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PubMed1999

Cross-sectional survey of intralymphocytic and serum elements in hypertensive patients.

OBJECTIVE: To investigate the distribution characteristics of some common and trace elements in both serum and lymphocyte in patients with essential hypertension and to analyse their possible role in the pathogenesis of hypertension. METHODS: A cross-sectional study was carried out in 102 hypertensive patients matched with equal number of normotensive subjects by sex, age, and hypertensive family history; all of them were randomly selected from the same community. Both intralymphocytic and serum concentrations of some relevant elements including Na+, K+, Ca2+, Mg2+, Zn2+, Cu2+ and P were measured for all studied subjects, using the inductively coupled plasma spectrometry (ICPS). RESULTS: 1. Both intralymphocytic and serum concentrations of Na+ (P = 0.009, 0.004 respectively), and Ca2+ (P = 0.001, 0.049 respectively) in hypertensive group were significantly higher than those in the normotensives. 2. Stepwise regression analysis disclosed that systolic and diastolic blood pressure had significant correlation with age, serum Na+/K+ ratio and intralymphocytic Ca2+, Mg2+ concentrations (P < 0.001 for both). 3. According to hypertensive family history, the method of multiple variance analysis had been employed for 4 subgroups and the results revealed that the concentrations of serum Ca2+ and lymphocytic Na+ were significantly higher in hypertensives with or without family history than in normotensives without family history. Furthermore, intralymphocytic Na+ concentration was significantly higher in normotensives with positive family history than that in normotensives without family history. CONCLUSION: The serum and intralymphocytic distribution characteristics of elements in hypertensive patients compared with normotensive controls suggested that there might exist certain defects of the ion-transporting system on cell membrane which might be genetically linked.

Adult↗
PubMed2005

[Postoperative pain management using subcutaneous fentanyl and ketamine after abdominal gynecologic surgery].

BACKGROUND: Subcutaneous opioid is one way of managing postoperative pain in patients undergoing anticoagulant therapy. We have evaluated the safety and the efficacy of postoperative pain management using subcutaneous fentanyl and ketamine after abdominal gynecologic surgery. METHODS: Written informed consent was obtained from 50 ASA physical status 1 or 2 female patients aged between 20 and 65. Patients were randomized to one of 5 groups. Group 1, 2 and 3 received 25, 35 and 50 microg x h(-1) subcutaneous fentanyl infusion, respectively. Group 4 received 25 microg x h(-1) fentanyl and 2 mg x h(-1) ketamine subcutaneously; group 5 received 25 microg x h(-1) fentanyl and 4 mg x h(-1) ketamine subcutaneously. General anesthesia was administered to all patients. Two hours after induction, subcutaneous infusion of fentanyl and ketamine was started in the patients and discontinued 24 hours after the operation. All patients were assessed twice, at 4 hours and at 24 hours after operation. Blood gas analysis was performed. Number of analgesic administration required during the 24 hours after operation was recorded. Groups 1, 2, 3 and groups 1, 4, 5 were evaluated as one group, respectively. Group differences were analyzed by variance analysis. Differences of analgesic administration were analyzed with Kruskal-Wallis test. RESULTS: As to anesthetic requirement during the 24 hours after operation, there were no significant differences among treatment groups. With respect to blood gas analysis, only individuals receiving subcutaneous 25 microg x h(-1) fentanyl and 4 mg x h(-1) ketamine maintained high PaO2 4 hours after the operation (P<0.05). CONCLUSIONS: We recommend administration of 25 microg x h(-1) fentanyl and 4 mg x h(-1) ketamine subcutaneously, which maintains high Pao2 and requires less analgesic.

Adult↗
PubMedDate not supplied

Morphometric analysis of the sacroiliac joint.

