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At least 433 records · Page 24Linked to original sources
PubMed1998

A genetic and correlation analysis of liver cholesterol concentration in rat recombinant inbred strains fed a high cholesterol diet.

Liver cholesterol concentration in rats fed a high cholesterol diet, is under genetic control which is supported by significant differences observed among inbred strains. For instance, the Brown Norway (BN-Lx/Cub) rat developed a twofold higher liver cholesterol concentration than the spontaneously hypertensive rat (SHR/Ola). In the current study, we used 30 recombinant inbred (RI) strains, derived from BN-Lx and SHR progenitors, to locate quantitative trait loci (QTL) that are responsible for differences in liver cholesterol concentrations between the BN-Lx and SHR strains. The heritability of liver cholesterol was estimated to be 0.55 and a significant association was detected between concentration of liver cholesterol and the D10Cebrp1016s2 marker on chromosome 10 (lod score = 3.3); this putative QTL was responsible for nearly 64% of additive genetic variability and thus represents a major genetic determinant of liver cholesterol concentration. Liver cholesterol concentrations significantly correlated with intermediate density lipoprotein (IDL) cholesterol levels.

Animals↗
PubMed1992

Correlation analysis between some blood properties and atmospheric environmental parameters.

S.W. Tromp made investigations of a weather effect on erythrocyte sedimentation rates (ESR) of human blood by routine checks of the blood of donor groups in Leiden from 1955 to 1985. A higher ESR was found for the summer season and lower ESR for winter and low values occurred soon after a strong cooling spell. In this report, we have continued his work using data for the years 1971-1985 from Leiden (The Netherlands). An influence of the weather on ESR was also found, but this seems to be more complicated than Tromp supposed. Some new aspects are described and elaborated, e.g. ESR already increases before warming is noticed at the ground layer. This is possibly caused by changes in the upper atmosphere, a suggestion that requires further studies. For periods of low ESR, there was a greater number of occlusion fronts passing the Netherlands. The long-term fluctuations of ESR that were found were correlated with sun spot relative numbers only in a few periods. The results of our study justify further research for a variety of other locations around the world.

Adult↗
PubMed2000

Correlative analysis of the sagittal profile of the spine in patients with beta-thalassemia and in healthy persons.

This prospective study compares several roentgenographic parameters of the thoracic and lumbar spine in patients with beta-thalassemia and in healthy persons who served as controls. Eighty-four patients with beta-thalassemia and 84 age- and gender-matched healthy persons were examined clinically and radiologically (thoracic kyphosis, lumbar lordosis, and vertebral and sacral inclination). Although there was a significant difference in the vertebral inclination from T6 to L1, L4, and L5 between patients and controls, thoracic kyphosis and lumbar lordosis did not differ in the two groups. The apical vertebra of the thoracic kyphosis in patients and controls was T7 and T6, respectively, whereas L4 was the apical vertebra of the lumbar lordosis in both groups. There were no age- or gender-related differences in the magnitude of sacral inclination, thoracic kyphosis, or lumbar lordosis in the patients with beta-thalassemia compared with controls. Lumbar lordosis was significantly correlated with sacral inclination in both patients with beta-thalassemia and controls. Beta-thalassemia does not affect sagittal profile of the thoracic and lumbar spine but it is associated by structural changes on the frontal plane of the spine that are expressed as a high prevalence of scoliosis.

Adolescent↗
PubMed1993

[Transport of ions into human erythrocytes in various forms of hemolytic anemia: a correlation analysis].

