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PubMed1992

The contents of macromolecule solutes in flexor tendon sheath fluid and their relation to synovial fluid. A quantitative analysis.

The importance of synovial environment for minimal adhesion formation in flexor tendon healing has recently gained attention. Various techniques have been used to restore an injured synovial tendon sheath. Therefore a quantitative analysis of flexor tendon sheath fluid is of interest to increase our knowledge about the specific synovial milieu and to evaluate the success of different types of sheath reconstructions from a biochemical point of view. Samples of tendon sheath fluid from trigger digits and tendon sheaths containing ganglions have been assayed for contents of hyaluronic acid and proteins of different molecular weights. The results show concentrations of hyaluronate and several proteins similar to those in normal joint fluid. These results indicate that flexor tendon sheath fluid has a character similar to synovial fluid of joints and apparently has specific functions such as soft tissue lubrication and nutrition of avascular tendon tissue.

Adult↗
PubMed1986

Quantitative analysis of ultrastructural changes in synapses of the rat hippocampal field CA3 in vitro in different functional states.

Transverse slices (250-350 microns) of the rat hippocampus were used for estimation of quantitative correlations between the ultrastructure and function of giant spinous synapses localized in stratum lucidum of the field CA3. Spontaneous and evoked spike discharges were used to determine the following five functional states of the neurons: "control"; "depletion" was achieved by long-term continuous stimulation (30-50 Hz for 1 h and longer); "recovery" when the slices rested after "depletion" till the evoked response was recovered; long-term potentiation I was achieved by short-term tetanic stimulation (5-15 s, 50-70 Hz); long-term potentiation II was achieved by a similar tetanic stimulation as for long-term potentiation I after the "recovery". For quantitative analysis of ultrastructural changes in the giant spinous synapses the following parameters were used: density of presynaptic vesicles determined as a ratio between the number of vesicles located within the giant bouton and the area of the latter (number of vesicles per 1 micron2); vesicle diameter distribution; area and length of the postsynaptic densities. A correlation of these parameters with the functional state of CA3 neurons was found. The area and length of postsynaptic densities are the most statistically significant parameters of the giant spinous synapses in different functional states. In contrast to other states, an increase in the length and the area of postsynaptic densities in long-term potentiation was found. A hypothesis on postsynaptic densities' role in long-term potentiation formation is suggested. The role of presynaptic and postsynaptic ultrastructural rearrangements is discussed as a possible mechanism determining the efficiency of synaptic transmission.

Animals↗
PubMed1985

Quantitative analysis of common anaesthetic agents.

A summary of chromatographic (e.g. gas chromatography, high-performance liquid chromatography) and non-chromatographic (e.g. radioimmunoassay, enzyme-multiplied immunoassay) analytical techniques suitable for the quantitative analysis of the most popular inhalational (halothane, methoxyflurane, enflurane, isoflurane and nitrous oxide), intravenous (barbiturate, benzodiazepines, etomidate, althesin, morphine, fentanyl, alfentanil, sufentanil, droperidol and ketamine) general and amide-type local (lidocaine, mepivacaine, etidocaine and bupivacaine) anaesthetic agents and some of their metabolites, in biological material, is described. In the case of inhalational anaesthetics attention is also payed to pollution measurement and breath-to-breath monitoring.

Air Pollutants, Occupational↗
PubMed2006

Quantitative analysis of liquid formulations using FT-Raman spectroscopy and HPLC The case of diphenhydramine hydrochloride in Benadryl.

The capability of FT-Raman spectroscopy for the fast and non-destructive quantitative analysis of liquid formulations was tested and the results were compared to those obtained by HPLC. Diphenhydramine hydrochloride (DPH), the active ingredient of Benadryl, was determined in the presence of the numerous excipients of the elixir. A Raman calibration model was developed by measuring the peak intensities of different standard solutions of DPH vibration at 1003 cm(-1). Application of the calibration model on the peak intensity recorded from the as-received commercially available sample with 2.5 mg ml(-1) DPH nominal value yielded a value of 2.49+/-0.05 mg ml(-1) DPH. The reliability of this method was verified by testing it against the conventionally used HPLC. The results from both methods were in excellent agreement. The main advantage of Raman over HPLC method during routine analysis is that is considerably faster and less solvent consuming. Furthermore, Raman spectroscopy is non-destructive for the sample. On the other hand, the detection limit for Raman spectroscopy is much higher than the corresponding for the HPLC methodology.

Anti-Allergic Agents↗
PubMed1998

Quantitative analysis and process monitoring of site-specific glycosylation microheterogeneity in recombinant human interferon-gamma from Chinese hamster ovary cell culture by hydrophilic interaction chromatography.

