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PubMed2002

Quantitative analysis of lung perfusion in patients with primary pulmonary hypertension.

UNLABELLED: The aim of this study was to evaluate quantitatively the heterogeneity of lung perfusion scans in patients with primary pulmonary hypertension (PPH) and to compare it with the severity of disease. METHODS: Lung perfusion scans were obtained on 22 patients with PPH and 12 age-matched control subjects. The perfused area rates (PARs) were calculated by dividing the lung area in each 10% threshold width from 10% to 100% of maximal counts by total lung area. The total absolute difference in the PAR between each patient and the mean control value was assumed as the perfusion index of the lung (P index). The P index was compared with hemodynamic parameters and the right ventricular ejection fraction (RVEF), including 7 patients who received long-term vasodilator therapy. RESULTS: The P index correlated significantly with mean pulmonary arterial pressure (P < 0.001) and RVEF (P < 0.05). In patients with vasodilator therapy, the P index was improved significantly after therapy (P < 0.05) and was associated with a reduction in pulmonary arterial pressure. CONCLUSION: Quantitative assessment of lung perfusion irregularity might provide useful information about the severity of disease and the effect of therapy in addition to the routine visual representation.

Adult↗
PubMed2003

Quantitative analysis for assessing regional function of liver by using 99mTc-GSA SPECT.

In the present study, we developed quantitative index for evaluating regional liver function using 99mTc diethylenetriamine-pentaacetic acid galactosyl human serum albumin (GSA). A three head SPECT equipped with a low energy high resolution parallel hole collimator was used. Used pre-filter was Butterworth and axial images were reconstructed by a ramp filter without attenuation correction. Correlation between SPECT counts and net concentration of activity of radioisotopes was evaluated in basic consideration using LKS and Nine-Ball phantoms. SPECT Counts = 0.6 x RI concentration. There was a simple correlation among GSA receptor amounts (Cr), injected GSA amounts (S), free GSA amounts (Cf), and intra hepatic receptor ratio ((Cr ratio)). Cr = S - Cf. (Cr ratio) = Cr/S, 0 < (Cr ratio) < 1. Injected GSA amounts can be calculated from injected net RI counts. Free GSA amounts can be evaluated from counts of the heart. GSA receptor amounts can be assumed by performing SPECT three times in series. Regional GSA receptor amounts can be evaluated from the ratio between the region's counts and whole counts. In clinical SPECT images, we could evaluate the regional GSA receptor amounts before and after chemolipiodolization. In conclusion, our method is a simple quantitative index of analyzing regional GSA receptor amounts.

Humans↗
PubMedDate not supplied

[Gas chromatography in quantitative analysis of hydrocyanic acid and its salts in cadaveric blood].

A direct gas chromatography method was designed for the quantitative determination of cyanides (prussic acid) in cadaveric blood. Its sensitivity is 0.05 mg/ml. The routine volatile products, including substances, which emerge due to putrefaction of organic matters, do not affect the accuracy and reproducibility of the method; the exception is H-propanol that was used as the internal standard. The method was used in legal chemical expertise related with acute cyanide poisoning (suicide) as well as with poisoning of products of combustion of nonmetals (foam-rubber). The absolute error does not exceed 10% with a mean quadratic deviation of 0.0029-0.0033 mg.

Cadaver↗
PubMed1982

[Quantitative analysis of the mitochondrial ultrastructure of cardiomyocytes in rats adapting to altitude hypoxia].

A study was made of the quantitative characteristics of mitochondria of the myofibrillar, perinuclear and subsarcolemmal zones of cardiomyocytes during long-term adaptation of rats to an "altitude" of 9000 m in a pressure chamber. The data are presented on the role played by hypertrophic and hyperplastic processes occurring in the mitochondrial apparatus in supporting viability of cardiac cells at high altitude.

Adaptation, Physiological↗
PubMed1981

Radionuclide ejection fraction: a technique for quantitative analysis of motor function of the human gallbladder.

A new noninvasive technique for the measurement of the gallbladder evacuation quantitatively is described. By using a radioactive bile marker [99mTc]HIDA, the evacuation of the gallbladder is measured nongeometrically in terms of ejection fraction (fractional bile volume emptied from the gallbladder) and ejection rate (dv/dt). The counts and volume in an in vitro gallbladder phantom under pinhole collimator geometry show a linear relationship (r = 0.998) enabling the replacement of gallbladder bile volume by bile counts before and after evacuation. The counts ejection-fraction shows a high degree of correlation (r = 0.998) with the measured-volume method. The movement of the gallbladder during respiration does not effect the measurement of ejection fraction. The technique allows simultaneous imaging and quantitation, and it is highly reproducible, carrying an interobserver and reproducibility mean error of 5%. This technique is suitable for studying the motor functions of the gallbladder and the effects of various pharmacologic agents on its evacuation. The clinical usefulness of the technique requires further testing.

