Pearson's Correlation Test (pearson + correlation_test)

Distribution by Scientific Domains


Selected Abstracts


Serum iron and copper status and oxidative stress in severe and mild preeclampsia

CELL BIOCHEMISTRY AND FUNCTION, Issue 3 2006
Zehra Serdar
Abstract Our aim was to investigate parameters of iron and copper status and oxidative stress and antioxidant function in women with healthy pregnancy, mild and severe preeclampsia with a view to exploring the possible contribution of these parameters to the aetiology. Thirty healthy, 30 mild preeclamptic and 30 severe preeclamptic pregnant women were included. Serum and placental lipid peroxides, and serum vitamin E and total carotene levels were measured by colorimetric assay. Cholesterol, copper, iron, total iron binding capacity (TIBC), ceruloplasmin and transferrin concentrations were measured by commercially available procedures. Data were analysed statistically using one-way analysis of variance and Pearson correlation test. Logistic regression procedures were used to calculate odds ratios. Lipid peroxides in serum and placental tissue, and iron, copper and ceruloplasmin levels in serum were significantly increased, and transferrin, TIBC, vitamin E/total cholesterol and total carotene/total cholesterol ratios in serum were significantly decreased especially in women with severe preeclampsia. Significant correlations were detected between serum iron and lipid peroxidesin serum and placental tissue and between serum iron and vitamin E/total cholesterol in severe preeclamptic pregnancy. Furthermore, there were significant correlations between serum malondialdehyde and ceruloplasmin and vitamin E/total cholesterol in women with severe preeclampsia, and changes in serum and placental lipid peroxides and serumiron concentrations were significantly associated with preeclampsia. In conclusion, ischaemic placental tissue may be a primary source of potentially toxic iron in preeclampsia and the released iron species may contribute to the aetiology and would exacerbatelipid peroxidation and endothelial cell injury, which may be abated by antioxidant supplementation. Copyright © 2005 John Wiley & Sons, Ltd. [source]


Evaluation of maximal bite force in temporomandibular disorders patients

JOURNAL OF ORAL REHABILITATION, Issue 8 2006
E. M. KOGAWA
summary, The aim of this study was to evaluate the maximum bite force in temporomandibular disorders (TMD) patients. Two hundred women were equally divided into four groups: myogenic TMD, articular TMD, mixed TMD and control. The maximum bite force was measured in the first molar area, on both sides, in two sessions, using an IDDK (Kratos) Model digital dynamometer, adapted to oral conditions. Three-way anova, Tukey and Pearson correlation tests were used for the statistical analysis. The level of statistical significance was given when P , 0·05. The maximal bite force values were significantly higher in the control group than in the experimental ones (P = 0·00), with no significant differences between sides. Higher values were obtained in the second session (P = 0·001). Indeed, moderate negative correlation was found between age and bite force, when articular, mixed groups and all groups together were evaluated. A moderate negative correlation was also detected between TMD severity and the maximal bite force values for myogenic, mixed and all groups together. Authors concluded that the presence of masticatory muscle pain and/or TMJ inflammation can play a role in maximum bite force. The mechanisms involved in this process, however, are not well understood and deserve further investigation. [source]


A quantitative approach to probe the dependence and correlation of food-effect with aqueous solubility, dose/solubility ratio, and partition coefficient (Log P) for orally active drugs administered as immediate-release formulations

