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PubMed2006

[Preparation and quantitative analysis of methyl phenyl carbonate standard sample].

The preparation and quantitative analytical method for high-purity methyl phenyl carbonate (MPC) was developed. Dimethyl carbonate (DMC) and diphenyl carbonate (DPC) were firstly used as reactants to synthesize MPC catalyzed by TiO2/SiO2 because the disproportionation of MPC is reversible and the reverse reaction is thermodynamically favorable. The high-purity MPC standard sample was obtained by reduced pressure distillation and the removal of minor phenol with dilute sodium hydroxide solution. The qualitative analysis by gas chromatography-mass spectrometry (GC-MS) showed there were minor phenol and diphenyl carbonate in the MPC sample. The mass percent concentration of water in the MPC sample was 0.26%, which was determined by Karl Fischer titration. A gas chromatographic method with an OV-101 capillary column was established for quantifying the minor phenol and DPC in the MPC sample. The quantitative results showed the mass concentrations of phenol and DPC were 2.04% and 1.59%, respectively. The difficulty to analyze MPC, the intermediate product of the transesterification of DMC and phenol, was solved with the self-made MPC standard sample.

English Abstract↗
PubMed1990

A quantitative analysis of placental vasculature in the third-trimester fetus with autosomal trisomy.

Growth disturbance in the trisomic fetus is believed to be primarily fetal in origin. There has been only sparse description of placental pathology in the third trimester in these fetuses, and therefore the placental role in their growth and development remains unexplored. We performed quantitative morphometric analysis on the placentas of 18 fetuses with trisomy and ten normal control fetuses. Doppler umbilical artery analysis was performed on ten abnormal fetuses and all controls. The placentas of trisomic fetuses exhibited a significant reduction in small muscular artery count and small muscular artery/villus ratio. Abnormal Doppler waveforms correlated closely with reduced small muscular artery counts. Undervascularization and increased vascular resistance of the placenta of trisomic fetuses may contribute to diminished fetal growth. The placenta appears to be another fetal organ whose structure and function are affected adversely by abnormal karyotype.

Arterioles↗
PubMed2004

Incremental diagnostic value of quantitative analysis of double phase Tc-99m MIBI scintimammography for the detection of primary breast cancer additive to visual analysis.

UNLABELLED: Tc-99m MIBI scintimammography (SMM) is known to be a useful diagnostic tool for primary breast cancer. We conducted this study to establish optimal visual grades for the detection of primary breast cancer and to investigate whether the quantitative indices of double phase SMM could provide incremental diagnostic value additive to visual analysis. METHODS: Five hundred and twenty highly suspected breast cancer patients (malignant: 370; benign: 150) were included in this study. Double phase Tc-99m MIBI SMM (early: 10 min; delayed: 3 h) was performed after injection of 750 MBq of Tc-99m MIBI. For visual analysis, five scoring method was used. The early and delayed lesion to non-lesion ratios (L/N) and retention index (RI) were calculated. Receiver operating characteristic curve (ROC) analyses was performed to determine the optimal visual grade, to calculate cut-off value of quantitative indices for differentiation malignant and benign diseases and to investigate whether the quantitative indices could provide incremental diagnostic value additive to visual analysis. To investigate the incremental diagnostic value of quantitative index in variable tumor size groups, the patients were subdivided into four groups (group A: size 5 cm). RESULTS: When over visual grade 3 was used as the cut-off grade for the diagnosis of breast cancer, the sensitivity and specificity were 75.5, 86.4%, respectively. Early L/N of malignant breast disease was significantly higher than that of benign (2.00 +/- 1.88 vs. 0.60 +/- 0.7; p < 0.01). However, delayed L/N and RI had no significant difference between malignant and benign breast diseases. When early L/N of 1.27 was used as the cut-off value, the sensitivity and specificity of SMM were 77.6, 83.3%, respectively. When the early L/N was added to visual grade, the area under curve (AUC) of visual + quantitative analysis (V + Q) was higher than that of visual analysis (V) alone (AUC 0.893 vs. 0.803; p < 0.01). In group A, the AUC of V + Q was higher than that of V alone (0.843 vs. 0.808; p = 0.029). In group B, the AUC of V + Q was also higher (0.913 vs. 0.781; p < 0.01). However, in groups C and D, the AUCs of V + Q and V were not different (0.926 vs. 0.915; p = 0.144: 0.663 vs. 0.570; p = 0.093). For axillary lymph node involvement, the sensitivity, specificity, and of SMM were 66.9, 70.1, and 68%, respectively. CONCLUSION: From this study, the optimal visual interpretation grades for diagnosis of breast cancer were grades 4 and 5 and cut-off value of early L/N was 1.27. Also, we found that delayed image was not required for breast cancer detection and quantitative index of early L/N provide incremental diagnostic value additive to visual analysis. Especially, when the tumor is small (size <or= 3 cm), the early L/N should be obtained for the diagnosis of breast cancer.