Adult↗
PubMed1994

[CSF dynamics in the patients with syringomyelia associated with Chiari's malformation--quantitative analysis on cine MRI].

In a series of 12 patients with syringomyelia associated with Chiari's malformation, the authors quantitatively analyzed cerebrospinal fluid (CSF) dynamics in the subarachnoid space of the craniospinal junction, using cine MRI combined with pre-saturation method. In most of subjects, cine MRI revealed (1) decreased or increased maximum velocity of CSF in the caudal direction and (2) disturbed CSF motion in the caudal direction (delayed % cardiac cycle) in the craniospinal junction, strongly suggesting disturbed CSF dynamics in the craniospinal junction because of the tonsilar herniation. Of 12 subjects, 8 patients underwent foramen magnum decompression and 4 underwent syringo-subarachnoid shunt (SS shunt). In the patients who showed marked collapse of syrinx after foramen magnum decompression, follow-up cine MRI revealed the normalization of % cardiac cycle, representing postoperative improvement of CSF dynamics in the craniospinal junction. On the other hand, % cardiac cycle did not improve significantly in the patients who did not show marked collapse of the syrinx or suffered from meningitis after surgery. Significant changes were not observed in the patients who underwent SS shunt. In summary, these results suggested that cine MRI combined with pre-saturation method could detect the pathophysiological changes and evaluate the efficacy of the surgery, especially foramen magnum decompression, in the patients with syringomyelia associated with Chiari's malformation.

Adolescent↗
PubMed2004

Quantitative analysis of fungal DNA in chronic rhinosinusitis.

OBJECTIVES/HYPOTHESIS: Fungi have been recognized as important pathogens in sinusitis; however, they are equally present in patients with and without sinusitis. The authors postulated that the quantity of fungal DNA in the nose is determinant of disease, is greater in patients with chronic rhinosinusitis, and is directly correlated to their quality of life. STUDY DESIGN: Prospective recruitment of patients with chronic rhinosinusitis. METHODS: Objective quality of life data were collected using three validated questionnaires: the Sinonasal Outcomes Test (SNOT-20), Medical Outcomes Short-Form 36 Survey (SF-36), and Guy Marks Asthma Questionnaire (GMAQ). Endoscopically guided middle meatus mucosal samples were collected from patients with chronic rhinosinusitis and normal control subjects. Fungal-specific polymerase chain reaction was performed on each sample. Every fungal-positive sample underwent fungal-specific quantitative polymerase chain reaction analysis. Statistical analysis was used to correlate fungal DNA quantities with outcomes indices between groups. RESULTS: Patients with chronic rhinosinusitis had a mean SNOT-20 index of 32.0 as compared with a SNOT-20 index of 17.3 (P <.01) in the normal control subjects. There were no statistical differences between the groups' indices for the SF-36 or GMAQ outcomes questionnaires. Four of 19 (21.1%) patients with chronic rhinosinusitis and 7 of 19 (36.8%) normal control subjects had positive findings for fungal DNA using polymerase chain reaction. The median relative quantity of fungal DNA to human DNA for chronic rhinosinusitis and control samples was identical (0.13) using quantitative polymerase chain reaction. CONCLUSION: The quantity of fungal DNA in the middle meatus did not differ in patients with and without chronic rhinosinusitis and was not correlated with quality of life outcomes. Therefore, the quantity of fungi does not explain pathogenicity in patients with chronic rhinosinusitis. However, because of small sample size, the study must be replicated in a larger patient population.

Chronic Disease↗
PubMed2006

Quantitative analysis of anti-hepatitis C virus antibody-secreting B cells in patients with chronic hepatitis C.

