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PubMed1996

Analysis of molecular variance (AMOVA) of Y-chromosome-specific microsatellites in two closely related human populations.

The analysis of seven Y-chromosome-specific microsatellite loci revealed a high level of polymorphism in two closely related human populations (Dutch, n = 89, and German, n = 70). Four of these loci were found to generate at least 77 different haplotypes, only 15 of which were shared by the two populations. These results demonstrate that highly informative PCR-based DNA typing of the Y chromosome is now feasible. Assuming a stepwise mutation model, a network comprising all minimum spanning evolutionary trees connecting the haplotypes was constructed. Analysis of molecular variance based upon this network indicated that the within-population heterogeneity with respect to haplotype descent was significantly smaller than the between-population heterogeneity, suggesting that males were more closely related to males from their own population as opposed to males from the other population. These findings suggest that Y-chromosomal microsatellites might be very useful not only for forensic purposes but also in association studies of multifactorial traits, allowing the characterization of the level of genetic distinctiveness of supposedly inbred or isolated populations and discrimination even between closely related populations.

Analysis of Variance↗
PubMed2000

Measurements of temporal aspects of gait obtained with a multimemory stopwatch in persons with gait impairments.

STUDY DESIGN: Repeated measures of 14 temporal factors of gait obtained with a multimemory stopwatch from a variety of subjects with locomotor impairments. OBJECTIVES: To estimate the intratester and intertester reliability of 14 temporal factors of gait by using a multimemory stopwatch; to compare novice and expert clinicians at mastery of making these temporal measurements. BACKGROUND: Temporal gait measures are useful for describing the effectiveness of treatment interventions in patients with locomotor impairments. METHODS AND MEASURES: Eleven adult subjects (mean age, 48.4 years; SD, 5.7 years), 10 with locomotor impairments and 1 elderly adult, ambulated along a 6-m walkway 3 times at a self-selected walking speed. The subjects were videotaped from the side as they walked. Four physical therapists independently analyzed the videotapes on 2 occasions; 2 examiners were recent graduates, and 2 others had 23 years of clinical experience. Intraclass correlation coefficients were used to estimate intratester reliability. A component of variance analysis quantified the sources of variation. RESULTS: Intraclass correlation coefficients for each of the 14 variables varied from 0.88 to 0.98. The major contributor to variance was subject, followed by trial, error, and tester; the tester factor generally contributed less than 1% to the total variance. CONCLUSIONS: Reliable measurements of the temporal aspects of gait can be made by using a multimemory stopwatch and videotape in a clinical setting on patients with various locomotor problems. Our data suggest that measurements obtained by more experienced physical therapists were no more reliable than those made by recent graduates.

Adolescent↗
PubMedDate not supplied

[Atheroma plaque of the carotid bifurcation: how to identify an "active" lesion?].

UNLABELLED: The identification of carotid atheromatous plaques associated to a higher neurologic risk may be important in therapeutic decision making for asymptomatic patients and symptomatic patients with 50%-70% stenosis. The introduction of high-definition ultrasonography (HDU) and computer-assisted image analysis provides the possibility of a standard, objective and detailed characterization of the structure of the carotid plaque. The aim of this study is to analyse the relationship between the ultrasonographic characteristics of a group of plaques and the risk of associated cerebrovascular events and cerebral infarction. MATERIAL: One hundred carotid bifurcation plaques (in 68 patients) were studied for the presence of ipsilateral cerebrovascular events. In 61 patients (87 plaques), a correlation with CT scan for the presence of cerebral infarction was possible. METHOD: The lesions were studied by HDU (ATL-HDI 3000) and digitalized for computer-assisted standardization of the image. The analysis included the appreciation of the histogram of the image gray-scale pixel distribution by use of commercial software Adobe Photoshop 3.0. The parameters analysed for global echogenicity were the median of the histogram and the percentage of percentile 40 hypoechogenic pixels (40). Statistical analysis was made with STATA 4.0 software with categorical variables analysed by chi-square and Fisher's exact test and continuous variables analysed by variance analysis and Student's t test. RESULTS: Thirty eight (38%) plaques were symptomatic and 34 (39.1%) were associated to cerebral infarction. The degree of stenosis was > 70% in 51%; between 50 and 69% in 27% and < 50% in 22%. The mean of the median and P40 values was 33.9 and 60.3% in the symptomatic and 46.8 (p = 0.005) and 46.6% (p = 0.001) in the asymptomatic plaques respectively. In the plaques associated to cerebral infarction, it was 32.7 and 61.6% respectively, and in the ones with negative CT scan, it was 44.6 (p = 0.005) and 48.1% (p = 0.002). The mean of the median in the plaques vs. degree of stenosis was: > 70%--33.3; 50-69%--45.1; < 49%--57.7 (p < 0.001). In the series the cut-off point for the median value was 32 and for P40 it was 43 (for any degree of stenosis): G1--plaques < 32 (echolucent); G2--plaques > 32 (echogenic). In G1 symptoms occurred in 60% of the plaques and in 26% of the plaques in G2 (p = 0.0001). CT scan was positive in 66% of the echolucent plaques and in 25% of the echogenic plaques (p = 0.0238). CONCLUSION: 1. The more echolucent plaques are associated with a significantly higher neurological risk. 2. The plaques associated with higher degrees of stenosis are more echolucent. 3. The use of a standard and objective methodology in the analysis of the echographic structure of carotid plaques is important and limits the known intra and inter-observer variability of subjective appreciation.

