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PubMed1990

A quantitative analysis of the liver following ligation of the common bile duct.

A quantitative analysis of the liver was performed at intervals of 24, 48, 72 and 96 h and 7, 21 and 50 days following total biliary obstruction (TBO) in the Sprague-Dawley rat. During this period, the liver weight increased from 7.72 +/- 0.51 g (mean +/- SEM) in controls to 24.57 +/- 1.66 g (p less than 0.0005) at 50 days. There was a concomitant reduction in the volume proportion of the liver occupied by liver cells, from 71.37 +/- 1.36% to 21.54 +/- 3.27% (p less than 0.0005), but there were increases in the volume proportions of biliary epithelial cells (BEC) from 0.14 +/- 0.02% to 16.39 +/- 1.12% (p less than 0.0005), of other cell and tissue types from 5.50 +/- 4.89% to 30.73 +/- 2.42% (p less than 0.0005) and of vascular and biliary channel spaces from 22.99 +/- 1.17% to 31.35 +/- 0.87% (p less than 0.0025). In control animals, the liver cell and BEC volume was estimated to be 6240 +/- 360 microns 3 and 100 +/- 10 microns 3, respectively. Following TBO, the liver cell volume was significantly greater than control only from 48-96 h, whereas the BEC increased significantly in volume from 24 to 72 h and then remained approximately 6 times the control value until the end of the period of study. Contrary to the histological appearance and decrease observed in volume proportion, the total liver cell population did not significantly differ from the control value of 8.83 x 10(8) +/- 0.80 x 10(8) cells, other than at 21 days when it increased to 14.90 x 10(8) +/- 1.04 x 10(8) cells (p less than 0.05). When expressed as the number of liver cells/100 g b.wt., an increase from the control value of 4.37 x 10(8) +/- 0.32 x 10(8) cells was observed only at 7 (5.66 x 10(8) +/- 0.42 x 10(8) cells; p less than 0.05) and 21 days (6.94 x 10(8) +/- 0.48 x 10(8) cells; p less than 0.05). This maintenance of liver cell population, following biliary obstruction, at or above the control values matches the clinical observation of preserved liver cell function. The total BEC population in control livers was 1.11 x 10(8) +/- 0.20 x 10(8) cells. A significant increase in this population was observed at 7 days (3.82 x 10(8) +/- 0.62 x 10(8) cells; p less than 0.05) with further increases to 57.90 x 10(8) +/- 6.42 x 10(8) cells (p less than 0.05) at 50 days, 52 times the control value. When expressed as cells/100 g b.wt., similar changes were observed. The results reported here indicate the importance of taking into account the change in the entire organ size and total mass of the cells in question when assessing alterations in their number.

Animals↗
PubMed1976

Quantitative analysis of the proliferative activity induced in murine thymocytes by concanavalin A.

A quantitative analysis of the proliferative response induced in murine thymocytes by concanavalin A (Con A) is described. Exogenous 3H-thymidine labels 35 to 40% of the newly incorporated TMP residues under optimal conditions. The density label 5-bromo-2-deoxuridine (BrUdR) does not affect DNA metabolism in this system. With this nucleoside, it is shown that newly synthesized DNA is the result of semi-conservative replication, not repair. Double labeling of DNA provides a monitor for cells traversing the cell cycle (S phase to subsequent S phase). The average cycle time is 12.5 hr, and the shortest cell cycle time is 10 hr. The growing fraction of active cells is about two-thirds. The data show that different subpopulations of thymocytes begin proliferating after various times in culture. Once effectively stimulated by Con A, some of the cells can traverse the cell cycle at least twice more after the mitogen is removed.

Animals↗
PubMed1991

Quantitative analysis of radiophosphate uptakes in asymptomatic porous-coated hip endoprostheses.