The sacroiliac (SI) joint is the point of articulation between the sacrum and the innominate bone of the pelvis. The anterior portion is synovial, and the posterosuperior portion is a typical syndesmosis. The SI joint may be affected by inflammatory or degenerative changes which include narrowing, minor sclerosis and erosion. Alterations in the anatomy of this joint may be involved in causing lower back pain. Radiodiagnosis of the width of the articular space is one of the tools utilized to evaluate the normal state of any joint. Scanty data is available on the morphometric characteristics of the SI joint. Therefore, the articular width space of the SI joint was measured to define its normal size in relation to age and sex. The study included 198 x-rays of the abdomen, in anteroposterior projection, of 112 males and 86 females (age range: 17 to 91 yrs). Individual films were divided into four classes according to age (< 50; 50-59; 60-69; > 70). The articular space of the SI joint is made up of a lateral and a medial part: the first representing the anterior articular space; the latter the posterior one. The anterior articular space of both the right and left joint, which was more easily visible and measurable was measured at the medium and inferior levels. Measurements were taken from the radiograms using a semiautomatic computerized system (Videoplan II, Image Analysis system-Kontron). The mean value of the articular space width a the medium and inferior levels, according to age group, was measured in both the males and females. The values obtained were studied using variance analysis. No significant differences were found in the mean values of the articular space width at the SI joint, when males and females were compared in relation to age. Moreover, the articular space width diminished with increasing the age. This fact was not always statistically significant.

Adolescent↗
PubMed2000

Polymorphic analysis of a pharmaceutical preparation by NIR spectroscopy.

A method for the characterization and determination of the crystalline from present in the amorphous miokamycin of a pharmaceutical preparation using near-infrared spectroscopy (NIRS) is proposed. The study leading to the development of the proposed method involved both qualitative (classification by residual variance analysis) and quantitative aspects (the determination of both total miokamycin and its crystalline form using multivariate calibration). Samples containing less than 5% of the total amount of miokamycin in its crystalline form can be accurately classified. Partial least-squares regression (PLSR) allows low contents of the crystalline form to be determined with absolute errors less than 1.5%, which is comparable to the limit of detection of the X-ray diffraction technique used as reference. Also, the total miokamycin content is determined by NIRS with errors less than 1%. The simplicity, expeditiousness and robustness of the proposed method make it an effective tool for determining both total and crystalline miokamycin in solid dosage forms.

Least-Squares Analysis↗
PubMed2003

Variance components linkage analysis for adjusted systolic blood pressure in the Framingham Heart Study.

We performed variance components linkage analysis in nuclear families from the Framingham Heart Study on nine phenotypes derived from systolic blood pressure (SBP). The phenotypes were the maximum and mean SBP, and SBP at age 40, each analyzed either uncorrected, or corrected using two subsets of epidemiological/clinical factors. Evidence for linkage to chromosome 8p was detected with all phenotypes except the uncorrected maximum SBP, suggesting this region harbors a gene contributing to variation in SBP.

Adult↗
PubMed2005

Cardiac dyssynchrony analysis using circumferential versus longitudinal strain: implications for assessing cardiac resynchronization.

BACKGROUND: QRS duration is commonly used to select heart failure patients for cardiac resynchronization therapy (CRT). However, not all patients respond to CRT, and recent data suggest that direct assessments of mechanical dyssynchrony may better predict chronic response. Echo-Doppler methods are being used increasingly, but these principally rely on longitudinal motion (epsilonll). It is unknown whether this analysis yields qualitative and/or quantitative results similar to those based on motion in the predominant muscle-fiber orientation (circumferential; epsiloncc). METHODS AND RESULTS: Both epsilonll and epsiloncc strains were calculated throughout the left ventricle from 3D MR-tagged images for the full cardiac cycle in dogs with cardiac failure and a left bundle conduction delay. Dyssynchrony was assessed from both temporal and regional strain variance analysis. CRT implemented by either biventricular (BiV) or left ventricular-only (LV) pacing enhanced systolic function similarly and correlated with improved dyssynchrony based on epsiloncc-based metrics. In contrast, longitudinal-based analyses revealed significant resynchronization with BiV but not LV for the overall cycle and correlated poorly with global functional benefit. Furthermore, unlike circumferential analysis, epsilonll-based indexes indicated resynchronization in diastole but much less in systole and had a lower dynamic range and higher intrasubject variance. CONCLUSIONS: Dyssynchrony assessed by longitudinal motion is less sensitive to dyssynchrony, follows different time courses than those from circumferential motion, and may manifest CRT benefit during specific cardiac phases depending on pacing mode. These results highlight potential limitations to epsilonll-based analyses and support further efforts to develop noninvasive synchrony measures based on circumferential deformation.

