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PubMed1987

Quantitative analysis of hydroxyurea and urea by proton nuclear magnetic resonance (NMR) spectroscopy.

Quantitative 1H-nuclear magnetic resonance (NMR) procedures are described for measuring hydroxyurea and urea. Dimethylsulfoxide-d6 is used as the solvent for both assays; the internal standards employed are urea and p-dichlorobenzene for hydroxyurea and urea, respectively. The analysis for hydroxyurea is based on the comparison of the area of the -NH2 peak of hydroxyurea with the area of the urea -NH2 peak area. The analysis of urea is based on the comparison of the -NH2 peak of urea with the area of the p-dichlorobenzene singlet. The 1H-NMR assays yield results that are precise and agree well with results of the more cumbersome and less specific USP procedures.

Hydroxyurea↗
PubMed2003

Quantitative analysis of pleural fluid cell-free DNA as a tool for the classification of pleural effusions.

BACKGROUND: Recently, much interest has been focused on the quantification of DNA in miscellaneous body fluids. In this study, the application is extended to classifying pleural effusions by measuring cell-free DNA in pleural fluid. METHODS: We recruited 50 consecutive patients with pleural effusions with informed consent. Pleural fluids were centrifuged at 13000 g, with supernatants aliquoted for extraction and analysis of beta-globin DNA sequence by quantitative real-time PCR. Serum and pleural fluid biochemistries were performed to classify pleural effusions using the modified criteria of Light et al. (Ann Intern Med 1972;77:507-13). The ROC curve was plotted to determine the cutoff DNA concentration for classifying pleural fluids as transudates or exudates. Indicators of diagnostic accuracy were calculated for both pleural fluid DNA and modified criteria of Light et al., using the discharge, microbiologic, and histologic diagnoses as the reference standard. RESULTS: The area under the ROC curve was 0.95 [95% confidence interval (CI), 0.84-0.99]. At 509 genome-equivalents/mL, pleural fluid DNA alone correctly classified 46 of 50 pleural effusions with 91% sensitivity (95% CI, 76-98%), 88% specificity (95% CI, 64-98%), and positive and negative likelihood ratios of 7.7 (95% CI, 3.1-19.5) and 0.10 (95% CI, 0.04-0.27), respectively. With the modified criteria of Light et al., 43 of 50 pleural effusions were correctly classified with 97% sensitivity (95% CI, 91-100%) and 67% specificity (95% CI, 45-89%). There were significant correlations between cell-free DNA and both lactate dehydrogenase and total protein in pleural fluid, suggesting their common origin. CONCLUSIONS: Pleural fluid DNA concentrations are markedly increased in exudative effusions, making it a potential new tool to evaluate the etiologic causes of pleural effusions.

Adolescent↗
PubMed2003

Quantitative analysis of global veterinary human resources.

This analysis of global veterinary personnel was based on the available quantitative data reported by individual countries to international organisations. The analysis begins with a time series of globally reported numbers of veterinarians, starting in the year 1959 (140,391). In 2000 this number reached 691,379. Of this total, 27.77% of veterinarians were working as government officials, 15.38% were working in laboratories, universities and training institutions and 46.33% were working as private practitioners. The ratio of veterinarians to technicians was 1:0.63. The global average of resources serviced by each veterinarian was as follows: 8,760 inhabitants; 189 km2 of land area and 20 km2 of arable land; 1,925 cattle, 242 buffaloes, 87 horses, 1,309 pigs, 1,533 sheep and 20,714 chickens; in abattoirs: 401 slaughtered cattle, 699 slaughtered sheep and 1,674 slaughtered pigs; the production of 336 tonnes (t) of meat, 708 t cow milk and 74 t hen eggs; in international trade: 12 cattle, 23 sheep, 22 pigs, 1 horse, 1,086 chickens, 33 t meat and meat products; 2,289 units of livestock (50 minutes of annual veterinary working time for each unit). These averages were also analysed according to employment categories. The author also discusses factors influencing veterinary personnel analyses and planning.

Animal Husbandry↗
PubMed1990

[Surface integral maps, their characteristics and methods of quantitative analysis].

Integral maps (IM) enable considerable reduction of measured data with preservation of all characteristics of electric field of the heart with exception of the time sequence of activation. Review article offers a definition of the term IM and explains the mode of their construction, depiction and analysis as well as the principles of derivation and variation maps. A review of qualitative and quantitative parameters used in analysis of IM in humans is given. There are also mentioned modes of comparison of IM from simple, directly readable parameters to complicated mathematical and statistical methods of processing.

Electrocardiography↗
PubMed1971

Electron microscope examination of subcellular fractions. 3. Quantitative analysis of the microsomal fraction isolated from rat liver.

