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At least 883 records · Page 49Linked to original sources
PubMed2001

Quantitative analysis of MR images in asphyxiated neonates: correlation with neurodevelopmental outcome.

BACKGROUND AND PURPOSE: MR imaging has been shown to be of prognostic significance in the evaluation of asphyxiated neonates. The purpose of this project was to determine whether the use of intensity ratios in key regions of the brain might better detect regions of injured brain and thus improve the correlation of imaging findings with 12-month neurodevelopmental outcome. METHODS: Prospectively acquired MR studies of 53 asphyxiated neonates were reviewed retrospectively. Signal intensities from standard T1- and T2-weighted images of seven major brain regions that are affected in asphyxia were measured. Intensity ratios were calculated by dividing the signal intensity of each brain region by the signal intensity of the ocular vitreous. The intensity ratios were then correlated with 12-month neurodevelopmental outcome. These results were compared with correlations determined by a qualitative scoring system. RESULTS: The only significant statistical correlation between the intensity ratios and 12-month neurodevelopmental outcome were those of anterior watershed injury with the Mental Development Index of the Bayley Scales of Infant Development II. The qualitative measurements showed a strong correlation with many outcome parameters. CONCLUSION: Standard qualitative assessment is more predictive of neurodevelopmental outcome than is quantitative analysis. This finding most likely reflects the inability of the quantitative assessment of intensity ratios to compensate for the day-to-day evolution of signal intensity of the injured neonatal brain. Anterior watershed injury may be predictive of abnormal cognitive outcome; examination of these patients at age 30 months will be important to determine the accuracy of this observation.

Asphyxia Neonatorum↗
PubMed2000

Quantitative analysis of long-chain trans-monoenes originating from hydrogenated marine oil.

Gas chromatography (GC) is used for the analysis of trans-fatty acids in partially hydrogenated vegetable oils. Although trans-isomers of C18 carbon length predominate in partially hydrogenated vegetable oils, trans-isomers of C20 and C22 carbon length occur in partially hydrogenated fish oil. We report a simple silver ion chromatographic combined with capillary GC technique for quantitative analysis of trans-monoenes derived from partially hydrogenated fish oil. Silver nitrate thin-layer chromatographic (TLC) plates are developed in toluene/hexane (50:50, vol/vol). Fatty acid methyl esters are separated into saturates (Rf 0.79), trans-monoenes (Rf 0.49), cis-monoenes (Rf 0.27), dienes (Rf 0.10), and polyunsaturated fatty acids with three or more double bonds remaining at the origin. The isolated trans-monoenes are quantitatively analyzed by capillary GC. The technique of argentation TLC with GC analysis of isolated methyl esters is highly reproducible with 4.8% variation (i.e., coefficient of variation, CV%) in R. values and 4.3 and 6.9% CV% in quantification within batch and between batch, respectively. Furthermore, the combined technique revealed that direct GC analysis underestimated the trans-content of margarines by at least 30%. In this study, C20 and C22 trans-monoenes were found in relatively large quantities; 13.9% (range 10.3-19.6%) and 7.5% (range 5.3-11.5%), respectively, in margarine purchased in 1995, but these C20 and C22 trans-monoenes were much reduced (0.1%) in a fresh selection of margarine purchased in 1998. Compositional data from labels underestimated the trans-content of margarines, especially those derived from hydrogenated marine oil. Low levels of C20 transmonoenes (range 0.1-0.3%) and C22 trans-monoenes (range 0.0-0.1%) were identified in adipose tissue obtained from healthy volunteers in 1995, presumably indicating consumption of partially hydrogenated fish oil.

Adipose Tissue↗
PubMed1993

Quantitative analysis of distribution and fate of human lung cancer emboli labeled with 125I-5-iodo-2'-deoxyuridine in nude mice.