To investigate the quantitative characteristics of humoral immunity in patients with hepatitis C, we established an enzyme-linked immunosorbent spot (ELISpot) assay for detection of anti-hepatitis C virus (HCV)-secreting B cells. Receiver operating characteristic curve analysis demonstrated 100% specificity and 58% to 92% sensitivity for detecting B-cell responses to NS5b, NS3, E2, and core antigens. The median sum of anti-HCV-secreting B cells to all HCV antigens tested was significantly higher in 39 patients with chronic hepatitis C (47.3 spot forming cells [SFCs]/10(6) peripheral blood mononuclear cells [PBMCs]) than in 9 recovered subjects (15.3 SFCs/10(6) PBMCs; P = .05) or 11 uninfected controls (5.3 SFCs/10(6) PBMCs; P < .001); the significant difference (P = .018) in chronic versus recovered patients was in reactivity to nonstructural antigens NS3 and NS5b. Anti-HCV immunoglubulin M (IgM)-secreting B cells were also readily detected and persisted decades into HCV infection; there was no difference in IgM-positive cells between chronic and recovered patients. ELISpot reactivity to genotype 1-derived antigens was equivalent in patients of genotypes 1, 2, and 3. There was significant correlation between the numbers of anti-HCV IgG-secreting B cells and serum aminotransferase and to the level of circulating antibody. In conclusion, ELISpot assays can be adapted to study B-cell as well as T-cell responses to HCV. Measurement at the single-cell level suggests that humoral immunity plays a minor role in recovery from HCV infection and that B-cell immunity is strongest in those with persistent infection.

Adult↗
PubMed1977

Quantitative analysis of tubulin and microtubule compartments in isolated rat hepatocytes.

A combined morphometric and biochemical approach has been used to identify and quantitate microtubules and tubulin in isolated hepatocytes. The total soluble pool of microtubule protein was estimated by specific high affinity binding to radiolabeled colchicine. Scatchard analysis of the data identified two populations of binding sites: high affinity-low capacity sites resembling tubulin and low affinity-high capacity sites believed to represent nonspecific colchicine-binding sites. Data from these studies indicate that tubulin represents 1% of the soluble protein of the cell, that 9.0 X 10(-14) dimers of tubulin are present per microgram soluble hepatocyte protein, and that the average hepatocyte contains 3.1 X 10(7) tubulin dimers. Our calculations suggest that this amount of tubulin would form a microtubule 1.9 cm in length if totally assembled. However, stereological measurements indicate that the actual length of microtubules in the cytosolic compartment of the average hepatocyte is only 0.28 cm. Thus, these experiments suggest that only 15% of the available tubulin in hepatocytes of postabsorptive rats is assembled in the form of microtubules.

Animals↗
PubMed2000

Molecular prognostication of nasopharyngeal carcinoma by quantitative analysis of circulating Epstein-Barr virus DNA.

We investigated the prognostic implication of pretreatment plasma/serum EBV DNA concentration, as measured by real-time quantitative PCR, in nasopharyngeal carcinoma (NPC). In 91 prospectively recruited NPC patients, those with recurrence or metastasis within the first year after treatment had a higher median plasma EBV DNA concentration than those without events (41,756 copies/ml versus 5,807 copies/ml; P < 0.001, Mann-Whitney rank-sum test). In multivariate logistic regression analysis, plasma EBV DNA was an independent prognostic indicator for early clinical events [relative risk = 3.8 (95% confidence interval, 1.6-9.2 for each 10-fold increase in plasma EBV DNA concentration; P = 0.003)]. In a second cohort of 139 NPC patients followed-up for a median period of 2,027 days (interquartile range, 597-2,335 days), serum EBV DNA was found to be a significant variable associated with NPC-related death in multivariate Cox's regression analysis [relative risk = 1.6 (95% confidence interval, 1.1-2.1 for each 10-fold increase in serum EBV DNA concentration; P = 0.007)]. The quantitation of circulating EBV DNA may thus allow improved prognostication of NPC.

Adult↗
PubMed2004

Comparison of clinical and molecular surveillance in patients with advanced nasopharyngeal carcinoma after primary therapy: the potential role of quantitative analysis of circulating Epstein-Barr virus DNA.

BACKGROUND: The importance of detecting recurrence at an early stage in patients with malignant disease is well recognized. Circulating Epstein-Barr virus (EBV) DNA can be detected in patients with nasopharyngeal carcinoma (NPC). The objective of the current study was to assess the effectiveness of plasma EBV DNA monitoring in the early detection of NPC recurrence compared with conventional methods. METHODS: Patients with NPC in two prospective clinical trials who had locoregional recurrences or distant metastases were recruited into the study. Clinical data on these patients were scrutinized for evidence of recurrence. EBV DNA copy numbers in the prospectively collected plasma samples were assayed retrospectively with real-time quantitative polymerase chain reaction analysis. RESULTS: At the time of clinical recurrence, 65% of 26 patients with locoregional recurrences and all but 1 of 28 patients with distant failure had circulating EBV DNA. The difference between the time from completion of treatment to positivity for circulating EBV DNA and the time from completion of treatment to the first observed clinical abnormality was not statistically significant for patients with local recurrence (P=0.84). However, the time to the first detection of circulating EBV DNA was significantly shorter among patients with distant metastases (P<0.0001). The Kaplan-Meier estimated median time to the emergence of plasma EBV DNA was 190 days, with a 95% confidence interval (CI) of 95-300 days, and the median time to the first observed clinical abnormality was 295 days (95% CI, 276-361 days). CONCLUSIONS: Monitoring plasma EBV DNA levels surpassed traditional methods for the early detection of distant failure in patients with NPC. The role of this technique should be evaluated in prospective studies that incorporate complementary advanced imaging technology.