Breast Neoplasms↗
PubMed1975

A quantitative analysis of isotope concentration profiles and rapid transport velocities in the C-fibers of the garfish olfactory nerve.

In the olfactory nerve of the long-nosed garfish (Lepisosteus osseus), unusually well-defined isotope concentration distributions can be established with the rapid transport process. Transport velocities of two profile loci can be accurately described and a quantitative profile analysis is possible after profile normalization. Results from such studies indicate that: (1) peak amplitudes decrease exponentially as a function of distance from the olfactory mucosa according to the equation p = 2130 exp (-0.109chi); (2) the wavefront base and the peak apex loci move at rates of 221 +/- 2 and 201 +/- 4 mm/day, respectively (at 23 degrees C), revealing a peak dispersion or broadening during transport; (3) the broadening is asymmetric with material shifting to the rear of the peak; (4) plateau regions are established behind the peak with material deposited by the peak; (5) only 20% of the total radioactivity in a cut nerve reaches the nerve terminals in the rapid transport peak while 80% is deposited along the axon; (6) profile areas from cut nerves decrease and lose 15% of their activity in 20 hr, while intact nerve profiles increase 10% in 16 hr due to continued somal contribution to the profile; (7) the displacement of the wavefront base (WFB) and peak apex (PA) profile loci can be described by the functions s(WFB) = (0.055T - 0.345)t - 1.43 s(PA) = (0.053T - 0.391)t - 2.71 (8) transport velocities are linear functions of temperature between 10 and 25 degrees C and increase 370% in that range. A linear extrapolation of the WFB and PA functions to 37 degrees C yields 410 and 377 mm/day, respectively.

Animals↗
PubMed1982

Quantitative analysis of procarbazine, procarbazine metabolites and chemical degradation products with application to pharmacokinetic studies.

Quantitative analytical methods are described for the analysis of the anticancer drug procarbazine and eight known metabolites including those known to have cytotoxic activity. A direct sample insertion mass spectrometric assay for procarbazine and the urinary excretion product, N-isopropyl-terephthalamic acid, has been developed. This method employs stable isotope labeled variants in a procedure that minimizes analytical errors that may be encountered in the quantitation of the chemically unstable parent drug. a liquid chromatographic method is described for the analysis of seven known procarbazine metabolites. Use of these methods is demonstrated by the analysis of procarbazine metabolism during incubation in a 9000-g rat liver homogenate preparation. Procarbazine disappearance and metabolite appearance are also monitored in rat plasma following intraperitoneal administration of a 150 mg/kg bolus dose. Applications to patient pharmacokinetics is demonstrated using the liquid chromatographic assay to follow the appearance of active procarbazine metabolites on the first and fourteenth day of an oral 250 mg/kg/day course of therapy of a patient being treated for cancer.

Animals↗
PubMed2003

Cortical orofacial motor representation in Old World monkeys, great apes, and humans. I. Quantitative analysis of cytoarchitecture.