Adult↗
PubMed2000

Molecular and functional properties of synaptically activated NMDA receptors in neonatal motoneurons in rat spinal cord slices.

The functional properties of N-methyl-D-aspartate (NMDA) receptor-mediated excitatory postsynaptic currents (EPSC) were studied in fluorescence-labelled motoneurons in thin spinal cord slices. The deactivation of NMDA receptor EPSCs in motoneurons voltage-clamped at +40 mV was independent of intensity or location of stimulation and of postnatal age [taufast = 28.5 +/- 4.6 ms (63.6 +/- 8.8%) and tauslow = 165.6 +/- 49.6 ms]. In the presence of 1 mM Mg2+ the amplitude of NMDA receptor EPSCs was voltage-dependent. Boltzmann analysis of the relationship between peak NMDA receptor EPSC amplitude and membrane potential suggested an apparent Kd of Mg2+ (at 0 mV) of 0.87 mM. Nonstationary variance analysis of NMDA receptor EPSCs gave an estimated single-channel conductance of 59 +/- 14 pS. Direct measurement of the NMDA receptor channel openings in outside-out patches isolated from motoneurons indicated the presence of single-channel conductance levels of 21.8 +/- 2.8 pS, 37. 1 +/- 3.2 pS, 49.6 +/- 5.1 pS and 69.6 +/- 4.2 pS. Single-cell RT-PCR analysis of mRNA revealed that NR1, NR2A-D and NR3A transcripts were expressed in motoneurons. These results suggest that specific assembly of NMDA receptor subunits in motoneurons determines the functional and pharmacological properties of the receptors in these cells.

6-Cyano-7-nitroquinoxaline-2,3-dione↗
PubMed1986

Analyzing the compositional changes in receivables.

A technique is proposed that applies variance analysis to the aged trial balance to break down the total change in reserve requirement, from one balance sheet date to the next, into a volume variance, a composition variance, and a rate variance. This breakdown allows the accountant or auditor to focus on compositional changes in the trial balance that contribute to otherwise irreconcilable changes in the provision requirement. An assessment of the reasons behind these compositional changes may result in adjustments to the reservation rates or to the provision amount to help bring the asset valuation into line with the income statement adjustments to revenue.

Accounting↗
PubMed1976

Relationship between auditory-visual integration, reading readiness, and conceptual tempo.

A modified downward extension of Birch and Belmont's auditory-visual integration test was correlated with the Metropolitan Readiness Test for 82 middle class kindergarten children. From this same sample the test performances of an equal numer (n = 11) of impulsive females, impulsive males, reflective females, and reflective males were compared with use of a 2 X 2 analysis of variance. An analysis of convariance was employed to further examine test performance. Metropolitan scores were equated for Verbal IQ; for auditory-visual integration, test response time and Verbal IQ were individually held constant. Auditory-visual integration variance accounted for 29% of Metropolitan variance. Reflectives performed significantly better than impulsives on the auditory-visual integration test with or without response time or WPPSI Verbal IQ held constant; they performed significantly better than impulsives on the Metropolitan, but this did not maintain when scores were equated for WPPSI Verbal IQ.

Analysis of Variance↗
PubMed1989

Long-acting propranolol in migraine prophylaxis: results of a double-blind, placebo-controlled study.

