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At least 397 records · Page 22Linked to original sources
PubMed2002

A quantitative analysis of geographic color variation in two Geotrupes dung beetles.

We conducted a quantitative analysis of geographic color variation in two species of dung beetles: Geotrupes auratus and G. laevistriatus. The reflectance of the dorsal surfaces was measured from 300 to 700 nm using a spectrophotometer. The reflectance curves for both beetles were bimodal; there were two distinct peaks, namely, the a peak, between 400 and 700 nm, and the beta peak at around 300 nm. A stepwise discriminant analysis indicated that geographic color variation in Geotrupes beetles was primarily characterized by a shift of the a peak. Using beetles from three locations, we compared the wavelength (nm) of the a peak (lambdamax(alpha)) and its reflectance intensity (R(a)) to investigate sex and population differences. Intraspecific geographic variation in coloration was effectively detected by discriminant analysis of spectral reflectance curves. Our results showed that G. auratus and G. laevistriatus had similar coloration within each sampling location. Our study also revealed hidden sex differences in R(a); R(a) of males were significantly higher than those of females in both species. Since the dorsal surface of the beetles shows remarkable color variation, and coloration can be assessed objectively using reflectance spectra, Geotrupes beetles may be good model organisms to investigate geographic color variation.

Animals↗
PubMed1999

[Relationship between serum fibrosis markers and fibrosis quantitative analysis of liver tissue].

OBJECTIVE: To study relation of serum fibrosis markers with quantitative analysis of liver tissue. METHODS: We studied the area of reticular fibrin, collagen fibrin and elasticity fibrin in 77 patients with chronic liver disease using color image analysis system. RESULTS: From S0 to S4, the area of three kinds of liver fibrosis were all escalate, especially collagen fibrosis. Prominent differences existed between S3 and S2, S2 and S1, S1 and S0. There was a good correlation between the serum fibrosis markers and area of collagen fibrosis of liver tissue, r = 0.70775(HA), 0.59402(CIV), 0.52593(LN), 0.52198 (hPCIII). CONCLUSIONS: Serum fibrosis markers have affirmative value to help diagnose liver fibrosis.

Adolescent↗
PubMed1975

Ordering methods in quantitative analysis of branching structures of dendritic trees.

Two different ordering methods used in quantitative analysis of dendritic trees are compared with respect to the chief objective of doing the ordering, viz. grouping together those segments of a branching pattern which have similar characteristics. After describing the different properties of these two ordering methods (i.e., Strahler method and centrifugal method), criteria are given for selecting one or the other of the two methods.

Dendrites↗
PubMed2005

[Study on temperature correctional models of quantitative analysis with near infrared spectroscopy].

Effect of enviroment temperature on near infrared spectroscopic quantitative analysis was studied. The temperature correction model was calibrated with 45 wheat samples at different environment temperaturs and with the temperature as an external variable. The constant temperature model was calibated with 45 wheat samples at the same temperature. The predicted results of two models for the protein contents of wheat samples at different temperatures were compared. The results showed that the mean standard error of prediction (SEP) of the temperature correction model was 0.333, but the SEP of constant temperature (22 degrees C) model increased as the temperature difference enlarged, and the SEP is up to 0.602 when using this model at 4 degrees C. It was suggested that the temperature correctional model improves the analysis precision.

Algorithms↗
PubMed1992

Lactic acidosis, ketoacidosis, and energy turnover: "figure" you made the correct diagnosis only when you have "counted" on it--quantitative analysis based on principles of metabolism.

Three cases are presented to illustrate that quantitative analysis based on physiologic principles can help resolve certain controversies in clinical medicine. For example, in case 1, a patient with severe hypoxia, the rate of production of lactic acid is so high that only restoration of delivery of oxygen is rational therapy. If the degree of hypoxia exceeds 5.6% of demand, dichloroacetate will not lessen the degree of acidosis. Further, even when delivery of oxygen is returned to normal, the rate of fall in lactate and rise in bicarbonate in plasma will be relatively slow. In case 2, a patient with diabetic ketoacidosis, our discussion stresses that the rate of production of ketoacids is not that rapid and that the degree of ketoacidosis is influenced to a major degree by decreasing the rate of oxidation of ketoacids in brain and kidneys. Case 3, a patient with severe hyperglycemia, illustrates that insulin will only promote the oxidation of glucose at a rapid rate once the levels of fatty acids and ketoacids decline to low levels. Accelerated transport of glucose by insulin is only a permissive action for the oxidation of glucose.