Social life in anthropoid primates is mediated by interindividual communication, involving movements of the orofacial muscles for the production of vocalization and gestural expression. Although phylogenetic diversity has been reported in the auditory and visual communication systems of primates, little is known about the comparative neuroanatomy that subserves orofacial movement. The current study reports results from quantitative image analysis of the region corresponding to orofacial representation of primary motor cortex (Brodmann's area 4) in several catarrhine primate species (Macaca fascicularis, Papio anubis, Pongo pygmaeus, Gorilla gorilla, Pan troglodytes, and Homo sapiens) using the Grey Level Index method. This cortical region has been implicated in the execution of skilled motor activities such as voluntary facial expression and human speech. Density profiles of the laminar distribution of Nissl-stained neuronal somata were acquired from high-resolution images to quantify cytoarchitectural patterns. Despite general similarity in these profiles across catarrhines, multivariate analysis showed that cytoarchitectural patterns of individuals were more similar within-species versus between-species. Compared to Old World monkeys, the orofacial representation of area 4 in great apes and humans was characterized by an increased relative thickness of layer III and overall lower cell volume densities, providing more neuropil space for interconnections. These phylogenetic differences in microstructure might provide an anatomical substrate for the evolution of greater volitional fine motor control of facial expressions in great apes and humans.

Aged↗
PubMed1995

Quantitative analysis of the immune cells in the anal mucosa.

The prevalence of anoperineal diseases, i.e. sexual transmitted infections, is increasing particularly in AIDS, a fact which is likely due to the alteration of mucosal immunity. However, no data were available on normal anal status. In order to study anal immunity in man, we characterized lymphocytes subtypes and Langerhans' cells (LC) using quantitative morphometric analysis and immunohistochemistry. Anal normal mucosal samples obtained from surgical specimens of 45 patients (30 suffering from hemorrhoids and 15 from fissurations) were analyzed. Immunohistochemistry was performed on frozen sections with antibodies recognizing CD1a (LC), CD3 (T lymphocytes), CD4 (T4), CD8 (T8) and CD22 (B-lymphocytes). Immunostained cells were counted per square millimeter of mucosal epithelium. The surface of CD1a cells was measured using a computerized software program and a percentage of CD1a immunostained area was calculated in comparison to the whole mucosal surface. LC and T-Lymphocytes were found in the squamous epithelium in all analyzed samples. The mean values of LC number were 84.13 +/- 9.6 and 64.77 +/- 9.8 in hemorroid- and fissure-patients, respectively. The mean values of LC area (% of CD1a stained area over total mucosal surface) were 3.89 +/- 0.44 and 4.84 +/- 0.64, respectively. In the two groups, the number of intraepithelial CD8 lymphocytes was higher than that of CD4 lymphocytes. These data suggest for the first time that anal mucosa could be considered as a part of MALT system.

Adult↗
PubMed1975

Quantitative analysis of triclocarban in blood.

A method is presented for quantitatively determining triclocarban in blood. Triclocarban is extracted from blood with ether, isolated by TLC, and measured through its UV absorption at 265 nm in methanol. This method is sensitive to 250 ng (50 ppb in 5 ml of blood) of free triclocarban with a relative standard deviation of 5.2%, correlated with a radiotracer analysis of 14C-labeled triclocarban. It has been applied successfully to the analysis of triclocarban in human and rabbit blood.

Animals↗
PubMed2000

Quantitative analysis of valvular lesions during Bartonella endocarditis.

