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PubMed2006

[Correlation of obesity with C-reactive protein, leptin and insulin sensitive index in children].

OBJECTIVE: To study the correlation between obesity and hypersensitive C-reactive protein (hsCRP), leptin, and insulin sensitive index (ISI) in children. METHODS: The subjects included 69 obese volunteers and 30 age and gender-matched normal volunteers who were recruited from 13702 children aged 2 to 18 years in Xiangtan City by sampling survey. The body mass index (BMI), hsCRP, leptin, fasting plasma glucose (FPG), and fasting insulin (INS) were tested, and then the ISI was calculated. The results between the obese and normal children were compared. The correlation between the parameters was evaluated. RESULTS: The values of hsCRP, leptin and INS in obese children were significantly higher than those in the normal controls (P < 0.01), but the ISI in obese children was significantly lower than that in normal controls (P < 0.01). The BMI was significantly positively correlated with the values of hsCRP, leptin and INS (r=0.225, P < 0.05; r=0.776, P < 0.01; r=0.568, P < 0.01), but was significantly negatively correlated with the ISI (r=-0.889, P < 0.01). There was a positive correlation between the value of hsCRP and the values of FPG and INS (r=0.429, P < 0.01; r=0.206, P < 0.05), and there was a negative correlation between the value of hsCRP and the ISI (r=-0.889, P < 0.01). The value of leptin significantly positively correlated with the values of INS and BMI, and significantly negatively correlated with the ISI. CONCLUSIONS: Insulin resistance and leptin resistance exist in obese children. The inflammatory factors such as CRP and leptin may be involved in the pathogenesis of obesity.

Adolescent↗

PubMed2006

[Correlation of antitumor drug sensitivity between marrow mesenchymal stem cells (MSCs) and hepatocarcinoma cells in rats].

BACKGROUND & OBJECTIVE: As hepatocarcinoma stem cells may originate from oval cells and oval cells are difficult to be separated and purified, MSCs (marrow mesenchymal stem cells), which are the progenitor cells of the hepatocarcinoma stem cells, were selected instead in our study to investigate the correlation of anticancer drug sensitivity between hepatocarcinoma cells and MSCs in rats. METHODS: The primary liver carcinoma modle of rats was induced by diethylnitrosamine. Tumor cells and MSCs from eight hepatocarcinoma rats were separated. The inhibitory effects of 3 anticancer drugs [adriacin (0.04 microg/ml), cisplatin (0.2 microg/ml) and fluorouracil (1 microg/ml)] to hepatocarcinoma cells and MSCs were measured by MTT assay. The weight of the tumor in nude mice which were injected with rat hepatocarcinoma cells was measured after 6 weeks. Then the correlation of the inhibitory ratio of 3 anticancer drugs to hepatocarcinoma cells and MSCs, and to the tumor weight of nude mice was analyzed. RESULTS: No correlation was revealed between the inhibitory ratio of 3 anticancer drugs to hepatocarcinoma cells and the tumor weights of nude mice injectal with drug treated tumor cells. The correlation coefficient was: 0.6307 (adriacin, P>0.05), 0.4358 (fuiorouracil, P>0.05) and 0.7080 (cisplatin, P>0.05). No correlation was observed between the inhibitory ratio of 3 anticancer drugs to hepatocarcinoma cells and to MSCs. The correlation coefficient was: 0.6316 (adriacin, P>0.05), 0.4214 (fluorouracil, P>0.05) and 0.5943 (cisplatin, P>0.05). However, significant reverse correlation was found between the inhibitory ratio of 3 anticancer drugs to MSCs and the tumor weights of nude mice injectal with drug treated tumor cells. The correlation coefficient was: -0.8308 (adriacin, P<0.05), -0.8991 (fluorouracil, P<0.01) and -0.8311 (cisplatin, P<0.05). CONCLUSIONS: Conventional anticancer drug sensitivity experiments could not reflect the chemoresistance of the hepatocarcinoma cells. However the inhibitory ratio of the anticancer drugs to MSCs in the hepatocarcinoma rats can reflect the chemoresistance of hepatocarcinoma cells accordingly.