Acidosis, Lactic↗
PubMed1992

Quantitative analysis of regional wall thickening by transesophageal echocardiography.

To develop a method for quantitative analysis of regional left ventricular function from transesophageal two-dimensional echocardiograms, we conducted studies 10 and 20 minutes after induction of anesthesia in 16 patients with normal hearts who were undergoing minor orthopedic operations. Wall thickening was measured with the centerwall method along 100 chords drawn perpendicular to a line constructed around the center of the ventricular wall, midway between the endocardial and epicardial contours. Thickening, either normalized by the length of the end-diastolic perimeter or expressed as a percentage of the end-diastolic wall thickness at each chord, was compared with measurements of endocardial motion. Wall motion was relatively diminished in the anteroseptal region and enhanced on the contralateral wall, but wall thickening was homogeneous throughout the contour. Normalized wall thickening was significantly less variable (standard deviation/mean, 0.47 +/- 0.13) in the normal population than were either percent wall thickening (0.53 +/- 0.012) or wall motion (0.51 +/- 0.09) (p less than 0.005 for both comparisons). There was no significant change in regional or global function between 10 minutes and 20 minutes after the induction of anesthesia. In summary, normalized wall thickening as a parameter of regional left ventricular function is more homogeneous and less variable in subjects with normal hearts than is endocardial motion because wall thickening measurements are not subject to cardiac translocation artifacts. This low variability suggests that normalized wall thickening measured by the centerwall method may prove particularly useful for intraoperative and postoperative monitoring of regional left ventricular function by transesophageal echocardiography in patients undergoing both cardiac and noncardiac surgical procedures.

Adult↗
PubMed1989

Quantitative analysis of retinal glycerolipid molecular species acetylated by acetolysis.

A method for the quantitative analysis of molecular species of 1,2-diacylglycerol acetates (1,2-DGAC) containing polyunsaturated fatty acids is described. Phosphatidylethanolamine (PE) isolated from frog retina was used to test the method. PE was converted to 1,2-DGAC by acetolysis. The molecular species of the 1,2-DGAC were resolved by reverse-phase high performance liquid chromatography (HPLC), detected by UV absorption spectroscopy at 210 nm, and identified by gas-liquid chromatography (GLC) of the fatty acid methyl esters (FAME). Molar response curves were generated for each DGAC molecular species that eluted as a single entity from HPLC by determining the moles of fatty acids in the molecular species collected and the response (peak area unit) of the UV detector. Each molecular species response curve was linear from about 10 pmoles to 4-8 nmoles, allowing the slope of each curve to be used as a molar absorptivity. This method provides a means for quantification of most of the molecular species of all glycerolipid classes.

Acetylation↗
PubMed1988

Quantitative analysis of integrated Ed alpha gene expression in C57BL/6 transgenic mice.

We performed quantitative analysis of Ed alpha gene expression in the transgenic mice, created by microinjecting cloned Ed alpha gene fragments into C57BL/6 fertilized eggs. DNA dot-blot analysis revealed that Ed alpha gene-introduced transgenic mice (B6Ed alpha transgenic mice) contain 20 copies per cell of the Ed alpha gene in their genome. RNA dot-blot analysis revealed that the amount of Ed alpha mRNAs in B6Ed alpha transgenic spleen cells is 20-40-fold higher than those in normal BALB/c or (BALB x C57BL/6)F1 (CBF1) spleen cells. However, the amount of Ed alpha molecules expressed on B6Ed alpha transgenic spleen cells was similar to that expressed on normal BALB/c of CBF1 spleen cells on a gene-dose basis. The amount of endogenous Ed alpha mRNA in the B6Ed alpha transgenic spleen cells was almost equal to that of normal B6 spleen cells. Since the cell surface I-E molecule is formed by non-covalent association of E alpha and E beta chain, these results suggest that, in spite of the high expression of integrated Ed alpha gene in the cytoplasm of B6Ed alpha transgenic mice, the amount of Ed alpha gene expression on the cell surface is limited by the amount of endogenous Eb beta gene products.

