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PubMed2003

The comparison of wear characteristics of prosthodontic restorative materials.

AIM: To assess the mutual wear characteristics of various prosthodontic restorative materials. MATERIALS AND METHODS: Samples were prepared using base metal alloy, ceramics and aesthetic methyl metacrylate resin materials in cylinders with a diameter of 30 mm, height 4 mm, and a spherical shape with a diameter of 5 mm and length of 6 mm. The mutual wearing process of samples on each other in groups was tested using a pin-on disc wear tester machine. RESULTS: The data obtained were evaluated by means of variance analysis and T-test. It was determined that the percentages of the mutual wearing of the restorative materials were statistically significant (p<0.001), but whether the samples were in the upper or lower position had no statistical significance. CONCLUSION: Various prosthodontic restorative materials had wear characteristics affecting each other.

Analysis of Variance↗
PubMed2005

Systematic review and meta-analysis of randomised controlled trials of gastro-oesophageal reflux interventions for chronic cough associated with gastro-oesophageal reflux.

OBJECTIVE: To evaluate the efficacy of treatment for gastro-oesophageal reflux disease (GORD) on chronic cough in children and adults without an underlying respiratory disease. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Cochrane, Medline, and Embase databases, references from review articles. INCLUDED STUDIES: Randomised controlled trials on GORD treatment for cough in children and adults without primary lung disease. Two reviewers independently selected studies and extracted paediatric and adult data on primary (clinical failure) and secondary outcomes. RESULTS: 11 studies were included. Meta-analysis was limited to five studies in adults that compared proton pump inhibitors with placebo. All outcomes favoured proton pump inhibitors: the odds ratio for clinical failure (primary outcome) was 0.24 (95% confidence interval 0.04 to 1.27); number needed to treat (NNT) was 5 (harm 50 to infinity to benefit 2.5). For secondary outcomes, the standardised mean difference between proton pump inhibitors and placebo was -0.51 (-1.02 to 0.01) for mean cough score at the end of the trial and -0.29 (-0.62 to 0.04) for change in cough score at the end of the trial. Subgroup analysis with generic inverse variance analysis showed a significant mean change in cough (-0.41 SD units, -0.75 to -0.07). CONCLUSION: Use of a proton pump inhibitor to treat cough associated with GORD has some effect in some adults. The effect, however, is less universal than suggested in consensus guidelines on chronic cough and its magnitude of effect is uncertain.

Adult↗
PubMed1997

Genistein potentiates wild-type and delta F508-CFTR channel activity.

Effects of genistein on wild-type (wt) and delta F508-cystic fibrosis transmembrane conductance regulator (CFTR) were studied in NIH/3T3 cells stably transfected with wt or mutant CFTR cDNA. As measured by I- efflux, half-maximal concentration of agonist (K1/2) for forskolin-dependent activation was greater for delta F508-CFTR than wt-CFTR. Genistein decreased the K1/2 for both forms of the channel and increased the maximal activity of delta F508-CFTR by 3.7-fold. In cell-attached patches, 10 microM forskolin induced minimal delta F508-CFTR activity with characteristic prolonged closed times (estimated time constant, > 30 s). Genistein increased the forskolin-induced macroscopic currents of wt-CFTR and delta F508-CFTR by 3- and 19-fold, respectively. Variance analysis suggested that in the presence of forskolin and genistein the open probabilities (Po) of wt- and delta F508-CFTR were identical. In single-channel studies, at maximal adenosine 3',5'-cyclic monophosphate (cAMP) stimulation, genistein increased the Po of wt-CFTR by prolonging the open time, but, at submaximal cAMP stimulation, the Po was increased by prolonging the open time and shortening the closed time. In excised patches with CFTR channels preactivated in the cell-attached mode, genistein increased ATP-dependent wt- and delta F508-CFTR current about twofold by prolonging the open time. Our results thus suggest that phosphorylation-dependent activation of delta F508-CFTR is defective and that genistein corrects this defect at least in part by binding to the CFTR protein.

3T3 Cells↗
PubMedDate not supplied

Efficacy of occlusal plaque removal in erupting molars: a comparison of an electric toothbrush and the cross-toothbrushing technique.

The aim of this prospective crossover study was to compare the efficacy of two methods of plaque removal on partially erupted occlusal surfaces, which comprise about 80% of the sites affected by caries in schoolchildren. After a baseline examination, 16 children (aged 5-7 years) and their parents were instructed in cleaning the occlusal surface of an erupting molar either with an electric toothbrush or with a manual toothbrush in the cross-brushing technique. After 2 weeks, the proportion of the occlusal surface covered by plaque was measured again using the occlusal plaque index, a new, highly reproducible method (intraclass correlation coefficient > 0.90). For the next 2 weeks, they used the other technique. In the multifactorial variance analysis, the individual child and parents were the most important factor for the amount of plaque present. Secondly, both methods resulted in about 50% less plaque on occlusal surfaces compared to baseline (29.2%) with a slightly but significantly smaller mean value for the electric toothbrush (14.7%, manual cross-brushing technique 16.7%; p = 0.025).