The chemical and radio toxicity of 125-5-iodo-2'-deoxyuridine (125IUDR) on 870127T human lung cancer (HLC) cells grown in tissue cultures and the quantitative analysis of the distribution and fate of 125IUDR-labeled 870127T HLC cells in nude mice were evaluated. After 870127T HLC cells were plated and 125IUDR was added to the dishes at levels ranging from 0.1 microCi/ml to 5.0 microCi/ml of media, the growth rate of the cells for 24 h was similar to that of non-labeled cells. Nude mice were given intravenous injections of 125IUDR labeled 870127T HLC cells and killed at various intervals ranging from 5 min to 24 h after injection. Organs were collected, processed, and monitored. The lung contained most of the tumor cells at all intervals and the number of tumor cells in the lung decreased gradually post-injection. The tumor cells died rapidly, and only about 1.5% of all cell survived after 24 h post-injection. This study confirmed that very few surviving tumor cells are needed to cause metastasis.

Adenocarcinoma↗
PubMed1994

A qualitative and quantitative analysis of the response of the retinal ganglion cell soma after stretch injury to the adult guinea-pig optic nerve.

The development of a model for focal axonal injury in the optic nerve of the adult guinea-pig has allowed a qualitative and quantitative analysis of the response of the retinal ganglion cell soma to this type of injury. Large and medium sized retinal ganglion cells show classic 'central chromatolysis' in about 30% of ganglion cells between three and seven days after injury, a high proportion of which undergo degeneration between seven and 14 days. Small ganglion cells and small neurons do not demonstrate any morphological response to stretch injury of the optic nerve. However, a small number of larger ganglion cells demonstrate enlargement of the cell soma and nucleolus together with reconstitution of the rough endoplasmic reticulum between seven and 14 days after stretch injury. We suggest that these cells are either recovering from or regenerating after a non-disruptive lesion to their axons. We suggest that some of these morphological changes parallel documented regenerative responses in peripheral/extrinsic neurons after injury to their axons. We conclude that the time course of the 'axon reaction' after stretch injury to axons is longer than that obtained after crush or transection. We provide good morphological evidence that the level of injury after application of non-disruptive mechanical strain to axons is less severe than in the former two models of axonal injury and that a proportion of damaged neurons do not die but rather demonstrate either/or recovery or a regenerative response.

Animals↗
PubMed2004

High throughput quantitative analysis of serum proteins using glycopeptide capture and liquid chromatography mass spectrometry.

It is expected that the composition of the serum proteome can provide valuable information about the state of the human body in health and disease and that this information can be extracted via quantitative proteomic measurements. Suitable proteomic techniques need to be sensitive, reproducible, and robust to detect potential biomarkers below the level of highly expressed proteins, generate data sets that are comparable between experiments and laboratories, and have high throughput to support statistical studies. Here we report a method for high throughput quantitative analysis of serum proteins. It consists of the selective isolation of peptides that are N-linked glycosylated in the intact protein, the analysis of these now deglycosylated peptides by liquid chromatography electrospray ionization mass spectrometry, and the comparative analysis of the resulting patterns. By focusing selectively on a few formerly N-linked glycopeptides per serum protein, the complexity of the analyte sample is significantly reduced and the sensitivity and throughput of serum proteome analysis are increased compared with the analysis of total tryptic peptides from unfractionated samples. We provide data that document the performance of the method and show that sera from untreated normal mice and genetically identical mice with carcinogen-induced skin cancer can be unambiguously discriminated using unsupervised clustering of the resulting peptide patterns. We further identify, by tandem mass spectrometry, some of the peptides that were consistently elevated in cancer mice compared with their control littermates.

Animals↗
PubMed2001

Quantitative analysis of mRNA amplification by in vitro transcription.

Effective transcript profiling in animal systems requires isolation of homogenous tissue or cells followed by faithful mRNA amplification. Linear amplification based on cDNA synthesis and in vitro transcription is reported to maintain representation of mRNA levels, however, quantitative data demonstrating this as well as a description of inherent limitations is lacking. We show that published protocols produce a template-independent product in addition to amplifying real target mRNA thus reducing the specific activity of the final product. We describe a modified amplification protocol that minimizes the generation of template-independent product and can therefore generate the desired microgram quantities of message-derived material from 100 ng of total RNA. Application of a second, nested round of cDNA synthesis and in vitro transcription reduces the required starting material to 2 ng of total RNA. Quantitative analysis of these products on Caenorhabditis elegans Affymetrix GeneChips shows that this amplification does not reduce overall sensitivity and has only minor effects on fidelity.