The efficacy and safety of long-acting propranolol (LA.P), 160 mg once-daily, in the prophylactic treatment of migraine have been tested against placebo in a multicentric, double-blind, randomized study. The two groups are compared in a parallel manner over a treatment period of 12 weeks, following a 4-week placebo run-in period. Fifty-five of the 74 patients who entered the trial were included at the end of the run-in period. Forty-one patients completed the study. None of the 14 patients who withdrew from the study did so because of side effects. The statistical analysis was done according to the "intention to treat" principle. LA.P was significantly more effective than placebo in reducing the frequency of migraine attacks (p = 0.01 by variance analysis). LA.P reduced the average number of monthly crises by 48% on day 84. There was a slight but significant reduction of the systolic blood pressure and heart rate in the erect position, but there was no significant difference between LA.P and placebo regarding either the number of complaints or the number of side effects elicited out of a 17-item questionnaire. None of the observed side effects led to a withdrawal from treatment.

Adult↗
PubMed2003

Adhesion molecules in gonarthrosis and knee prosthesis aseptic loosening follow-up: possible therapeutic implications.

The involvement of the synovium is common in phlogistic processes of various joint diseases. Apart from synoviocytes and the other cells in the synovial tissue, circulating cells recruited from peripheral blood also participate in the phlogistic process. The increased expression of adhesion molecules on both circulating and endothelial cell surface may further this recruitment. We studied 15 patients affected by serious gonarthrosis requiring a prosthetic implant (GPI) and 7 with knee prosthesis aseptic loosening (KPL) to evaluate adhesion molecule expression and phlogistic infiltration in the synovium using immunohistochemistry and microscopic analysis. As control we studied 10 subjects affected by degenerative meniscopathies undergoing a selective arthroscopic surgical meniscectomy. Analysis with Kruskal-Wallis test showed no statistical significant differences in the expression of CD54, CD11a, CD11b and CD18 in three groups examined. The model of variance analysis (Friedman test), showed that CD54 expression is greater in patients with GPI and KPL in comparison with the other molecules. Adhesion molecules and their functions are important in arthropathies not only because their evaluation can allow us to identify the degree of inflammation and to predict its evolution, but also because pharmacological control of their expression could have important therapeutic implications.

Adult↗
PubMedDate not supplied

[Beta-blockers and migraine. Efficacy of time-release propranolol versus placebo].

The efficacy and safety of long-acting propranolol (LA.P) 160 mg once-daily in the prophylactic treatment of migraine were tested against placebo in a multicentric, double-blind, randomized study comparing the two groups in a parallel manner over a treatment period of 12 weeks, and following a 4 week-placebo run-in period. Fifty-five out of the 74 patients who entered the trial included at the end of the run-in period. Forty-one patients completed the study. Out of the 14 patients who withdrew from the study, none discontinued because of side-effects. The statistical analysis was done according to the "intention to treat" principle. LA.P was significantly more efficient than placebo in reducing the frequency of migraine attacks (p = 0.01 by variance analysis). LA.P reduced the average number of monthly crises by 48% on day 84. There was a slight but significant reduction of the systolic blood pressure and heart rate in the erect position. There was no significant difference between LA.P and placebo regarding either the number of complaints or the number of side-effects elicited out of an 17 item questionnaire. None of the observed side effects led to a withdrawal of treatment.

Adult↗
PubMed2003

[Biochemical parameters of blood and nutrition model of the elderly].

The aim of the study was the analysis of the blood biochemical indices values depending on the nutrition model. The research was carried out in 1999 year among at random chosen 188 people 75-80 years old residing the neighbourhood of Olsztyn. The nutrients intake was assessed by means of the 24-hour recall method and, after having included loses, was compared with the recommended intake on the safe level. The blood biochemical indices were defined in the Central Analytical Laboratory of the City Hospital in Olsztyn according to the standard procedure. The analysis was assessed by Statistica v.6.0 program with the application of the factor and cluster analysis. Three nutrition models were separated: "low nutritive", "dairy" and "meat-vegetable-fruit". The comparison and distribution of the mean blood biochemical value was carried out using the variance analysis and the chi 2 test at p < or = 0.05. No differentiation in the levels of most blood biochemical indices depended on women and men nutrition model has been confirmed. Among 1-16% of women and 12-28% of men too low haematocrit and haemoglobin values were stated, among 34% of women and 23% of men--too low albumin values, and among 24% of women and 11% of men too high glucose values in the blood were found. About 32% of women and 35% of men showed too low HDL cholesterol ratio to total cholesterol content. Too low value of the vitamin B12 in the blood was revealed for 6% of women and 5% of men, and folic acid among 26% and 37%, for women and men, respectively. Regardless of realized nutrition model the significant percentage of elderly people has been characterized with the increased risk of cardiovascular diseases, diabetes or anaemia.

