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PubMed1982

Low-dose radioisotope scanning and quantitative analysis in the diagnosis of congenital hypothyroidism.

Quantitative thyroid scanning using low doses of 99mTc sodium pertechnetate (1.85-3.7 MBq) was performed in 38 cases of congenital hypothyroidism. Of these 38 cases, 29 were scanned at 14 +/- 6 days old, and 9 at 1 year old. The scans show the full range of gland anatomy from athyreotic to normal. All morphologically normal scans had grossly increased uptakes of 99mTc. The incidence of the various thyroid anatomies was different in each age group. The average radiation dose to the thyroid was 2.29 mGy, with at least 70% of patients receiving a dose of 3.0 mGy or less. Such low doses of 99mTc should allow further scanning in later life. Neonatal thyroid scanning reveals the aetiology of congenital hypothyroidism and enables the clinician to assess the short- and long-term needs of the child.

Congenital Hypothyroidism↗
PubMed1991

[A method of quantitative analysis of gentamicin sulfate].

A procedure for quantitative assay of gentamicin sulfate was developed. It is based on formation of an ionic associate with bromothymol blue followed by chloroform extraction and the photometric determination at 420-422 nm. The relative error does not exceed 0.94 and 0.98 per cent in regard to the substance and its dosage form (gynecological suppositories), respectively. Optimal conditions for the assay were elaborated i.e. the ratio of the reagent and extraction agent, the time and the number of the extractions and pH of the medium. The process obeys to the main law of light absorption within the concentration of gentamicin sulfate in aqueous solution equal to 8-128 micrograms/ml.

Bromthymol Blue↗
PubMed1981

Quantitative analysis of steroid autoradiograms.

Two types of quantitative criteria are compared that have been used to discriminate labeled and nonlabeled cells in steroid autoradiograms: multiplicative criteria factors affect the accuracy of the assessment of cell labeling, including variation in the length of exposure, variations in cell size, and possible nonlinearities in the grain density of autoradiograms as a function of exposure time. These factors have a greater effect on the accuracy of the determination of cell labeling when using multiplicative criteria, so that the Poisson criterion is more suitable.

Animals↗
PubMed1987

[Quantitative analysis of spinal cord injury using the isopotential spinal cord surface mapping].

To evaluate spinal cord injury quantitatively and qualitatively, distribution of spinal cord surface potentials were analyzed using a isopotential mapping technique. The segmental spinal evoked potential was recorded simultaneously with 21-42 silver ball electrodes applied to the dorsal and ventral surface of the lumbar spinal cord of 37 anesthetized cats. The severity of spinal cord lesion was divided into 5 grades from 100 gcf to 500 gcf according to Allen's weight drop method. An analysis of isopotential map was made up to 24 hours after trauma. The results showed that N3 which was considered as the interneuron activity projecting from the dorsal horn to the anterior horn, revealed no shift of localization. It was therefore appeared appropriate for use as a parameter for quantitative analysis, especially in subtract and variation maps. The data provided not only amplitude and latency but also two dimensional surface spreads of electricity.

Animals↗
PubMed2005

Quantitative analysis of the benefits and risks of consuming farmed and wild salmon.

Contaminants in farmed Atlantic and wild Pacific salmon raise important questions about the competing health benefits and risks of fish consumption. A benefit-risk analysis was conducted to compare quantitatively the cancer and noncancer risks of exposure to organic contaminants in salmon with the (n-3) fatty acid-associated health benefits of salmon consumption. Recommended levels of (n-3) fatty acid intake, as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), may be achieved by consuming farmed or wild salmon while maintaining an acceptable level of noncarcinogenic risk. However, the recommended level of EPA+DHA intake cannot be achieved solely from farmed or wild salmon while maintaining an acceptable level of carcinogenic risk. Although the benefit-risk ratio for carcinogens and noncarcinogens is significantly greater for wild Pacific salmon than for farmed Atlantic salmon as a group, the ratio for some subgroups of farmed salmon is on par with the ratio for wild salmon. This analysis suggests that risk of exposure to contaminants in farmed and wild salmon is partially offset by the fatty acid-associated health benefits. However, young children, women of child-bearing age, pregnant women, and nursing mothers not at significant risk for sudden cardiac death associated with CHD but concerned with health impairments such as reduction in IQ and other cognitive and behavioral effects, can minimize contaminant exposure by choosing the least contaminated wild salmon or by selecting other sources of (n-3) fatty acids.