DNA, Viral↗
PubMed2006

Quantitative analysis of the GAL4/UAS system in Drosophila oogenesis.

The GAL4/UAS system is extensively used for targeted gene expression in Drosophila, but the strength of the GAL4 drivers and their effects on target genes are rarely quantified. Quantitative information about the strength of the perturbations introduced by the GAL4/UAS system would further expand the usefulness of the GAL4/UAS system in studying gene functions and developmental processes. We have developed an assay to determine the relative level of expression for target genes tagged with green fluorescent protein (GFP). Our assay enables the relative quantitation of fluorescent proteins within specific cell types and developmental time windows in living eggs/embryos, and permits the analysis of samples from a broad expression range. We illustrate the assay using a panel of four GAL4 drivers and three UAS responder lines in Drosophila oogenesis, discuss the issues associated with the interpretation of the quantitative data, and correlate our results with the analysis of the GAL4/UAS system at the transcript level. The imaging-based strategy described here can be used to quantify other GAL4 drivers in Drosophila and other organisms.

Animals↗
PubMed1993

Quantitative analysis of the expression and regulation of an activation-regulated phosphoprotein (oncoprotein 18) in normal and neoplastic cells.

Activation of protein kinase C results in phosphorylation of a 19-kDa protein termed 19K. Isolation and sequence analysis of a cDNA encoding the 19K protein revealed that this protein has been studied in other systems under different names. The name oncoprotein 18 (Op18) has been proposed on the basis of a postulated up-regulation in neoplastic cells. In the present report we adopt the designation Op18 for the 19K protein, and quantify this phosphoprotein in a series of leukemia/lymphoma cell lines, a panel of non-transformed cells and some terminally differentiated cell types. For this purpose we have developed reagents allowing quantitative Western-blot analysis, and quantification of Op18 on the single cell level by flow cytometric analysis. The data demonstrates a pronounced up-regulation of the Op18 protein in most leukemia/lymphoma cell lines. The HPB-ALL cell line provided the most extreme case and expressed 7 x 10(6) Op18 molecules/cell, which compares with 0.65 x 10(6) Op18 molecules/cell in non-transformed lymphoblastoid cells. The expression of Op18 appears to be restricted to cell types with proliferative potential, but it is clear from our results that up-regulation of Op18 is uncoupled from cellular proliferation. Moreover, by employing an Epstein-Barr virus based shuttle vector, we expressed Op18 cDNA in lymphoblastoid cells. This resulted in a three to fourfold up-regulation of Op18 that did not have any detectable consequences for cell-surface phenotype or cell size. However, increased expression of Op18 resulted in a partial inhibition of cell proliferation. Taken altogether, the results suggest that up-regulation Op18 levels in leukemia/lymphoma cells are strongly associated with, but not a direct cause of tumour progression.

Blotting, Western↗
PubMed1992

Cranial growth in the squirrel monkey (Saimiri sciureus): a quantitative analysis using three dimensional coordinate data.

Improvements in data gathering technology have made it possible to quickly and accurately digitize large numbers of objects. The three dimensional coordinates of 44 homologous landmarks were obtained from a sample of 104 squirrel monkey (Saimiri sciureus) crania. After sorting by sex, the crania were assigned to one of four dental age groups. Two quantitative methods, Euclidean distance matrix analysis (EDMA) and finite element scaling analysis (FESA), were used to study craniofacial form change during growth within each sex. Form differences between the sexes at each developmental age were also examined. Both sexes show a small amount of cranial growth overall; however, there are areas of substantial local growth. These areas include the anterior neurocranium and basicranium, the basioccipital, and the anterior palate. Sexual dimorphism in the craniofacial complex is minimal. The most dimorphic regions are the orbitonasal portion of the lower face, the cranial base, and the palate.

Animals↗
PubMed2002

Comparative study of fast MR imaging: quantitative analysis on image quality and efficiency among various time frames and contrast behaviors.

