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At least 1,081 records · Page 60Linked to original sources
PubMed2004

Quantitative analysis of expression of NeuroD, GAP43 and receptor tyrosine kinase B in developing mouse olfactory neuroepithelium.

OBJECTIVE: The mammalian olfactory neuroepithelium (OE), which harbors olfactory receptor neurons (ORNs), has the unusual characteristic of continuous neurogenesis throughout its lifetime. This unique feature provides an excellent model for neuronal differentiation. Recently, we found dual-phase expression of NeuroD, a member of the basic helix-loop-helix transcription factor family, in the developing mouse OE, suggesting multiple roles of NeuroD during the development of mammalian ORNs. MATERIAL AND METHODS: In order to better understand the molecular mechanism of the development of ORNs, we performed quantitative analysis of expression of NeuroD, GAP43 and receptor tyrosine kinase B (TrkB), as well as 5-bromo-2'-deoxyuridine (BrdU)-labeled cells, in the developing mouse OE from gestational Day 10 to postnatal Day 28. RESULTS: During the embryonic period, NeuroD expression is mostly confined to the basal compartment. During the neonatal period, NeuroD expression is detected in two compartments: the middle compartment and the basal compartment. GAP43-expressing cells were located between these two NeuroD-positive layers. TrkB-expressing cells were located above the NeuroD-positive layer in the middle compartment. As the mice grew, the numbers of NeuroD-expressing cells and BrdU-labeled cells in the basal compartment significantly decreased, while the number of NeuroD-expressing cells in the middle compartment gradually increased. The number of TrkB-expressing cells dramatically increased. The number of GAP43-expressing cells also gradually increased. However, the relative proportion of GAP43 cells decreased as the OE developed. CONCLUSION: NeuroD is a useful molecular marker for studying olfactory neurogenesis.

Animals↗
PubMed1997

Quantitative analysis of jaw and hyolingual muscle activity during feeding in the lizard Agama stellio

The activity of jaw and hyolingual muscles during the entire feeding sequence is examined in the lizard Agama stellio, with special focus on the intraoral transport and swallowing stages. Correlation of electromyography (EMG) data with kinematics shows that the kinematic phases (slow opening, SO; fast opening, FO; fast closing, FC; slow closing/power stroke, SC/PS) are characterised by distinct activities in the jaw and hyolingual muscles. The SO phase is clearly the result of tongue protraction (upon protraction, the tongue is pulled against the prey and consequently the lower jaw is pushed down), whereas the FO phase is caused by activity in the jaw opener and dorsal cervical muscles. Both the FC and SC/PS phases are characterised by pronounced activity in the jaw adductor muscles. Tongue retraction is produced by activity in the hyoid and tongue retractor muscles. A quantitative analysis of time-related EMG data shows that, in accordance with the kinematic analyses, three different stages can be recognised as components of the feeding cycle: prey capture, intraoral transport and swallowing. However, analysis of intensity-related data allowed a fourth stage, crushing, to be detected. Whereas there are indications that prey capture, intraoral transport and swallowing are controlled by different motor patterns, the differences between crushing and transport are likely to be caused by feedback mechanisms. Our results show the importance of including intensity-related data in quantitative analyses of EMG recordings in order to discriminate between feeding stages. Additionally, it is shown that both the jaw and the hyolingual muscles play crucial roles during feeding. During all stages, movements of the hyolingual apparatus are an essential part of the feeding cycle. Thus, when examining lizard feeding mechanisms, the activity patterns of the hyolingual muscles should not be neglected.

Journal Article↗
PubMed2005

Microsurgical anatomy and quantitative analysis of the transtemporal-transchoroidal fissure approach to the ambient cistern.

OBJECTIVE: Surgical approaches to ambient cistern lesions are complex. We investigated the microanatomy of the transtemporal-transchoroidal fissure approach to the ambient cistern with emphasis on exposure of the posterior cerebral artery. METHODS: Dissections were performed bilaterally in five silicone-injected cadaveric heads. Critical anatomic distances, specifically with reference to the P2 segment of posterior cerebral artery in relation to the inferior choroidal point and P2-P3 junction, were measured with digital calipers. Other landmarks (temporal lobe tip, points from the temporal base to the choroidal fissure) were included for quantitative analysis. RESULTS: The transtemporal-transchoroidal fissure approach provided adequate exposure of the ambient cistern, minimized temporal lobe retraction, and allowed assessment of regional microanatomy. The mean distance from the temporal base to the choroidal fissure measured 18.09 mm (range, 16.9-21.9 mm). The distances from the choroidal fissure to P2 varied at the coronal plane of the inferior choroidal point (mean, 6.96 mm; range, 3.6-12.0 mm) and the P2-P3 junction (mean, 6.02 mm; range, 4.3-6.9 mm), respectively. CONCLUSION: The transtemporal-transchoroidal fissure approach provides a corridor to the ambient cistern and P2-P3 junction while minimizing temporal lobe retraction and avoiding interruption of temporal lobe venous drainage. Because of widely variable vascular anatomy, access to posterior cerebral artery lesions using this approach requires preoperative imaging to identify the specific location of the P2-P3 junction.