A quantitative analysis of the uptake of radiophosphate adjacent to the femoral component of a porous-coated cementless prosthesis was undertaken in asymptomatic patients in order to establish normal temporal changes. The group consisted of 55 patients with 62 arthroplasties of 1.6-49-mo duration. Ratios of the stem, stem tip, greater trochanter, lesser trochanter and calcar, and normal femur to the reference sacroiliac joint were obtained, as well as tip-to-stem, and stem-to-normal femur in unilateral arthroplasties. The ratios remained stable at 12 months and beyond, except for the tip and lesser trochanter. Tip-to-stem and tip-to-sacroiliac joint ratios decreased by 24% and 33%, respectively, between 12 and 49 mo. There was also a decrease in the relative uptakes at the lesser trochanter and calcar in the same time interval. Evidence is given that different designs of prostheses may not have the same normal temporal uptakes of radiophosphate.

Adult↗
PubMed1984

[A new model for the quantitative analysis of left ventricular regional function].

A computer-assisted model for quantitative analysis of left ventricular segmental wall motion is presented. In contrast to standard rectangular and radial chord methods, no coordinate and reference system is used. Normal wall motion of 5 ventricular segments in the RAO projection was evaluated in 20 patients with normal ventriculograms. Segmental wall motion abnormalities after myocardial infarction were then analyzed by the computer-assisted method in 60 patients and the results compared with the visual assessment of an experienced cardiologist as standard reference. 96% of all segments with normal motion, 95% of all hypokinetic segments and 100% of all dyskinetic segments were correctly identified by computer analysis. Akinesia, however, was detected only in 25% of all cases and misinterpreted chiefly as hypokinesia. Further refinement of the software should improve detection of akinesia and classification of hypokinesia.

Adult↗
PubMed1990

A method for the quantitative analysis of molecular species of alkylacylglycerol and diacylglycerol.

We describe a method for the quantitative analysis of molecular species of diacylglycerol and alkylacylglycerol as their diradylglycerobenzoate derivatives. Synthetic internal standards were used to provide quantitative determinations of the low levels of diacylglycerol and alkylacylglycerol and their individual molecular species in cultured cells. Diradylglycerols were isolated by thin-layer chromatography (TLC), converted to their benzoate derivatives and separated into subclasses by TLC. The molecular species of each subclass were analyzed by reversed-phase high performance liquid chromatography. Thirty-six species of diglyceride-type molecules were identified in Madin-Darby canine kidney cells. These cells were shown to contain 7.88 nmoles of diacylglycerol and 3.97 nmoles of alkylacylglycerol per mumole of phospholipid. Both subclasses contain predominantly monoenoic and saturated species. This technique should be valuable for studies examining the origin and metabolism of these important intracellular mediators.

Animals↗
PubMed2004

Quantitative analysis of pulmonary perfusion using time-resolved parallel 3D MRI - initial results.

PURPOSE: To assess the use of time-resolved parallel 3D MRI for a quantitative analysis of pulmonary perfusion in patients with cardiopulmonary disease. MATERIALS AND METHODS: Eight patients with pulmonary embolism or pulmonary hypertension were examined with a time-resolved 3D gradient echo pulse sequence with parallel imaging techniques (FLASH 3D, TE/TR: 0.8/1.9 ms; flip angle: 40 degrees; GRAPPA). A quantitative perfusion analysis based on indicator dilution theory was performed using a dedicated software. RESULTS: Patients with pulmonary embolism or chronic thromboembolic pulmonary hypertension revealed characteristic wedge-shaped perfusion defects at perfusion MRI. They were characterized by a decreased pulmonary blood flow (PBF) and pulmonary blood volume (PBV) and increased mean transit time (MTT). Patients with primary pulmonary hypertension or Eisenmenger syndrome showed a more homogeneous perfusion pattern. The mean MTT of all patients was 3.3 - 4.7 s. The mean PBF and PBV showed a broader interindividual variation (PBF: 104 - 322 ml/100 ml/min; PBV: 8 - 21 ml/100 ml). CONCLUSION: Time-resolved parallel 3D MRI allows at least a semi-quantitative assessment of lung perfusion. Future studies will have to assess the clinical value of this quantitative information for the diagnosis and management of cardiopulmonary disease.