Animals↗
PubMedDate not supplied

[Quantitative analysis of nucleolar organizer regions in nevi and melanomas].

The results of a quantitative analysis of nucleolar organizer regions (NORs) in a group of 45 nevi and 45 melanoma are presented. Mean value of nucleolar organizer regions in nevi was 1.29 and the standard error 0.088. Melanoma had mean value of 3.90 with a standard error of 1.542. Student's t test revealed a statistically significant difference between these two groups of benign and malignant melanocytic lesions of skin (P < 0.001), with regard to the number of NORs. In view of these results and those from the literature, the diagnostic value of the number of NORs in distinguishing benign from malignant melanocytic lesions of skin has been confirmed.

Diagnosis, Differential↗
PubMed1994

The quantitative analysis of mammographic densities.

Quantitative classification of mammographic parenchyma based on radiological assessment has been shown to provide one of the strongest estimates of the risk of developing breast cancer. Existing classification schemes, however, are limited by coarse category scales. In addition, subjectivity can lead to sizeable interobserver and intraobserver variations. Here, we propose an interactive thresholding technique applied to digitized film-screen mammograms, which assesses the proportion of the mammographic image representing radiographically dense tissue. Observers viewed images on a CRT display and selected grey-level thresholds from which the breast and regions of dense tissue in the breast were identified. The proportion of radiographic density was then calculated from the image histogram. The technique was evaluated for the mammograms of 30 women and is well correlated (R > 0.91, Spearman coefficient) with a six-category subjective classification of radiographic density by radiologists. The technique was found to be very reliable with an intraclass correlation coefficient between observers typically R > 0.9. This technique may have a role in routine mammographic analysis for the purpose of assessing risk categories and as a tool in studies of the etiology of breast cancer, in particular for monitoring changes in breast parenchyma during potential preventive interventions.

Absorptiometry, Photon↗
PubMed1983

The formation and maturation of synapses in the visual cortex of the rat. II. Quantitative analysis.

We have examined quantitatively the formation and maturation of synapses in the visual cortex of the rat. The density of the total number of synapses (synapses per 100 micron2 neuropil) as well as the densities of Gray's type I and type II contacts were estimated from photographic montages of coronal strips of visual cortex from rats of various postnatal ages. Histograms of synaptic density as a function of depth were prepared, and the mean values of the postsynaptic density length and vesicle number per terminal were estimated for the two synapse types at each age examined. During the first few days of life, synapses were concentrated in the subplate region. By the latter part of the second postnatal week they were present throughout the cortex and an adult-like distribution, in which the highest densities were present in the superficial layers, was achieved by day 14. The postsynaptic density length of the type I synapses remained relatively unchanged during development but that of the type II synapses was more variable. Specifically, it was significantly longer during the second and third postnatal weeks compared to earlier ages and to adult values. The mean number of vesicles per terminal for the two synapse types increased with age until day 28. Subsequently, it only increased slightly between days 28 and 90 for the type I synapses but decreased significantly for the type II synaptic contacts. At all ages examined, type I synapses formed the majority of synaptic contacts. The developmental pattern appeared to differ for the two synapse types. The density of type I synapses increased continuously during the first three weeks and achieved a mean value close to that of adult animals by day 20. In contrast, the density of type II synapses did not increase significantly until day 6, increased dramatically in the second and third postnatal weeks, and then declined markedly between days 20 and 90. The observed decrease in the density of type II synaptic contacts is a clear example of synapse elimination in the visual cortex.

Age Factors↗
PubMed2005

Patterns of carpal deformity in scaphoid nonunion: a 3-dimensional and quantitative analysis.