Rat liver microsomes and microsomal subfractions isolated by density equilibration were submitted to a quantitative morphological and biochemical analysis. The total area of the endoplasmic reticulum was estimated at 7.3 m(2) per g of liver. The microsome fraction contained 2.8 mg of phospholipids and 6.7 mg of proteins per m(2) of membrane area. After correction for ribosomal and intracisternal proteins, the latter value was lowered to 4.7 mg of membrane protein per m(2). More than half of the microsomal vesicles carried ribosomes. After density equilibration of the microsomes, the distribution pattern of ribosomes followed closely that of RNA. The ribosome load of the microsomal vesicles increased steadily along the density gradient, indicating the existence of a continuous spectrum of microsomal entities ranging from entirely ribosome-free vesicles to vesicles heavily coated with ribosomes.

Animals↗
PubMed1976

Quantitative analysis of the action of Taka-amylase A on maltotriose.

The action of Taka-amylase A from Asp. oryzae was studied quantitatively by the product analysis method using unlabeled maltotriose and maltotriose labeled at the reducing end as substrates. It was found that the ratio of the unlabeled products, maltose (G2) and glucose (G1) exceeded unity, and that the ratio of the labeled products, G2/G1 was strongly dependent on the initial substrate concentrations. The results can only be explained by a transglycosylation or condensation mechanism or both. Analysis of maltose labeled at the nonreducing or reducing end reveal that the ratio of the transglycosylation to the condensation mechanism was about 20:1 with about 80 mM maltotriose. A computer simulation was made on a reaction scheme involving the termolecular-shifted complex, transglycosylation and condensation besides hydrolysis, by using reported subsite affinities as modified by the authors. The simulation reproduced the experimental results satisfactorily.

Amylases↗
PubMed1989

Molecular biology of rotaviruses. VIII. Quantitative analysis of regulation of gene expression during virus replication.

A sensitive and quantitative solution hybridization assay recently developed in this laboratory has been applied to the study of the regulation of viral gene expression in rotavirus-infected cells. Measurement of the cumulative level of viral plus-strand (mRNA) synthesis at hourly intervals throughout the growth cycle has provided evidence for both quantitative and qualitative regulation of transcription. Qualitative control was found only when cycloheximide was used to block protein synthesis in infected cells, when transcription of four of the viral genes (genes 5, 6, 7, and 9) was independent of protein synthesis. Quantitative regulation was demonstrated by the accumulation of mRNA to much higher levels for some of the viral genes (e.g., genes 2 and 7) relative to others (e.g., genes 4 and 6). In addition to quantitative control at the level of transcription, measurement of the relative molar amounts of the various viral proteins at 6.5 h postinfection showed that their levels did not directly reflect those of their encoding RNAs, indicating the existence of translational control of gene expression in the rotavirus system. Analysis of the levels of minus strand synthesized for each viral gene showed that they were not all accumulated to the same level. The significance of this result in the light of the presumed similarities in replication strategy to that of the mammalian reoviruses is discussed.

Animals↗
PubMed1997

Quantitative analysis of macular holes with scanning laser tomography.

OBJECTIVE: The purpose of the study is to establish objective, quantitative, and reproducible three-dimensional analysis for macular holes with scanning laser tomography and to correlate measurements with visual acuity. DESIGN: The authors performed a cross-sectional, nonrandomized study. PARTICIPANTS: The authors examined 28 full-thickness macular holes of 23 patients aged 61 to 84 years. INTERVENTION: Confocal infrared imaging with scanning laser tomography using the TopSS (790 nm, 10 degrees field) three-dimensional measurements and macular hole analysis were performed. MAIN OUTCOME MEASURES: Area, depth, and volume parameters for both macular holes and rims were obtained in two ways: (1) reference plane for analysis equal to height of the retina (offset surface distance [OSD] 0) or (2) equal to height of the surrounding edematous rim of the hole (OSD user). Correlation of measurements with visual acuity and groups of macular holes was performed. Reproducibility from three image series per subject and intraobserver variability from ten measurements in four subjects were computed. RESULTS: Scanning laser tomography could detect macular hole and rim features in all subjects. Infrared images provided clinically useful information that may help explain macular hole pathophysiology. Based on quantitative, three-dimensional measurements, holes were assigned to four groups: large, small, shallow, and average. Groups varied significantly (P < 0.05) for the majority of measurements. Visual acuity correlated significantly (P < 0.05) with macular hole volume, depth, slope, and rim height with OSD user only, but not with hole area. Holes computed with OSD user were deeper and of greater volume. Reproducibility was excellent for hole area, slope, and rim area; good for hole volume and depth; variable for rim volume; and improved with OSD user. Intraobserver variability was low in each group. CONCLUSIONS: Scanning laser tomography is a reproducible three-dimensional imaging technique providing objective and quantitative clinical information in assessing, grouping, and managing macular holes. By setting the OSD to rim height, additional information of rim height and hole volume was provided and correlated with visual acuity. In addition, more reliable differences among macular hole groups were found. Axial measurements such as macular hole depth, volume, and rim height may be more important for visual acuity than hole area indicating their possible predictive value for outcome measures.