Animals↗
PubMed1998

Extrastriate feedback to primary visual cortex in primates: a quantitative analysis of connectivity.

Knowledge-based or top-down influences on primary visual cortex (area V1) are believed to originate from information conveyed by extrastriate feedback axon connections. Understanding how this information is communicated to area V1 neurons relies in part on elucidating the quantitative as well as the qualitative nature of extrastriate pathway connectivity. A quantitative analysis of the connectivity based on anatomical data regarding the feedback pathway from extrastriate area V2 to area V1 in macaque monkey suggests (i) a total of around ten million or more area V2 axons project to area V1; (ii) the mean number of synaptic inputs from area V2 per upper-layer pyramidal cell in area V1 is less than 6% of all excitatory inputs; and (iii) the mean degree of convergence of area V2 afferents may be high, perhaps more than 100 afferent axons per cell. These results are consistent with empirical observations of the density of radial myelinated axons present in the upper layers in macaque area V1 and the proportion of excitatory extrastriate feedback synaptic inputs onto upper-layer neurons in rat visual cortex. Thus, in primate area V1, extrastriate feedback synapses onto upper-layer cells may, like geniculocortical afferent synapses onto layer IVC neurons, form only a small percentage of the total excitatory synaptic input.

Animals↗
PubMed2004

The coupling of supercritical fluid chromatography and field ionization time-of-flight high-resolution mass spectrometry for rapid and quantitative analysis of petroleum middle distillates.

We report the first coupling of supercritical fluid chromatography (SFC) with field ionization time-of-flight high-resolution mass spectrometry (FI-ToF HRMS), in parallel with ultraviolet (UV) detection and flame ionization detection (FID), for rapid and quantitative analysis of petroleum middle distillates. SFC separates petroleum middle distillates into saturates and 1- to 3-ring aromatics. FI generates molecular ions for hydrocarbon species eluted from the SFC. The high resolution and exact mass measurements by ToF mass spectrometry provide elemental compositions of the molecules in the petroleum product. The amounts of saturates and aromatic ring types were quantified using the parallel SFC-FID assisted by SFC-UV. With a proper carbon-number calibration, the detailed composition of the petroleum middle distillate was rapidly determined.

Journal Article↗
PubMed1997

[Quantitative analysis of E-cadherin expression and clinicopathologic evaluation in gastric cancer].

OBJECTIVE: To evaluate the relationship of E-cadherin (E-CD) expression to cellular DNA content and biological behavior of gastric cancer. METHODS: E-CD expression and cellular DNA content were quantitatively measured by flow cytometry and immunofluorescence methods in 80 cases of formalin-fixed, paraffin-embedded gastric cancer. Systematic pathological examinations and follow up were performed for all cases. RESULTS: E-CD expression was significantly reduced in all cases of gastric cancer, fluorescence Index (FI) of E-CD expression was 0.67 +/- 0.11 in gastric cancer, 1.0 +/- 0.07 in normal gastric mucosa (P < 0.001). The reduction of E-CD expression was also found in 2 cases of early gastric cancer. Tumors with a decrease in E-CD expression occurred significantly more frequently in undifferentiated, diffuse growth pattern Borrmann 4 type, positive lymph node (LN) metastasis and infiltrated serosa type gastric cancer, of which survival time was within 5 years (P < 0.001). E-CD expression was also reduced in gastric cancer with the number of LN metastasis above 5, metastasis to more than group 2. E-CD expression was lower in uneuploid cancer than that in diploid cancer (P < 0.01). The value of DI and PI with negative E-CD expression was significantly higher than that of positive E-CD expression (P < 0.01). CONCLUSION: Down-regulation of E-CD expression correlates with bad biological behavior and poor prognosis of gastric cancer. The reduction of E-CD expression may take place during early time of gastric cancer. Quantitative analysis of E-CD expression may have some value in evaluating the intensity of LN metastasis of gastric cancer.

Cadherins↗
PubMed2005

Simulation of realistic abnormal SPECT brain perfusion images: application in semi-quantitative analysis.