Cardiac valve pathology was evaluated in 15 patients with confirmed diagnosis of Bartonella endocarditis. Ten were infected by Bartonella quintana and 5 by Bartonella henselae. Histologic features of these cases, including fibrosis, calcification, vegetation, pattern of inflammation, and vascularization, were compared with those of valves from 25 cases of non-Bartonella endocarditis as controls using a computerized quantitative image analysis. Pathologic and immunohistologic testing for localization of Bartonella species in resected valves included Warthin-Starry stain and polyclonal antibody-based immunodetection. Compared with other cases of infective endocarditis, cases of Bartonella endocarditis are more fibrotic and calcified, less vascularized, with less extensive vegetation and chronic inflammation. These pathologic changes are suggestive of a prolonged infection. Warthin-Starry stain and immunohistologic testing demonstrated the presence of the organism, respectively, in 11 and 10 of the 13 tested valves. Results of both staining methods showed microorganisms in extracellular locations and in regions unaccompanied by inflammation. Pathology and immunohistology may contribute to the etiologic diagnosis of Bartonella endocarditis when serology and molecular techniques are not available.

Adult↗
PubMedDate not supplied

A comparison of traditional and quantitative analysis of acid-base and electrolyte imbalances in horses with gastrointestinal disorders.

The purpose of this study was to compare traditional and quantitative approaches in analysis of the acid-base and electrolyte imbalances in horses with acute gastrointestinal disorders. Venous blood samples were collected from 115 colic horses, and from 45 control animals. Horses with colic were grouped according to the clinical diagnosis into 4 categories: obstructive, ischemic, inflammatory, and diarrheic problems. Plasma electrolytes, total protein, albumin, pH, pCO2, tCO2, HCO3-, base excess, anion gap, measured strong ion difference (SIDm), nonvolatile weak buffers (A(tot)), and strong ion gap were determined in all samples. All colic horses revealed a mild but statistically significant decrease in iCa2+ concentration. Potassium levels were mildly but significantly decreased in horses with colic, except in those within the inflammatory group. Additionally, the diarrheic group revealed a mild but significant decrease in Na+, tCa, tMg, total protein, albumin, SIDm, and A(tot). Although pH was not severely altered in any colic group, 26% of the horses in the obstructive group, 74% in the ischemic group, 87% in the inflammatory group, and 22% in the diarrheic group had a metabolic imbalance. In contrast, when using the quantitative approach, 78% of the diarrheic horses revealed a metabolic imbalance consisting mainly of a strong ion acidosis and nonvolatile buffer ion alkalosis. In conclusion, mild acid-base and electrolyte disturbances were observed in horses with gastrointestinal disorders. However, the quantitative approach should be used in these animals, especially when strong ion imbalances and hypoproteinemia are detected, so that abnormalities in acid-base status are evident.

Acid-Base Imbalance↗
PubMed2006

Conformational differences in protein disulfide linkages between normal hair and hair from subjects with trichothiodystrophy: a quantitative analysis by Raman microspectroscopy.

Raman spectra of normal hair shafts and hair shafts from patients exhibiting trichothiodystrophy (TTD) were obtained using line focus laser illumination. Because hair from TTD patients has a significant decrease in the content of the sulfur-containing amino acids in comparison to normal hair, the 550-500 cm(-1) disulfide stretching mode region of the Raman spectrum was examined in detail. A quantitative spectral analysis demonstrates significant increases in the two energetically less favored gauche-gauche-trans (g-g-t) and trans-gauche-trans (t-g-t) forms. These observations suggest that the increased amounts of these less stable disulfide conformers are contributing factors to or associated with the hair brittleness observed for this congenital disorder. Structure-spectra correlations for the three dominant disulfide conformers are confirmed by quantum chemical calculations using modern density functional theory (DFT).

Biopolymers↗
PubMed1999

Quantitative analysis of povidone (PVP) in drug-PVP matrix using multicomponent analysis.

