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PubMed1994

[Quantitative analysis of 123I-BMIPP imaging in relation to exercise-redistribution 201Tl in patients with old myocardial infarction].

Myocardial kinetics of 123I-labeled 15-(p-iodophenyl)3R,S-methylpentadecanoic acid (BMIPP) was evaluated with BMIPP imaging in conjunction with stress-201Tl. We studied 20 patients with old myocardial infarction. BMIPP SPECT was obtained at 20 min and 3 h after injection. On a separate day, exercise stress-201Tl SPECT was performed at 10 min and 3 h after injection. Then, left ventricular myocardium was divided into 20 segments. For quantitative analysis, in each SPECT data, the maximum value (average counts per pixel) of all 20 myocardial segments was taken as 100%; the other values were calculated as a percentage of this maximum (Relative regional uptake, RRU). On the basis of stress-201Tl pattern, the myocardial segments were classified into 4 groups; normal 201Tl uptake, reversible 201Tl defect, fixed 201Tl defect and 201Tl defect with reverse redistribution. The 20 min BMIPP showed reduced activity compared with 3 h-201Tl (p < 0.001), especially in the area of 201Tl redistribution (50/111 segments, 45%), implicating impaired fatty acid utilization at resting condition. The washout rate of the segments with reversible 201Tl defect (-1.6 +/- 13.9%) was significantly lower than that of the segments with normal 201Tl uptake (9.0 +/- 9.8%) and fixed 201Tl defect (3.8 +/- 12.9%). Thus, BMIPP in combination with stress 201Tl imaging provides precise informations of impaired myocardial fatty acid utilization in patients with old myocardial infarction.

Adult↗

PubMed2006

Quantitative analysis of deuterium using laser-induced plasma at low pressure of helium.

It was proved that the analysis of deuterium can be conducted using laser-induced plasma spectroscopy. By selecting the appropriate surrounding gas, its pressure, and gating time of the detection system, it was shown that the emission lines of both hydrogen (H(alpha)) and deuterium (D(alpha)), separated by only 0.179 nm, can be fully resolved. A linear calibration curve was also obtained, indicating that this technique has the potential for quantitative analysis of deuterium. The minimum detection limit achieved in this stage of research was estimated to be 50 ppm. We have also shown that this technique can be used as a simple and rapid method for D and H analysis in solid samples.

Journal Article↗

PubMed2007

Quantitative analysis of lymphangiogenic markers in human gastroenteric tumor.

BACKGROUND: Lymphatic spread of gastroenteric tumor cells to regional lymph nodes is one of the early events in metastatic cancers and is often associated with distant metastatic spread and poor prognosis. Expression levels of newly described lymphatic endothelial markers, LYVE-1, VEGF-C, VEGF-D and the VEGF receptors VEGFR-3 were assessed in our study. METHODS: Paired (tumor and corresponding normal tissue) samples were obtained. The expression level of each factor was determined using RT-PCR and quantified by using a real-time quantitative PCR (RT-QPCR) technique, with respective cloned cDNA plasmids as internal standards. RESULTS: The expression of VEGF-C and lymphatic endothelial marker VEGFR-3 was significantly greater in patients with lymph node metastasis than in those without metastasis, but no different expression level of VEGF-D and LYVE-1 was detected in both groups of patients. Lymphatic vessel density (LVD), which was assessed by immunohistochemistry for LYVE-1, was correlated with lymphangiogenesis factors and lymph node metastasis. Expression of VEGF-C and VEGFR-3 was significantly associated with higher peritumoral LVD than normal group, and LVD was found greater in the node-positive group than in the node-negative group. CONCLUSIONS: These results indicate that quantitative analysis of lymphangiogenic marker VEGF-C and VEGFR-3 in gastroenteric specimens may be useful in predicting metastasis of gastroenteric cancer to regional lymph nodes, but the role of LYVE-1 in predicting metastasis of gastroenteric cancer requires further analysis.

Biomarkers, Tumor↗

PubMed2004

Quantitative analysis of nucleotide modulation of DNA binding by DnaC protein of Escherichia coli.