Simulation is useful in the validation of functional image analysis methods, particularly when considering the number of analysis techniques currently available lacking thorough validation. Problems exist with current simulation methods due to long run times or unrealistic results making it problematic to generate complete datasets. A method is presented for simulating known abnormalities within normal brain SPECT images using a measured point spread function (PSF), and incorporating a stereotactic atlas of the brain for anatomical positioning. This allows for the simulation of realistic images through the use of prior information regarding disease progression. SPECT images of cerebral perfusion have been generated consisting of a control database and a group of simulated abnormal subjects that are to be used in a UK audit of analysis methods. The abnormality is defined in the stereotactic space, then transformed to the individual subject space, convolved with a measured PSF and removed from the normal subject image. The dataset was analysed using SPM99 (Wellcome Department of Imaging Neuroscience, University College, London) and the MarsBaR volume of interest (VOI) analysis toolbox. The results were evaluated by comparison with the known ground truth. The analysis showed improvement when using a smoothing kernel equal to system resolution over the slightly larger kernel used routinely. Significant correlation was found between effective volume of a simulated abnormality and the detected size using SPM99. Improvements in VOI analysis sensitivity were found when using the region median over the region mean. The method and dataset provide an efficient methodology for use in the comparison and cross validation of semi-quantitative analysis methods in brain SPECT, and allow the optimization of analysis parameters.

Adult↗
PubMed2005

Qualitative and quantitative analysis of angiogenetic factors in transitional cell bladder carcinoma: relationship with clinical course at 10 years follow-up.

Many authors have shown that tumor hypoxia exerts its own influence on malignant progression by inducing angiogenetic factors and new blood vessels inside and around the tumor. This event usually suggests a poor prognosis and/or aggressive tumor behavior. The objective of the present study is to compare molecular analysis of angiogenetic factors with microvessel density (MVD) in bladder carcinoma. Twenty-nine consecutive patients underwent transurethral or open surgery for bladder tumors. Neoplastic tissue samples, normal-appearing bladder mucosa and blood samples were taken from each patient. All the tissues underwent mRNA extraction and Northern blot analysis, marked with specific probes for inducible nitric oxide sinthase (iNOS), cyclo-oxygenase-2 (cox-2), vascular endothelial growth factor (VEGF) and were evaluated by gel-electrophoresis. Microvessel density, a quantitative analysis for neoangiogenesis, was also evaluated by using CD31 immunohistochemical assay and compared with both molecular analysis and patient follow-up. Two follow-up for recurrence and/or progression were performed at 74 months and 10 years from surgery respectively. Pathological evaluation demonstrated the presence of superficial transitional cell carcinoma (sTCC) in 15 patients, while 14 had an invasive bladder tumor (iBT). At both 74 months and 10 years follow-up, all patients with lower MVD had a shorter survival time. No significant results were obtained by comparing disease progression or survival rate with VEGF, iNOS and COX-2 levels. A proportional increase of VEGF expression and MVD compared with poor prognosis was the expected outcome of our study. These results were disregarded at both the 1st and the 2nd follow-up. A strong association between MVD>20 and survival rate was noted both in sTCC (p=0.024) and iBT (p>0.001) patients. These results confirm that MVD could be considered a good prognostic factor. The angiogenetic cytokines overexpression found in control tissue samples of sTCC could have clinical significance, either as a macroscopically unidentified diffuse carcinogenetic process or the presence of a systemic immune-response against tumor cells.

Aged↗
PubMed1992

Postnatal development of tyrosine hydroxylase immunoreactive amacrine cells in the rabbit retina: II. Quantitative analysis.