A method for the quantification of povidone (PVP), in solid dispersions and physical mixtures of the polymer and a very slightly soluble drug substance, has been developed by multicomponent analysis using the concepts of chemometrics. Because the UV-absorbance spectra of PVP is completely overlapped by the UV-absorbance spectra of the drug substance, a direct spectrophotometric method of PVP is impossible. However, UV-spectrophotometric data were analyzed by the Quant + Perkin Elmer software for quantitative multicomponent analysis using chemometrics, and by the optimal method developed using a solvent of pH 7.4, a fast, reliable, and precise detection of PVP was obtained when the content of PVP in the powder sample exceeded 20% (m/m). Two methods were developed by the calibration procedure, using buffers of pH 7.4, respectively pH 8.5. By applying a solvent of pH 8.5, more sample could be taken into use because of the enhanced solubility of the drug substance, and hence it was believed that as more PVP was taken into use, a better prediction of PVP would be obtained. However, as more drug substance was taken into use the UV-absorbance spectrum of PVP was even more overlapped, and an inferior prediction was obtained.

Calibration↗
PubMedDate not supplied

Quantitative analysis of the yeast proteome by incorporation of isotopically labeled leucine.

Quantitative comparison of protein expression levels in 2D gels is complicated by the variables associated with protein separation and mass spectrometric responses. Metabolic labeling allows cells from different experiments to be mixed prior to analysis. This approach has been reported for prokaryotic cells. Here, we demonstrate that metabolic labeling can also be successfully applied to the eukaryote Saccharormyces cerevisiae. Yeast leucine auxotrophs grown on synthetic complete media containing natural abundance Leu or D10-Leu were mixed prior to 2D gel separation and MALDI analysis of the digested proteins. D10-Leu labeling provided an effective internal calibrant for peptide MS analysis, and the number of Leu residues yielded an additional parameter for peptide identification at low mass resolution (1000). Metabolic incorporation of D10-Leu into yeast proteins was found to be quantitative since the intensities of the peptide peaks corresponded to those expected on the basis of the percent label in the media. Thus, D10-Leu labeling should provide reliable data for comparing proteomes both quantitatively and qualitatively from wild-type and nonessential-gene-null-mutant strains of S. cerevisiae. Given the central role played by yeast in our understanding of eukaryotic gene and protein expression, it is anticipated that the quantitative expressional proteomic method outlined here will have widespread applications.

Electrophoresis, Gel, Two-Dimensional↗
PubMed1984

Quantitative analysis of rotating gamma camera thallium-201 scintigrams of myocardium.

Detection of defects in myocardial uptake of thallium-201 has been investigated by tomography with a rotating gamma camera. Twenty patients, 17 of whom had symptoms suggestive but not diagnostic of angina, and three with definite angina, underwent exercise ECG testing. Thallium-201 was injected at peak stress, followed by tomographic imaging with 180 degree data collection. A repeat study 4 h later showed the resting blood flow (redistribution) pattern. Transverse, coronal and sagittal sections were reconstructed and stress and redistribution studies compared. Quantitative comparison of T1-201 uptake in the stress and redistribution sections was investigated using profile analysis. These results were compared with a visual assessment. Tomographic images clearly showed defects in myocardial uptake and enabled scans to be classified definitely as normal, ischaemic or showing previous myocardial infarction. Results agreed with those from exercise ECG where ECG findings were definite, and gave a clear diagnosis in cases with equivocal ECG results. Significant differences were demonstrated between stress and resting uptake profiles for all segments judged ischaemic on stress from the images alone. A 'normal' profile was obtained to permit identification of infarcted regions. While quantitative analysis enabled the tomograms to be classified objectively, qualitative assessment was equally effective in nearly every case, possibly due to the clear and unconfusing image presentation.

Angina Pectoris↗
PubMed2002

Quantitative analysis of a MDR1 transcript for prediction of drug resistance in acute leukemia.