DRUG DEVELOPMENT RESEARCH, Issue 2 2005
Brahma N. Singh
Abstract The purpose of the present review was to systematically evaluate if aqueous solubility, dose/solubility ratio, and partition coefficient (Log P) could be used as useful parameters to quantitatively probe the dependence and correlation of in vivo food effects with these physicochemical properties of orally active drugs administered as immediate-release (IR) formulations. Mean AUC data obtained under fasted and fed states of over 100 structurally diverse orally active drugs with different physicochemical properties were obtained from the primary literature. Correlations of AUC ratio (Fed/Fasted) with aqueous solubility, dose/solubility ratio, and Log P were derived and statistically evaluated by Pearson's correlation test (two-tailed). A negative correlation was obtained between the logarithm of the aqueous solubility and the AUC ratio (r=,0.5982, N=93), whereas a positive correlation existed between AUC ratio and Log P (r=0.5147, N=110) and between AUC ratio and dose/solubility ratio (r=0.5511, N=87). All these correlations were significant (P<0.0001). Based on this study, the estimated range within which a drug is not expected to be significantly affected by food falls between 0.148,89.39 mg/ml for aqueous solubility and between 0.23,624 ml for the dose:solubility ratio. The corresponding range of Log P for expecting a lack of food-effect lies between ,1.13 and 2.98. Quantitatively, the effect of food was most pronounced for lipophilic, poorly water-soluble drugs (with only a few exceptions), irrespective of whether the drug is acidic, basic, or neutral. It is concluded that aqueous solubility, dose/solubility ratio, and partition coefficient can be used as useful parameters to probe the dependence and correlation of food-effect with these physicochemical parameters for immediate-release formulations. Drug Dev. Res. 65:55,75, 2005. © 2005 Wiley-Liss, Inc. [source]


Color vision and macular recovery time in epileptic adolescents treated with valproate and carbamazepine

EUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2006
A. Verrotti
Visual dysfunction has been reported in patients diagnosed with epilepsy. Some of these visual disturbances may be attributable to either the disease process, or the anticonvulsant therapy prescribed to control the seizures. The aims of our study were to evaluate whether color vision and macular function are impaired in epileptic adolescents, to study if the monotherapy with valproic acid (VPA) and carbamazepine (CBZ) can affect color vision and macular function and to determine the possible relationship between color vision, retinal function and antiepileptic drugs (AEDs) dosage and their serum concentrations. We examined 45 (16 male and 29 female, mean age ± SD, 15.71 ± 2.01 years) Caucasian epileptic patients suffering from various types of cryptogenic epilepsy before the beginning of therapy and after 1 year of VPA or CBZ monotherapy and 40 sex- and age-matched healthy controls. Color vision was assessed by Farnsworth Munsell (FM) 100-hue test and total error score (TES) was evaluated. This test consists of colored caps: the testee has to arrange the caps according to their colors macular function was assessed by nyctometry evaluating initial recovery time (IRT) and summation method (SM). This test evaluates visual acuity after a period of intense illumination of macula. Analysis of variance was used to evaluate the difference between controls and patients; moreover, Pearson's correlation test have been performed. Before the beginning of therapy, there were no differences in color vision and macular function between controls and epileptic patients. After 1 year, the patients, treated with VPA or CBZ, showed a deficit in FM 100-hue test. At nyctometry, all patients showed no significant variation of macular function between baseline evaluation and second evaluation at end of the follow-up. Our study demonstrates that, in our group of epileptic patients, epilepsy per se does not affect color vision and retinal function. In contrast, after 1 years of therapy with VPA and CBZ these patients showed a deficit in FM 100-hue test although nyctometry evaluation continued to be normal allowing to exclude an impairment in macular function. Further investigations are required to determine the pathophysiological alteration(s) that are at the basis of color perception defects. [source]


Difference in non-weight-bearing effects on bone mineral density between trunk and peripheral fat mass in women with polycystic ovary syndrome

JOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 2 2010
Yumi Yanazume
Abstract Aim:, To investigate the difference in non-weight-bearing effects on bone mineral density (BMD) between trunk and peripheral fat mass in women with polycystic ovary syndrome (PCOS). Methods:, Subjects were 123 amenorrheic PCOS women with right side dominance. Age, height, body weight, and body mass index were recorded. Trunk, peripheral (extremities), trunk,leg fat ratio as an index of body fat distribution, left arm (non-weight-bearing site) lean mass and BMD were measured by dual-energy X-ray absorptiometry. Serum testosterone and estradiol levels were measured. Relationships of BMD with trunk, peripheral fat mass, and sex hormones levels were investigated. Results:, Trunk fat mass amount was 9.8 ± 6.7 kg and was lower than the peripheral fat mass amount (12.2 ± 4.4 kg, P < 0.01). On Pearson's correlation test, trunk fat mass and left arm lean mass were positively correlated with arm BMD (r = 0.359, P < 0.001 and r = 0.501, P < 0.0001, respectively), while peripheral fat mass and serum testosterone levels were not correlated with BMD (r = 0.083 and 0.114, respectively, NS). On multiple regression analysis, trunk fat mass was positively correlated with BMD (t -value = 3.465; P < 0.001), independent of age and height. However, this relationship disappeared after additionally adjusting for left arm lean mass. Conclusion:, Trunk fat mass, despite the smaller amount, is more associated with arm BMD than peripheral fat mass is through its non-weight-bearing effects. [source]


External cephalic version induced fetal cerebral and umbilical blood flow changes are related to the amount of pressure exerted

BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 5 2004
Tak Yeung Leung
Objective To correlate the applied pressure during external cephalic version with the changes in fetal middle cerebral arterial and umbilical arterial flow before and after the procedure. Design A prospective observational study over a two-year period. Setting External cephalic version was performed in a university hospital. Population Sixty-nine women with singleton breech-presenting pregnancy at or above 36 weeks of gestation undergoing external cephalic version. Methods During external cephalic version, the operator wore a pair of pressure-sensing gloves which had thin piezo-resistive sensors positioned on the palmar surface. During each version procedure, real-time pressure readings were recorded from all sensors, and then analysed with a computer program. The amount of pressure applied over time was presented by pressure,time integral. The pulsatility indices of both fetal middle cerebral artery and umbilical artery before and after external cephalic version were measured. The changes of pulsatility indices of both middle cerebral artery and umbilical artery were presented as a ratio of the post-external cephalic version pulsatility indices to pre-external cephalic version pulsatility indices, denoted by middle cerebral artery pulsatility index ratio and umbilical artery pulsatility index ratio, respectively. The statistical correlation between pressure,time integral and middle cerebral artery pulsatility index ratio and umbilical artery pulsatility index ratio are analysed using Pearson's correlation test. Main outcome measures Changes in pulsatility indices of fetal middle cerebral and umbilical arteries and fetal heart rate after external cephalic version. Results The overall success rate of external cephalic version was 77%. There was a significant negative correlation between pressure,time integral and both middle cerebral artery pulsatility index ratio (P= 0.001) and umbilical artery pulsatility index ratio (P= 0.012). When women were categorised according to placental site, pressure,time integral was negatively correlated with middle cerebral artery pulsatility index ratio only when the placenta was posteriorly located (P= 0.003), and with umbilical artery pulsatility index ratio only when the placenta was laterally located (P= 0.03). Conclusions The greater the force applied during external cephalic version, the greater the reduction in pulsatility indices of middle cerebral artery and umbilical artery, indicating an increase in blood flow through these arteries. The increase in cerebral blood flow after external cephalic version is more prominent when the placenta is lying posteriorly, while the increase in umbilical flow is more prominent when the placenta is lying laterally. These findings suggest that the vascular changes probably represent a direct effect of force exerted on the fetal head and the placenta. [source]


Evaluation of anterior segment parameter changes using the Pentacam after uneventful phacoemulsification