Tyrosine hydroxylase (TH)-immunoreactive (IR) amacrine cells of the rabbit retina mature during the first four postnatal weeks, and their cellular development is described in the preceding paper (Casini, G., and N.C. Brecha, J. Comp. Neurol. 326:283-301, 1992). The present investigation is a quantitative analysis of the postnatal development of the TH-IR amacrine cell population. TH-IR amacrine cells gradually increase in size from birth (soma area of 44.7 +/- 12.4 microns2, mean +/- standard deviation) to adulthood (144.2 +/- 28.0 microns2). Cell density slightly increases from postnatal day (PND) 0 (41.9 +/- 9.5 cells/mm2) to PND 6 (47.2 +/- 7.2 cells/mm2), then markedly decreases from PND 6 to adulthood (17.8 +/- 5.3 cells/mm2) as a consequence of retinal growth. TH-IR cell number almost doubles from PND 0 (about 4,100 cells/retina) to adulthood (about 7,850 cells/retina). The increase in the total number of TH-IR amacrine cells can be explained by the generation of new TH-IR cells in the inner nuclear layer, a delay in the expression of the TH phenotype after neurogenesis by cells committed to be dopaminergic, or the acquisition of this dopaminergic phenotype by uncommitted cells. The development of the TH-IR amacrine cell mosaic was assessed by an evaluation of the distribution of nearest neighbor distances of TH-IR cells. There is a poor correlation between this distribution and a theoretical nonrandom distribution before PND 12. After this age, the nearest neighbor distance distribution shifts towards a nonrandom distribution, and is similar to that of the TH-IR amacrine cell population in the adult retina. The establishment of the TH-IR amacrine cell population mosaic is likely to be achieved through different interacting events, including intrinsic (e.g., genetic) factors, environmental influences, and nonuniform retinal growth. Overall, the population parameters analyzed in the present study approach adult values about the time of eye opening (PND 12) and they reach adult values by PND 26.

Animals↗
PubMed1994

Localization of the two major allergens in rye-grass pollen using specific monoclonal antibodies and quantitative analysis of immunogold labelling.

The intracellular localization of the two major allergens, Lol p I and Lol p IX, in rye-grass anthers was examined using monoclonal antibodies FMCA1 (specific for Lol p I) and FMCA7 (specific for Lol p IX) with immunocytochemical techniques and quantitative analysis. A newly developed anhydrous fixation technique in a mixture of glutaraldehyde, paraformaldehyde and 2,2-dimethoxypropane followed by embedding in LR Gold resin resulted in both improved infiltration of pollen grains compared with existing techniques and the localization of these water-soluble antigens in their original sites compared with diffusion artefacts following aqueous methods. After anhydrous fixation, Lol p I was predominantly located in the electron-opaque regions of the cytosol of the vegetative cell of the tricellular pollen grains (24 counts microns-2), whereas Lol p IX was detected mainly within starch granules (16 counts microns-2). For both Lol p I and Lol p IX, similar labelling was detected in the cells of the endothecium and middle layer (18 counts microns-2), but none was found in the tapetal cells or orbicules.

Allergens↗
PubMed1990

Management of patients with symptomatic gallstones: a quantitative analysis.

Should persons with symptomatic gallstones (i.e., those that have caused biliary pain) be treated immediately? Or may they be managed expectantly until pain recurs or a biliary complication (i.e., acute cholecystitis or pancreatitis) occurs? To assess the mortality risk of different strategies, we performed a quantitative analysis. For the expectant management strategy that requires surgery only if a biliary complication occurs, the cumulative lifetime probability of gallstone disease death in a 30-year-old man is about 2%, and most deaths occur after age 65. In comparison, elective cholecystectomy has only a 0.1% rate of gallstone disease death, but all deaths occur at age 30. The average amount of life expectancy gained by immediate cholecystectomy compared with expectant management is 52 days, which is reduced to 23 days using 5% discounting. This gain could be increased only slightly by a 100% effective and risk-free therapy such as perfected lithotripsy or medical dissolution. Results are similar for women. The results suggest that, for persons with symptomatic gallstones, the life expectancy gain of immediate cholecystectomy is relatively small and that the potential incremental gain of nonsurgical therapy is also small. For patients and physicians who believe that life expectancy is of primary consideration, the decision about therapy may be made primarily on non-mortality considerations. Some patients and physicians may decide that the risk of symptomatic gallstones is low enough that a policy of expectant management may be acceptable.

Adult↗
PubMed2002

Toward a quantitative analysis of skin lesion images.