BACKGROUND: Assessing the drug resistance of leukemic cells is important for treatment of leukemia. We developed a quantitative reverse transcription (RT)-PCR method for multidrug resistance 1 (MDR1) and multidrug resistance-related protein 1 (MRP1) transcripts to evaluate drug resistance, and applied it to clinical samples. METHODS: The cutoffs for copy numbers of MDR1 and MRP1 transcripts were defined based on copy numbers in healthy bone marrow mononuclear cells. To confirm that the cutoffs reflected biological resistance, we established vincristine (VCR)-resistant K562 sublines that showed various degrees of drug resistance and examined the correlation between the copy numbers of these transcripts and the biological resistance of these clones. In addition, we compared the sensitivity and specificity of quantitative RT-PCR to a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometric (FCM) analysis. RESULTS: The defined cutoff for copy numbers of MDR1 transcripts corresponded with the degree of biological resistance of VCR-resistant K562 sublines. Clinical study revealed that the concentrations of MDR1 mRNA in all relapsed patients with acute myelogenous leukemia (AML) were above the cutoff. Moreover, both AML and acute lymphoblastic leukemia patients with high MDR1 mRNA expression at diagnosis tended to show a low remission rate and short remission periods. No association was observed between the amounts of MRP1 transcripts and clinical outcomes. The specificity and sensitivity of quantitative RT-PCR for MDR1 were superior to the MTT assay and FCM analysis. CONCLUSION: These results suggest the efficacy of this quantitative analysis of MDR1 transcripts for the prediction of clinical drug resistance in acute leukemia.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1991

[Quantitative analysis of myocardial fibrosis in myocardial biopsies--a comparison between computer analysis and point counting method].

To select an appropriate method to analyze quantitatively myocardial fibrosis in myocardial biopsies, two methods, the computer analysis and the point-counting method observed at magnifications of x200 and x400, were compared. Our targeted points of examination were the accuracy and reproducibility of these methods. Twenty patients (10 with dilated cardiomyopathy and 10 with hypertrophic cardiomyopathy) were randomly selected, and the percent area of myocardial fibrosis in myocardial biopsies obtained from the right ventricular septum was measured by both the computer analysis and the point-counting method. Two observers measured the same area twice on the different days, independently. In the area of analysis, the endocardium was excluded to avoid the observer's bias. By comparing the data obtained from two observers, it was shown that the point-counting method tended to give a larger mean value and standard deviation than the computer analysis method, but that the latter indicated better reproducibility than the former. Our result showed that the degree of myocardial fibrosis varied according to methods of analysis and observer's experiences. It is recommended that the comparison of myocardial fibrosis should be made only when the methods of analysis of fibrosis are identical.

Cardiomyopathy, Dilated↗
PubMed2002

Quantitative analysis of gene expression by reverse transcription polymerase chain reaction and capillary electrophoresis with laser-induced fluorescence detection.

There has been a dramatic expansion of DNA sequence information compiled over the past several years for a variety of eukaryotic and prokaryotic genomes. Accompanying this increase in knowledge of genomic structure and organization has been a growing interest in studying the function of individual genes including regulation of their expression. A number of methods such as Northern blotting, ribonuclease protection assay, and hybridization arrays have been developed to analyze gene expression at the transcriptional (mRNA) level. Although quantitative estimates of mRNA transcripts can be obtained from each of these methods, oftentimes they lack sufficient sensitivity or the methodology is too costly or too labor-intensive to be applied to the analysis of a large number of samples. The most sensitive method for analyzing gene expression at the mRNA level involves the combination of reverse transcription and polymerase chain reaction (RT-PCR). However, in order to provide accurate quantitative estimates of gene expression, a rapid and efficient method is required for separation and detection of the double-stranded DNA (dsDNA) products of RT-PCR. Recent advances in capillary electrophoresis with laser-induced fluorescence detection (CE/LIF) have made this method suitable for the automated analysis of large numbers of RT-PCR samples. An overview of the application of CE/LIF to quantitative analysis of gene expression by RT-PCR is presented along with selected protocols and examples. Both relative-quantitative (RQ) and quantitative-competitive (QC) approaches to RT-PCR are discussed in conjunction with the use of CE/LIF for rapid and accurate quantitative analysis of PCR products.

Animals↗