Arachnoid↗
PubMed2004

Semi-automated, single-band peak-fitting analysis of hydroxyl radical nucleic acid footprint autoradiograms for the quantitative analysis of transitions.

Hydroxyl radical footprinting can probe the solvent accessibility of the ribose moiety of the individual nucleotides of DNA and RNA. Semi-automated analytical tools are presented for the quantitative analyses of nucleic acid footprint transitions in which processes such as folding or ligand binding are followed as a function of time or ligand concentration. Efficient quantitation of the intensities of the electrophoretic bands comprising the footprinting reaction products is achieved by fitting a series of Lorentzian curves to line profiles obtained from gels utilizing sequentially relaxed constraints consistent with electrophoretic mobility. An automated process of data 'standardization' has been developed that corrects for differences in the loading amounts in the electrophoresis. This process enhances the accuracy of the derived transitions and makes generating them easier. Together with visualization of the processed footprinting in false-color two-dimensional maps, DNA and RNA footprinting data can be accurately, precisely and efficiently processed allowing transitions to be objectively and comprehensively analyzed. The utility of this new analysis approach is illustrated by its application to the ion-meditated folding of a large RNA molecule.

Autoradiography↗
PubMed2001

Isolation and HPLC quantitative analysis of flavonoid glycosides from Brazilian beverages (Maytenus ilicifolia and M. aquifolium).

Aqueous infusions of Brazilian Maytenus leaves are used as beverages, foodstuffs, and phytomedicines. Previously, we isolated two new flavonoid tetrasaccharides from the infusion of Maytenus aquifolium leaves that showed antiulcer activity. In this investigation a new flavonoid tetrasaccharide, kaempferol-3-O-alpha-L-rhamnopyranosyl (1-->6)-O-[alpha-L-arabinopyranosyl (1-->3)-O-alpha-L-rhamnopyranosyl (1-->2)]-O-beta-D-galactopyranoside (3), was isolated, together with kaempferol tri- and disaccharides and quercetin trisaccharides from the aqueous infusion of Maytenus ilicifolia leaves. All structures were elucidated by ES-MS and NMR spectroscopic methods. The quantitative analysis of the flavonoid glycosides from Maytenus ilicifolia and M. aquifolium has been performed by HPLC.

Beverages↗
PubMed1999

Videostrobokymography: a new method for the quantitative analysis of vocal fold vibration.

OBJECTIVES: To develop a new analysis method for the quantitative assessment of vibration of the vocal folds, using conventional videostroboscopic image data. METHODS: We used prerecorded videostroboscopic images to evaluate quantitatively the vibration of the vocal folds. Successive images were converted as digital images by means of an image-grabbing board, processed for analysis, and reconstructed as kymograms by rearranging the same lines of all processed images along the time axis. RESULTS: We developed a new technique for evaluating the vibration of the vocal folds. The vibrations of multiple vocal fold regions were easily and objectively evaluated by this technique. The objective parameters, such as open quotient and asymmetry index, could be obtained easily using this technique. CONCLUSIONS: Videostrobokymography demonstrated objectively the vibrations of several vocal fold regions at the same time. This technique has the potential to be a new tool to analyze and monitor the pathological changes and treatment results of vocal fold movement in a more refined quantitative fashion, using videostroboscopic images.

Electrophysiology↗
PubMed2007

Matrix-matched quantitative analysis of trace-elements in calcium carbonate shells by laser-ablation ICP-MS: application to the determination of daily scale profiles in scallop shell (Pecten maximus).