Melanoma is the most dangerous form of skin cancer. Skin cancers, and particularly melanomas, can be easily cured if detected early. The regularity of the pigment network structure is a significant sign for early diagnosis of melanoma. We present here a quantitative analysis of the morphology of the pigment network structure. Our method is based on the extraction of the pigment network structure using digital image processing techniques. Once the network is extracted, it is possible to derive statistical indicators relative to its regularity or irregularity. We report experiments on a database of 14 images, showing the effectiveness of our method.

Diagnostic Imaging↗
PubMed2003

Quantitative analysis of betulinic acid in mouse, rat and dog plasma using electrospray liquid chromatography/mass spectrometry.

Betulinic acid is under development as a therapeutic agent for the treatment of metastatic malignant melanoma. In support of pharmacokinetic and toxicological evaluations, a robust assay based on liquid chromatography/mass spectrometry (LC/MS) was developed for the quantitative analysis of betulinic acid. Sample preparation consisted of deproteinization of the plasma by the addition of three volumes of acetonitrile and one volume of methanol followed by centrifugation. Aliquots of the supernatant were analyzed using an isocratic reversed-phase high-performance liquid chromatography (HPLC) system coupled to a negative ion electrospray mass spectrometer. Deprotonated molecules of betulinic acid and the isomeric internal standard oleanolic acid were detected using selected ion monitoring at m/z 455. The limit of detection of betulinic acid was 0.5 pg (1.1 fM) injected on-column (50 pg/mL, 10 microL injection volume), and the limit of quantitation was 2 pg (4.4 fM, 200 pg/mL, 10 microL injection volume). Betulinic acid was stable in plasma samples at -20 degrees C for at least 3 weeks. The intra-day and inter-day coefficients of variation of the assay were < or =6.4 and < or =9.0%, respectively. The utility of the assay was demonstrated by analyzing betulinic acid spiked into mouse, rat and dog plasma, by determining the extent of binding of betulinic acid to plasma proteins, and by measuring betulinic acid in mouse and rat plasma following intraperitoneal or intravenous administration in vivo. At 15 and 25 microg/mL in mouse, rat or dog plasma, betulinic acid was 99.99% bound to serum proteins, and, at 5 microg/mL, betulinic acid was > or =99.97% bound.

Animals↗
PubMed1993

Quantitative analysis of revascularisation and new bone formation in experimental bone grafts. The use of an image input and processing system.

Revascularisation and new bone formation in bone grafts has been extensively studied by histological techniques, but the images obtained are very complex and consequently difficult to evaluate quantitatively. We report similar analyses in experimental bone grafts using newer computerised digital techniques. Fresh autografts and fresh and frozen allografts were used. The histological analogue images from them were input digitally into an image processor. The amount of revascularisation and new bone formation could then be quantified in the different grafts. This system has proved to be a useful method of evaluation which could be applied to the quantitative analysis of other histological images.

Angiography↗
PubMed1979

Quantitative analysis of lymphoid cells in myocosis fungoides, Sézary's syndrome and parapsoriasis en plaques.

Semi-thin sections are superior to paraffin sections for differentiating lymphoid cells. To test their possible significance in the diagnosis of cutaneous T-cell lymphomas, the following investigation was made: A quantitative analysis of lymphoid cells in the cellular infiltrate of cutaneous lesions of mycosis fungoides (11 cases), Sézary's syndrome (9 cases), and parapsoriasis en plaques (14 cases) was made using semi-thin sections of epon-embedded biopsies. As controls biopsies of patch test reactions, contact dermatitis, initial psoriasis, and erythema chronicum migrans were studied. A high percentage of Lutzner (Sézary) cells was consistently found in Sézary's syndrome and occasionally in parapsoriasis en plaques only. In mycosis fungoides lymphocytoid cells with the nuclei less dense than in normal lymphocytes were predominant. In most tumorous lesions of mycosis fungoides and of Sézary's syndrome an increased percentage of immunoblasts was noted. Normal lymphocytes were the most frequent cell type in parapsoriasis en plaques as well as in the controls. These findings may prove helpful in the diagnosis of problem cases, for which the use of semi-thin sections is recommended.

Cell Nucleus↗