Aged↗
PubMed2007

Effects of diclofenac and tenoxicam on distraction osteogenesis.

INTRODUCTION: In the management of bone defects, pseudoarthrosis, deformities, chronic osteomyelitis and in extremity lengthening procedures, the technique of distraction osteogenesis (DO) has been frequently used. In this experimental animal study, the effects of two non-steroidal anti-inflammatory drugs, i.e., diclofenac and tenoxicam, on the outcomes of distraction osteogenesis are investigated. MATERIALS AND METHODS: In this study, 30 mature New Zealand-type male rabbits (2.5-4.5 kg) were used. The rabbits were randomized into three groups, each consisting of ten animals. Under optimal operating conditions, a pre-reconstructed circular external fixator was applied on the right tibias of rabbits, and osteotomy was performed with a Gigli saw just below the tibial tuberosity. After seven postoperative days, distraction was initiated at a rhythm of 2 x 0.5 mm/day. During the 10 days of distraction, adjunctive therapy was not instituted for group I (control group). For 10 days, group II received i.m. diclofenac sodium (0.5 mg/kg per day) and group III was treated with tenoxicam (8 mg/kg per day i.m.). At the end of 3 weeks postoperatively, five rabbits from each group were killed for histologic examinations. The remaining rabbits were killed at the end of eight postoperative weeks for biomechanical and histological analysis. Besides, radiological examinations were performed at the end of 3, 6 and 8 weeks postoperatively for the radiologic evaluation of calluses. For statistical evaluations between groups, Kruskal-Wallis variance analysis, and for intergroup assessments, Mann-Whitney test were performed. RESULTS: For radiological evaluations, the scoring system developed by Lane and Sandhu, and for histopathological assessments, the grading system of Huddlestone et al. were used. Biomechanical tests were realized using torsional loading. During the first 3 weeks, the groups did not differ much in the radiological parameters. However, in the diclofenac group and in especially the tenoxicam group, the histological scores were lower than in the control group. Radiological images obtained at the end of 6 weeks demonstrated inadequate consolidation in the diclofenac and tenoxicam groups when compared with the control group. At the end of 8 weeks postoperatively, in consideration of biomechanical, radiological and histological tests, significantly worse regenerates were obtained in the diclofenac and tenoxicam groups. CONCLUSIONS: During the distraction osteogenesis period, diclofenac and tenoxicam affected the quality of regenerate unfavorably. This effect is sustained during all periods of bone healing. However, this finding should be supported by experimental and human studies.

Animals↗
PubMed1980

Reliability of scaling error detection.

Reliability of scaling error detection among dental hygiene instructors is a basis for grade equity. This study tested statistically (ANOVA) grading reliability and variance factors using ten students' scaling performance scores while treating 34 patients. Nine instructors were grouped according to experience, and the patients were grouped according to four difficulty levels. The interinstructor differences were significant in the inexperienced group only. Variance analysis implied that 26 to 94 percent of the grade given is due to instructor differences rather than the students' performances. Experienced graduate students graded most consistently (26 percent of variance due to instructor differences) while faculty were less consistent (64 percent) and inexperienced graduate students exhibited marked inconsistency (94 percent). Error detection appeared to be more closely related to the instructors' educational background than to experience. Results of the study suggest the need for clinical rotation of instructors as well as for instructor calibration.

Dental Calculus↗
PubMed1993

[Animal experiment studies using a low-frequency, phase-delayed masker in inner ear diagnosis].

Endolymphatic hydrops is usually diagnosed on the basis of clinical symptoms although objective parameters for this disease can be difficult to differentiate from other disorders of the inner ear. Low-frequency acoustic biasing using a highly intensive phase-shifted low-frequency masker was studied according to its ability to determine disorders of cochlear micromechanics in diseases caused in animal models. Ossicular disruption, experimentally induced early endolymphatic hydrops and gentamycin-induced inner ear damage could be objectively determined histologically and electrophysiologically. Statistical analysis proved that the low-frequency acoustic biasing technique allowed electrophysiologic differentiation of the groups studied that was independent from known clinical parameters. To substantiate the group differences by variance analysis, an intensity of at least 100 dB SPL was required for the 52 Hz masker, and the difference in relation to the test-tone intensity had to be 10 or 20 dB SPL. The early stages of experimentally-induced endolymphatic hydrops could be identified by means of a low-distinct modulation span of the compound action potential amplitude (< 50 uV) and a reduced positive summating potential amplitude with a phase-shifted maximum value compared to the control groups. During the test phases the cochlear microphonic potentials showed only slight suppression of their amplitudes and no modulation effect when compared to the control groups. The modulation behavior of the responses could be correlated with the histologic and supposed micromechanic states of the basilar membrane and organ of Corti, thus allowing validation of the measuring technique.

