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PubMed1990

The effects of 5% carbon dioxide on the quantitative analysis of long-term pathology of the brain after surface hypothermia.

To evaluate the effects of 5% carbon dioxide (CO2) administration for hypothermic circulatory arrest, neurological evaluation and pathological studies were carried out on the canine brain. Twenty-two dogs were assigned to five groups: Group 1: Three dogs without hypothermia were sacrificed as the control group. Group 2: Nine dogs were subjected to surface hypothermia (20 degrees C) under deep ether anesthesia with 100% oxygen (O2) and hyperventilation. Circulatory arrest time was 30 min in Group 2A and 60 min in Group 2B. Group 3: Ten dogs were surface cooled (20 degrees C) under deep ether anesthesia with a 95% O2 and 5% CO2 mixture. Thirty minutes of circulatory arrest was instituted in Group 3A and 60 min in Group 3B. Dogs in Groups 2 and 3 were surface rewarmed and kept alive until they were sacrificed electively 6 or more months later. Results were as follows: (i) Postoperative neurological disturbance was detected in only two dogs in Group 2B. (ii) The percentage of damaged nerve cells among the total nerve cells counted in the cerebral cortex of the frontal lobe was significantly greater in Groups 2A (22.4%), 2B (30.1%), 3A (19.6%), and 3B (22.2%) compared with Group 1 (7.1%). (iii) The number of glia cells per nerve cell in the cerebellar dentate nucleus was significantly higher in Group 2B (27.2) than in Groups 1 (11.8), 2A (16.7), 3A (17.9), and 3B (18.6). (iv) The number of Purkinje cells in a 10-mm length of the cerebellum was markedly reduced to 89 in Group 2B compared with 122, 134, and 117 in Groups 1, 2A, and 3A, respectively. In conclusion, the results of quantitative pathological brain analysis reflected the incidence of postoperative neurological disturbance and suggested that the administration of 5% CO2 could prolong the time limit for circulatory arrest.

Animals↗
PubMed1986

Quantitative analysis of adenosine: statistical comparison of radioimmunoassay and gas chromatography-mass spectrometry-selected ion monitoring methods.

A new method for quantitating adenosine concentration by capillary gas chromatography-mass spectrometry-selected ion monitoring (GC-MS-SIM) has been developed and used as a reference method for evaluating a newly developed radioimmunoassay (RIA) for adenosine. Details of the GC-MS-SIM method are presented, along with the comparative results and uncertainties of both methods. General considerations in the statistical analysis of method comparison data are discussed with particular reference to studies using quantitative mass spectrometry as the standard method; the adenosine methods are used as specific examples in this discussion. Simultaneous estimation of the y-intercept and slope of the least squares regression line relating the results of the two methods using the 95% joint confidence ellipse demonstrated the absence of either constant or proportional error between the two methods. The relatively small uncertainty in the GC-MS-SIM measurements had no significant effect on the linear regression. Random error between the two methods was detected, and was estimated by the coefficient of variation in the RIA data as ten percent of the RIA value.

Adenosine↗
PubMed1997

[Quantitative analysis of soporific sedative drugs and local anesthetic drugs with unidentical standard substance by GC-AED].

According to the principle of GC-AED (gas chromatography-atomic emission detector), the possibility of quantitative determination of samples by different substances as internal standard was studied. The element C was determined at wavelength of 496 nm. The relative response factors of 17 soporific sedative and local anesthetic drugs were analyzed with an internal standard of proadifen hydrochloride under optimized analytical conditions. Oven temp.: 45 degrees C (0.5 min)-35 degrees C.min-1--120 degrees C-15 degrees C.min-1--220 degrees C-5 degrees C.min-1--250 degrees C; Cool on column injector temp: 60 degrees C-50 degrees C.min-1--250 degrees C (0.2 min); inject volume: 1 microliter; column head pressure: 145 kPa. The results show that the element C(496) in identical or unidentical substances has similar relative response factor. The RSD is 10.21%, which means that a sample can be quantitatively determined by a different substance when the analysis condition and the selected internal standard are suitable. An amobarbital sample of 109.0 micrograms.ml-1 was quantitatively determined by using methylphenobarbitone, pramoxine, lidocaine and itself as internal standard. The results are 117.6, 115.6, 110.0 and 102.14 micrograms.ml-1, respectively. They can be quantitatively determined by each other.