Animals↗
PubMed2003

Growth modeling of human mandibles using non-Euclidean metrics.

From a set of 31 three-dimensional computed tomography (CT) scans we model the temporal shape and size of the human mandible for analysis, simulation, and prediction purposes. Each anatomical structure is represented using 14851 semi-landmarks, and mapped into Procrustes tangent space. Exploratory subspace analyses are performed leading to linear models of mandible shape evolution in Procrustes space. The traditional variance analysis results in a one-dimensional growth model. However, working in a non-Euclidean metric results in a multimodal model with uncorrelated modes of biological variation related to independent component analysis. The applied non-Euclidean metric is governed by the correlation structure of the estimated noise in the data. The generative models are compared, and evaluated on the basis of a cross validation study. The new non-Euclidean analysis is completely data driven. It not only gives comparable results w.r.t. previous studies of the mean modeling error, but seems to better correlate to growth, and in addition provides the data analyst with alternative hypothesis of plausible shape evolution; hence aiding in the understanding of cranio-facial growth.

Child↗
PubMed2006

Morphometry and digital AgNOR analysis in cytological imprints of benign, borderline and malignant serous ovarian tumours.

AIM: The aim of the study was to determine values of a quantitative morphometry analysis of nuclear characteristics and argyrophilic nucleolar organizer regions (AgNORs) in differential cytodiagnosis of benign, atypically proliferating (borderline) and malignant serous ovarian tumours. METHODS: Cytological imprints of benign (n = 20), borderline (n = 19) and malignant (n = 20) ovarian serous tumours were analysed. A computerized, digital analysis was used to determine morphometric nuclear features, the number and characteristics of single AgNORs, cluster AgNORs, total AgNOR and AgNOR area/nucleus (relative area) ratio. According to their size AgNORs were classified in three categories. A one-way variance analysis and post hoc test (Scheffé) were used for statistical analysis. RESULTS: The morphometric nuclear analysis showed that benign, borderline and malignant serous ovarian tumours are statistically different (P < 0.001) according to the area and outline, the values being highest in malignant tumours and lowest in the borderline group. Digital analysis of AgNORs in benign, borderline and malignant groups showed that the total AgNOR number increases with progression of the lesion (meaning tumour malignancy) significantly (P < 0.001) between benign and malignant as well as between borderline and malignant serous ovarian tumours (P < 0.001). The progression of the lesion malignancy was accompanied by a significant (P < 0.001) progressive increase of the total and relative AgNOR area per nucleus. The AgNOR size increases from benign to malignant tumours and a statistically significant difference (P < 0.001) was observed in all three groups regarding small and large AgNORs. CONCLUSION: Combining different markers of morphometric nuclear characteristics and AgNOR values could improve differential cytodiagnosis of benign, borderline and malignant serous ovarian tumours.

Cystadenocarcinoma, Serous↗
PubMed2004

[The value of dynamic posturography (Equitest) in preparing an expert's report].