In this study, we have presented the first report of Escherichia coli DnaC protein binding to ssDNA (single stranded DNA) in an apparent hexameric form. DnaC protein transfers DnaB helicase onto a nascent chromosomal DNA replication fork at oriC, the origin of E. coli DNA replication. In eukaryotes, Cdc6 protein may play a similar role in the DNA helicase loading in the replication fork during replication initiation at the origin. We have analysed the DNA-binding properties of DnaC protein and a quantitative analysis of the nucleotide regulation of DnaC-DNA and DnaC-DnaB interactions using fluorescence anisotropy and affinity sensor analysis. DnaC protein bound to ssDNA with low to moderate affinity and the affinity was strictly modulated by nucleotides. DnaC bound ssDNA in the complete absence of nucleotides. The DNA-binding affinity was significantly increased in the presence of ATP, but not ATP[S]. In the presence of ADP, the binding affinity decreased approximately fifty-fold. Both anisotropy and biosensor analyses demonstrated that with DnaC protein, ATP facilitated ssDNA binding, whereas ADP facilitated its dissociation from ssDNA, which is a characteristic of an ATP/ADP switch. Both ssDNA and nucleotides modulate DnaB6*DnaC6 complex formation, which has significant implications in DnaC protein function. Based on the thermodynamic data provided in this study, we have proposed a mechanism of DnaB loading on to ssDNA by DnaC protein.

Adenosine Diphosphate↗

PubMed1990

Neovascularization of prosthetic vascular grafts. Quantitative analysis of angiogenesis and microhemodynamics by means of intravital microscopy.

Neovascularization of prosthetic vascular grafts seems to play an important role in the prevention of early graft failure due to infection of thrombotic occlusion. The process of angiogenesis and neovascularization was analyzed for three different prosthetic vascular grafts (PTFE, Dacron double microvelour and gelatin-coated Dacron double microvelour) in vivo by means of fluorescence microscopy. Under Nembutal anesthesia (50 mg/kg BW) Syrian golden hamsters were fitted with a dorsal skinfold chamber, which contains the cutaneous skeletal muscle as well as subcutaneous tissue, and allows for quantitative analysis of the microcirculation for a prolonged period of time. In each chamber one piece (1mm2) of all three vascular grafts was implanted. Five days after implantation neovascularization was ascertained in 9/11 (coated) and 8/11 (non-coated) Dacron grafts, while only 4/11 PTFE implants revealed new microvessels. On day 10 the density of newly-formed microvessels was significantly higher (p less than 0.001) in Dacron grafts (234.3 +/- 31.2 cm-1 and 238.9 +/- 41.3 cm-1 respectively) as compared to PTFE implants (154.9 +/- 30.4 cm-1). In addition, Dacron grafts revealed a larger neovascularization zone extending into the perigraft tissue. 12 days after implantation non-coated Dacron grafts were most tightly integrated into the perigraft tissue. The better neovascularization of Dacron might be due to the high porosity of the graft compared to low porous PTFE, which revealed insufficient neovascularization.

Animals↗

PubMed1998

[Quantitative analysis of motor unit potential in patients with dermatomyositic disease].

To diagnose dermatomyositic disease well, we adopted the method of EMG in an investigation of 37 patients. Their electrophysiologic parameters of 220 muscles were determined. The results showed that the parameters, including the average DUR, AMP, RISE, AREA, AR/AM and SI of motor unit potentials (MUPs) were significantly lower than those of the controls (P < 0.05 or P < 0.01), especially AREA and SI (P < 0.01). But no remarkable difference was found between the muscles on the two sides of the diseased extremties. These findings suggest that quantitative analysis of MUPs is of importance to diagnosis of dermatomyositic disease and the parameters such as AREA and SI may provide more valuable information.

Action Potentials↗

PubMedDate not supplied

[Quantitative analysis of corneal excisions using argon fluoride excimer laser (193 nanometers)].