Animals↗

PubMed2007

[Correlation of p38 mitogen-activated protein kinase signal transduction pathway to uPA expression in breast cancer].

BACKGROUND & OBJECTIVE: p38 mitogen-activated protein kinase (p38MAPK) signal transduction pathway regulates the expression of various metastasis-related genes. Urokinase-type plasminogen activator (uPA) plays an important role in cancer invasion and metastasis. This study was to explore the correlation of p38MAPK signal transduction pathway to uPA expression in breast cancer. METHODS: SP immunohistochemistry was used to test the expression of p-p38, p-Akt, p-Erk, and uPA in 60 specimens of breast cancer. Western blot was used to detect the protein levels of p-p38 and uPA in breast cancer MDA-MB-231 and MCF-7 cells and the protein level of uPA in MDA-MB-231 cells after blocking p38MAPK signal transduction pathway by SB203580, a specific inhibitor of p38MAPK. The correlations of p-p38, p-Akt, p-Erk, and uPA expression to the clinicopathologic characteristics of breast cancer, and the correlations of p-p38, p-Akt, and p-Erk expression to uPA expression were analyzed. The mechanism of p38MAPK signal transduction pathway regulating the protein expression of uPA in breast cancer cells was investigated. The correlation of p-p38 and uPA expression to prognosis of breast cancer was analyzed. RESULTS: The positive rates of p-p38, p-Akt, p-Erk, and uPA proteins in breast cancer tissues were 56.7%, 95.0%, 93.3%, and 60.0%, respectively. The expression of p-p38 was positively correlated to the expression of uPA (r=0.316, P<0.05), while the expression of p-Akt and p-Erk was not related to uPA expression. The expression of p-p38 and uPA was correlated to lymph node metastasis and TNM stage (P<0.05), but not to patients' age and tumor size (P>0.05). The expression of p-Akt and p-Erk were correlated to lymph node metastasis (P<0.05), but not to TNM stage, patients' age, and tumor size (P>0.05). The protein levels of p-p38 and uPA in MDA-MB-231 cells were higher than that in MCF-7 cells. SB203580 concentration-dependently inhibited p38MAPK pathway and induced uPA protein expression. The expression of p-p38 and uPA was negatively correlated to prognosis of breast cancer (log-rank=4.98, 5.40, P=0.026, 0.020). CONCLUSIONS: p38MAPK signal transduction pathway might improve breast cancer progression by up-regulating uPA expression, and might be an important route in invasion and metastasis of breast cancer. p-p38 and uPA might help to evaluate prognosis of breast cancer.

Adult↗

PubMed1989

[Significant correlations of mortality due to stomach and colonic cancer in Rosario with other neoplastic sites].

The age standardized mortality rates, by sex, for cancer all sites and some diagnostic sites were calculated in the 22 Areas of the city of Rosario during the period 1977-81. The rates of the different cancer sites, by Areas, were correlated with stomach and colon cancers, by sex, applying the Kendall's tau, a non-parametric method of correlation. While the mortality rates for cancer all sites and for stomach cancer in males were higher than in females in almost all of the Areas, for colon cancer they were almost similar. Colon cancer rates in both sexes had negative correlations with infant mortality rates, and in females had positive correlations with breast cancer, and negative correlations with cervix and uterus cancer. Stomach mortality rates had negative correlations with those of colon in both sexes, and positive correlations with total cancer and infant mortality rates. The distribution of the mortality rates of some cancer sites and their correlations suggest that some risk factors and shared in their causal chain.

Argentina↗

PubMed1988

Single unit analysis of the human ventral thalamic nuclear group: correlation of thalamic "tremor cells" with the 3-6 Hz component of parkinsonian tremor.