Acute Disease↗
PubMed1977

Quantitative analysis of tricyclic antidepressants in serum from psychiatric patients.

A method for the quantitative analysis of tricyclic antidepressants in the serum of psychiatric patients is described. The method can be used for determining amitriptyline, nortriptyline, imipramine, demethyllimipramine, clomipramine, demethylclomipramine, trimipramine and protriptyline. The method consists in a series of extraction steps followed by gas chromatography with flame-ionization detector. The drugs are determined in their native state. The internal standard method is used for the quantitation.

Antidepressive Agents, Tricyclic↗
PubMed1994

Quantitative analysis of macromolecular conformational changes using agarose gel electrophoresis: application to chromatin folding.

Quantitative analysis of chromatin electrophoretic mobility (mu) in agarose gels provides a measure of three structural parameters: average surface electrical charge density, which is proportional to the gel-free mu (mu 0), effective radius (Re), and particle deformability [Fletcher, T. M., Krishnan, U., Serwer, P., & Hansen, J. C. (1994) Biochemistry 33, 2226-2233]. To determine whether the intramolecular conformational changes associated with salt-dependent chromatin folding influence these electrophoretic parameters, defined oligonucleosomes were reconstituted from monodisperse tandemly repeated 5S DNA and varying amounts of histone octamers. These oligonucleosomes were subjected to both quantitative agarose gel electrophoresis and analytical velocity ultracentrifugation in buffers containing 0-2 mM MgCl2. Ionic conditions that caused a 40% increase in the oligonucleosome sedimentation coefficient (s20,w) also caused both a 30% decrease in Re and a 60% decrease in the magnitude of the mu 0. Furthermore, the Mg(2+)-dependent changes in s20,w, Re, and mu 0 each exhibited the same nonlinear dependence on the degree of nucleosome saturation of the DNA. These data demonstrate that quantitative agarose gel electrophoresis can be used to detect and characterize the process of chromatin folding. In addition, they suggest that this approach can be used for characterization of the conformational dynamics of many other types of macromolecular assemblies, including those systems that are not yet amenable for study by more traditional quantitative biophysical techniques.

Animals↗
PubMed1996

Qualitative and quantitative analysis of AgNOR proteins in chemically induced rat liver carcinogenesis.

A qualitative and quantitative analysis of silver-stained nuclear organizer regions (AgNOR) proteins was performed during hepatocarcinogenesis induced in rats initiated by diethylnitrosamine (DENA) using the resistant-hepatocyte model. Nuclear proteins from control hepatocytes, hyperplastic nodules, and hepatocellular carcinomas (HCC) separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were transferred to nitrocellulose membranes and specifically silver-stained for AgNOR proteins. No difference was observed in the distribution pattern of the silver-stained bands among control, hyperplastic, or cancer cells. The same was true if human cirrhosis and HCC were compared. The evaluation of individual AgNOR protein amounts by computerized densitometric analysis showed that 1) the integrated optical density value of the total AgNOR proteins was greatest in cancer cells, lesser in hyperplastic hepatocytes, and lowest in control hepatocytes, and 2) the amount of the two major silver-stained proteins, nucleolin (105 kd) and protein B23 (39 kd), was always a constant percentage of total AgNOR proteins. An experiment using bromodeoxyuridine incorporation showed that, during hepatocarcinogenesis, AgNOR protein quantity progressively increased and was significantly related to the increased hepatocyte labeling index. These results show that AgNOR protein distribution changes during hepatocarcinogenesis are caused neither by the synthesis of new AgNOR proteins nor by an unbalanced synthesis of individual AgNOR proteins, but to an increased synthesis of nucleolin and protein B23, which is associated with a progressive increased hepatocyte proliferation rate.

Animals↗
PubMed2004

Addressing the overlap problem in the quantitative analysis of two dimensional NMR spectra: application to (15)N relaxation measurements.