A micro-scale method has been developed for analysis of trace-element concentration profiles in the calcium carbonate shell of the Great Scallop (Pecten maximus). UV laser ablation at 266-nm coupled with ICP-MS detection was used to analyse daily calcite striae of shell samples to obtain high temporal resolution of trace element incorporation. Analysis of scallop shells was carefully examined to determine the quality of calcium carbonate ablation and calibration. An accurate external calibration method based on matrix matching was developed. Twelve sodium-free enriched calcium carbonate standards containing up to twenty-four elements were prepared, by co-precipitation with aqueous ammonia and NH(4)HCO(3), and subsequently back-calibrated in the laboratory. These CaCO(3) standards were found to be homogenous and their use enabled sensitive quantitative analysis (detection limits of a few ng g(-1)) over a wide range of concentrations (0.1 to 500 microg g(-1)). Use of these CaCO(3) standards was also evaluated by analysis of three calcium-rich certified reference materials. Because calibration was consistent with the certified results, this analytical method is a sensitive tool for analysis of environmental calcium carbonate matrices. Repeated analysis of scallop shell samples collected simultaneously at the same location showed that the trace elements are homogeneously distributed along a stria. The reliability of such in-situ records of biogenic calcium carbonate (scallop shells) is apparent from the inter-individual and inter-annual reproducibility of the trace element profiles.

Animals↗
PubMed1993

Quantitative analysis of cefradine by liquid chromatography on poly(styrene-divinylbenzene).

A method is described for isocratic analysis of cefradine by liquid chromatography on a poly(styrene-divinylbenzene) column (PLRP-S, 250 x 4.6 mm i.d.) at 50 degrees C. Cefradine is separated from its related substances using a mobile phase of acetonitrile-0.02 M sodium 1-octanesulphonate-0.2 M phosphoric acid-water (14.5:10:5:up to 100, v/v/v/v). The flow rate was 1.0 ml min-1 and UV-detection was performed at 254 nm. The method was employed for the quantitative analysis of reference substances, bulk samples and pharmaceutical dosage forms.

Acetonitriles↗
PubMed2004

Characterization and quantitative analysis of DNA adducts formed from lower chlorinated PCB-derived quinones.

Polychlorinated biphenyls are wide pollutants readily detected in environmental and human specimens. DNA adduction occurs through the corresponding quinones. Polychlorinated biphenyls are first metabolized to arene oxides, which can be further oxidized to dihydroxy metabolites by microsomal cytochrome p450s. The catechol and hydroquinone products are further oxidized by peroxidases to quinones, which are electrophilic and capable of reacting with DNA to form adducts. DNA adduction is initiated by Michael addition preferentially to guanosine followed by stabilization through enolization. Another nucleophilic attack forms a five-membered ring, which aromatizes by dehydration to form the final adduct. This report describes the characterization and quantitative study of DNA adducts formed from lower chlorinated PCB-derived quinones. Quantitative study by HPLC/ESI-MS/MS and (32)P-postlabeling-HPLC gave the adduct levels in the range of 3-1200 adducts per 10(8) nucleotides. These results demonstrate that increasing chlorine substitution is associated with lower yields of DNA adduct. Although (32)P-postlabeling is more sensitive than HPLC/ESI-MS/MS for the quantitative analysis of DNA adducts, modification levels were severely underestimated by the (32)P-postlabeling assay as compared to the HPLC/ESI-MS/MS assay.

Chromatography, High Pressure Liquid↗
PubMed2005

Quantitative analysis of lymphangiogenic markers for predicting metastasis of human gastric carcinoma to lymph nodes.

The spread of tumor cells to regional lymph nodes is an early event of gastric cancer metastasis. In our study, we assessed the expression of lymphangiogenic factors and lymphatic endothelial markers in gastric carcinoma tissues and compared expression levels with the status of lymph node metastasis. We also examined the correlation between lymphatic vessel density (LVD) in primary tumors and lymph node metastasis. Paired biopsy samples (tumor and corresponding normal mucosa) of gastric tissue were obtained from 39 patients with gastric carcinoma. The expression of VEGF-C, VEGF-D, VEGFR-3 and podoplanin mRNAs was assessed by real-time quantitative PCR. The expression of VEGF-C (but not of VEGF-D) was significantly greater in patients with lymph node metastasis than in those without metastasis. The expression of lymphatic endothelial markers VEGFR-3 and podoplanin was also significantly greater in the node-positive group. LVD, as assessed by immunohistochemistry for podoplanin, was correlated with lymph node metastasis. These results indicate that quantitative analysis of lymphangiogenic markers in gastric biopsy specimens may be useful in predicting metastasis of gastric cancer to regional lymph nodes.