Animals↗
PubMed1999

Quantitative analysis of alachlor protein adducts by gas chromatography-mass spectrometry.

This study examined the potential use of hemoglobin (Hb)- and serum-protein adducts of alachlor as potential biomarkers of alachlor exposure, a genotoxic and carcinogenic herbicide. The method developed was based on the observation that cleavage of S-cysteinyl alachlor-protein adducts by methanesulfonic acid gave the rearrangement product 3-(2',6'-diethylphenyl)-1, 3-thiazolidine-4-one (TZO). The structure of TZO was confirmed by mass spectroscopy, NMR spectroscopy, and independent synthesis. In the assay, treatment of alachlor-cysteinyl protein adducts by methanesulfonic acid was followed by extraction and analysis. TZO was detected and quantitated by electron-impact GC/MS in the single ion-monitoring mode. [ring-13C6]Alachlor-N-acetylcysteine was added as an internal standard prior to treatment and was converted to [ring-13C6]TZO, allowing response factors to be used to quantitate TZO concentrations. Incubations of alachlor (0-1000 microM) with human albumin and bovine serum albumin (BSA) resulted in linear adduct formation with both proteins. Maximal adduction levels of 613-1130 pmol alachlor-albumin adducts/mg protein were observed, with BSA binding close to twice that of human albumin. A linear concentration response of alachlor-Hb adducts was observed when whole blood from female CD rats was incubated with alachlor in vitro at concentrations up to 300 microM. Maximal binding was 1860 pmol alachlor-Hb adducts/mg globin. Male CD rats treated with alachlor at 150 mg/kg body wt/day ip for 0, 1, 2, and 3 days were sacrificed 4 days after final dosing. A maximal binding of 2250 pmol alachlor-Hb adducts/mg globin was observed. This assay provides a new approach for biomonitoring alachlor levels in experimental animals and has the potential for use in humans.

Acetamides↗
PubMed2005

Quantitative analysis of plasma TP53 249Ser-mutated DNA by electrospray ionization mass spectrometry.

A mutation in codon 249 of the TP53 gene (249(Ser)), related to aflatoxin B(1) exposure, has previously been associated with hepatocellular carcinoma risk. Using a novel internal standard plasmid, plasma concentrations of 249(Ser)-mutated DNA were quantified by electrospray ionization mass spectrometry in 89 hepatocellular carcinoma cases, 42 cirrhotic patients, and 131 nonliver diseased control subjects, all from highly aflatoxin-exposed regions of The Gambia. The hepatocellular carcinoma cases had higher median plasma concentrations of 249(Ser) (2,800 copies/mL; interquartile range: 500-11,000) compared with either cirrhotic (500 copies/mL; interquartile range: 500-2,600) or control subjects (500 copies/mL; interquartile range: 500-2,000; P < 0.05). About half (52%) of the hepatocellular carcinoma cases had >2,500 copies of 249(Ser)/mL plasma, corresponding to the prevalence of this mutation in liver tumors in The Gambia. In comparison, only 15% of control group and 26% of cirrhotic participants exceeded this level (P < 0.05). Further subset analysis revealed a statistically significant, quantitative relation between diagnosis of hepatocellular carcinoma and levels of 249(Ser) detected at 2,501 to 10,000 copies/mL plasma (odds ratio, 3.8; 95% confidence interval, 1.3-10.9) and at >10,000 copies/mL plasma (odds ratio, 62; 95% confidence interval, 4.7-820) when compared with control subjects and after adjusting for age, gender, recruitment site, hepatitis B and C serologic status, and total DNA concentration. Levels of >10,000 copies of 249(Ser)/mL plasma were also significantly associated with the diagnosis of hepatocellular carcinoma (odds ratio, 15; 95% confidence interval, 1.6-140) when compared with cirrhotic patients. Potential applications for the quantification of 249(Ser) DNA in plasma include estimation of long-term, cumulative aflatoxin exposure and selection of appropriate high-risk individuals for targeted intervention.

Aflatoxins↗
PubMed1990

Quantitative analysis of cytoskeletal proteins throughout the cell cycle of the MRC-5 fibroblastic cell line.

Fluorescent dyes were used to stain actin, vimentin, tubulin and DNA in the same MRC-5 fibroblastic cells. Cytofluorometry and image analysis were then used to quantitatively evaluate the F actin, vimentin and tubulin content throughout the cell cycle. The results showed that different cells can have the same DNA content while their cytoskeletal protein content is variable. The data also showed that cytoskeletal protein content variations exist throughout the cell cycle of the fibroblastic cell line. The F actin content increased during the cell cycle from G1 to G2 phases and decreased in M phase. The amount of tubulin in the G2 was about twice as much as that in the G1 phase, before decreasing in the M phase; there was a threshold of tubulin content for G2 cells entering S phase.