The activity of Na+, K(+)-ATPase (ouabain-inhibited 86Rb influx), Na+, K+ cotransport (ouabain-insensitive furosemide-inhibited 86Rb or 22Na influx), Na+/Na+ exchange (ouabain-insensitive phloretin-inhibited 22Na influx) and Na+/Li+ exchange (ouabain-insensitive Na0(+)-depended Li+ efflux) as well as the passive permeability of the erythrocyte membrane for Na+, K+ and Li+ have been studied in patients with primary (microspherocytosis, hemoglobinopathy) and secondary (autoimmune) hemolytic anemia. The activities of the Na+, K(+)-pump and Na+, K(+)-cotransport were increased in patients with microspherocytosis-by 45% and 70%, respectively. In patients with hemoglobinopathy the Na+/Li+ exchange and passive permeability for K+ were increased 2-3-fold in comparison with the control with the control group. The increased passive permeability for K+ may partly be due to the increased K+, Cl(-)-cotransport. In patients with autoimmune anemia the 3-fold increase in the passive permeability for monovalent cations and the 2-fold increased activity of Na+, K+ cotransport were found. There was no significant correlation between the Na+/Na+ and Na+/Li+ exchange which suggests that the cellular mechanisms of activity control in those ion transport systems differ essentially. No correlation was found between the passive permeability for Na+ and K+ either. These data indicate that simple diffusion (leakage) is not the only pathway for the passive permeability of the erythrocyte membrane for monovalent cations.

Adolescent↗
PubMed2003

[Comparison and correlative analysis of pulmonary function markers after extracorporeal circulation].

OBJECTIVE: To compare the clinic significance of three lung function markers after cardiopulmonary bypass operation. METHODS: Twenty-four patients who continuously took selective coronary artery bypass grafting (CABG) with cardiopulmonary bypass in our hospital were separated randomly to AT group and non AT group according the different treatments of the residue blood in extracorporeal circulation (ECC) circuit, 12 patients in each group. The data of hemodynamics and oxygenation after anesthesia induction and 1, 6, 24, 48 h after ECC were recorded. Respiratory index (RI), oxygenation index (OI) and M index (PaO2/PAO2) were counted and compared at the same time. RESULTS: CI, O2ER, DO2I and VO2I were all elevated obviously after ECC, and Qs/Qt were decreased. There were no difference of all these markers between two groups. RI, OI and PaO2/PAO2 did not change during perioperation in AT group, but in non AT group, RI was increased after ECC, company with the decrease of OI and PaO2/PAO2 at the same time. Nevertheless there was no difference between two groups. But the alterations of the marker percentages were more obviously, there were marked differences between the percentages of RI and PaO2/PAO2 24 h after ECC. All three markers had correlation with Qs/Qt and VO2I. CONCLUSION: RI, OI and PaO2/PAO2 all can reflect appropriately the change of lung function after extracorporeal circulation and the monitor of the developmental alterations individually may be more instructive in clinical practice.

Cardiopulmonary Bypass↗
PubMed2000

Morphologic analysis correlates with gene expression changes in cultured F344 rat mesothelial cells.

The gene expression pattern of mesothelial cells in vitro was determined after 4 or 12 h exposure to the rat mesothelial, kidney, and thyroid carcinogen and oxidative stressor potassium bromate (KBrO(3)). Gene expression changes observed using cDNA arrays indicated oxidative stress, mitotic arrest, and apoptosis in treated immortalized rat peritoneal mesothelial cells. Increases occurred in oxidative stress responsive genes HO-1, QR, HSP70, GADD45, GADD153, p21(WAF1/CIP16), GST's, GAPDH, TPX, and GPX-1(0); transcriptional regulators c-jun, c-fos, jun B, c-myc, and IkappaB; protein repair components Rdelta, RC10-II, C3, RC-7, HR6B ubiquitin-conjugating enzyme and ubiquitin; DNA repair components PCNA, msh2, and O-6 methylguanine DNA methyltransferase; lipid peroxide excision enzyme PLA2; and apoptogenic components TNFalpha, iNOS1 and FasL. Decreases occurred in bcl-2 (antiapoptotic), bax alpha, bad, and bok (proapoptotic) and cell cycle control elements (cyclins). Cyclin G and p14ink4b (which inhibit entry into cell cycle) were increased. Numerous signal transduction, cell membrane transport, membrane-associated receptor, and fatty acid biosynthesis and repair components were altered. Morphologic endpoints examined were number of mitotic figures, number of apoptotic cells, and antibody-specific localization of HO-1 (which demonstrated increased HO-1 protein expression). PCR analysis confirmed HO-1, p21(waf1/cip1), HSP70, GPX1, GADD45, QR, mdr1, PGHS, and cyclin D1 changes. A model for KBrO(3)-induced carcinogenicity in the F344 rat mesothelium is proposed, whereby KBrO(3) generates a redox signal that activates p53 and results in transcriptional activation of oxidative stress and repair genes, dysregulation of growth control, and imperfect DNA repair leading to carcinogenesis.