Biomarkers, Tumor↗
PubMed1985

[Quantitative analysis of auto-oxidation products of cholesterol in food of animal origin].

After extraction with methylene chloride, isolation of the unsaponifiable lipid fraction and enrichment by two-step column chromatography, the oxycholesterols were gas chromatographically separated in the form of their trimethylsilyl ethers on a thin film capillary and identified by mass spectrometry. The three major products of cholesterol autoxidation were cholest-5-en-3 beta, 7 alpha-diol(I) its 7 beta-epimer(II) and 5,6-epoxy-cholestan-3 beta-ol(III). In addition, traces of cholestan-3 beta, 5 alpha, 6 beta-triol and cholest-5-en-3 beta,25-diol were detected in some samples. Quantitative analysis was performed with cholest-5-en-3 beta,19-diol as internal standard. The highest concentrations of I-III were found in spray dried egg powders (total amount 15-60 micrograms/g). Parmesan cheese, butter oil and sausages contained significantly lower levels of I-III (total amount 0.1-2.6 micrograms/g). The concentrations of I-III increased strongly when butter oil and beef tallow were heated at 170 degrees C in the presence of air for a longer period.

Animals↗
PubMed2004

Quantitative analysis on economic contribution of community health service in China.

In China, the implementation of community health service shows that the prevention is an essential and important part of our national health system and is helpful to decrease the medical expenditure gradually. According to the data from Health Statistic Information Center of Ministry of Health in China, we calculated that the total health expenditure of China would be decreased 8000.0 million yuan only in 2001, among which, 1188.3 million, 1953.9 million and 4833.0 million yuan were respectively saved for the government budget, the society and resident if implementing the policy of community health service powerfully. And every outpatient can save 15.46 yuan per time. By the quantitative analysis on the economic contribution of community health service, it can be proved that a great economic benefit could be gotten from the implementation of community health service.

China↗
PubMed1986

Visualization of moving fluid: quantitative analysis of blood flow velocity using MR imaging.

A new method for the measurement of blood flow using magnetic resonance imaging has been developed. The flow velocities are calculated from the distances that the fluid has moved. The distances are directly visualized by a new pulse sequence. In a phantom study, the measured flow rates showed very good correlation with actual flow rates of up to 20 l/min (3 m/sec). In a volunteer study, pulsatile flow velocities of a large artery were measured with electrocardiographic gating. The flow pattern of a cardiac cycle at the abdominal aorta is similar to that revealed by other methods of measurement, such as Doppler ultrasound. This method allows reasonably accurate quantitative analysis of blood flow in the large arteries.

Blood Flow Velocity↗
PubMed1988

Human gut neuroanatomy: methodology for a quantitative analysis of nerve elements and neurotransmitter diversity in the human "enteric nervous system".

After a few decad of neglect, the "enteric nervous system" has recently regained the attention of investigators. Indeed, various studies, such as those which led to the isolation from the gut of a number of neuropeptides, subsequently demonstrated throughout the nervous system, have prompted major advancements of modern neuroscience. In spite of a wealth of animal investigations and a number of human studies, however, available information concerning the human "enteric nervous system" is comparatively sparse. In the opinion that such lack of information was largely due to unavailability of appropriate techniques, we have initiated and developed a new comprehensive methodology. This way, a quantitative analysis was made possible of both nerve structure and transmitter status, point-to-point along the gut, as well as within the various, functionally heterogeneous components of the gastrointestinal wall itself. After a general introduction, the present review is intended to summarize such methodology, with the addition of a few illustrative examples of application and a practically-oriented guideline to its use, in the form of technical appendix.

Autonomic Nervous System↗
PubMed2003

A quantitative analysis of intron effects on mammalian gene expression.

In higher eukaryotes, intron-containing and intronless versions of otherwise identical genes can exhibit dramatically different expression profiles. Introns and the act of their removal by the spliceosome can affect gene expression at many different levels, including transcription, polyadenylation, mRNA export, translational efficiency, and the rate of mRNA decay. However, the extent to which each of these steps contributes to the overall effect of any one intron on gene expression has not been rigorously tested. Here we report construction and initial characterization of a luciferase-based reporter system for monitoring the effects of individual introns and their position within the gene on protein expression in mammalian cells. Quantitative analysis of constructs containing human TPI intron 6 at two different positions within the Renilla luciferase open reading frame revealed that this intron acts primarily to enhance mRNA accumulation. Spliced mRNAs also exhibited higher translational yields than did intronless transcripts. However, nucleocytoplasmic mRNA distribution and mRNA stability were largely unaffected. These findings were extended to two other introns in a TCR-beta minigene.