Analysis of Variance↗
PubMedDate not supplied

Heart size in inbred strains of rats. Part 1. Genetic determination of the development of cardiovascular enlargement in rats.

The heart and aorta weights in 23 strains of rats and the four-way cross generation among the M520/N, SHRSP/N, SHR/N, and WKY/N strains were investigated in relation to their blood pressure in an attempt to characterize cardiovascular enlargement (increased weight of heart and aorta) from a genetic aspect. The distribution of blood pressure in these strains at 10 weeks of age was clearly divided into hypertensive and normotensive groups. In the hypertensive group, heart weight increased in proportion to blood pressure. In contrast, there was no relationship between blood pressure and heart weight in the normotensive group in spite of large strain differences in heart weights. The result of variance analysis exhibited a significant strain difference in heart weight, and the degree of genetic determination was estimated to be 65%-75%. A similar genetic influence was apparent for normotensive strains excluding hypertensive strains. The distribution of blood pressures in the four-way cross generation showed the segregation of three phenotypes consisting of normotensive, intermediate and hypertensive groups. A large variability was seen in heart weight of each group. However, the increase in average heart weight of these three groups was very small. The degree of genetic determination from the cross analysis was estimated to be 45%-65%. These results indicate that heart weight is a highly heritable trait, and that the effect of genetic factors on cardiac enlargement is larger than that of blood pressure. A similar result was obtained for the aorta weight. However, the effect of genetic factors was less important for aorta weight than for heart weight since the degree of genetic determination was estimated to be 45%-65% from the strain comparison and 35%-60% from the cross analysis.

Age Factors↗
PubMed1980

Programming and running radioimmunoassay in the h-TSH screening procedure using dried blood spots and the NE1600 gamma counter on line to the HP9815S calculator.

Screening for hypothyroidism has been achieved by seeking raised concentrations of thyroid stimulating hormone (h-TSH) in dried blood samples collected on absorbent paper from some 1700 newborn babies each week using double antibody radioimmunoassay and 125I-label counting on a NE1600 gamma counter linked to a HP9815S desk top calculator. Specificity, accuracy, and quality control of the assay have been investigated. The calculator programme stores all count, time, and calculated data and uses log-log function formation and third-power homoscedastic polynomial fit to the calibration data followed, if necessary, by elimination of outliers set at P = 0.5%. Branching in the calculation procedure provides the ability to process sample data in subgroups, completely to reprocess data (including presentation in a form suitable for making a histogram plot), and to reset without loss of data in case of instrument or main power failure. Variance analysis was used to select the minimum duration of count (50 s), and it was demonstrated that homoscedasticity pertains in the regression calculation.

Analysis of Variance↗
PubMed2005

Brain-derived neurotrophic factor enhances GABA release probability and nonuniform distribution of N- and P/Q-type channels on release sites of hippocampal inhibitory synapses.

Long-lasting exposures to brain-derived neurotrophic factor (BDNF) accelerate the functional maturation of GABAergic transmission in embryonic hippocampal neurons, but the molecular bases of this phenomenon are still debated. Evidence in favor of a postsynaptic site of action has been accumulated, but most of the data support a presynaptic site effect. A crucial issue is whether the enhancement of evoked IPSCs (eIPSCs) induced by BDNF is attributable to an increase in any of the elementary parameters controlling neurosecretion, namely the probability of release, the number of release sites, the readily releasable pool (RRP), and the quantal size. Here, using peak-scaled variance analysis of miniature IPSCs, multiple probability fluctuation analysis, and cumulative amplitude analysis of action potential-evoked postsynaptic currents, we show that BDNF increases release probability and vesicle replenishment with little or no effect on the quantal size, the number of release sites, the RRP, and the Ca2+ dependence of eIPSCs. BDNF treatment changes markedly the distribution of Ca2+ channels controlling neurotransmitter release. It enhances markedly the contribution of N- and P/Q-type channels, which summed to >100% ("supra-additivity"), and deletes the contribution of R-type channels. BDNF accelerates the switch of presynaptic Ca2+ channel distribution from "segregated" to "nonuniform" distribution. This maturation effect was accompanied by an uncovered increased control of N-type channels on paired-pulse depression, otherwise dominated by P/Q-type channels in untreated neurons. Nevertheless, BDNF preserved the fast recovery from depression associated with N-type channels. These novel presynaptic BDNF actions derive mostly from an enhanced overlapping and better colocalization of N- and P/Q-type channels to vesicle release sites.