A quantitative analysis of 2D (1)H-(15)N spectra is often complicated by resonance overlap. Here a simple method is presented for resolving overlapped correlations by recording 2D projection planes from HNCO data sets. Applications are presented involving the measurement of (15)N T(1rho) relaxation rates in a high molecular weight protein, malate synthase G, and in a system that exchanges between folded and unfolded states, the drkN SH3 domain. By supplementing relaxation data recorded in the conventional way as a series of 2D (1)H-(15)N data sets with a series of a pair of projection planes the number of dynamics probes is increased significantly for both systems studied.

Algorithms↗
PubMed1980

Quantitative analysis of short term deprivation and recovery of desynchronized sleep in cats.

A quantitative analysis of desynchronized sleep (DS) deprivation (exposure to low ambient temperature) and recovery was carried out in unrestrained cats. The results show that: (1) the circadian obligate quota of DS is precisely regulated by a control mechanism paying by the 24th h the DS debt induced by up to 14 h of total DS deprivation, if recovery occurs during the rest phase of circadian photoperiodicity (CP); (2) during static rebound DS hourly duration is increased by 40 +/- 4 sec/h of total deprivation (mean and S.E.) and there is a statistically significant increase in the hourly frequency and in the duration of DS episodes, with respect to control values; (3) the hourly obligate and facultative quotas of DS amount to 409 +/- 82 and 229 +/- 140 sec/h (mean and S.D.), respectively. (4) preoptic heating during deprivation at low ambient temperature decreases the DS static rebound during recovery at control ambient temperature by an amount corresponding to the cumulative duration of DS episodes elicited by the preoptic treatment; (5) preoptic temperature decreases the more markedly the shorter the duration of exposure to low ambient temperature and regains control values the sooner the smaller the DS debt incurred during deprivation; (6) DS debt cumulation is a continuous process which develops at a steady rate during day and night, whereas DS debt payment is a discontinuous process (ultradian rhythm of DS) which develops at a variable rate depending on the DS debt and on the phase of CP.

Animals↗
PubMed1996

Aspects of the quantitative analysis of neurons in the cerebral cortex.

We address three problems concerning the quantitative analysis of nerve cell distribution in the cerebral cortex: (i) preparatory tissue deformation (shrinkage); (ii) difficulties in differentiating between small neurons and astroglia; and (iii) the bias introduced by the counting method. We found that staining with Richardson's solution led to no shrinkage in Vibratome-cut sections of aldehyde-fixed rat brains, but did result in staining of the neurons and left the glial cells unstained. This was in striking contrast to Nissl staining which introduced a linear shrinkage of 20-30% and stained all kinds of cortical cells indiscriminately. A computer-based unbiased counting method was implemented by taking advantage of the stereological procedure referred to as the 'optical disector' (Gundersen, H.J.G. (1986) Stereology of arbitrary particles, J. Microsc., 143: 3-45).

Animals↗
PubMed1995

Quantitative analysis and immunohistochemical studies on small intestinal mucosa of food-sensitive enteropathy.

Quantitative analysis and immunohistochemical studies of small intestinal mucosa were performed to investigate the mechanism of mucosal damage in 10 patients with food-sensitive enteropathy. Jejunal biopsy specimens were taken before and after treatment and after clinical relapse following a challenge test. The low villous height of untreated patients normalized after introduction of an elimination diet but declined again to subnormal level after a challenge test. Several other types of cells were significantly increased in the untreated patients in comparison to controls. These included HLA-DR+ (DR+) CD4+ cells in the lamina propria and intraepithelial CD8+ cells. Moreover, those cell patterns, such as increased DR+ CD4+ cells and CD8+ cells, normalized with treatment but regressed to pretreatment levels when the patients were challenged. These findings suggest that activated CD4+ cells in the lamina propria of the small intestinal mucosa, probably by releasing cytokines, may play an important role in contributing to mucosal damage in patients with food-sensitive enteropathy.

Animals↗
PubMed1985

Rotation of the cell nucleus in living cells: a quantitative analysis.