Anesthetics, Local↗
PubMed1989

Considerations in the quantitative analysis of autoradiograms from 2-dimensional gels.

Two-dimensional (2-D) gel electrophoresis has been used in conjunction with autoradiography and computerized optical densitometry for quantitating specific protein synthesis. However, accurate quantitation of 2-D autoradiograms requires the prior assessment of such parameters as linearity, reciprocity, and reproducibility. The present study was performed to determine the contribution of each of these to the dissimilation of beta-emission and autoradiographic density, and of density and protein synthesis. Various aliquot volumes of a single complex protein specimen labeled with 35S-amino acids were subjected to 2-D gel electrophoresis, and these gels were serially exposed at graded intervals. The peak densities and volumes of the 111 visualized spots were used to examine the above parameters. In our computerized scanning system, the peak density is a more accurate and reproducible parameter of optical density than is spot volume. Approximately 30% of the dynamic range of peak density is non-linear; quantitation of spots above or below the linear range leads to inaccuracies in quantitation. In addition, the phenomenon of reciprocity, which states that density is directly proportional to exposure (beta-emission of 35S x time), is shown to fail as aliquot volume, or mass of 35S increases. The implications of reciprocity failure to accurate quantitation are discussed. Finally, the sources of variance in autoradiographic analysis were examined, by assessing the intra-scan, intra-gel run, and inter-gel run coefficients of variation. The results of this study show that autoradiographic densitometry is an effective method for quantitation of 2-D gels, but linearity, reciprocity, and reproducibility must be assessed prior to its experimental use. Restrictions of such use are suggested.

Animals↗
PubMed1982

Quantitative analysis for delta 9-THC, 11-hydroxy-delta 9-THC, and 9-carboxy-delta 9-THC in plasma using GC/CI-MS.

A method for quantitative measurement of delta 9-THC concentrations in plasma has been developed and applied to the analysis of more than 2000 samples over the past 4 years. The method includes addition of deuterium-labeled delta 9-THC to the plasma for use as the internal standard, a simple and relatively rapid solvent extraction procedure, formation of the trimethylsilyl derivative, and quantitation by selected ion monitoring using ammonia chemical ionization. A similar procedure has also been developed for simultaneous analysis of delta 9-THC and two of its major metabolites in plasma. The latter procedure requires use of a glass capillary column for assays of plasma samples in which the delta 9-THC concentration is below 10 ng/ml. Sensitivities for both methods permit quantitation of THC and its metabolites at concentrations as low as 0.2 ng in 1-ml plasma samples.

Dronabinol↗
PubMed1998

Quantitative analysis of HLA DR expression and lymphocytic infiltrate in laryngeal cancer including clinical and morphological correlations.

HLA DR antigen expression in tumor cells and lymphocytic infiltrates at the tumour periphery were investigated in 68 laryngeal carcinomas. The tissue sections were studied by a quantitative method using computer image analysis system. The highest number of CD45RO+ cells was observed in the groups of the lowest clinical stage. There were statistically significant differences between the groups in the number of T cells, whereas no differences were found in HLA DR+ cancer cell number, B cell number or mitosis count. Statistical analysis revealed a significant correlation between T-cell number at the periphery of the tumour and the number of cancer cells showing HLA DR expression. The results of the analysis, using Cox proportional hazard model with selected factors, showed that only HLA DR expression in cancer cells had a significant effect on survival, whereas the number of CD45RO+ and CD20+ cells, histological grade and mitosis count did not contribute further to prognostic information. To our knowledge, this is the first time that HLA DR expression and its correlation with lymphocytic infiltration have been shown by a quantitative method in laryngeal cancer.

Carcinoma, Squamous Cell↗
PubMed1992

The objective evaluation of alternative treatment plans. III: The quantitative analysis of dose volume histograms.