Actins↗
PubMed2004

Rapid, quantitative analysis of ppm/ppb nicotine using surface-enhanced Raman scattering from polymer-encapsulated Ag nanoparticles (gel-colls).

Rapid, quantitative SERS analysis of nicotine at ppm/ppb levels has been carried out using stable and inexpensive polymer-encapsulated Ag nanoparticles (gel-colls). The strongest nicotine band (1030 cm(-1)) was measured against d(5)-pyridine internal standard (974 cm(-1)) which was introduced during preparation of the stock gel-colls. Calibration plots of I(nic)/I(pyr) against the concentration of nicotine were non-linear but plotting I(nic)/I(pyr) against [nicotine](x)(x = 0.6-0.75, depending on the exact experimental conditions) gave linear calibrations over the range (0.1-10 ppm) with R(2) typically ca. 0.998. The RMS prediction error was found to be 0.10 ppm when the gel-colls were used for quantitative determination of unknown nicotine samples in 1-5 ppm level. The main advantages of the method are that the gel-colls constitute a highly stable and reproducible SERS medium that allows high throughput (50 sample h(-1)) measurements.

Nanostructures↗
PubMed1995

Quantitative analysis of solitary lesions of bone.

RATIONALE AND OBJECTIVES: To quantitate the radiographic features of common solitary lesions of bone using vector analysis to optimize their radiographic description. METHODS: Plain radiographs of 709 solitary bone lesions were reviewed. Relevant demographic, anatomic, and structural data were cataloged. These data were used to approximate the vector space defined by all possible solitary lesions of bone. Vector space analysis on the entire set of lesions was performed to determine similarities among and between lesion types. RESULTS: The 709 lesions generated 614 separate vectors within the appearance vector space. Only 10 vectors were represented more than 3 times, indicating great variability among and between most lesion types. Osteochondromas (with two vectors repeated 10 and 15 times, respectively) and peripheral chondrosarcomas (with one vector repeated 5 times) were relatively uniform in appearance. Gender bias was present for multiple types of lesions. Larger lesions that involved more than one anatomic center were more likely to be malignant. Lesions occurring in the femoral diaphysis and pelvic flat bones were statistically more likely to be malignant. CONCLUSIONS: Analysis shows that most lesions have highly varied vectors in the appearances within the vector space. More in-depth analysis of each lesion type using this quantitative technique is required to better define individual lesion subspaces and hence their radiographic appearances with respect to other bone lesions.

Bias↗
PubMed1991

Dot-blot hybridization: quantitative analysis with direct beta counting.

The suitability of using direct beta counting (DBC) for quantitating radioactivity of the probe:target complex in dot-blot hybridization was evaluated using a Packard Matrix 96. A comparison of blots analyzed using autoradiography followed by densitometry scanning (film/densitometry) with those analyzed using direct beta counting revealed similar data trends with the two methods. However, direct beta counting quantitated the amount of radioactivity in the dot blots directly (without film exposure or additional sample preparation), which significantly reduced the time required to obtain results. Blots analyzed first with direct beta counting and then liquid scintillation counting exhibited similar data trends with both methods. Despite a decreased counting efficiency, analysis with direct beta counting has the following advantages compared with liquid scintillation counting: 1) no additional sample preparation is required (no vials or cocktail are used), 2) no sample destruction occurs due to analysis and 3) quantitative results are obtained more rapidly (since the radioactivity for all 96 samples in a dot blot is simultaneously determined in real time). Analysis with direct beta counting was also shown not to interfere with the successful reprobing of stripped dot blots with either unique sequence or total genomic probes. Overall, direct beta counting provides quick, quantitative results for dot blots while saving considerable time and effort.

Animals↗
PubMed2002

Quantitative analysis of a model opioid peptide and its cyclic prodrugs in rat plasma using high-performance liquid chromatography with fluorescence and tandem mass spectrometric detection.