BACKGROUND: Expert appraisals of vestibular disorders and their effects on daily life are essentially based on an evaluation of the patient's subjectively described symptoms. The aim of the present study was to ascertain the extent to which dynamic posturography is able to assist in the preparation of expert's reports. MATERIAL AND METHODS: 60 patients underwent a survey of their balance impairment. Both a nystagmus analysis, with its objective criteria, and dynamic posturography were carried out. The investigation into reduction of fitness for work (MdE) made reference to the criteria specified in the table by STOLL. The data obtained were subjected to both correlation and variance analysis. RESULTS: Although the results of this analysis revealed no direct statistical dependency, they indicated a tendency for the composite values to be correlated with the nystagmus scores and/or the MdE values (when the nystagmus score and/or the MdE increases, the composite value decreases). CONCLUSIONS: The Equitest is, according to the available data, not able to replace the currently valid MdE scores. Nevertheless, it represents a means of providing objective data about the vestibulo-spinal reflex. The test also reveals any tendencies towards simulation and aggravation. In the context of a specific nystagmus analysis, the Equitest offers an additional means of providing an objective background to back up the more subjective assessment of MdE.

Adolescent↗
PubMed2006

Polyp measurement using CT colonography: agreement with colonoscopy and effect of viewing conditions on interobserver and intraobserver agreement.

OBJECTIVE: This article presents inter- and intraobserver agreement for estimates of polyp diameter using CT colonography, including the effects of different visualization displays and prior experience. MATERIALS AND METHODS: Four observers, three of whom had prior experience with CT colonography, estimated the maximum diameter of 48 polyps using three different visualization displays: 2D colonography window, 2D abdominal window, and 3D surface rendering. Each re-measured a subset of 10 polyps. Polyps measured 2 to 12 mm according to a colonoscopic reference. Inter- and intraobserver agreement and agreement with the reference measurement were determined using the Bland-Altman method, paired Student's t testing, analysis of variance, and analysis of covariance (ANCOVA), and by calculating the components of variance. RESULTS: CT measurements overestimated polyp diameter, a phenomenon found least using the 2D abdominal display. Generally, 95% limits of agreement encompassed different size categories for individual polyps: the widest spanned 14.6 mm (-4.6 mm to 10.0 mm) for an experienced observer using the 3D display. When using the 2D abdominal display, no significant difference was found between estimates and the reference value for the other two experienced observers (p = 0.83 and 0.23). All the observers' measurements were significantly different from the reference when using the 3D display (p < 0.001). The novice was significantly different from the experienced observers in some analyses. Inter- and intraobserver agreement were poorest for the 3D display. CONCLUSION: Measurement of polyp diameter from CT colonography is subject to variation contingent on the observer's experience and the viewing display used. Although 3D visualization display is commonly used for polyp detection, it should not be used for measurement.

Colonic Polyps↗
PubMedDate not supplied

[Results of treatment of non-traumatic cerebellar haemorrhages].

AIM: Presentation of experiences in the treatment and tentative determination of factors of prognostic importance which could be useful in the selection of appropriate treatment of patients with non-traumatic cerebellar haemorrhage. MATERIAL AND METHOD: 35 consecutive patients treated in the years 1987-1996 were analysed retrospectively. Their condition on admission was assessed using Glasgow Coma Scale and the treatment results were assessed using the Glasgow Outcome Scale at the time of discharge. All patients had CT which was repeated, as necessary, and in some cases angiography was done. Ten patients were treated surgically and 25 only conservatively (in six of them temporary external ventricular drainage was performed due to hydrocephalus). The analysis included the influence of localisation and volume of haemorrhage, presence of hydrocephalus, intraventricular extension of haemorrhage fourth ventricle and quadrigeminal cistern appearance on the state of the patients and on treatment results. Non-parametric tests: Mann-Whitney and variance analysis of Kruskal-Wallis were used for determination of statistical significance (p < 0.05). RESULTS: Six patients were in coma (4-7 GCS score), 6 had GCS score 8-12, 6 had GCS score 13-14, and 17 patients had no consciousness disturbances. Haematoma involved only cerebellar hemisphere in 21 cases, hemisphere and vermis in 12, cerebellum with brain stem extension in 2 cases. Haematoma volume was below 20 ml in 25 cases, over 20 ml in 5 cases, and in 5 case the volume could not have been determined. Hydrocephalus was present in 12 patients being related to CSF outflow block in 7 and to intraventricular haemorrhage in 5 cases. Intraventricular extension of haemorrhage occurred in 9 cases. Hydrocephalus presence (p = 0.005) and haematoma volume (p < 0.03) influenced significantly consciousness level on admission. In the surgically treated group 2 patients died and in 7 cases the result was satisfactory (GOS:MD + GR). In the group treated conservatively 4 patients died, 2 became disabled, and 19 left the hospital in good or very good condition (GOS:MD + GR). The total mortality was 17.2%, consciousness level on admission (p = 0.001), haematoma volume (p < 0.05), hydrocephalus presence (p < 0.008), intraventricular extension of haemorrhage (p < 0.008) had significant influence on treatment results. CONCLUSIONS: In the light of our experience it is suggested that patients in coma should be operated on for haematoma evacuation with or without temporary external ventricular drainage. In conscious patients with stable course of disease medical treatment can be considered.