The computer program OSCAR evaluates dose-volume histograms in a consistent way for use in 3-dimensional treatment planning. Based on a dose prescription specified by a radiation oncologist, the technique provides a quantitative and easily understood visual analysis of a proposed dose distribution. Rapid, reliable, and consistent choices can be made between alternative treatment plans, and if necessary the results of OSCAR calculations can be used to guide the design of a plan that will be closer to the required prescription. The method is well suited to use in the definition of treatment protocols. The use of OSCAR is demonstrated by applying it to the evaluation of alternative volumetric treatment plans for ca lung. The results demonstrate the importance of using corrections for inhomogeneous tissue density in the calculation of 3-dimensional dose distributions.

Computer Graphics↗
PubMed2004

Model building and quantitative analysis of a tandem immuno-capturing assay as a screening tool for breast cancer.

The onset of breast cancer appears to occur, on average, a decade earlier in Mexican women in comparison to American or European women. Early detection and prevention of breast cancer are of crucial importance to increase survival and improve quality of life. Based on the molecular elucidation of critical events leading to breast carcinogenesis, a tandem immuno-capturing blood test was developed as a quantitative population screening assay in view of providing a cost-effective and non-invasive alternative to population screening. Clinical analysis of 63 Mexican women within an age group of 35-70, revealed that Interstron activity increases from 800+/-65 IUJPA (Interstron Units) in the asymptomatic normal women to 994+/-100 IUJPA in the symptomatic/benign group, reaching 1289+/-81 IUJPA in the cancerous group. Accordingly, activity thresholds were established at 800 and 1200 IUJPA respectively, encompassing three risk groups: (i) Healthy Otherwise Normal (<800 IUJPA); (ii) Grey Risk Area (>800 and <1200 IUJPA), and (iii) At Risk group (>1200 IUJPA). Taking into account both baseline and clinical case reports, the Healthy Otherwise Normal group and the At Risk group were mostly homogeneous in nature, comprising a population of normal and cancer patients respectively. The Grey Risk group is heterogeneous, likely reflecting a transitional nature towards a potential early stage of breast disease development. Based on these results, a screening algorithm was developed as the underlining principle for population surveillance encompassing over 30,000 Mexican women. The current screening results have enabled us to objectively prioritize medical attention to approximately 1 in 8 women out of the general population mapped within the At Risk group. Overall, our findings suggest that monitoring Interstron activity units provides a valuable quantitative screening analysis as to selectively streamline the population of women in need of early medical counseling and/or mammography, thereby enhancing both the quality and cost-effectiveness of preventative population surveillance programs targeting breast cancer.

Adult↗
PubMed2006

Automated quantitative analysis of DCC tumor suppressor protein in ovarian cancer tissue microarray shows association with beta-catenin levels and outcome in patients with epithelial ovarian cancer.

BACKGROUND: The deleted in colorectal cancer (DCC) protein, the product of DCC tumor suppressor gene, is frequently altered in cancer. Preclinical data demonstrate that DCC regulates beta-catenin levels. Here, we sought to determine the association of DCC with beta-catenin protein levels, clinicopathological parameters and patient outcome in ovarian cancer using a method of in situ compartmentalized protein analysis. METHODS: A tissue array composed of 150 advanced-stage ovarian cancers, treated with surgical debulking and platinum-paclitaxel (Taxol) combination chemotherapy, was constructed. For evaluation of protein expression, we used an immunofluorescence-based method of automated in situ quantitative measurement of protein analysis (AQUA). RESULTS: One hundred and twelve patients (74%) had sufficient tissue for AQUA. The median follow-up time for the entire cohort was 33 months. Patients with low nuclear DCC expression had a 3-year progression-free survival (PFS) rate of 0% compared with 33% of those with high DCC expression (P = 0.0067). In multivariate analysis, low nuclear DCC expression level retained its prognostic significance for PFS. Between DCC and beta-catenin, a significant relationship was found, where tumors with low DCC had low beta-catenin and vice versa (P = 0.003). CONCLUSIONS: Low nuclear DCC levels predict for poor patient outcome in epithelial ovarian cancer. DCC may exert its antitumor function, in part, through regulation of beta-catenin levels.

Automation↗
PubMed1987

A quantitative analysis of sniffing strategies in rats performing odor detection tasks.