Animals↗
PubMed1978

Manual and centrifugal analyzer determination of cholesterol and triglycerides with single-vial enzymatic reagents.

We have assessed Calbiochem single-vial enzymatic reagent systems for the analysis for cholesterol and triglycerides, using manual and centrifugal analyzer techniques. Analysis for cholesterol by both techniques had acceptable performance by the short-term criteria of the Center for Disease Control (CDC) during this study carried out under optimal conditions of variance. Analysis for triglycerides by the manual technique did not meet CDC criteria, and we do not recommend use of this method. Analysis for triglycerides by the centrifugal analyzer technique had acceptable short-term precision but had unacceptable accuracy at high concentrations of triglycerides; this method may be considered to have acceptable performance for routine laboratory use.

Centrifugation↗
PubMed1989

[Metabolic changes associated with obesity in adults].

In order to find if the metabolic disorders more frequently found in our obese population were similar to the ones reported in the literature for other countries, a study was conducted in a group of 34 obese subjects (10 men and 24 women) whose only apparent alteration was a body mass index above 30 (mean value: 36.8 +/- 4.6) to obtain the relation between anthropometric measurements (Quetelet index, skinfold measures and waist/hip ratio) and plasma levels of nine biochemical parameters (including lipids, lipoproteins and glucose and insulin levels after an oral glucose load). The results revealed a tendency to the android distribution of fat in the female population, a significantly elevated triglyceride and total lipids levels and a decreased in HDL-cholesterol in both sexes. Hypercholesterolemia was present mainly in the male population. The most frequent dyslipidemia was Type IV (23%) followed by type IIb (15%). Practically none of the subjects had abnormal glycemic values after the glucose load, however the insulin levels were highly elevated in 80% of the patients, resulting in a great insulin/glucose ratios. Correlation analysis showed no association of the BMI with any biochemical parameter; only the insulin area was positively associated with anthropometric measures (mainly waist/hip ratio) and with the most altered biochemical parameter, the triglycerides. Variance analysis showed that only low HDL-cholesterol values were significantly different in patients presenting high blood pressure and familiar history of diabetes.

Adolescent↗
PubMed1991

[Biological assay, reliability test, error analysis and pooled calculation for assessing leucomycin yield].

A biological assay for determining leucomycin yield was established by using a curillinear protocol (Sarcina lutea) and (2.2) dosage or (3.3) dosage protocol (Bacillus subtillis 63501). At the same time, according to the principles of biostatistics and the methods of variance analysis, reliability tests, error analysis and pooled calculations were carried out, so as to hold the confidence limit below the internationally accepted level of 5%.

Biological Assay↗
PubMed1995

[Periodogram analysis for signal and noise evaluation in roentgen video signals].

Movements of the heart, the large vessels and the gastrointestinal tract can be evaluated for diagnostic purposes using fluoroscopic video systems. A new means of quantitatively evaluating the signal and noise components of the video signal is described. The signal and noise power components are determined from the periodogram after prior Fourier analysis. Variance is reduced by averaging and keeping the measuring conditions constant. For measurements of signal transfer properties, a radiological phantom capable of producing sinusoidal movements of the edge of the object was developed. An analysis of the performance of the theoretically derived evaluation parameters was carried out at a fluoroscopic unit under clinical conditions. Periodogram analysis makes possible objective image quality evaluation in clinical motion studies and in the technical quality assurance of fluoroscopic video systems. The use of a compact PC-based video measuring system renders application both practical and easy.

Artifacts↗
PubMed1980

Influence of analytical quality on the diagnostic power of a single S-CK B test in patients with suspected acute myocardial infarction.

We have compared tow theoretical methods for assessing the effects of changing analytical quality of a clinical chemical test. The test considered was S-creatine kinase B subunit activity, used as the only diagnostic criterion for acute myocardial infarction. The two methods applied were based on (i) graphical analysis, and (ii) computer simulation. The results comprise the effects of changing analytical imprecision and bias on the weighted sum of misclassified cases on basis of the test results. The two methods yield comparable results at high analytical imprecision, but due to differences in assumptions about the error distribution of test results the difference increases with increased analytical imprecision. The graphical analysis is easily performed but is restricted in possible applications. The computer simulation is not a generally available methodology, but allows for mixing of different types of statistical distributions, which is not the case in conventional variance analysis.

Chemistry Techniques, Analytical↗