Adult↗
PubMed2005

Risk aversion and uncertainty in cost-effectiveness analysis: the expected-utility, moment-generating function approach.

The availability of patient-level data from clinical trials has spurred a lot of interest in developing methods for quantifying and presenting uncertainty in cost-effectiveness analysis (CEA). Although the majority has focused on developing methods for using sample data to estimate a confidence interval for an incremental cost-effectiveness ratio (ICER), a small strand of the literature has emphasized the importance of incorporating risk preferences and the trade-off between the mean and the variance of returns to investment in health and medicine (mean-variance analysis). This paper shows how the exponential utility-moment-generating function approach is a natural extension to this branch of the literature for modelling choices from healthcare interventions with uncertain costs and effects. The paper assumes an exponential utility function, which implies constant absolute risk aversion, and is based on the fact that the expected value of this function results in a convenient expression that depends only on the moment-generating function of the random variables. The mean-variance approach is shown to be a special case of this more general framework. The paper characterizes the solution to the resource allocation problem using standard optimization techniques and derives the summary measure researchers need to estimate for each programme, when the assumption of risk neutrality does not hold, and compares it to the standard incremental cost-effectiveness ratio. The importance of choosing the correct distribution of costs and effects and the issues related to estimation of the parameters of the distribution are also discussed. An empirical example to illustrate the methods and concepts is provided.

Cost-Benefit Analysis↗
PubMed2005

Optimization of lactose utilization in deproteinated whey by Kluyveromyces marxianus using response surface methodology (RSM).

Kluyveromyces marxianus Y-8281 yeast culture was utilized for the biological treatment of deproteinated whey wastewater in a batch system. Removal of lactose was optimized by the utilization of response surface methodology, RSM. The empirical model developed through RSM in terms of effective operational factors of medium pH, temperature, lactose and ammonia concentrations was found adequate to describe the treatment of deproteinated whey. Through the analysis, medium pH and temperature were found to be the most significant factors and an increment in both had a positive effect on lactose utilization, while lactose and ammonia concentrations had the least weight within the ranges investigated. Based on contour plots and variance analysis, optimum operational conditions for maximizing lactose removal were found to be 31 degrees C, 45 g/L whey powder concentration, 4 g/L total ammonium salt concentration and medium pH 6. Under the optimum operating conditions determined, 95% lactose removal was achieved after an 18-h fermentation.

Ammonia↗
PubMed2001

Analysis of uncertainties in estimates of components of variance in multivariate ROC analysis.