Excimer lasers represent a new and distinctive class of laser-tissue interaction termed photoablation. They can ablate materials with a high degree of precision and minimal damage to surrounding structures. The argon Fluoride excimer laser, which offers the possibility of non-contact corneal cutting, has a potential for clinical application of keratorefractive surgery. Since each pulse of excimer laser etches some amounts of tissue from the cornea, the repetitive pulses focused to a narrow line can create linear excisions. In this study, a quantitative analysis of both depth and width of corneal excisions was made on cadaver eyes at a given fluence (600 mj/cm2) and a constant repetitive rate (20Hz). The amount of ablation per pulse was not constant and the excisional depth did not show a linear correlation with pulse numbers. Both the depth and width of transversal excisions were more homogenous than those of radial excisions along the entire length of ablation.

Cornea↗

PubMed1991

Retrograde neuronal labeling of motoneurons in the rat by fluorescent tracers, and quantitative analysis of oxidative enzyme activity in labeled neurons.

Extensor digitorum longus motoneurons in the rat spinal cord were identified by retrograde labeling with two fluorescent tracers, Fast blue (FB) and Nuclear yellow (NY). Labeled motoneurons had a blue fluorescent cytoplasm at 360 nm excitation wavelength with FB, and a golden-yellow fluorescent nucleus with NY on the cryostat section. Labeled motoneurons were further examined for succinate dehydrogenase activity on the same section used for identification of the motoneurons. This study demonstrates that fluorescent dyes are useful for neuroanatomical studies by the retrograde axonal transport method, and that quantitative analysis of metabolic activity in labeled motoneurons is also possible.

Amidines↗

PubMed2003

Prognostic significance of quantitative analysis of WT1 gene transcripts by competitive reverse transcription polymerase chain reaction in acute leukaemia.

We have developed a sensitive, competitive, nested reverse transcription polymerase chain reaction (RT-PCR) titration assay that quantifies the number of Wilm's tumour (WT1) gene transcripts in bone marrow (BM) and peripheral blood (PB), coupled with a competitive RT-PCR protocol for the ABL gene as control. We studied BM/PB samples from 107 acute myeloid leukaemia (AML) patients and 22 acute lymphoblastic leukaemia (ALL) patients at presentation and detected the WT1 gene in > 90% of patients by a qualitative assay. Quantitative analysis of WT1 transcript at presentation in 66 patients (52 AML, 14 ALL) correlated significantly with remission rate, disease-free survival (DFS) and overall survival (OS) (P = 0.003). WT1 levels were normalized to 105ABL transcripts. Within good and standard cytogenetic risk groups, high WT1 levels correlated with poorer outcome. Serial quantification was performed in 35 patients (28 AML, seven ALL); those with less than 103 copies of WT1 after induction and second consolidation chemotherapy had significantly better DFS and OS. Fourteen patients have relapsed with a median complete remission duration of 12 (range 4-49) months. We detected a rise in WT1 levels in nine out of 14 patients, 2-4 months before the onset of haematological relapse, whereas in the remaining five patients, WT1 levels remained persistently high during the disease course. WT1 levels were lower in PB than in BM, but mirrored changes in the BM samples and were equally informative. We suggest that WT1 is a useful molecular target to monitor minimal residual disease in acute leukaemia, especially in cases without a specific fusion gene.

Adolescent↗

PubMed1997

Significance of quantitative analysis of AML1/ETO transcripts in peripheral blood stem cells from t(8;21) acute myelogenous leukemia.

Autologous peripheral blood stem cell transplantation (PBSCT) is replacing autologous bone marrow transplantation (BMT) in the treatment of leukemia. One of the potential advantages of autologous PBSCT is the possibility that peripheral blood stem cells (PBSC) are less likely to be contaminated by leukemic cells than bone marrow grafts. However, the major problem still remains the high incidence of leukemic relapse following autologous PBSCT, which may be caused by the reinfusion of PBSC contaminated by leukemic cells. Recently, we have developed a quantitative assay using competitive reverse transcriptase polymerase chain reaction that estimates the number of AML1/ETO transcripts in t(8;21) acute myelogenous leukemia (AML), in order to determine the degree of leukemic cell contamination in PBSC harvests, and to monitor minimal residual disease (MRD) quantitatively in patients with t(8;21) AML. Our data indicate that although PBSC harvests collected after consolidation chemotherapy are contaminated by leukemic cells, the degree of leukemic cell contamination decreases with repeated cycles of chemotherapy. Furthermore, the MRD in PBSC harvests is less than in the corresponding bone marrow obtained on the day of the PBSC collection. There appears to be no relationship between the number of AML1/ETO transcripts found in the infused PBSC harvests and the incidence of leukemic relapse following autologous PBSCT in our study. However, a substantial decrease of AML1/ETO transcripts was seen following autologous PBSCT. Thus, the quantitative analysis of AML1/ETO transcripts may be clinically useful in patients with t(8;21) AML.