PURPOSE: To clarify quantitatively the 3-dimensional deformity of the carpus in scaphoid nonunion on the basis of fracture location. METHODS: Three-dimensional computed tomography was used to examine 20 patients with scaphoid nonunion. Displacements of the distal and proximal fragments of the scaphoid, lunate, triquetrum, and capitate were visualized and quantified using a 3-dimensional image-matching technology. Cases were categorized as distal fracture (16 cases) or proximal fracture (4 cases) based on the location of the fracture line relative to the dorsal apex of the scaphoid ridge where the dorsal scapholunate interosseous ligament is attached. RESULTS: The displayed distal scaphoid fractures showed that the proximal fragment of the scaphoid, lunate, and triquetrum rotated into extension and supination. The distal fragment of the scaphoid and capitate translated dorsally without notable rotation. The deformity in proximal fractures was less remarkable than that in distal fractures. Most distal scaphoid nonunions had dorsal intercalated segment instability deformity patterns, whereas a dorsal intercalated segment instability occurred in only 1 case of a proximal fracture. CONCLUSIONS: Whether the fracture line passes distal or proximal to the dorsal apex of the scaphoid determines the subsequent carpal deformity. Dorsal translation of the distal fragment might be one of the factors in the development of degenerative change at the radial styloid.

Adolescent↗
PubMed2002

Regulation of neurotrophic peptide expression in sympathetic neurons: quantitative analysis using radioimmunoassay and real-time quantitative polymerase chain reaction.

The regulated expression of the peptide and transcript levels of the neurotrophic peptides, pituitary adenylate cyclase-activating polypeptide (PACAP), galanin and vasoactive intestinal peptide (VIP) were examined in sympathetic neurons of the rat superior cervical ganglion (SCG). Real-time quantitative PCR methods were developed to assess modulation of neuronal peptide precursor protein transcript levels following experimental paradigms of neuropeptidergic plasticity. Oligonucleotide primer, fluorogenic probe and amplification conditions were optimized for maximal assay sensitivity. Depolarization of primary cultured sympathetic neurons stimulated PACAP, galanin, and VIP peptide contents and releases with differing magnitudes and temporal profiles. The rank order of increased neuronal peptide content paralleled the augmented peptide release (VIP>galanin>PACAP). Maximal cellular PACAP and VIP levels were achieved by 72 and 96 h, respectively; galanin levels did not plateau during the treatment period. PACAP transcript elevation was rapid and transient; PACAP mRNA expression diminished at longer depolarization times, which diverged markedly from the sustained high peptide production levels. By contrast, VIP and galanin mRNAs reached maximal levels at later times, and appeared to correlate more closely with peptide production. We previously described multiple proPACAP mRNA variants resulting from alternative 3' untranslated region cleavage and polyadenylation. The shorter depolarization-induced PACAP transcripts exhibit longer half-lives, suggesting that the short proPACAP mRNA variant may function to impart PACAP translational efficiency and sustain PACAP peptide production.

Animals↗
PubMed2005

Dornase alfa reduces air trapping in children with mild cystic fibrosis lung disease: a quantitative analysis.

PURPOSES: To evaluate quantitative air trapping measurements in children with mild cystic fibrosis (CF) lung disease during a 1-year, double-blind, placebo-controlled, recombinant human deoxyribonuclease (rhDNase) [dornase alfa] intervention trial and compare results from quantitative air trapping with those from spirometry or visually scored high-resolution CT (HRCT) scans of the chest. MATERIALS AND METHODS: Twenty-five children with CF randomized to either daily rhDNase or placebo aerosol were evaluated at baseline, and at 3 months and 12 months by spirometer-triggered HRCT and spirometry. Outcome variables were percentage of predicted FVC, FEV1, and forced expiratory flow, midexpiratory phase (FEF(25-75%)); total and subcomponent visual HRCT scores; and quantitative air trapping measurements derived from chest HRCT images. RESULTS: At baseline, there were no statistical differences between groups in any of the variables used as an outcome. After 3 months of treatment, both groups had improvements in percentage of predicted FEV1 and FEF(25-75%), and total HRCT visual scores. In contrast, the rhDNase group had a 13% decrease in quantitative air trapping from baseline (severe air trapping [A3]), compared to an increase of 48% in the placebo group (p = 0.023). After 12 months, both groups had declines in percentage of predicted FVC and FEV1, but the rhDNase group retained improvements in percentage of predicted FEF(25-75%) and quantitative air trapping. The mucus plugging and total HRCT visual scores were also improved in the rhDNase group after 12 months of treatment, with and without significant differences between groups (p = 0.026 and p = 0.676). Quantitative air trapping (A3) remained improved in the rhDNase group (- 15.4%) and worsened in the placebo group (+61.3%) with nearly significant differences noted between groups (p = 0.053) after 12 months of treatment. CONCLUSIONS: Quantitative air trapping is a more consistent sensitive outcome measure than either spirometry or total HRCT scores, and can discriminate differences in treatment effects in children with minimal CF lung disease.