Two analytical methods were developed for quantitative determination of DADLE (H(2)N-Tyr-D-Ala-Gly-Phe-D-Leu-COOH) and its two cyclic prodrugs in rat plasma. For high-performance liquid chromatography with fluorescence detection (LC-FLU), precolumn derivatization of DADLE was accomplished by labeling the N-terminal amino group with the reagent naphthalene-2,3-dicarboxaldehyde in the presence of cyanide (NDA/CN) to form a highly fluorescent 1-cyanobenz[f]isoindole (CBI) derivative. A multi-dimensional LC system was employed to improve selectivity, and solid-phase extraction (SPE) was used for plasma sample preparation. The cyclic prodrugs were converted to DADLE prior to their derivatization. With fluorescence detection after derivatization, the limit of quantitation (LOQ) was 6 ng ml(-1) for the analysis of DADLE, and good linearity was observed up to 6000 ng ml(-1) in rat plasma. Quantitative analysis of DADLE and its cyclic prodrugs was also performed using liquid chromatography interfaced to electrospray ionization tandem mass spectrometry (LC-ESI-MS-MS). Chromatographic separation was achieved on a C(18) column using gradient elution in a water-acetonitrile system containing 0.1% (v/v) formic acid. The tandem mass spectrometric analysis was performed in the multiple reaction monitoring mode using internal standardization to improve assay precision and accuracy. For plasma sample pretreatment, acetonitrile was added first to precipitate proteins and SPE was used to minimize matrix effects. Using LC-ESI-MS-MS, the LOQ was 0.5 ng ml(-1) for DADLE and 2 to 5 ng ml(-1) for its prodrugs. Good linearity was observed from the LOQ up to 1000 ng ml(-1) for all compounds. For the analysis of DADLE, both analytical methods showed good precision, accuracy and stability. However, for prodrug analysis, LC-FLU showed some sensitivity and accuracy problems, while the LC-ESI-MS-MS method provided consistent and satisfactory results. In conclusion, LC-ESI-MS-MS is the method of choice for the analysis of DADLE and its cyclic prodrugs in rat plasma samples due to its good selectivity, high sensitivity, and fast analysis. Its application was demonstrated through biodisposition and bioconversion studies of the coumarinic acid-based prodrug after intravenous administration in rats.

Animals↗
PubMed2000

Quantitative analysis of neutral body posture in prolonged microgravity.

The experiment was performed during a 6-month space flight and focused on the quantitative three-dimensional description of the Neutral Body Posture (NBP) and of subjects' spine anthropometry in Erect Posture (EP). The NBP joint angles' configuration is described along the long-term microgravity exposure and compared with respect to previous in-flight collected data. Observed spinal length modification during EP in-flight is related to on-ground investigations focused on circadian anthropometrical fluctuations. The flattening of the spinal lumbar lordosis and thoracic kyphosis is also described. Even though only two subjects were studied, this analysis points out the maturity of the opto-electronic technology for the quantitative analysis of posture in microgravity and confirms the need of enriching the anthropometrical database of human postures in weightlessness for the design optimization of permanently inhabited space modules.

Adult↗
PubMedDate not supplied

Quantitative analysis of age-related dendritic changes in medium spiny I (MSI) striatal neurons of C57BL/6N mice.

Our study used quantitative morphometric analysis and Golgi staining methods to evaluate postnatal changes in the dendritic architecture of MSI neurons of the striatum between 1 and 30 months of age. Morphological changes and chronological age were also correlated with functional testing in order to identify subpopulations of aged mice with dendritic alterations that may be more characteristic of a motor deficit rather than the normal aging process. We found that the overall size of the dendritic arbor of MSI neurons in the rostral striatum remained stable with age, while caudal MSI neurons exhibited a significant elongation of terminal dendritic segments between 25 and 30 months of age. In addition, our correlation analysis of motor performance and chronological age found that neither striatal-motor deficits nor their associated anatomical correlates were inevitable consequences of senescence but were characteristic for a select subpopulation of aged mice with striatal-motor deficits. We found that mice that tested poorly on the balance rod had a significant increase in the number of MSI neurons with small dendritic arbors in various stages of atrophic degeneration. Conversely, 30-month-old mice that had no functional impairment showed no significant change in the number of neurons with atrophic dendrites. These data reinforce the premise that the correlation of structure and function plays an important role in the analysis of an aging population since data may vary based on the number of functionally impaired or unimpaired mice that make up an experimental group.

Age Factors↗
PubMed1997

Densitometric quantitative analysis of intracoronary ultrasound images: anatomopathological correlation.