Although cells firing at tremor frequency, called "tremor cells" (Guiot et al., 1962), have often been recorded in the thalamus of parkinsonian patients, the extent of correlation between these spike trains and tremor has rarely been assessed quantitatively. This paper describes spectral cross-correlation functions calculated between the activity of "tremor cells" and electromyogram (EMG) signals recorded from several muscles in the contralateral arm. The power occurring in the spike train at tremor frequency was described in absolute terms by the spike autopower, and in relation to the average for all spectral components by the spike autopower signal-to-noise ratio (spike autopower SNR). The probability of significant cross-correlation between the thalamic spike train and EMG at tremor frequency was assessed by the coherence at tremor frequency. Autopower spectra of the activity of many of these cells exhibited a concentration of power at tremor frequency, indicated by spike autopower SNRs as high as 18. Of the EMG signals studied, signals recorded from finger flexors were most often significantly correlated at tremor frequency. Significant correlation between the thalamic spike train and finger flexor EMG activity was found in 34% of cells analyzed. Tremor frequency coherence was significantly correlated with tremor frequency spike autopower (r = 0.46, p less than 0.0001) and spike autopower SNR (r = 0.533, p less than 0.0001). The proportion of cells with a spike autopower SNR greater than 2 that were significantly correlated with finger flexor EMG activity was greater than that of cells with a spike autopower SNR of less than 2 (p less than 0.001; chi-square). Therefore, cells exhibiting a large amount of power at tremor frequency were those best correlated with EMG activity during tremor. Some of these cells may be involved in the generation of tremor.

Action Potentials↗

PubMed1983

Correlation of incidence rates for selected cancers in 29 census sub-divisions of Alberta, Canada, 1961-1981.

Age-adjusted incidence rates for males and females for 36 cancer sites across 29 census sub-divisions of the province of Alberta were correlated with one another. It was hypothesized that cancers which vary together across geographical areas may have common aetiological factors. The correlations were measured by the Pearson product moment coefficient, r, and illustrated by scatter graphs and regression lines. For males moderate correlations were found between prostate and skin cancer and between prostate cancer and non-Hodgkin's lymphoma. Also moderately correlated were male stomach and small intestine cancers and cancers of the bladder and the buccal cavity and pharynx. Specific site correlations for cancers in females were generally higher than for cancers in males. The highest correlations were found between cancer of cervix (invasive) and cancer of trachea, bronchus and lung, between multiple myeloma and cancer of brain and nervous system, between acute lymphatic leukemia and cancer of the bone and connective tissue, and between melanoma and cancer of bone and connective tissue. Although all these correlations are moderate they nevertheless indicate substantial relationships. Possible common aetiologic factors for correlating pairs of cancers are discussed.

Alberta↗

PubMed1982

Correlative design of electrophoretic and ultracentrifugal investigation of metabolic effects of probucol.

Probucol demonstrated a profound metabolic effect on the metabolism of plasma lipoproteins by lowering the levels of circulating low-density lipoproteins (LDL). This main metabolic phenomenon was usually accompanied with other substantial events in lipoprotein patterns. Their significance ought to be confirmed by more than one analytical method. Our primary analytic system used for the basic analysis of plasma lipoproteins consisted of analytical ultracentrifugation, highly standardized agarose-gel electrophoresis and molecular separation of lipoproteins according to their molecular sizes. This paper refers to an attempt to endorse electrophoresis as a supporting technique for ultracentrifugal studies. Correlation between corresponding ultracentrifugal classes and electrophoretic fractions, declared by their coefficients, were therefore studied in order to further examine the usefulness and applicability of agarose-gel electrophoresis in the research, as well as in determining and monitoring patient therapy. Close correlations were found between the group of chylomicrons (CHY), very-very-low-density lipoproteins (VVLDL), very-low-density lipoproteins (VLDL), intermediate-density lipoproteins (IDL), their remnants and the entire pre-beta-electrophoretic complex of plasma lipoproteins (r=0.91). CHY, VVLDL and VLDL were also well related to the alpha 2- and pre-beta 2-electrophoretic fraction (r=0.95). However, if we consider concentration units for comparison of the relation between pre-beta 1- and beta-electrophoretic fractions versus all sub-classes of LDL, such correlation was found weaker (r=0.77); results were similar when such correlation was made with HDL2,3 classes versus alpha electrophoretic fractions (r=0.78). On the contrary, when the relative percentage in the spectra of the same classes and fractions were correlated, the correlation coefficients were different: CHY and all subclasses and remnants of VLDL, versus the entire pre-beta-electrophoretic complex demonstrated r=0.87, versus the alpha 2- and pre-beta 2-electrophoretic fraction r=0.73. The electrophoretic pre-beta 1-beta-complex correlated weakly (r=0.50) with low and medium density lipoproteins (MDL). Unexpectedly tight (r=0.89) was the correlation between relative percentages of the electrophoretic alpha 1-fraction and the high-density lipoproteins (HDL).