Animals↗
PubMed1997

A correlative analysis of actin filament assembly, structure, and dynamics.

The effect of the type of metal ion (i.e., Ca2+, Mg2+, or none) bound to the high-affinity divalent cation binding site (HAS) of actin on filament assembly, structure, and dynamics was investigated in the absence and presence of the mushroom toxin phalloidin. In agreement with earlier reports, we found the polymerization reaction of G-actin into F-actin filaments to be tightly controlled by the type of divalent cation residing in its HAS. Moreover, novel polymerization data are presented indicating that LD, a dimer unproductive by itself, does incorporate into growing F-actin filaments. This observation suggests that during actin filament formation, in addition to the obligatory nucleation- condensation pathway involving UD, a productive filament dimer, a facultative, LD-based pathway is implicated whose abundance strongly depends on the exact polymerization conditions chosen. The "ragged" and "branched" filaments observed during the early stages of assembly represent a hallmark of LD incorporation and might be key to producing an actin meshwork capable of rapidly assembling and disassembling in highly motile cells. Hence, LD incorporation into growing actin filaments might provide an additional level of regulation of actin cytoskeleton dynamics. Regarding the structure and mechanical properties of the F-actin filament at steady state, no significant correlation with the divalent cation residing in its HAS was found. However, compared to native filaments, phalloidin-stabilized filaments were stiffer and yielded subtle but significant structural changes. Together, our data indicate that whereas the G-actin conformation is tightly controlled by the divalent cation in its HAS, the F-actin conformation appears more robust than this variation. Hence, we conclude that the structure and dynamics of the Mg-F-actin moiety within the thin filament are not significantly modulated by the cyclic Ca2+ release as it occurs in muscle contraction to regulate the actomyosin interaction via troponin.

Actins↗
PubMed2004

CT evaluation of the response of gastrointestinal stromal tumors after imatinib mesylate treatment: a quantitative analysis correlated with FDG PET findings.

OBJECTIVE: We correlated changes in tumor density on CT with changes in glucose metabolism, or the maximum standardized uptake value (SUV(max)), on FDG PET and sought to develop CT imaging criteria that can be used to objectively evaluate tumor response in patients with metastatic gastrointestinal stromal tumors (GISTs) who undergo treatment with imatinib mesylate. MATERIALS AND METHODS: Using the criteria established by the Response Evaluation Criteria in Solid Tumors (RECIST) group, we selected 173 tumors (in 36 patients) for study. Tumor size and density were determined objectively, and overall tumor response (OTR) was evaluated subjectively on CT images. The changes in these parameters before and after treatment were correlated with changes in SUV(max). RESULTS: Significant decreases were seen in both tumor density (mean, 12.3 H [16.5%]; p < 0.0001) and SUV(max) (mean, 3.43 [64.9%]; p < 0.0001). OTR evaluated subjectively, correlated well with changes in SUV(max) (p < 0.0001). No statistically significant association was found between changes in tumor density and changes in SUV(max) (p = 0.3088), but 70% (14/20) of the patients with tumors that showed response on FDG PET exhibited at least a partial response by a change in tumor density. Tumor size was found to have decreased significantly 2 months after treatment (p = 0.0070). However, in 75% of the patients, the disease was stable according to the traditional tumor response criteria of RECIST. CONCLUSION: FDG PET is sensitive and specific for evaluating tumor response but cannot be used in patients whose baseline FDG PET results are negative for tumors. Although subjective evaluation was a better indicator of treatment response than was tumor density alone, the tumor density measurement is a good indicator and provides a reliable quantitative means of monitoring the tumor. RECIST, using only tumor size, was unreliable for monitoring GISTs during the early stage of imatinib mesylate treatment.