Aged↗
PubMed2006

Simultaneous qualitative and quantitative analysis of the Escherichia coli proteome: a sweet tale.

We describe a novel LCMS approach to the relative quantitation and simultaneous identification of proteins within the complex milieu of unfractionated Escherichia coli. This label-free, LCMS acquisition method observes all detectable, eluting peptides and their corresponding fragment ions. Postacquisition data analysis methods extract both the chromatographic and the mass spectrometric information on the tryptic peptides to provide time-resolved, accurate mass measurements, which are subsequently used for quantitation and identification of constituent proteins. The response of E. coli to carbon source variation is well understood, and it is thus commonly used as a model biological system when validating an analytical method. Using this LCMS approach, we characterized proteins isolated from E. coli grown in glucose, lactose, and acetate. The change in relative abundance of the corresponding proteins was measured from peptides common to both conditions. Protein identities were also determined for those peptides that were unique to each condition, and these identities were found to be consistent with the underlying biochemical restrictions imposed by the growth conditions. The relative change in abundance of the characterized proteins ranged from 0.1- to 90-fold among the three binary comparisons. The overall coverage of the characterized proteins ranged from 10 to 80%, consisting of one to 34 peptides per protein. The quantitative results obtained from our study were comparable to other existing proteomic and transcriptional profiling approaches. This study illustrates the robustness of this novel LCMS approach for the simultaneous quantitative and comprehensive qualitative analysis of proteins in complex mixtures.

Chromatography, High Pressure Liquid↗
PubMed1995

A modified method for the indirect quantitative analysis of phytate in foodstuffs.

A simple, precise, and reproducible method to quantitatively assess total phytate content in foodstuffs has been developed. After HCl extraction, samples were run through an anion-exchange column and total phytate content of the eluates was spectrophotometrically measured with the modified Wade reagent. The main changes introduced in our procedure refer to pH adjustment in the extraction, dilution, and quantitation steps (pH 0.60, 6.00, and 3.00, respectively). Furthermore, the minimal extraction time for legumes (2 h) was determined. In addition, the effect of protein content on phytate determination was tested. Phytate content directly measured in crude extracts omitting anion-exchange chromatographic purification was significantly lower (P < 0.01) than values obtained using column separation, thus demonstrating that reliable phytate assessment in foodstuffs demands the utilization of anion-exchange chromatography.

Anions↗
PubMed1998

Qualitative and quantitative analysis of hemoglobin variants by capillary isoelectric focusing.

We developed two capillary isoelectric focusing (CIEF) assays, in narrow pH gradients, with the aim of routinely separating and quantitating normal and abnormal hemoglobins (Hbs): a one-step CIEF assay where residual electroosmotic flow mobilizes the proteins during focalization, and a two-step CIEF assay where focused Hbs are mobilized by low pressure by maintaining high-voltage. The resolution of 0.10 pH unit obtained with the one-step assay allowed the separation of the Hbs A, F, S and C; but Hb A2, which represents about 2-3% of whole Hb, could not be quantitated. The better resolution of 0.02 pH unit obtained with the two-step assay allowed the separation of some Hb variants of very close isoelectric points. The reproducibility of retention times was satisfactory (C.V.<5%). Moreover, in this configuration quantitation of Hb A2, Hb F and Hb S led to a standard deviation of less than 5%, allowing the diagnosis of thalassemias. The one-step assay could be useful only for the detection of abnormal variants, while the two-step assay could be applied to the routine analysis of Hbs, with quantitation of minor fractions and presumptive identification of variants.

Electrochemistry↗
PubMedDate not supplied

Quantitative analysis of dendritic networks of Purkinje neurons during aging.

This study examined quantitative parameters of Golgi-Cox stained Purkinje dendritic networks in Fischer 344 rats of three different ages. Topological patterns of branching, metric parameters of the networks, and spine densities on terminal dendritic branches of the networks were measured and analyzed relative to age of the animals. The data suggested that the networks were topologically stable at all ages, but decreases in spine density on terminal branches, in length per terminal branch, in total length of terminal branches, and in total length of the entire network were shown. Decreases in spine density were found in cells of both older groups of rats; however, decreases in length parameters were significant only in the cells of rats in the intermediate age group.

Aging↗
PubMed1979

Quantitative analysis of mating behavior in aging male Drosophila melanogaster.