Animals↗
PubMed1983

Computer-based quantitative analysis of gallium-67 uptake in normal and diseased lungs.

To study the 67Ga lung uptake as an index of inflammatory activity, we developed a computer-based method to process the data obtained from the 67Ga scan. Background radioactivity below the kidneys was subtracted from counts in all areas and given a score of 0; the maximal liver uptake was scored as 16. Radioactivity over six lung fields was scored by the computer between 0 and 16 and averaged to yield a mean 67Ga lung uptake index. This index of 67Ga lung accumulation correlates with histopathologic scores of inflammation in lung tissue and with bronchoalveolar lavage (BAL) levels of 67Ga radioactivity retrieval. This study reports the quantitative analysis of 67Ga lung uptake in normal subjects and patients with various pulmonary diseases. This method provides an objective index of inflammatory activity in lung tissues, and it is simple, sensitive, and discriminative.

Adult↗
PubMed1976

[The vectorcardiogram of Fallot's tetralogy in the first two years of life. Qualitative and quantitative analysis (author's transl)].

36 patients, less than two years old, affected by Fallot's tetralogy were studied by vectorcardiography. The configuration of the QRS loop in the three orthogonal planes, the voltage of the 0.10 sec spatial vector, RMSV and LMSV vectors, and their azimuth and elevation were evaluated. Such data have been correlated to arterial oxygen saturation. Qualitative analysis showed a clockwise or figure eight QRS loop on the H and F planes in the great majority of cases; and only in a counterclockwise loop on the H plane was the suspicion of an arterial oxygen saturation greater than 85% especially in cases older than two months. The terminal forces of the QRS loop on the H plane were always directed under the O point, Whereas in the valvular pulmonary stenosis, terminal forces are generally superior to the O point. Quantitative analysis demonstrated the constant increase of the RMSV and the direct relationship of the LMSV to arterial oxygen saturation, and so it was the principal parameter for evaluation of the left ventricular volume and the size of pulmonary flow and the degree of pulmonary stenosis. The relationship between the azimuth of 0.01 sec spatial vector to O2 saturation was highly significant, showing a progressive anterior development of the former, as the latter increased.

Age Factors↗
PubMed1996

[Morphological and quantitative analysis of the mechanism of balloon angioplasty. An intravascular ultrasonic study].

BACKGROUND AND OBJECTIVES: Intracoronary ultrasound allows to study in vivo the morphology of the arterial wall, the presence and composition of atheroma and the associated lumen encroachment. The objective of our study was to assess the value of intravascular ultrasound to determine the dilatation mechanism after a conventional balloon angioplasty. PATIENTS AND METHODS: Sixteen patients were examined with intravascular ultrasound before and after they had undergone percutaneous transluminal coronary angioplasty. A mechanical intravascular ultrasound system was used. Two different types of imaging catheters were used in this study: a 20 MHz, 4.8 F catheter in 5 patients and a 30 MHz, 3.5 F in 11 patients. RESULTS: Quantitative and qualitative assessments were made from the angiograms and the ultrasound images. Seven out of 16 patients had a calcified plaque, in 8 patients the plaque was fibrotic and in 1 patient soft. Rupture of the plaque was the most common dilatation pattern. Post-PTCA the cross-sectional arterial area was increased from 15.3 +/- 5.2 mm2 to 17.3 +/- 6.2 mm2, the intraluminal area was increased from 2.7 +/- 2.5 mm2 to 7.3 +/- 3.4 mm2, and the plaque area was reduced from 12.3 +/- 4.8 mm2 to 9.7 +/- 3.4 mm2. The quantitative analysis showed that the "most frequent dilatation mechanism" found was the reduction of size plaque, an increase in cross-sectional arterial area was present in only 4 patients (25%). The incidence of depth rupture of the plaque was greater in patients with a calcified plaque than in those without (NS). CONCLUSIONS: 1). Intracoronary ultrasound provides a complete description of plaque composition and geometry before and after coronary balloon angioplasty; 2) several morphologic dilatation patterns were found, and plaque tearing was the most common, and 3) increase in luminal area was most frequently due to a reduction in plaque area. Nevertheless an increase in the cross-sectional arterial area was also common, but less important.

Aged↗