Adult↗
PubMed1999

Region-specific encoding of sensory and affective components of pain in the human brain: a positron emission tomography correlation analysis.

Brain imaging with positron emission tomography has identified some of the principal cerebral structures of a central network activated by pain. To discover whether the different cortical and subcortical areas process different components of the multidimensional nature of pain, we performed a regression analysis between noxious heat-related regional blood flow increases and experimental pain parameters reflecting detection of pain, encoding of pain intensity, as well as pain unpleasantness. The results of our activation study indicate that different functions in pain processing can be attributed to different brain regions; ie, the gating function reflected by the pain threshold appeared to be related to anterior cingulate cortex, the frontal inferior cortex, and the thalamus, the coding of pain intensity to the periventricular gray as well as to the posterior cingulate cortex, and the encoding of pain unpleasantness to the posterior sector of the anterior cingulate cortex.

Adult↗
PubMed1982

Heterogeneity of soluble T cell products. I. Precursor frequency and correlation analysis of cytotoxic and immune interferon (IFN-gamma)-producing spleen cells in the mouse.

In this study, the precursor frequency, relationship and activity of murine splenic cytotoxic and immune interferon (IFN-gamma)-producing cells has been determined. C57BL/6 spleen cells were activated by concanavalin A (Con A) and subsequently grown in microcultures under limiting dilution conditions. The progeny of cells plated in microcultures was divided and tested for (a) total cytotoxic activity on EL4 (H-2b) tumor target cells in the presence of Con A to nonspecifically attach the killer to the target cells, and (b) the quantity of IFN-gamma released by Con A stimulation. Cytotoxic T lymphocytes and IFN-gamma-producing cells were present in Con A-activated C57BL/6 spleen cells at a high frequency of approximately 1 out of 3 and 1 out of 2 cells, respectively. IFN-gamma could be released from both noncytotoxic and a large fraction of cytotoxic T cells and the cytotoxic activity was not necessarily associated with IFN-gamma release. In a few selected cultures with a progeny of cells plated at a low cell number (up to 10/well) very high IFN-gamma titers (greater than 10 000 U/ml) could be found. These results provide the first frequency estimate of IFN-producing cells and are discussed with respect to the physiological role of IFN-gamma release from T cells.

Animals↗
PubMed2002

Ten-Point Clock Test: a correlation analysis with other neuropsychological tests in dementia.

BACKGROUND: Neuropsychology can be useful for differentiating patients with fronto-temporal dementia (FTD) from those with Alzheimer disease (AD) and those with Vascular Dementia (VaD). OBJECTIVES: The purpose of this study was twofold: to explore possible employment of the Ten-Point Clock Test in early identification of different types of cognitive distribution and to relate to its execution to other specific impairment, bound to the selected pathology. METHOD: We compared 30 patients with FLD, to a group of 30 probable-AD patients accordingly to the NINCDS-ADRDA criteria, and to a group of 30 probable VaD patients, according to the NINDS-AIREN criteria. RESULTS: AD group showed the worst results in Clock Drawing Test. On the contrary, FLD group did produce the worst performances in Proverb Interpretation Tasks. VaD worst performance was that of phonological fluency. Our data seem to demonstrate that in mild dementia, stated by the MMSE score (around 22) and confirmed by the data derived from the other neuropsychological evaluation, the Clock Drawing Test is quite sensitive to detect cognitive impairment, even if of different origins. CONCLUSIONS: Ten-Point Clock Test is a strong tool, in order to identify early forms of Alzheimer, and to help differential diagnosis when frontal or vascular dementia have been taken into account. More data will be necessary to give to this speculative interpretation, a neuroimaging and neuroanatomical support. However, this report may encourage the wider use of this parametric test, easily applicable and well accepted by the population in order to implement data concerning cognitive disruption.