Air↗
PubMed1998

NeuroSPECT findings in patients with posttraumatic anosmia: a quantitative analysis.

OBJECTIVE: To investigate quantitative neuroSPECT findings, particularly from orbital frontal cortex, in patients rendered totally anosmic from head injury. SETTING: Veterans Administration (VA) Medical Center. SUBJECTS: Eighteen patients with head injury resulting in severe anosmia and five normal controls. All 18 patients had sustained their head injuries at least 5 years prior to involvement in the study. MEASURES: Quantitative neuroSPECT (count density) from sagittal regions of interest (ROIs) ranging circumferentially from orbital frontal cortex to occipital pole. RESULTS: Quantitative evaluation of neuroSPECT findings for anosmic patients as a group showed substantial orbital frontal hypoperfusion compared with controls, with 67% of individual anosmic patients showing orbital frontal hypoperfusion at a level two or more standard deviations below that of the worst control subject. By contrast, there were no between-group differences for five other ROIs (inferior frontal pole, superior frontal pole, posterior superior frontal lobe, the parasagittal region, and occipital pole), and individual abnormalities were infrequent in these areas. In addition, orbital frontal count was significantly correlated with ratings of outcome, the only ROI to have such a relationship. CONCLUSIONS: Findings strongly suggest that posttraumatic anosmia and the neuropsychological deficits typically associated with posttraumatic anosmia are closely and specifically associated with hypoperfusion in orbital frontal cortex. The results also underscore the importance of posttraumatic anosmia as a clinical sign of orbital frontal damage, which is particularly important in patients with mild head injury who have normal computed tomography and magnetic resonance imaging scans.

Adult↗
PubMed2006

Semi-quantitative analysis of Streptococcus pneumoniae urinary antigen: kinetics of antigen titers and severity of diseases.

Detection of urinary antigen by a rapid immunochromatographic membrane test (Binax NOW) was widely accepted as a powerful tool for diagnosis of Streptococcus pneumoniae pneumonia. This is a qualitative kit, so the value of quantitative analysis of urinary antigen, especially correlation of antigen titers and severity of diseases, remained to be determined. We examined semi-quantitative antigen titer in urines collected from urinary antigen-proven S. pneumoniae pneumonia on admission, and analyzed the kinetics of antigen titer and its relation to severity of diseases. After serial 2-fold dilution of urine, the highest dilution for positive results was determined, and this was designated as maximum dilution factor (MDF). MDFs varied from 1 to 4096 in 29 patients examined (mean MDF, 317.8). Importantly, severe cases of S. pneumoniae pneumonia were higher values of MDFs (mean MDF: 760.5) than those of non-severe cases (mean MDF: 5.4). The patients with high MDFs (> or = 64) demonstrated higher values of LDH, CRP and lower values of WBC and PaO2 compared to those of low MDFs group (< or = 32). There was no clear correlation between CRP values and antigen titers, and conversely the majority of severe cases showed relatively weak CRP responses, despite high levels of bacterial antigen. Kinetic analysis of urinary and serum antigen titers in 4 cases of S. pneumoniae pneumonia exhibited consistently higher values of antigen titers in urine than those in serum. The half lives of urinary and serum antigen titers were calculated to be 1.0-3.4 and 1.1-2.3 weeks, respectively. These data suggest that quantitative analysis of urinary antigen may be a useful indicator for severity of disease and course of S. pneumoniae pneumonia. Our results demonstrate an application for S. pneumoniae antigen titer determination in urine and serum, which may be crucial not only for diagnostic measures, but also may provide a better understanding of the pathogenesis of S. pneumoniae infection.

Antigens, Bacterial↗