Blood Protein Electrophoresis↗

PubMed1982

Correlations between quantum chemical indices and carcinogenicity of methylbenz(a)anthracenes, methylbenzacridines and their model metabolites.

Carcinogenic activity of methyl derivatives of benz(a)anthracene and benzacridines has been correlated with the indices of electronic structure representing the reactivity and lipophilic coefficients of the compounds. The effect of the enzyme oxidase on the compounds has been stimulated and considered in correlations. The correlations with carcinogenic activity have been shown to be important from the statistical point of view: 1. correlation of the indices representing the lipophilic coefficient of the original compounds; 2. correlation of HOMO energies representing ease of formation of radical cations; 3. correlation of the reactivity indices in the A-region in the model complex of the studied derivatives and enzyme; 4. correlation of the reactivity indices of ultimate "carbonium" triol. Of these correlation equations only the equation 3 has shown wider applicability (i. e. also for benzacridines).

Acridines↗

PubMed1994

Phospholipase A2 in juvenile rheumatoid arthritis: correlation to disease type and activity.

OBJECTIVE: Secretory nonpancreatic phospholipase A2 (snpPLA2) is a proinflammatory enzyme and its activity in serum correlates with disease activity in adults with rheumatoid arthritis. Juvenile rheumatoid arthritis (JRA) may be stratified into 3 clinical types with differing degrees of disease activity. Since in JRA there are no reliable indices of disease activity, our objective was to find whether the level of circulating snpPLA2 correlates with the severity of inflammation and with JRA activity. METHODS: PLA2 enzymatic activity was assayed using E. coli membranes labelled with (14C)-oleic acid. SnpPLA2 immunoreactivity was tested by ELISA technique using monoclonal antibodies against recombinant human (rh) snpPLA2. SnpPLA2 activity was determined in sera of 127 children including 25 with systemic (S-JRA), 50 with polyarticular (Po-JRA) and 52 with pauciarticular (Pa-JRA) types of JRA. Twenty-five patients with active disease, were subsequently restudied in an inactive phase. RESULTS: Markedly increased snpPLA2 (> mean + 2 SD of normal mean, i.e., > 575 U/ml) was found during the active disease in 100% S-JRA, 57% Po-JRA and 25% Pa-JRA patients. The differences in the mean and median PLA2 activity among these 3 subtypes of JRA were highly significant (p < 0.001) with the highest levels found in S-JRA and the lowest in Pa-JRA. Presence of rheumatoid factor and/or of antinuclear antibody had no relation to the level of snpPLA2. SnpPLA2 activity became markedly lower when active inflammation became quiescent. In the whole group, snpPLA2 activity correlated highly with the Lansbury index, number of involved joints and number of effusions. A significant positive correlation was also found between snpPLA2 and erythrocyte sedimentation rate (ESR) and neutrophil count, while a significant negative correlation was noted with the level of albumin and hemoglobin. With the exception of snpPLA2, other laboratory variables did not correlate with the number of effusions or the number of active joints. However a negative correlation was noted between both hemoglobin and albumin, and Lansbury index. CONCLUSION: Circulating snpPLA2 significantly correlates with JRA activity and may serve as an index of activity in JRA especially in patients with systemic type of disease.

Adolescent↗

PubMed1994

Altered levels of erythrocyte calcium-binding proteins in essential hypertensives with genetic predisposition: correlation with ambulatory blood pressure.