Aged↗
PubMed1984

Oral contraceptives containing chlormadinone acetate and cancer incidence at selected sites in the German Democratic Republic--a correlation analysis.

The use of oral contraceptives containing chlormadinone acetate in 1972 by women of 13 districts (out of 15) of the GDR has been related to the incidence of cancer of breast, corpus uteri, and ovary during the period 1961 to 1980. Cancer incidence was represented by cohort parameters showing the risk of the cohorts in relation to each other. No statistically significant association between the two events was noted. Although not significant, our data are consistent with an elevated relative risk for breast cancer of 1.3 and a decreased risk for ovarian cancer of 0.5.

Adult↗
PubMed2007

Nested, non-parametric, correlative analysis of microarrays for heterogenous phenotype characterization.

We present a non-parametric approach for qualitatively selecting candidate genes to characterize several criteria that are nested among genes selected on the basis of their individual, similar effects upon an array-wide closeness measure. In this setting, a goal is to obtain a reliable characterization of phenotypes, based on very high-dimensional data from a few samples. As opposed to a distance-based approach, the proposed measure defines closeness based on gene signal profiles (functionals) rather than on isolated (numerical) differences in each gene between samples. By using such a measure to characterize intensity differences, we effectively separate biological from artifactual variation in expression, due to tissue effects or signal calibration. Based on this measure, we successively examine the significance of the following: a set of similarly behaved genes relative to all arrayed genes, a set of candidate genes relative to similarly behaved genes, individual candidate genes relative to non-candidates, and the direction, as over- or under-expressed, of candidate genes. In each setting, sample pairs are the units of analysis, with U-statistics the theoretical framework. We illustrate the method on a microarray experiment, where the goal is to select sets of genes that characterize a type of skin cancer and its histological subtypes.

Genetic Heterogeneity↗
PubMed1994

Methodology, correlational analysis, and interpretation of diet diary records of the food and fluid intake of free-living humans.

The diet diary technique can produce reliable and valid records of the food and fluid intake of free-living humans. Procedures to maximize accuracy by motivating subjects, verifying records and minimizing bias are described. Underestimation and random error may tend to obscure relationships but does not artifactually produce them. Meal pattern analysis of the diary records relates the meal size, composition and intermeal interval to preceding conditions with univariate and multivariate regression techniques. Although causation cannot be conclusively demonstrated, the analyses can test for potential causal influences. It is concluded that the diet diary technique is the method of choice for investigations of the ingestive behaviours of free-living humans.

Data Interpretation, Statistical↗
PubMed2001

Genetic and correlation analysis of hepatic copper content in the rat.

Thirty recombinant inbred (RI) strains derived from the spontaneous hypertensive rat (SHR/OlaIpcv) and the Brown Norway (BN-Lx/Cub) progenitors were used to search for quantitative trait loci (QTLs) that are responsible for differences in liver copper between these two strains. The heritability of liver copper concentration (expressed as microg/g liver wet wt and microg/g liver dry wt) and liver copper store (microg/whole liver) was estimated to be 57, 57, and 46%, respectively. In a total genome scan of the RI strains, involving over 600 genetic markers, suggestive association was found between liver copper store (microg/whole liver) and the D16Wox9 marker on chromosome 16 (lod score = 2.8), and between liver copper concentration (microg/g dry wt) and the D10Cebrp1016s2 marker on chromosome 10 (lod score = 3.0). These putative QTLs are responsible for nearly 34 and 40% of the additive genetic variability for liver copper store and concentration, respectively.

Animals↗