A chromatographic method was developed for quantitative analysis of site-specific microheterogeneity of the two N-linked glycosylation sites in recombinant human interferon-gamma produced from Chinese hamster ovary (CHO) cell culture. After the interferon-gamma was harvested by affinity chromatography, the tryptic digestion was carried out. The two glycopeptide pools, isolated from reversed-phase chromatography of tryptic digestion of interferon-gamma, were subjected to further separation by hydrophilic interaction chromatography. Each peak in the chromatograms was identified by matrix-assisted laser desorption ionization and time-of-flight mass spectrometry (MALDI-TOF-MS). The overall elution order of the glycopeptides was the following: neutral glycopeptides, monosialylated glycopeptides, bisialylated glycopeptides, trisialylated glycopeptide and tetrasialylated glycopeptides. Based on the integrated peak area for each compound in the chromatograms, the percentage for each glycan was utilized to quantify the glycosylation pattern of the interferon-gamma. Finally, sialylation and antennarity structure percentages at the two glycosylation sites were chosen as the quality indicators in process monitoring of interferon-gamma production from a serum-free suspension-batch CHO culture.

Animals↗
PubMed1999

Quantitative analysis of breast parenchymal density: correlation with women's age.

RATIONALE AND OBJECTIVES: The authors evaluated the relationship between a woman's breast parenchymal density and her age by means of a quantitative method for measuring density from digitized mammograms. MATERIALS AND METHODS: The percentage of the breast considered to be dense was evaluated from mammograms of 50 women stratified by age. Quantitative analysis based on the computer segmentation of tissue in digitized mammograms was performed by three expert mammographers. The results of this analysis were compared with results from a review of the film mammograms by three expert mammographers. RESULTS: A slight decrease in the percentage of breast considered to be dense with increased age was observed. The average difference in the percentage of dense breast tissue between the youngest and the oldest age groups was 6.4% based on the digital review and 14.6% based on the film review. Within each age group, the total variability was on the order of 75%. CONCLUSION: The difference in mean magnitude between the youngest and oldest age groups was small and may not be clinically important. The variability within an age group was large, which suggests that age is not a reliable indicator of percentage of dense breast tissue.

Adult↗
PubMed2000

New insights into the metabolic consequences of large-scale mtDNA deletions: a quantitative analysis of biochemical, morphological, and genetic findings in human skeletal muscle.

In order to study putative genotype phenotype correlations in mitochondrial disorders due to large-scale mtDNA deletions we performed a quantitative analysis of biochemical, morphological, and genetic findings in 20 patients. The size of the mtDNA deletions varied from 2 to 7.5 kb with a degree of heteroplasmy ranging from 16% to 78%. Applying improved methods for measuring respiratory chain enzyme activities, we found highly significant inverse correlations between the percentage of cytochrome c oxidase (COX)- negative fibers and citrate synthase (CS) normalized COX ratios. Significant correlations were also established between CS normalized complex I and complex IV ratios as well as between the degree of heteroplasmy of mtDNA deletions and the percentage of ragged red fibers, COX-negative fibers, and CS normalized complex I and complex IV ratios. Our results indicate that the degree of heteroplasmy of mtDNA deletions is mirrored on the histological as well as the biochemical level. Furthermore, our findings suggest that single large-scale deletions equally influence the activities of all mitochondrially encoded respiratory chain enzymes. Even low degrees of heteroplasmy of mtDNA deletions were found to result in biochemical abnormalities indicating the absence of any well-defined mtDNA deletion threshold in skeletal muscle.

Adolescent↗
PubMed2001

Quantitative analysis of x-ray absorption near edge structure data by a full multiple scattering procedure: the Fe-CO geometry in photolyzed carbonmonoxy-myoglobin single crystal.

We report the first quantitative analysis of the Fe K-edge polarized x-ray absorption near edge structure of the iron protein carbonmonoxy-myoglobin (MbCO) single crystal and of its cryogenic photoproduct Mb(*)CO. The CO-Fe-heme local structure has been determined using a novel fitting procedure based on the full multiple scattering approach. The extracted local structure of Mb(*)CO includes a Fe-CO distance of (3.08+/-0.07) A, with a tilting angle between the heme normal and the Fe-C vector of (37+/-7) degrees, and a bending angle between the Fe-C vector and the C-O bond of (31+/-5) degrees.

Animals↗
PubMed1991

[Quantitative analysis of hemodynamic disorders in coronary occlusion based on the roentgeno-cinematographic data].

The contrasting time of the coronary arteries in 4 types of atherosclerotic lesions was determined by means of quantitative analysis of the coronarograms. The contrasting time was found to be dependent both on the degree of the stenosis and on the condition of the distal segment of the coronary artery. The condition of the drainage tracts had a more marked effect on the contrasting time. The coronary arteries contrasting time is considered as an index of peripheral resistance in the studied segment.