Nuclear rotation is observed in a variety of cell types. However, few quantitative analyses are reported and the significance of this phenomenon is still unclear. To investigate this type of nuclear movement, we performed a quantitative analysis in mouse L-929 fibroblasts, a cell line chosen since it displays a high nuclear rotational activity. Analyses were performed using time-lapse microcinematography. The relationship between nuclear rotation and other cellular phenomena such as the cell cycle and locomotion were studied. Then, we investigated the rotation in a population of sister cells to study whether it is genetically determined. Finally, we performed a qualitative analysis of nuclear rotation in different cultured cell lines. Results show that nuclear rotations preferentially occur during the phases of the cell cycle which surround mitosis.

Animals↗
PubMed2005

Quantitative analysis of camptothecin derivatives in Nothapodytes foetida using 1H-NMR method.

A quantitative analysis using (1)H-NMR has been developed for the determination of camptothecin derivatives and trigonelline in Nothapodytes foetida root, stems and leaves. In the region of delta 9.5-5.5, the signals of H-7 of camptothecin (1), H-10 of 9-methoxycamptothecin (2), H-19 of pumiloside (3) and H-2 of trigonelline (4), were well separated from each other in DMSO-d(6). The quantity of the compounds was calculated by the ratio of the intensity of each compound to the known amount of internal standard 3,4,5-trimethoxybenzaldehyde. These results were compared with the conventional HPLC method. The advantages of the method are that no reference compounds are required for calibration curves, the quantification could be directly realized on a crude extract, an overall profile of the preparation could be directly obtained, and a very significant time-gain could be achieved, in comparison to conventional HPLC methods, for instance.

Camptothecin↗
PubMed1979

[A quantitative analysis of urinary 17-KS by GC-MS (author's transl)].

A quantitative analysis of seven components of 17-KS in human urine was successfully carried out by GCMS. The sample including deuterated 17-KS was introduced into TMS derivatives by BSTFA in pyridine. The derived TMS derivatives were analysed using the GC-MS system equipped with the column of 0.5% NPGS Chromosorb W AW DMCS, and the temperature was programmed from 180 degrees C to 240 degrees C at 3 degrees C/min. increment. Seven components were well separated, and each fraction was analysed by MS spectrum. Normal human urine was analysed by this method, the result of which is summarized in Table 3.

17-Ketosteroids↗
PubMed1998

Long-term, quantitative analysis of gametogenesis in autotriploid rainbow trout, Oncorhynchus mykiss.

A long-term, quantitative analysis was conducted on the gametogenesis of autotriploid rainbow trout (Oncorhynchus mykiss) to quantify their degree of germline development and reproductive potential. Triploid and diploid (control) trout siblings were raised separately under identical conditions and sampled randomly for histological analysis. Triploid males underwent testicular development and proliferation of germ cells by mitosis and meiosis, progressing through initial phases of spermatogenesis at a similar pace to diploid controls. The effects of triploidy on males were most evident during the final stages of spermatogenesis, when all diploid males contained free spermatozoa in the lumen of most tubules (average relative frequency, ARF = 68.5%), whereas triploid males contained predominantly spermatocytes (ARF = 36.3%) and morphologically abnormal spermatozoa (ARF = 31.8%). In contrast, the gonadal development of triploid females was affected during its early stages; the major patterns observed were the arrest of the oogonia within oogonial clusters (ARF = 30.4-71.1%), the appearance of small numbers (ARF = 1.5-6.0%) of previtellogenic and early vitellogenic follicles, and the proliferation of non-follicular elements (vascular lacunae, fibrosis and tubular adenomas). In agreement with previous reports on the ovarian development of chromosomally female (3A:ZZW) triploid chickens, male-differentiating areas (ARF = 0.2-12.2%) were observed in most triploid females examined, which by the end of the sampling period appeared as gonadal hermaphrodites. It is hypothesized that the lack of proper somatic-to-germ cell interactions prevents the segregation of the oocytes from the gonial clusters and may explain the early blockage observed during the gonadal morphogenesis of autotriploid female rainbow trout.

Aging↗