.5%, respectively, the coefficient of variant was 13.2% and 10.9%, respectively. The kit can be stored at 4 degrees C over 6 months. The cross reaction rate with the other mycotoxins was less than 1%, and coefficient of variant within-laboratory and between-laboratory was less than 15% and less than 20%, respectively. Detecting the VICAM sample with ELISA method and HPLC method, the results were within the range of the sample, and there was no statistic difference between the two methods. CONCLUSION: This ELISA-kit was quick, sensitive, stable and specific and can be used to determine ZEN in cereals.

Edible Grain↗
PubMed2006

Simultaneous quantitative analysis of bioactive sphingolipids by high-performance liquid chromatography-tandem mass spectrometry.

There has been a recent explosion in research concerning novel bioactive sphingolipids (SPLs) such as ceramide (Cer), sphingosine (Sph) and sphingosine 1-phosphate (Sph-1P) that necessitates development of accurate and user-friendly methodology for analyzing and quantitating the endogenous levels of these molecules. ESI/MS/MS methodology provides a universal tool used for detecting and monitoring changes in SPL levels and composition from biological materials. Simultaneous ESI/MS/MS analysis of sphingoid bases (SBs), sphingoid base 1-phosphates (SB-1Ps), Cers and sphingomyelins (SMs) is performed on a Thermo Finnigan TSQ 7000 triple quadrupole mass spectrometer operating in a multiple reaction monitoring (MRM) positive ionization mode. Biological materials (cells, tissues or physiological fluids) are fortified with internal standards (ISs), extracted into a one-phase neutral organic solvent system, and analyzed by a Surveyor/TSQ 7000 LC/MS system. Qualitative analysis of SPLs is performed by a Parent Ion scan of a common fragment ion characteristic for a particular class of SPLs. Quantitative analysis is based on calibration curves generated by spiking an artificial matrix with known amounts of target synthetic standards and an equal amount of IS. The calibration curves are constructed by plotting the peak area ratios of analyte to the respective IS against concentration using a linear regression model. This robust analytical procedure can determine the composition of endogenous sphingolipids (ESPLs) in varied biological materials and achieve a detection limit at 1 pmol or lower level. This and related methodology are already defining unexpected specialization and specificity in the metabolism and function of distinct subspecies of individual bioactive SPLs.

Animals↗