Cineangiography↗
PubMed1988

[Use of the data of quantitative analysis of organo-systemic distribution of tumors in the evaluation of real hazards of chemical carcinogens].

The study was concerned with objective criteria for identification of actual carcinogenic hazards. It used quantitative analysis data on morphologic structures of tumors induced in 12565 albino noninbred rats in the course of carcinogenicity evaluation of 112 chemical agents. The totality of all the data were analyzed versus morphologic parameters of tumors and carcinogenicity of the agents. Spontaneous tumors turned to be the cause of death in animals treated with noncarcinogenic or slightly carcinogenic agents whereas a completely different spectrum of tumors were responsible for lethality in those receiving potent carcinogens. It was inferred that increased incidence of spontaneous tumors following treatment with maximum tolerable doses can not be used as a criterion of actual blastogenicity of an agent.

Adrenal Gland Neoplasms↗
PubMed2003

Direct quantitative analysis of organic compounds in the gas and particle phase using a modified atmospheric pressure chemical ionization source in combination with ion trap mass spectrometry.

A slightly modified atmospheric pressure chemical ionization source is employed for direct quantitative analysis of volatile or semivolatile organic compounds in air. The method described here is based on the direct introduction of an analyte in the gas or particle phase, or both, into the ion source of a commercial ion trap mass spectrometer. For quantitation, a standard solution is directly transferred into the vaporizer unit of the ion source via a deactivated fused-silica capillary by using the sheath liquid syringe pump, which is part of the mass spectrometer. The standard addition procedure is conducted by varying the pump rate of a diluted solution of the standard compound in methanol/water. A N2 sheath gas flow is applied for optimal vaporization and mixing with the analyte gas stream. By performing detailed reagent ion monitoring experiments, it is shown that the relative signal intensity of [M + H]+ ions is dependent on the relative humidity of the analyte gas stream as well as the composition and concentration of CI reagent ions. The method is validated by a comparison of the standard addition results with a calibration test gas of known concentration. To demonstrate the potential of atmospheric pressure chemical ionization mass spectrometry as a quantitative analytical technique for on-line investigations, a tropospherically relevant reaction is carried out in a 493-L reaction chamber at atmospheric pressure and 296 K in synthetic air at 50% relative humidity. Finally, the applicability of the technique to rapidly differentiate between analytes in the gas and particle phase is demonstrated.

Journal Article↗
PubMed2004

Qualitative and quantitative analysis of low molecular weight compounds by ultraviolet matrix-assisted laser desorption/ionization mass spectrometry using ionic liquid matrices.

A major problem hampering the use of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry for quantitative measurements is the inhomogeneous distribution of analytes and matrices in solid sample preparations. The use of ionic liquids as matrices for the qualitative and quantitative analysis of low molecular weight compounds like amino acids, sugars and vitamins was investigated. The ionic liquid matrices are composed of equimolar combinations of classical MALDI matrices (sinapinic acid, alpha-cyano-4-hydroxycinnamic acid or 2,5-dihydroxybenzoic acid) with organic bases. These matrix systems allow a homogenous sample preparation with a thin ionic liquid layer having negligible vapour pressure. This leads to a facilitated qualitative and quantitative measurement of the analytes compared with classical solid matrices.

Amino Acids↗
PubMed1979

[Quantitative analysis of yeast cell inactivation under the action of UHF radiation].

A particular case of the earlier suggested probability model of the action of electromagnetic irradiation on the cell is described. The model has been used for the quantitative analysis of inactivation forms and survival curves of yeast cells of different strains exposed by electromagnetic field of SHF-range. The results of calculation and experimental data show that the probability model is suitable for both qualitative and quantitative description of different cell responses to SHF-irradiation.

Electromagnetic Phenomena↗
PubMedDate not supplied

Quantitative analysis of polymeric proanthocyanidins in birch leaves with normal-phase HPLC.

The proanthocyanidin composition and content in the leaves of nine birch species (Betula albosinensis, B. ermanii B. maximowicziana, B. nana, B. papyrifera, B. pendula, B. platyphylla, B. pubescens, and B. pubescens ssp. czerepanovii) were studied with different methods including colorimetric assay, HPLC coupled with PAD or ESI/MS and NMR. Total proanthocyanidin content was determined using the acid butanol assay. A normal phase-HPLC method was applied for the analysis of polymeric proanthocyanidins. The content of polymeric proanthocyanidins was estimated from a late eluting peak in the chromatogram. With this HPLC method, quantitative analysis of polymeric proanthocyanidins could be performed directly from leaf extracts: no additional purification or preparation steps were required. It was shown that birch leaves contained mainly polymeric proanthocyanidins with a degree of polymerisation greater than 10. Total proanthocyanidin content (expressed as dry weight) was found to vary from 44mg/g (B. papyrifera) to 145mg/g (B. nana), and polymeric proanthocyanidin content from 39mg/g (B. pendula) to 119 mg/g (B. nana).