Blood Cells↗

PubMed2004

Assessing hematopoietic chimerism after allogeneic stem cell transplantation by multiplexed SNP genotyping using microarrays and quantitative analysis of SNP alleles.

Single-nucleotide polymorphisms (SNPs) have the potential to be particularly useful as markers for monitoring of chimerism after stem cell transplantation (SCT) because they can be analyzed by accurate and robust methods. We used a two-phased minisequencing strategy for monitoring chimerism after SCT. First, informative SNPs with alleles differing between donor and recipient were identified using a multiplex microarray-based minisequencing system screening 51 SNPs to ensure that multiple informative SNPs were detected in each donor-recipient pair. Secondly, the development of chimerism was followed up after SCT by sensitive, quantitative analysis of individual informative SNPs by applying the minisequencing method in a microtiter plate format. Using this panel of SNPs, we identified multiple informative SNPs in nine unrelated and in 16 related donor-recipient pairs. Samples from nine of the donor-recipient pairs taken at time points ranging from 1 month to 8 years after transplantation were available for analysis. In these samples, we monitored the allelic ratios of two or three informative SNPs in individual minisequencing reactions. The results agreed well with the data obtained by microsatellite analysis. Thus, we conclude that the two-phased minisequencing strategy is a useful approach in the following up of patients after SCT.

Alleles↗

PubMed2003

Quantitative analysis of continuous intracranial pressure recordings in symptomatic patients with extracranial shunts.

OBJECTIVES: To explore the outcome of management of possible shunt related symptoms using intracranial pressure (ICP) monitoring, and to identify potential methodological limitations with the current strategies of ICP assessment. METHODS: The distribution of persistent symptoms related to extracranial shunt treatment was compared before and after management of shunt failure in 69 consecutive hydrocephalic cases. Management was heavily based on ICP monitoring (calculation of mean ICP and visual determination of plateau waves). After the end of patient management, all ICP curves were re-evaluated using a quantitative method and software (Sensometrics pressure analyser). The ICP curves were presented as a matrix of numbers of ICP elevations (20 to 35 mm Hg) or depressions (-10 to -5 mm Hg) of different durations (0.5, 1, or 5 minutes). The numbers of ICP elevations/depressions standardised to 10 hours recording time were calculated to allow comparisons of ICP between individuals. RESULTS: After ICP monitoring and management of the putative shunt related symptoms, the symptoms remained unchanged in as many as 58% of the cases, with the highest percentages in those patients with ICP considered normal or too low at the time of ICP monitoring. The quantitative analysis revealed a high frequency of ICP elevations (20 to 35 mm Hg lasting 0.5 to 1 minute) and ICP depressions (-10 to -5 mm Hg lasting 0.5, 1, or 5 minutes), particularly in patients with ICP considered normal. CONCLUSIONS: The value of continuous ICP monitoring with ICP analysis using current criteria appears doubtful in the management of possible shunt related symptoms. This may reflect limitations in the strategies of ICP analysis. Calculation of the exact numbers of ICP elevations and depressions may provide a more accurate description of the ICP profile.

Adolescent↗

PubMed2002

Expression of aldosterone synthase gene in failing human heart: quantitative analysis using modified real-time polymerase chain reaction.