To establish if the videodensitometric analysis (VDA) of the intracoronary ultrasound images (IVUS) can predict the qualitative and quantitative composition of the atherosclerotic coronary plaques, thirty-one patients who had undergone anatomopathological study of directional coronary atherectomy (DCA) samples and pre- and post-intervention IVUS image were analyzed. The video IVUS images were digitized in a 512 x 512 matrix and analyzed for densitometric differences with an Automatic Image Analysis System (AIAS) (Vidas 2000, Zeiss Kontron). The components of the plaque were arbitrarily divided into three densitometric categories using a 256 gray scale: high density (HD) 121-255, medium (MD) 81-120 and low (LD) 30-80. The relative percentage of each component was automatically recorded. The DCA samples were microscopically examined and put into the AIAS. The components were divided into: collagenous tissue (CT); lipid-necrotic debris (LND); proliferative tissue (PT). The area of each component was expressed as a percentage of the total. Linear correlation analysis was applied. Comparison between the IVUS and the histological composition of the plaque showed that: HD corresponded to CT; MD to PT; LD to LND. The correlation between the percentage distribution of the densitometric categories and the anatomopathological components showed a correlation coefficient r = 0.91 between HD and CT; r = 0.87 between MD and PT; r = 0.88 between LD and LND. The VDA of the IVUS can distinguish three basic components of the atherosclerotic plaque: fibrous, lipid-necrotic and proliferative tissue, allowing absolute and relative quantitative analysis. This capability may be of interest for device selection and histopathological correlation.

Adult↗
PubMed1993

Quantitative analysis of enzymic digests of DNA using gel electrophoresis.

Quantitative electrophoresis of enzymic digests of DNA and its applications are reviewed. Factors affecting the overall analysis such as DNA length distribution, labels for visualizing DNA, techniques for quantitation, and electrophoresis itself are studied. Methods to analyze restriction fragments and lesions in DNA by gel electrophoresis are presented.

Animals↗
PubMed1996

Computer based quantitative analysis of capillary abnormalities in systemic sclerosis and its relation to plasma concentration of von Willebrand factor.

OBJECTIVES: To evaluate an objective and quantitative method for assessment of capillary abnormalities in systemic sclerosis (SSc). METHODS: Nailfold capillaries were investigated by capillary microscopy and photographed in 17 consecutive SSc patients (five with diffuse cutaneous systemic sclerosis (dSSc) and 12 with limited cutaneous systemic sclerosis (lSSc)) and in 17 healthy controls. Investigators having no access to clinical data made drawings from magnified projections of coded photographs and analysed them using a computer program. Capillary density (capillary loops/mm in the distal row) and median capillary loop area were calculated. Presence of functional or organic arterial changes was evaluated by measurement of finger pressure with finger cooling. Plasma concentration of von Willebrand factor (VWF) was analysed using an enzyme linked immunosorbent assay (ELISA). RESULTS: In 16 of 17 SSc patients and 13 of 17 controls the technical quality of the photographs was sufficient for computer analysis. Capillary density was decreased in dSSc (median 6.9 loops/mm) and in lSSc (median 3.8 loops/mm) compared with healthy controls (8.9 loops/mm) and median capillary loop area was increased in dSSc (7.3 x 10(-3) mm2) and in lSSc (8.5 x 10(-3) mm2) compared with healthy controls (5.0 x 10(-3) mm2). An inverse relation was found between capillary density and median capillary loop area in SSc patients. Plasma VWF was increased in patients (median 401 IE/l in dSSc and 409 IE/l in lSSc) compared with controls matched for age and sex (median 276 IE/l). Computer based analysis showed capillary density below the control range and median capillary loop area above the control range in 14 of 16 SSc patients. Measurement of finger pressure with finger cooling showed organic vascular changes in nine of 13 SSc patients. CONCLUSION: Computer based quantitative analysis has low interobserver variability and is a quantitative and sensitive method of assessing capillary abnormalities in SSc.

Adolescent↗
PubMedDate not supplied

[Analysis of gait using motography in healthy children and patients with neurologic disorders. II: Quantitative analysis].

Light pattern recording of movements by Motografie results in data representing changes in space and time; single pictures of these curves can be analysed in detail. The method was used for gait analysis in two healthy children, in a boy with minimal cerebral dysfunction and hyperactivity, and in two patients with spastic diplegia. From describing all phases of gait cycles different variables were chosen to assess movement patterns quantitatively; thus, curves could be described by various parameters. Differences were seen between normal, mildly impaired and severely handicapped children. Results obtained are in good agreement with a qualitative analysis of pictures and with data from the literature using different methods.

Adolescent↗