The purpose of this study is to quantitatively compare the image quality and efficiency provided by widely available fast MR imaging pulse sequences. A composite phantom with various T1 and T2 values and subjected to periodic motion was imaged at 1.5 T. The fast MRI sequences evaluated included fast spin-echo (FSE), single shot fast spin-echo (SSFSE), echo-planar imaging (EPI), multi-slice gradient recalled (MPGR), fast MPGR (FMPGR), and fast multi-slice spoiled gradient echo (FMPSPGR). T1-weighted (T1WI), T2-weighted (T2WI), proton-density-weighted (PDWI), and T2*-weighted (T2*WI) images were evaluated in breath-hold and non-breath-hold time frames. Analysis included measurement of image signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), nonuniformity, ghosting ratio, SNR per unit time and CNR per unit time. Among fast T2WI sequences, FSE with breath-hold time frame resulted in the highest image quality and in superior SNR and CNR efficiency by a factor of 5 or 6 as compared with conventional spin echo sequence. Among fast T1WI sequences, FMPGR and FMPSPGR both with non-breath-hold time frame produced the highest image quality and SNR and CNR efficiency by a factor of greater than 5 as compared with conventional spin echo. Among fast PDWI and T2*WI sequences, FSE produced the highest SNR and CNR, and was maximally efficient with a factors of greater than 6 as compared with conventional spin echo.

Echo-Planar Imaging↗
PubMed2000

Quantitative analysis of endothelin-1 and vasoactive intestinal contractor/endothelin-2 gene expression in rats by real-time reverse transcriptase polymerase chain reaction.

We established a real-time quantitative reverse transcriptase polymerase chain reaction (RT-PCR) system for the analysis of rat endothelin-1 (ET-1) and vasoactive intestinal contractor (VIC)/ET-2 gene expression. We used this technique to examine the expression levels in rat in 16 different organs. ET-1 gene expression was observed in all organs examined, while VIC mRNA was detected in some organs such as heart, lung, ovary, stomach, and intestine. Ovary and intestine express both ET-1 and VIC mRNA at high levels, suggesting the importance of both peptides in these organs. In addition, we examined the gene expression levels in intestinal epithelial and mesenchymal tissues from rat fetuses at 16.5 and 19.5 days postcoitus (E16.5 and E19.5). We observed distinct differences in the temporal gene expression patterns for ET-1 and VIC in fetal intestinal epithelial tissue. In fetal mesenchymal tissue the expression level of ET-1 is significantly higher than that of VIC, and the levels of both genes remain unchanged over the time period observed. These findings suggest distinct biological roles and gene regulation mechanisms for ET-1 and VIC in intestinal epithelial and mesenchymal tissues.

Animals↗
PubMed2007

Quantitative analysis of bacterial medium-chain-length poly([R]-3-hydroxyalkanoates) by gas chromatography.

Standard chromatographic methods for the quantification of bacterial poly(3-hydroxyalkanoate) (PHA) proved to be inappropriate for the analysis of medium-chain-length PHA (mcl-PHA). Transesterification catalyzed by protic acids is not quantitative for mcl-PHA under common conditions due to slow reaction kinetics and formation of side-products in case of functionalized side-chains. To circumvent these limitations, an improved method for the quantification of mcl-PHA by GC-FID was developed. Boron trifluoride in methanol was successfully applied to quantitatively methanolyse different mcl-PHA (recovery >94%). This novel method is well-suited for the analysis of purified mcl-PHA as well as for mcl-PHA in biomass.

Alkanes↗
PubMed2000

Quantitative analysis of acetates in cigarette tobacco using solid-phase microextraction and gas chromatography-mass spectrometry.

A method incorporating solid-phase microextraction (SPME) and gas chromatography-mass spectrometry for the headspace analysis of selected volatile organic compounds present in cigarette tobacco is developed and evaluated. Quantitative information on methyl, ethyl, n-propyl, isopropyl, isopropenyl, vinyl, and butyl acetates present in 29 different flavor variants (full, light, and ultra-light) of the top ten selling brands in the United States is presented. The concentrations of the various acetate analytes range from the low nanaogram to microgram levels per cigarette. Clear differences are observed in the concentrations of various acetates when comparing the levels in brands from different manufacturers. The SPME technique provides a method that allows high sample throughput, requires little sample preparation, and yields useful analytical information. High precision is obtained on multiple measurements of cigarettes from an individual pack, but lower precision levels are observed in general when comparing results obtained on the analysis of cigarettes from different packs of the same brand. The higher pack-to-pack variations may be due in part to product aging with a proportionate amount of evaporative loss of the relatively volatile acetates.

Acetates↗