OBJECTIVE: To examine whether changes in calcium-binding proteins, one of the components of the calcium ion handling mechanism, occur in humans with essential hypertension. DESIGN: We measured the levels of cytosolic calcium-binding proteins purified from human erythrocytes using a felodipine fluorescence assay, and examined the correlation between this parameter and the ambulatory blood pressure (ABP). We divided 127 subjects into four age-matched groups according to their mean ABP levels and whether they had a family history of both hypertension and stroke [group A hypertensives with a positive family history (n = 30), group B hypertensives with no family history (n = 31), group C normotensives with a family history (n = 31) and group D normotensives with no family history (n = 35) of hypertension and stroke]. RESULTS: The erythrocyte cytosolic level of calcium-binding proteins in group A was significantly lower than that in group B, as was that in group C compared with group D. There was no significant correlation between the erythrocyte level of calcium-binding proteins and casual blood pressure values in any group. However, in group A significant negative correlations between the erythrocyte level of calcium-binding proteins and systolic and mean ABP were observed (r = -0.34, P < 0.05 and r = -0.39, P < 0.05, respectively). No significant correlations between the ABP and erythrocyte levels of calcium-binding proteins were observed in the other groups. When each group was subdivided according to sex, there were significant negative correlations between the erythrocyte level of calcium-binding proteins and the systolic and mean ABP in the males of groups A and C, but no correlations were found in any of the female subgroups or the males of groups B and D. Reducing the blood pressure by antihypertensive drug therapy did not affect the erythrocyte calcium-binding proteins level in 13 patients from groups A and B. Analysis using anion-exchange fast-performance liquid chromatography on a Mono-Q column and sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed that the calcium-binding proteins in human erythrocytes, the levels of which were low in group A, formed a single protein band with a molecular weight of 17,000, which was assumed to be a calmodulin. CONCLUSIONS: These results suggest that there are subgroups of hypertensive patients with low erythrocyte cytosolic levels of calcium-binding proteins, which are genetically determined. Furthermore, our data suggest that the erythrocyte level of calcium-binding proteins and ABP in male subjects with hypertension and normotensives with a genetic predisposition are correlated strongly, whereas no such correlation was observed in any female subgroup. This indicates that the regulatory mechanism or mechanisms involved in the control of blood pressure in men and women may be different.

Aging↗

PubMed1994

Correlations of family medicine clerkship evaluations with scores on standard measures of academic achievement.

BACKGROUND: The family medicine clerkship at the University of Arizona uses three methods to evaluate students. The purpose of this study is to 1) look for possible sources of bias in each method, 2) validate the evaluation methods by correlating with other measures of academic achievement, and 3) measure the amount of correlation between the three evaluation methods. METHODS: The three clerkship evaluation methods include a final exam, clinical evaluations, and problem-solving scores. The clerkship evaluations received by 482 students were correlated with undergraduate grade point averages, MCAT scores, National Board of Medical Examiners parts I and II subtests and total scores, gender, age, race, college major, and timing of the clerkship. RESULTS: Females and older students scored higher on problem solving and minority students scored lower on the final exam. Students in the second half of the year scored higher on the final exam. There were significant correlations found between the final exam score and all the scores on standard measures of academic performance except the MCAT quantitative subtest. Problem-solving scores correlated only with NBME part II. The clinical evaluations correlated with five NBME part I subtest scores, three NBME part II subtest scores, and both parts I and II total scores. All three evaluation methods correlated significantly with each other. CONCLUSIONS: These analyses highlight the need to examine all evaluation methods used in order to improve their validity and reliability and to find potential biases. In addition, more work is needed to document the predictive validity of clerkship evaluations by correlating them with future clinical performance.

Age Factors↗

PubMed1996

Binaural cross-correlation predicts the responses of neurons in the owl's auditory space map under conditions simulating summing localization.