We have shown that aldosterone, previously thought to be synthesized solely in the adrenal cortex, is also produced in the failing human heart. One way to induce aldosterone synthesis in the heart would be to increase the expression of CYP11B2, the enzyme catalyzing the terminal step in aldosterone synthesis. However, CYP11B2 expression has never been examined in cardiac tissue from patients with heart failure. We assayed CYP11B2 expression in left ventricular tissue obtained at autopsy from seven patients. Total RNA was extracted from frozen samples. CYP11B2 gene expression was then quantitatively analyzed using a modified real-time PCR method that enabled assay of samples containing very small amounts of template DNA. The template DNA was initially amplified 1024-fold by subjecting it to 10 PCR cycles in the absence of the TaqMan probe. Thereafter, conventional real-time PCR was simultaneously performed on both target and standard samples. We measured the small quantities of CYP11B2 gene transcript and found the levels to be significantly higher in samples from heart failure patients than in those from cardiovascular disease-free patients. Our modified real-time PCR method enables quantitative analysis of gene expression using very small amounts of template DNA. CYP11B2 expression is up-regulated in the failing human heart.

Cytochrome P-450 CYP11B2↗

PubMed2005

Quantitative analysis of ultrasensitive responses.

Ultrasensitive responses are common in cellular information transfer because they allow cells to decode extracellular stimuli in an all-or-none manner. Biochemical responses are usually analyzed by fitting the Hill equation, and the estimated Hill coefficient is taken as a measure of sensitivity. However, this approach is not appropriate if the response under consideration significantly deviates from the best-fit Hill equation. In addition, Hill coefficients greater than unity do not necessarily imply ultrasensitive behaviour if basal activation is significant. In order to circumvent these problems we propose a general method for the quantitative analysis of sensitivity, the relative amplification plot, which is based on the response coefficient defined in metabolic control analysis. To quantify sensitivity globally (i.e. over the whole stimulus range) we introduce the integral-based relative amplification coefficient. Our relative amplification approach can easily be extended to monotonically decreasing, bell-shaped or nonsaturated responses.

Cells↗

PubMed1985

Comparison of the thin layer chromatography/flame ionization detection system with other methods for the quantitative analysis of liver lipid contents in alcohol-fed rats and controls.

In this study, we have examined the feasibility of using the Thin Layer Chromatography/Flame Ionization Detection (TLC/FID) system to evaluate the lipid content of alcohol-induced fatty liver by comparing the results with those from other methods. Various amounts of standards (tripalmitin, phosphatidylcholine and cholesterol) were spotted on Chromarods and scanned either with or without development in a solvent system. The detector responses were significantly greater when the spots were not developed. From the results with developed rods, conversion factors (amount/area) were calculated. These were used for the quantitative analysis of the liver lipids from rats fed a Lieber-DeCarli ethanol diet or a control diet for four weeks. The triglyceride (TG), phospholipid (PL), cholesterol (CH) and cholesterol ester (CE) contents (65.9, 25.4, 2.9 and 6.8 mg/g, respectively) obtained by the TLC/FID system were similar to those observed by other methods (67.9, 27.6, 3.0 and 8.3 mg/g, respectively). The liver lipid content in control rats also was similar to that obtained by other methods (TG, 19.0 vs 20.6; PL, 24.2 vs 21.8, CH, 2.1 vs 2.1 and CE, 1.8 vs 2.6 mg/g). Thus, the magnitude of changes in liver lipid levels due to chronic alcohol ingestion obtained by alternate methods also was found with TLC/FID. The TLC/FID system provides a convenient method for rapid analysis of the extent of fatty liver in alcohol-fed animals.

Animals↗

PubMed2003

Hairy cell leukemia: early immunophenotypical detection and quantitative analysis by flow cytometry.