RATIONALE AND OBJECTIVES: Solutions have previously been presented to the problem of estimating the components of variance in the general linear model used for multivariate receiver operating characteristic (ROC) analysis. The case where the variance components do not change across the modalities under comparison was first treated, followed by the case where they are permitted to change. No analysis of uncertainties in these estimates has been presented previously. MATERIALS AND METHODS: For the case where the variance components do not change across modalities, the "jackknife-after-bootstrap" resampling procedure can be used together with conventional linear propagation of variance to solve for the uncertainties in estimates of the components. For the case where the components are permitted to change across modalities, a slight elaboration of this procedure is presented. RESULTS: The approach was validated by Monte Carlo simulations, where uncertainties in estimates of the variance components calculated by the jackknife-after-bootstrap procedure were found to converge in the mean to the Monte Carlo results over many independent trials. The method is exemplified with data from a study of readers-with and without the aid of a computer-assist modality-given the task of discriminating benign from malignant masses in mammography. CONCLUSION: The present approach is relevant to a broad class of problems where estimates of multiple contributions to the variance observed in ROC assessment of diagnostic modalities are desired, in particular, for the assessment of multiple-reader studies of computer-aided diagnosis in radiology where the variance components may change across reading modalities (eg, unaided vs computer-aided reading).

Analysis of Variance↗
PubMed1986

Numerical evaluation of changes in the cytoplasmic microtubule complex of C3H mouse cells by optical diffractometry and of changes in cell shape by Fourier analysis.

MO mouse cells in culture on glass were treated with taxol, or nocodazole, or incubated at 4 degrees C to alter their cytoplasmic microtubule complex (CMTC). From each treated group and from an untreated group, 30 cells stained with an antiserum against tubulin, were photographed under the photomicroscope, and negatives were analysed by optical diffractometry. Differences between groups of cells were tested by variance analysis. Phase-contrast micrographs of the same cells were used for Fourier analysis of cell shape. Both types of analyses provided numerical objective data about changes in the CMTC and in cell shape that were typical for the kind of treatment. We conclude that optical diffractometry of immunostained cells and Fourier analysis of cell shape are complementary to photomicroscopy for the study of the CMTC in cell populations cultured on an artificial substrate.

Alkaloids↗
PubMed1989

Estimation of pubic age among Chinese Han people by means of multiple stepwise progressive analysis.

This paper sets up an equation for estimating male and female ages separately by means of a computer with mathematical model of multiple stepwise progressive regression on data of 454 pairs of pubes of Chinese Han people in Northeast China. The equation upgrades a standardization of pubic age estimation to quantification. The correlation coefficient of the equation is 0.9906-0.9912; S.D. is 1.56-1.97; variance analysis F greater than 001 and p less than 0.01. By a blindfold test of 43 pairs of pubic bones with birthdate, the rate of concordance is 76-82% for +/- S.D. and 92-96% for +/- 2S.D.

Adolescent↗
PubMed2005

Inhibition of inducible nitric oxide synthase promotes recovery of motor function in rats after sciatic nerve ischemia and reperfusion.

PURPOSE: To investigate the effects of inhibition of inducible nitric oxide synthase (iNOS) on the recovery of motor function in the rat sciatic nerve after ischemia and reperfusion injury. METHODS: A 10-mm segment of the sciatic nerve from 169 rats had 2 hours of ischemia followed by up to 42 days of reperfusion. The animals were divided into 2 groups that received either iNOS inhibitor 1400W or the same volume of sterile water subcutaneously. A walking track test was used to evaluate the motor functional recovery during reperfusion. Statistical analysis was performed for the measurements of the sciatic functional index (SFI) by using 2-way analysis of variance; 1-way analysis of variance was used for the post hoc analysis of specific values at each time point of the SFI measurement. RESULTS: 1400W-treated rats had earlier motor functional recovery than controls, with a significantly improved SFI between days 11 and 28. Histology showed less axonal degeneration and earlier regeneration of nerve fibers in the 1400W group than in the controls. Inducible NOS messenger RNA and protein were up-regulated during the first 3 days of reperfusion but there was a down-regulation of neuronal NOS and up-regulation of endothelial NOS in control animals. 1400W treatment attenuated the increase of iNOS but had no effect on neuronal NOS and endothelial NOS. CONCLUSIONS: Our results indicate that early inhibition of iNOS appears to be critical for reducing or preventing ischemia and reperfusion injury.

Analysis of Variance↗