Summing localization describes the perceptions of human listeners to two identical sounds from different locations presented with delays of 0-1 msec. Usually a single source is perceived to be located between the two actual source locations, biased toward the earlier source. We studied neuronal responses within the space map of the barn owl to sounds presented with this same paradigm. The owl's primary cue for localization along the azimuth, interaural time difference (ITD), is based on a cross-correlation-like treatment of the signals arriving at each ear. The output of this cross-correlation is displayed as neural activity across the auditory space map in the external nucleus of the owl's inferior colliculus. Because the ear input signals reflect the physical summing of the signals generated by each speaker, we first recorded the sounds at each ear and computed their cross-correlations at various interstimulus delays. The resulting binaural cross-correlation surface strongly resembles the pattern of activity across the space map inferred from recordings of single space-specific neurons. Four peaks are observed in the cross-correlation surface for any nonzero delay. One peak occurs at the correlation delay equal to the ITD of each speaker. Two additional peaks reflect "phantom sources" occurring at correlation delays that match the signal of the left speaker in one ear with the signal of the right speaker in the other ear. At zero delay, the two phantom peaks coincide. The surface features are complicated further by the interactions of the various correlation peaks.

Animals↗

PubMed1996

Measurement of serum hyaluronic acid in patients with rheumatoid arthritis: correlation with disease activity.

OBJECTIVE: To examine serum concentrations of hyaluronic acid (HA) in patients with rheumatoid arthritis (RA) and to investigate the relationship between clinical measures of disease activity and serum HA concentrations in these patients. METHODS: Sixty-five patients with established RA were enrolled and RA disease activity was measured by clinical variables. Serum samples obtained at the time of the clinical evaluation were assayed for serum HA, erythrocyte sedimentation rate (ESR), and C reactive protein (CRP), and correlations between these laboratory variables and clinical disease activity were sought. RESULTS: Concentrations of serum HA were higher in patients with RA than in healthy controls. There was statistically significant correlation between patient age and serum HA and between serum HA and disease activity measured by physician assessment and number of swollen joints. Correction for age strengthened the correlation between serum HA and measures of disease activity. ESR did not correlate with any measure of clinical disease activity. CRP concentrations correlated with physician assessment of disease activity, and number of swollen joints and tender joints, but the correlation was not as strong as the correlation between serum HA and disease activity variables. CONCLUSION: Measurement of serum HA may be a useful measure of disease activity in patients with RA. Measurement of serum HA appears to be a better correlate of clinical disease activity in patients with RA than ESR or CRP.

Adult↗

PubMed1996

[Correlation between QT interval dispersion and ventricular arrhythmia in hypertension].

OBJECTIVE: To evaluate the correlation between QT interval dispersion (QTd) and ventricular arrhythmias in hypertensive patients (pts) with or without left ventricular hypertrophy (LVH). A secondary aim was to investigate correlations of QTd with other markers of arrythmogenic propensity: ventricular late potentials (LP) and heart rate variability (HRV). METHODS: We retrospectively measured the QTd on the 12 standard surface ECG leads in 230 hypertensive pts (94F, 136M; 59.6 +/- 12.7 years old). A 24 hours ECG Holter recording was performed in 218 pts and ventricular arrhythmias were appreciated using the Lown classification. Left ventricular mass was determined by echocardiography (LVM-Devereux formula) and left ventricular mass index (LVMI) were determined in 202 subjects. LP (122 pts) and HRV (55 pts) were investigated. RESULTS: The QTd varied between 20 and 160 msec (57.8 +/- 32.7 msec). The distribution of pts classified using Lown criteria was: 29 pts (13.3%) class O; 106 pts (48.6%) class I; 8 pts (3.6%) class II; 13 pts (6%) class III; 29 pts (13.3%) class IVa; 33 pts (15.1%) class IVb; 116 pts (69.5%) had LVH determined by echocardiography. The QTd was strongly correlated with the Lown classes (p < 0.0001). The QTd was significantly broader in Lown classes III, IVa and IVb compared to classes O, I and II cumulated (p < 0.002); there was no difference concerning QTd between Lown classes III, IVa and IVb. The QTd was also correlated with the absolute number of premature ventricular depolarizations/24 hours (p = 0.02; r = 0.16). The 75 pts with an increased LVMI had significantly elevated QTd compared to pts without it (p < 0.0001). Qtd was correlated with LVMI (r = 0.37; p < 0.0001). There was no correlation between QTd and the existence of LP (which were correlated with the Lown classes; p < 0.03) and HRV parameters. CONCLUSION: Elevated QT interval dispersion is associated with more severe ventricular arrhythmias in hypertensive subjects with LVH. The mechanism of an increased inhomogeneity of repolarisation is probably related to the anatomic modifications induced by LVH. No significant correlation between QTd, LP and HRV was observed.