UNLABELLED: The abnormal coexpression of the so-called 'HCL-restricted' markers (CD22+CD11c, CD25 and CD103) identified on monotypic, slightly large B-lymphocytes in the large cell-gate of dot-plots has previously been shown to be highly characteristic of hairy cell leukemia (HCL). The main aim of our present study was to determine if patterns with low levels of neoplastic cells in bone marrow (BM) or peripheral blood (PB) are of a value the early diagnosis and/or detection of minimal residual disease (MRD) in HCL. Next we wished to determine if quantitative immunophenotyping given by molecules of equivalent soluble fluoresceine (MESF) could help to distinguish pathologic B-lymphocytic pool from that of normal residual B-cells also in patients with low numbers of HCL cells. The abnormal immunophenotypes were studied in 174 specimens from 19 patients with suspect HCL or during follow-up of already treated patients. For evaluation of marker density fluorescent calibration microbeads were used. In 12 HCL patients (67%) permanent complete remission was observed after treatment. In 6 patients (33%) transient MRD+ phenotype was identified but the clinical manifestation of relapse was followed till now in only three patients. One patient was phenotyped just only at diagnosis. The pathological cells in low levels were found in 5 patients at diagnosis (in the range from 2 to 12%) and in patients with MRD+ phenotype they were recognized repeatedly in the range from 2 to 8%. Furthermore, we observed in hairy cells significantly higher values of molecule numbers of some B-cell markers, comparing to that of residual B-cells in nonleukemic lymphocyte gate of the same sample. We found profound and persistent CD4+ lymphopenia in all but one studied patients after CdA treatment. CONCLUSIONS: Flow cytometric immunophenotyping of PB and BM is highly sensitive and specific method and is capable to detect low levels of malignant cells in HCL. Quantitative analysis of MESF values of pathological B-cells comparing to normal residual B-cells seems to be another new marker of HCL in common, which is reliable detecting also small cell numbers in examined sample. A long-term decline of CD4+ T-cells correlated with the relatively low incidence of clinical progression of HCL.

Antigens, CD↗

PubMed2001

Quantitative analysis of the principle soy isoflavones genistein, daidzein and glycitein, and their primary conjugated metabolites in human plasma and urine using reversed-phase high-performance liquid chromatography with ultraviolet detection.

Soy isoflavones are becoming of increasing interest as nutritional agents which can be used to combat osteoporosis and hyperlipidemia, and are also being considered as potential cancer chemopreventive compounds. However, prior to their formulation and distribution as therapeutic agents, thorough pharmacokinetic and toxicological assessment needs to be completed in men and women in a variety of health conditions in order to ensure their therapeutic efficacy and safety. At this time, studies of purified soy isoflavones are possible, and are being designed to fully evaluate the pharmacological utility of these preparations. In support of these studies, quantitative analysis of soy isoflavones in biological fluids can be accomplished with a wide variety of methods and analytical instrumentation. However, the relatively ubiquitous presence of high-performance liquid chromatography with ultraviolet detection (HPLC-UV) in most analytical laboratories, the relative ease of its operation, and the lesser expense of this instrumentation as compared to more sophisticated techniques such as liquid chromatography-mass spectrometry, offers some distinct advantages for its use in pharmacokinetic studies. In this manuscript, the development and validation of an HPLC-UV method for the quantitation of the principal soy isoflavones, genistein, daidzein, and glycitein, and their primary metabolites, in human plasma and urine is described. This analytical approach allows for pharmacologically relevant concentrations of the analytes and their principle metabolites to be detected, and has been validated in close agreement with the US Food and Drug Administration's guidelines for the validation of methods to be used in support of pharmacokinetic studies.

Chromatography, High Pressure Liquid↗

PubMed2003

Quantitative analysis of lacrimal gland function, apoptotic figures, Fas and Fas ligand expression of lacrimal glands in dry eye patients.

The purpose of our study was to examine the correlation between the lacrimal gland function and apoptotic figure, Fas and Fas ligand (FasL) expression in the lacrimal gland. A total of 15 dry eye patients (nine Sjögren's syndrome and six non-Sjögren's syndrome-type dry eye) were recruited for the study. Lacrimal function was evaluated by Schirmer tests 1 and 2. Lacrimal gland biopsies were performed and sections were analyzed by immunohistochemistry using APO2.7, an antibody to Fas and FasL. Quantitative analysis of fluorescein staining was performed by a scanning laser microscopy. Schirmer test 2 results were lower in Sjögren's syndrome-type dry eye and were associated with positive staining of acinar cells with APO2.7 and of infiltrating lymphocytes with FasL. There was a good correlation between the results of Schirmer test 2 and APO2.7 and FasL staining. Lacrimal gland dysfunction is related to the apoptotic figure of acinar cells possibly induced by FasL on the infiltrating lymphocytes.

Adult↗