The sniffing strategies of rats performing two learned odor detection tasks were monitored with a pneumotachograph and quantitatively analyzed with respect to fifty-two characteristics. The results of this study demonstrated that the rat's sniffing varied for different odorants, different concentrations of the same odorant, and between air and odor trials. The variations resulted from changes in such descriptors as volume, duration, average flow rate, peak flow rate and sniff number. In general, a sniffing pattern began with one or two inspirations followed by alternating inspirations and expirations. Comparison of earlier and later sniffs in a bout demonstrated a growth towards both a maximum inspiratory and expiratory sniff which had the largest duration, volume, average flow rate and peak flow rate. These maximum sniffs occurred at or near the end of a bout. Although analysis of the fifty-two characteristics was quantitatively useful in determining the physiologic values and airflow patterns generated by sniffing, a single univariate response measure incorporating twelve characteristics was the best descriptor of how sniffing patterns varied with odorant stimuli.

Animals↗
PubMed2002

Gas chromatography/negative-ion chemical ionisation mass spectrometry for the quantitative analysis of morphine in human plasma using pentafluorobenzyl carbonate derivatives.

A sensitive and specific method for the quantitative determination of morphine in human plasma is presented. Morphine was extracted from plasma by solid phase extraction on C18 and converted to its pentafluorobenzyl carbonate trimethylsilyl derivative. The derivatives were analysed without further purification. Using gas chromatography/negative ion chemical ionisation mass spectrometry, a useful diagnostic fragment ion at m/z 356 is obtained at high relative abundance. Deuterated morphine was used as internal standard. Calibration graphs were linear within the range 1.25 to 320 nmol/L. Intra-day precision was 3.82% (15 nmol/L), 2.85% (75 nmol/L) and 4.13% (225 nmol/L), inter-day variability was found to be 1.77% (15 nmol/L), 4.95% (75 nmol/L) and 9.88% (225 nmol/L). Inter-day accuracy showed deviations of 2.18% (15 nmol/L), -0.72% (75 nmol/L) and -0.13% (225 nmol/L). The method is rugged and robust and has been applied to the batch analysis of morphine during pharmacokinetic profiling of the drug.

Calibration↗
PubMed2001

Quantitative analysis of regional motion and thickening by gated myocardial perfusion SPECT: normal heterogeneity and criteria for abnormality.

UNLABELLED: Quantitation of regional myocardial function is valuable in patients with coronary artery disease. This study assessed normal heterogeneity and developed and validated normal limits for quantitative regional motion and thickening by gated myocardial perfusion SPECT. METHODS: Patients underwent rest (201)Tl/exercise (99m)Tc-sestamibi gated SPECT. Reference values of motion and thickening for 20 myocardial segments were obtained in 105 patients with <5% likelihood of coronary disease (low-likelihood group). Criteria for abnormality of motion and thickening were defined for each segment, using receiver operator characteristic analysis, in 101 patients with coronary disease (training group). Semiquantitative visual interpretation was used as the gold standard. These criteria were prospectively validated in 100 patients (validation group). Criteria for grading motion and thickening abnormalities by severity levels were also defined and validated. RESULTS: Normal thickening decreased substantially along the longitudinal axis of the left ventricle, from 69% +/- 13% at the apex to 25% +/- 11% at the basal segments, whereas normal motion varied within the same ventricular plane. Validation of the criteria for abnormality yielded high accuracy in the detection of motion abnormalities (sensitivity, 88%; specificity, 92%) and thickening abnormalities (sensitivity, 87%; specificity, 89%). Quantitative motion and thickening segmental scores showed good agreement with visual scores. CONCLUSION: Normal regional myocardial contraction by gated myocardial perfusion SPECT is characterized by a substantial apex-to-base decline in thickening and by circumferential heterogeneity in endocardial motion. The assignment of segment-specific threshold values for defining motion and thickening abnormalities provided reasonably accurate identification and grading of regional myocardial dysfunction.

Aged↗
PubMed2005

Quantitative analysis of multiple illicit drugs in preserved oral fluid by solid-phase extraction and liquid chromatography-tandem mass spectrometry.