ACTA OPHTHALMOLOGICA, Issue 5 2010
Selim Doganay
Abstract. Purpose:, This study set out to evaluate the influences of uneventful phacoemulsification on the anterior segment parameters obtained with the Pentacam rotating Scheimpflug camera and intraocular pressure (IOP). Methods:, A total of 42 eyes of 34 patients (26 men, eight women) were evaluated preoperatively, and at 1, 3 and 6 months postoperatively with the Pentacam. Intraocular pressure was measured with the Goldmann applanation tonometer. The non-parametric paired t -test was used to compare preoperative and 1-, 3- and 6-month postoperative measurements of anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA) width, central corneal thickness (CCT), the central 3-, 5- and 7-mm corneal volume (CV), pupil size, and IOP. Pearson's correlation test was used to evaluate the relationships between IOP and ACD, ACV and ACA width. Results:, The differences between ACD, ACV, ACA and IOP values taken preoperatively and those taken postoperatively at 1, 3 and 6 months were statistically significant (p < 0.05). The differences between CCT, central 3-, 5- and 7-mm CV, and pupil size measurements taken preoperatively and those taken postoperatively at 1, 3 and 6 months were not statistically significant (p > 0.05). The decrease in IOP was not correlated with the changes in ACD, ACV and ACA (p > 0.05). Conclusions:, Uneventful phacoemulsification significantly reduced IOP, increased ACD and ACV, and widened the ACA. However, alterations in CV, CCT and pupil size values were not statistically significant. Alterations in ACD, ACV, ACA and IOP remain stable after the first month of surgery. [source]


Comparison of anterior chamber depth measurements taken with the Pentacam, Orbscan IIz and IOLMaster in myopic and emmetropic eyes

ACTA OPHTHALMOLOGICA, Issue 4 2009
Canan Asli Utine
Abstract. Purpose:, This study determined to assess the degree of agreement between anterior chamber depth (ACD) measurements obtained using three different devices and to analyse the relationship between ACD and spherical equivalent (SE) refraction. Methods:, In this cross-sectional study, 42 eyes of 42 patients with a mean SE of , 4.69 ± 4.61 D (range 0.00 D to , 14.88 D) were analysed. Measurements of ACD between the corneal epithelium and the anterior surface of the crystalline lens, obtained using the Pentacam, Orbscan IIz and IOLMaster, were compared. The relationships between SE and ACD measurements obtained with different devices were also investigated. The results were analysed using Bland,Altman analyses, single-sample t -test and Pearson's correlation test. Results:, Orbscan ACD measurements were an average of 0.05 mm less than Pentacam measurements (p = 0.01). IOLMaster measurements were an average of 0.06 mm less than Orbscan measurements (p < 0.001). None of the ACD values measured by any of the devices were correlated with increasing SE (p > 0.05 for all). There was a weak positive correlation between SE and the difference in ACD measurements with Pentacam and Orbscan (p = 0.04); however, the differences between Pentacam and IOLMaster ACD measurements and Orbscan and IOLMaster ACD measurements seemed to be independent of SE (p = 0.17 and p = 0.54, respectively). Conclusions:, The ACD in clinically normal eyes is measured differently by various non-ultrasonic devices. However, the observed mean error between these modalities is too small to create any noticeable difference in refractive outcome. No significant relationship was found between SE and ACD measurements obtained by Pentacam, Orbscan or IOLMaster. [source]


Intraocular pressure measurement in patients with previous LASIK surgery using pressure phosphene tonometer

CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 2 2005
Arthur CK Cheng MRCS
Abstract Purpose:,To compare intraocular pressure (IOP) assessment in post-LASIK patients using non-contact tonometry, pressure phosphene tonometry and applanation tonometry. Methods:,Sixty-two consecutive LASIK patients were analysed preoperatively and postoperatively with non-contact, pressure phosphene and applanation tonometry. Comparisons among these values were assessed with paired sample Student t -test, Pearson's correlation test and Bland,Altman plotting. Results:,There was no significant difference for preoperative IOP measurement between non-contact, pressure phosphene and applanation tonometry. The mean ±SD difference between the preoperative non-contact tonometry and postoperative pressure phosphene tonometry IOP measurements was 0.80 ± 2.77 mmHg (P < 0.01). Postoperative applanation tonometry significantly underestimated IOP measurement by 5.45 ± 2.96 mmHg (P < 0.001) and postoperative non-contact tonometry significantly underestimated IOP measurement by 9.96 ± 2.25 mmHg (P < 0.001). Conclusion:,Pressure phosphene tonometry may provide an alternative method for the assessment of IOP in post-LASIK patients. [source]