Aged↗

PubMed1996

Breast carcinoma. Correlations between visual diagnostic criteria for histologic grading and features of image analysis.

OBJECTIVE: To investigate the relevance of image analysis for grading breast carcinomas. STUDY DESIGN: The results of histologic grading were correlated with 18 features of image analysis, including SD. "Simple" characteristics, like area and perimeter, shape indices, optical density and textural features of nuclei from cancer cells, were analyzed. Hematoxylin-eosin-stained tissue sections of 67 cancer specimens were routinely used for the study. RESULTS: We found statistically significant correlations between overall histologic grading and the sum of its subscores and features of image analysis, especially nuclear area, nuclear perimeter and the diameter of the circumscribing circle (diametercirc), including their SDs. The visually and therefore subjectively assessed subscore of the nuclear pleomorphism of histologic grading significantly correlated with the features of image analysis, like nuclear area, nuclear perimeter, diametercirc, integrated optical density and correlation (and their SDs). There were significant relationships between the absolute numbers of mitoses per 10 high-power fields and nuclear area, nuclear perimeter and diametercirc (and their SDs). We did not observe a significant correlation between the subscore of tubule formation of histologic grading and any of the features of the image analysis studied. Furthermore, the correlations between the features of image analysis and the subscores of the visual histologic grading system were analyzed with respect to each other. The subscore of nuclear pleomorphism of histologic grading correlated best with overall grading (r = .72), whereas no significant correlation could be found between the subscores of nuclear pleomorphism and mitotic activity. CONCLUSION: Image analysis provides objectivity and reproducibility to the grading of breast carcinomas and thus could contribute to more individualized prognostication of the disease.

Breast Neoplasms↗

PubMed1996

[Correlation between aortic transvalvular gradient obtained with Doppler ultrasonography and with hemodynamics study. Role of the underlying etiology].

In aortic stenosis, a good correlation was found between the gradients obtained by catheterization and Echo-Doppler. However, the correlation of these two methods in subgroups of patients with different etiologies of aortic stenosis is unknown. The aim of this study was to evaluate, whether the correlation between catheterization and Echo-Doppler was similar in patients with different etiologies of aortic stenosis. Patients with concomitant valvular disease were excluded. Only patients with a clearly defined etiology (based on clinical history, echocardiography, angiography and/or pathology) were included in this study. We evaluated 106 patients with aortic stenosis. Forty-nine patients had degenerative aortic stenosis, 32 bicuspid aortic stenosis and 25 rheumatic aortic stenosis. The percentage of male patients in each group were as follows: 57.1% in the denerative aortic group; 62.5% in the bicuspid aortic stenosis group; and 76% in the rheumatic aortic stenosis group. Mean age (years) was 69 +/- 6.7 in the degenerative aortic stenosis group, 58.1 +/- 7.5 in the bicuspid aortic stenosis group, and 64 +/- 7.1 in the rheumatic aortic stenosis group. In our study we found different correlations between the gradients obtained by the two methods-catheterization and Eco-Doppler-among the patients with different etiologies of aortic stenosis. The correlation coefficient (r2) was 0.54 (p < 0.001) in the rheumatic aortic stenosis group, 0.37 (p < 0.001) in the bicuspid aortic stenosis group and 0.21 (p = 0.001) in the degenerative aortic stenosis group. In conclusion, a good overall correlation was found between the two methods in aortic stenosis, however, this correlation is different in the three etiologies of aortic stenosis. The correlation is better in rheumatic valves, intermediate in bicuspid valves, and worse in degenerative valves. Changes in aortic valve morphology in these subgroups of patients are probably responsible for these different results.