We present a validated method for the simultaneous analysis of basic drugs which comprises a sample clean-up step, using mixed-mode solid-phase extraction (SPE), followed by LC-MS/MS analysis. Deuterated analogues for all of the analytes of interest were used for quantitation. The applied HPLC gradient ensured the elution of all the drugs examined within 14 min and produced chromatographic peaks of acceptable symmetry. Selectivity of the method was achieved by a combination of retention time, and two precursor-product ion transitions for the non-deuterated analogues. Oral fluid was collected with the Intercept, a FDA approved sampling device that is used on a large scale in the US for workplace drug testing. However, this collection system contains some ingredients (stabilizers and preservatives) that can cause substantial interferences, e.g. ion suppression or enhancement during LC-MS/MS analysis, in the absence of suitable sample pre-treatment. The use of the SPE was demonstrated to be highly effective and led to significant decreases in the interferences. Extraction was found to be both reproducible and efficient with recoveries >76% for all of the analytes. Furthermore, the processed samples were demonstrated to be stable for 48 h, except for cocaine and benzoylecgonine, where a slight negative trend was observed, but did not compromise the quantitation. In all cases the method was linear over the range investigated (2-200 microg/L) with an excellent intra-assay and inter-assay precision (coefficients of variation <10% in most cases) for QC samples spiked at a concentration of 4, 12 and 100 microg/L. Limits of quantitation were estimated to be at 2 microg/L with limits of detection ranging from 0.2 to 0.5 microg/L, which meets the requirements of SAMHSA for oral fluid testing in the workplace. The method was subsequently applied to the analysis of Intercept samples collected at the roadside by the police, and to determine MDMA and MDA levels in oral fluid samples from a controlled study.

Chromatography, Liquid↗
PubMed1974

Quantitative analysis of cholesterol in 5 to 20 microliter of plasma.

A gas-liquid chromatographic micromethod for quantitation of cholesterol in 20 micro l of plasma was developed using 5alpha-cholestane as an internal standard, saponification with tetramethylammonium hydroxide-isopropanol, and extraction with tetrachloroethylene-methyl butyrate. Cholesterol levels in plasma samples were calculated by comparing cholesterol-cholestane peak height ratios with those of preassayed reference plasma. Over a plasma cholesterol range of 44 to 468 mg/100 ml, the gas-liquid chromatographic micromethod and the automated ferric chloride colorimetric method gave nearly identical results (r = 0.99) in duplicate aliquots of 131 plasma samples.

Adult↗
PubMedDate not supplied

Quantitative analysis of benzene by selected ion monitoring/gas chromatography/mass spectrometry.

A selected ion monitoring gas chromatographic/mass spectrometric method for the quantitative determination of benzene in air, breath, and blood was developed utilizing a headspace assay with benzene-d3 as an internal standard. Limits of detection for 2 ng/mL in blood and 0.1 ppb in a 5-L sample of air or breath were attained. The influence of contamination by background benzene on the analytical process was studied carefully. For cases where background contamination could not be adequately controlled, the assay was modified for the quantitative determination of labelled benzenes six mass units heavier than natural benzene (benzene-d6 or benzene-13C6). Use of the method for the analysis of natural benzene was illustrated for the measurement of background levels in urban smokers and nonsmokers.

Air↗
PubMed1986

Quantitative analysis of myocardial fibrosis in normals, hypertensive hearts, and hypertrophic cardiomyopathy.