Betula↗
PubMed2002

Quantitative analysis of K-ras gene mutation in pancreatic tissue obtained by endoscopic ultrasonography-guided fine needle aspiration: clinical utility for diagnosis of pancreatic tumor.

OBJECTIVES: Endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) has become established in the diagnosis of pancreatic cancer. The combination of pathological diagnosis and analysis for mutant K-ras gene was investigated to improve the accuracy of diagnosis. METHODS: EUS-FNA was performed in 34 patients with pancreatic masses (26 adenocarcinomas and eight chronic pancreatitis). Mutant ras gene was analyzed semiquantitatively in the specimens obtained by EUS-FNA as well as in pancreatic juice obtained by ERCP. RESULTS: Mutant gene was detected at high amounts (more than 2% of total ras genes) in 20 of 26 (77%) specimens of EUS-FNA and in 12 of 19 (63%) of pancreatic juice in cases with pancreatic carcinoma. Cytological diagnosis of malignancy by EUS-FNA was found in 16 of 26 (62%) patients with pancreatic cancer. Accurate diagnosis of the carcinoma was 21 of 26 (81%) by combined cytology and molecular method of EUS-FNA, and increased to 23 of 26 (88%) by adding molecular analysis of pancreatic juice. In contrast, mutant gene was absent or low level despite suspicious cytology in patients with benign pancreatic lesion. CONCLUSION: Quantitative analysis of mutant ras gene supplemented conventional cytology of EUS-FNA and ERCP. Detection of mutation at high amounts may represent pancreatic cancer, whereas its absence increased the possibility of benign lesion.

Adenocarcinoma↗
PubMed1979

Quantitative analysis of methylguanidine and guanidine in physiologic fluids by high-performance liquid chromatography-fluorescence detection method.

A rapid and sensitive high-performance liquid chromatographic method has been developed for the quantitative analysis of methylguanidine and guanidine in physiological fluids. These quanidino compounds are separated on a 6 x 0.23 cm cation-exchange column with 0.5 M sodium hydroxide solution. The guanidino compounds are detected with a fluorometer, which monitors the fluorescent guanidine derivatives produced by the reaction of the eluted constituents with 9,10-phenanthrenequinone. Sensitivity to sub-nanomole levels of methylguanidine and guanidine is demonstrated. The method was successfully applied to physiological fluids such as serum and cerebrospinal fluid from uremic patients.

Chromatography, High Pressure Liquid↗
PubMed1982

Quantitative analysis of muscle biopsies from volunteers and patients with neuromuscular disorders. A comparison between estimation and measuring.

106 muscle biopsies from patients with neuromuscular diseases or symptoms were assessed by routine inspection and quantitative examination. Eighty-six specimens were classed as pathological on routine evaluation and 84 on quantitative examination. Eleven specimens that were pathological on routine evaluation were "missed' by quantitative examination. Nine judged normal on routine examination were pathological according to quantitative criteria. Relative measures including the coefficient of variance, the difference between type I and type II fibres, and the difference between fascicles proved valuable for distinguishing between normal and pathological specimens. Quantitative analysis is a valuable complementary method which improves the detection of pathological states in muscle.

Adolescent↗
PubMed1987

Quantitative analysis of cerebral vessels in the newborn puppy: the structure of germinal matrix vessels may predispose to hemorrhage.

Intracerebral hemorrhage in premature infants commonly originates in the germinal matrix (GM). We performed a quantitative analysis of cerebral microvasculature from newborn puppies, a model for neonatal periventricular and intraventricular hemorrhage, at the light and electron microscopic level. GM vessels were compared with those of other brain regions in an effort to delineate pathogenetically significant structural features that might predispose to hemorrhage. Light microscopic examination revealed that GM vessel density (103.0 vessels/mm2) was similar to that in white matter (98.3 vessels/mm2), but lower than that of cortex (155.6 vessels/mm2) or caudate (259.9 vessels/mm2). Mean blood vessel diameter was slightly larger in GM (9.0 mu) than cortex (6.9 mu), caudate (7.9 mu), and white matter (8.9 mu). Ultrastructurally, GM vessels were thinner along greater portions of their circumferences than vessels from other brain regions, as shown by their smaller ratio of vessel wall area/vessel lumen area and their greater fraction of vessel wall with thickness less than 0.25 mu. In addition, a significantly larger fraction of GM capillary wall lacked direct contact with perivascular structures. We postulate that the larger size, thinner walls, and diminished support from surrounding neuropil, which characterize GM vessels, may render them more susceptible to both physical (e.g. hypertension) and metabolic (e.g. hypoxia) insults than vessels from other brain regions.

Animals↗