Dynamic changes in quantitative aspects of mating behavior of the male fruit fly as its life unfolds, from eclosion through maturity (peak performance) and "physiological death" (loss of fertility followed by complete loss of ability to mate), towards actual death, have been identified in this work by observations and measurements on 28 male fruit flies of the Oregon R strain studied individually. At weekly sessions from the first day of their imaginal life until their natural death, each fly was given the opportunity to mate with up to three virgin females during a one-hour period. Length of the latency period of each accomplished mating and duration of copulation were recorded. After mating the females were allowed to lay eggs for 24 hours and the number of offspring was counted 26 days later. The period between 1 and 4 weeks of age is characterized by peak and fairly constant performance: multiple matings, short latencies, long durations of copulation, and high degree of fertility (number of offspring); then a decline sets in, in some measures slower than in others, as the flies age. Large intra- and inter-individual variabilities were, however, found which obscure possible correlations between individual measures of mating ability and length of life. At the individual level, a preliminary analysis showed a good correlation (r = 0.80 and 0.79) between life span and week of last mating (onset of impotence) or week of last fertile mating (onset of sterility). At the population level it was found that a number of measures, i.e. number of remaining maters at each age, number of remaining fertile maters and total number of matings, had an age-course similar to survivorship but anticipated it by 4--6 weeks. Other measures, such as number of multiple matings and number of offspring declined with age faster than survivorship.

Aging↗
PubMedDate not supplied

Quantitative analysis of lip appearance after V-Y lip augmentation.

OBJECTIVE: To quantitatively analyze the changes in the 3-dimensional appearance of the lips after V-Y lip advancement for lip augmentation. DESIGN: A retrospective single-blinded study of patients who had a V-Y lip augmentation from January 1999 to December 2001. Standardized anterior and lateral preoperative and postoperative digital photographs of patients were analyzed using digital imaging software to quantify postoperative changes. RESULTS: There were statistically significant increases in the vertical height of the upper red lip (75%) and in the area of the upper red lip (66%). The upper and lower lip projection increased by approximately 40%. The vertical distance from the apex to the trough of Cupid's bow increased by 56.7%. CONCLUSIONS: The V-Y lip advancement for lip augmentation increases the parameters that characterize the fullness of the upper lip and enhances the vermilion "pout" and projection of the upper and lower lip. It also increases the curvature of Cupid's bow.

Adult↗
PubMed1993

Quantitative analysis of mast cells in testicular aspiration cytology smears in azoospermic males.

Quantitative estimation of mast cells was done in testicular aspiration cytology smears of 90 azoospermic males. Cases included normal spermatogenesis (32), Sertoli cell only (38), late maturation arrest (16), and early maturation arrest (4). The pooled number of mast cells in 20 standard fields in Sertoli cell only and late maturation arrest cases were significantly higher than that of normal spermatogenesis (P < .001 and P < .01 respectively). Aggregates of mast cells were found around the seminiferous tubules in Sertoli cell only cases. The findings suggest that increased number of mast cells may be the cause or effect of testicular damage in idiopathic male infertility.

Biopsy, Needle↗
PubMed1986

Quantitative analysis of the cervical spinal canal by computed tomography.

Computed tomography measurements of the AP diameter, width, and cross-sectional area of the bony cervical canal were derived from cervical spine examinations of fifty-two normal adults. These quantitative parameters were then used to evaluate 80 patients with various cervical abnormalities to determine the clinical usefulness of the measurements. With the exception of spinal stenosis, quantitative cervical canal analysis was found to be of limited usefulness since normal measurements frequently occurred in the presence of significant cervical pathology.

Adolescent↗
PubMed1987

The use of iodine staining for the quantitative analysis of lipids separated by thin layer chromatography.

The method described for quantitative estimation of lipids separated on thin layer chromatography plates exploits the observation that most lipids can be stained by iodine vapor and that, in "controlled" conditions, the intensity of this staining is proportional to the actual amount of lipid in the spot. The method consists of exposing the developed plate to iodine vapor; spraying it with a suitable solvent to prevent halogen evaporation; collecting the stained lipids by scraping the spots off the plate; and determining by a rate-sensing method the absorbed iodine. The final determination is performed by measuring spectrophotometrically (at 410 nm) the rate of decolorization of a solution of Ce(IV) by As(III) in strong acidic conditions. The reaction rate, which is positively related to the concentration of iodine, is derived from the slope of the absorbance change plotted vs time. Providing that standards and samples are stained simultaneously, a quantitative estimation of lipid components of a mixture is possible in a reasonable time with excellent accuracy and reproducibility. In our hands, the method has been successfully applied to several common phospholipids, long chain fatty acids, cholesterol and deoxycholate, and triacylglycerols, in the range of 5-60 micrograms.

Amniotic Fluid↗
PubMed1987

Quantitative analysis of dendrites from transplanted neostriatal neurons.

Dendritic spine density was determined quantitatively in 35-day-old neostriatal transplants and age-matched control tissue. Transplanted spiny I neurons showed significant decreases in spine density and in number of proximal dendrites. These differences may be due to aberrant maturation of transplanted neurons.

Animals↗