The distribution of fibrosis was studied quantitatively in the entire left ventricular wall of a transverse slice of the heart from 10 necropsy cases of hypertrophic cardiomyopathy, 10 cases of hypertensive heart disease, and 20 normal adults. The percentage area (mean (SD)) of fibrosis in the left ventricular wall in hypertrophic cardiomyopathy (10.5 (4.3)%) was significantly greater than that in hypertensive heart disease (2.6 (1.5)%) or in normal hearts (1.1 (0.5)%). In hypertrophic cardiomyopathy the percentage area of fibrosis was greater (13.1 (4.8)%) in the ventricular septum than in the left ventricular free wall (7.7 (4.2)%) whereas in hypertensive heart disease and normal hearts values in these two areas were similar. The percentage area of fibrosis in the left ventricular free wall (where myocardial fibre disarray was not extensive even in hypertrophic cardiomyopathy) was greater in hypertrophic cardiomyopathy than in hypertensive heart disease. The percentage area of fibrosis correlated with heart weight in hypertensive heart disease, but not in hypertrophic cardiomyopathy. These results suggest that widespread fibrosis in hypertrophic cardiomyopathy cannot be explained by cardiac hypertrophy alone, and that disarray and other factors are also important in pathogenesis. The increase in the percentage area of fibrosis from the outer to the inner third of the left ventricular free wall in hypertrophic cardiomyopathy and in hypertension probably reflected transmural gradients of wall stress and myocardial fibre diameter. Although fibrosis is not specific to hypertrophic cardiomyopathy, its quantification and analysis of its regional distribution provide information that is useful in investigating the pathophysiology of the disorder.

Adolescent↗
PubMed2005

Quantitative analysis of tumor mitochondrial RNA using microarray.

AIM: To design a novel method to rapidly detect the quantitative alteration of mtRNA in patients with tumors. METHODS: Oligo 6.22 and Primer Premier 5.0 bio-soft were used to design 15 pairs of primers of mtRNA cDNA probes in light of the functional and structural property of mtDNA, and then RT-PCR amplification was used to produce 15 probes of mtRNA from one normal gastric mucosal tissue. Total RNA extracted from 9 gastric cancers and corresponding normal gastric mucosal tissues was reverse transcribed into cDNA labeled with fluorescein. The spotted mtDNA microarrays were made and hybridized. Finally, the microarrays were scanned with a GeneTAC laser scanner to get the hybridized results. Northern blot was used to confirm the microarray results. RESULTS: The hybridized spots were distinct with clear and consistent backgrounds. After data was standardized according to the housekeeping genes, the results showed that the expression levels of some mitochondrial genes in gastric carcinoma were different from those in the corresponding non-cancerous regions. CONCLUSION: The mtDNA expression microarray can rapidly, massively and exactly detect the quantity of mtRNA in tissues and cells. In addition, the whole expressive information of mtRNA from a tumor patient on just one slide can be obtained using this method, providing an effective method to investigate the relationship between mtDNA expression and tumorigenesis.

Blotting, Northern↗
PubMed1997

Quantitative analysis of trabecular morphogenesis in the human costochondral junction during the postnatal period in normal subjects.

BACKGROUND: Quantitative histomorphometric features of the bone growth plate in the human rib have been investigated in infants, ranging in age from 3-36 weeks (mean 18.6 weeks) to provide data currently not available. METHODS: Measurements were taken in each histological zone of the growth plate. Data from 20 cases were pooled and parameters describing the characteristic features of trabecular bone calculated using morphometric formulae. The measurements were made from the resting zone of the cartilage to the secondary spongiosa, 3.78 mm from the starting point. RESULTS: Cartilage volume fraction decreased from 78% in the resting zone to a bone volume fraction of between 20% and 30% in the secondary cancellous bone. Cartilage matrix surface increased rapidly in the cartilage and bone mineral surface declined in correspondence with the development of primary bone. The distance between chondrocyte lacunae was observed to decrease throughout the cartilage to a transverse septa thickness of 18 microns in the hypertrophic zone. A rapid increase in trabecular thickness to 128 microns was observed in the primary spongiosa, the secondary spongiosa ranging between 137 microns and 168 microns. Spacing, chondrocyte profile transverse diameter, increased to 30 microns in the hypertrophic zone, following which an increase in trabecular separation to 347 microns was observed in the primary spongiosa. The number of transverse intervals between individual chondrocyte lacunae was observed to increase in the cartilage to a maximum of 21.3 cartilaginous or mineralised septa per mm of growth plate length in the hypertrophic zone. Trabeculae in the metaphysis then decreased in number to approximately 1.5 trabeculae per mm in the secondary spongiosa. CONCLUSIONS: These data thus provide new insight into the development of trabecular structure during growth and normal values for the comparison of tissue from skeletal dysplasias and growth disorders.

Achondroplasia↗