Aged↗

PubMed1997

Similarities inferred from the studies of long range correlations among mitochondrial DNA sequences.

Existence of long range correlations within the DNA sequences of living organism has immense importance in understanding the language of DNA sequences. Recently it has been reported that long range correlations occur in DNA sequences. Some investigators claimed that these type of correlations occur only on intron containing DNA sequences. Some observers, however, have the opinion that long range correlations do not distinguish between the intron containing DNA sequences and intronless DNA sequences. The biological origin of long range correlations in the DNA sequences is not clearly known. In this paper we have demonstrated that long range correlations also occur on intronless mitochondrial DNA sequences, indicating that these special type of correlations are not the unique features for intron containing DNA sequences. We have also demonstrated that long range correlations simply originate in the region around which there is a large variation of pyrimidine and purine ratios. The similarities among the mitochondrial DNA sequences can be inferred by computing the fractal exponents in the region where there is a large variation of pyrimidine and purine ratio, as well as in the region where the ratio of pyrimidine and purine fluctuates in a nearly constant manner. In other words the similarities among the mitochondrial DNA sequences cannot be inferred by calculating the fractral exponents for the whole sequence.

Animals↗

PubMed1998

Ambulatory 24-hour blood pressure monitoring: correlation between blood pressure variability and left ventricular hypertrophy in untreated hypertensive patients.

BACKGROUND: Left ventricular hypertrophy (LVH) appears to be poorly correlated with clinical measurements of blood pressure: a better correlation may be observed with data from 24 h ambulatory blood pressure monitoring (ABPM). The aim of this study was to compare the results of non-invasive ABPM in a population of patients with essential hypertension who had never been treated, subdividing them based on the presence or absence of LVH in the transthoracic echocardiogram (LVMI, left ventricular mass index > 135 g/m2 in males and > 110 g/m2 in females). METHODS: Eighty hypertensive patients with mild or moderate hypertension underwent routine blood tests, a 24 h ABPM and a transthoracic echocardiogram. Based on the ABPMs, we analyzed average 24 h systolic and diastolic blood pressure (BP), average daytime (6 a.m.-10 p.m.) and nighttime (10 p.m.-6 a.m.) systolic and diastolic BP, average morning (6-12 a.m.) BP and the number of dipper or non-dipper patients. The echocardiographic study included the calculation of left ventricular mass using Devereux's formula according to the Penn convention, analysis of the patterns of left ventricular geometry and a study of left ventricular diastolic function. RESULTS: Thirty-five (43.7%) patients had LVH at the echocardiographic study. In 52 subjects, the clinical history showed at least one BP measurement > 140/90 mmHg in the year prior to our observation. The average age was 48 +/- 11, without any significant correlation to LVMI (r = 0.13). The magnitude of the S-wave in V1 and the R-wave in V5 and the magnitude of the tallest R-wave and S-wave in the electrocardiogram analysis had a significant correlation with LVMI (r = 0.23 and r = 0.26, respectively). The echocardiogram revealed a normal left ventricular geometry in 43.8% of hypertensive patients, concentric remodeling in 13.8%, concentric hypertrophy in 16.2% and eccentric hypertrophy in 26.2%. The isovolumic relaxation time (IVRT) and A-wave were significantly correlated with LVMI (r = 0.49 and r = 0.33, respectively). LVMI had a significant correlation with systolic BP at ABPM (24 h systolic BP r = 0.34; daytime systolic BP r = 0.35; nighttime systolic BP r = 0.28; 6-12 systolic BP r = 0.29) but not with diastolic BP. Dipper patients represented 76.3% of the population, without any difference in LVMI between dippers and non-dippers (p = 0.09). Dipper patients had a higher prevalence of normal left ventricles as compared with non-dippers (p < 0.0001). White-coat hypertension was observed in 7.5% of hypertensive patients. CONCLUSIONS: The prevalence of LVH in our population was high (43.7%) and some parameters related to diastolic left ventricular function (IVRT, A-wave) were correlated with LVMI. Systolic ambulatory BP was significantly correlated with LVMI, while diastolic BP was not.

Adult↗