Analysis of Variance↗
PubMed2001

Application of deterministic model of isothermals for population dynamics of Synthesiomyia nudiseta (Diptera, Muscidae).

The isothermal deterministic model adherence was studied to evaluate the population dynamic of Synthesiomyia nudiseta (Diptera, Muscidae). The linear form of equation obtained for the experiments in the several phases, were for Egg: 1/D = -0.18 + 0.02. T; Larva: 1/D = -0.028 + 0.01. T; Pupa: 1/D = -0.069 + 0.01. T; and Adult: 1/D = -0.4178 + 0.02. T. In function of temperature, S. nudiseta can present from 4.18 to 8.95 and from 4.91 to 8.99 generations per year, when calculated through the equations of development and through the simulations, respectively. And the higher the temperature the larger the generation number. Through variance analysis it was verified the significance for the regression equations in relation to the annual generation number (Ng/year) of S. nudiseta in function of the isothermals, for two studied situations. It was obtained a significance of 0,1%. The regression equations obtained for these situations were: Ng/year = 5.4 + 0.5. T and Ng/year = 5.1 + 0.52. T. The number of generations of S. nudiseta varies linearly with the isothermal. Besides that, the number of annual generations for each isothermal does not differ statistically when calculated through the development equations or through the simulations. Such conditions suggest the adaptation of the deterministic model adopted.

Analysis of Variance↗
PubMed2006

[Relationship between body mass index and self-perception among university students].

OBJECTIVE: To assess the relationship between body mass index and self-perception of body image. METHODS: A study was carried out in a sample comprising 106 female and male university students aged 18 years or more in Ribeirão Preto, Southeastern Brazil, in 2003. The Contour Drawing Rating Scale and Visual Analogue Scale were used to evaluate body image perception; the former was applied using two different psychometric methods. A body image questionnaire was used to assess the subjective component of body image. Subjects were classified according to body mass index. Statistical analyses were performed through variance analysis and Newman-Keuls post-hoc test. RESULTS: Most normal weight or overweight women (87%) overestimated their body size while obese women and all men (73%), regardless of their BMI, underestimated their body size. The differences of body image perception between men and women were statistically significant as well as the overall dissatisfaction with their perceived body size, revealed by a desired lower body mass index. Overweight women were more concerned and uncomfortable with their own body. CONCLUSIONS: Both men and women had a distorted self-perception of body image, underestimating or overestimating it. The study results suggest dissatisfaction of subjects with their body image as they desire to have leaner bodies.

Adult↗
PubMedDate not supplied

Comparison of cephalometric measurements from three radiological clinics.

The orthodontic documentation carried out in radiological clinics is essential for diagnosis, planning and control of the orthodontic treatment. Amongst the diagnosis elements used are the cephalometric measurements, and errors can be incorporated as they are obtained. The objective of this work was to evaluate the values of some cephalometric measurements obtained in three radiological clinics using 30 lateral cephalometric radiographs of the head randomly chosen from the archives of the Department of Child Dentistry (Discipline of Orthodontics), School of Dentistry of Piracicaba, UNICAMP. These values were compared with the measurements obtained manually (control group) using variance analysis and Tukeys and Friedmans tests. Of the fourteen cephalometric measurements evaluated, the results demonstrated that only four of them presented statistically significant differences: IMPA, 1-NA, FMA, and H-nose. We concluded that although the majority of the mean cephalometric values did not present statistically significant differences, a great variability in the results was found when all the radiographic values were compared. This variability may influence the interpretation of the cephalometric measurements. Hence, we suggest that when the practitioner receives orthodontic documentation, he/she should redo the cephalometric analysis and compare the measurement values found with those presented to him. In addition, the practitioner should be prepared to use other elements for diagnosis, planning and control of the orthodontic treatment.

Analysis of Variance↗
PubMed1995

Lack of effect of oral hygiene training on periodontal disease progression over 3 years in adolescents.

A comprehensive new oral hygiene training program has lately been described and found effective in controlling dental plaque formation and in significantly reducing the incidence of approximal dental caries and gingivitis in adolescents. This study investigated the long-term effect of plaque control on the progression of periodontal diseases in adolescents. A group of 227 Brazilian schoolchildren were followed up over a period of 3 years. The children were divided randomly into 3 groups. The first group was given a needs-related intensive program which combined detailed information to parents and children pertaining to the etiology and prevention of dental diseases, instructions in self-diagnosis of plaque and gingivitis, and a detailed oral hygiene training based on individual needs, together with continued feedback and motivation during the entire 3 years. The second group was given a similar program, but through shorter sessions and with no motivation and feedback and no training in self-diagnosis. A control group received no motivation sessions or oral hygiene training. The 3 groups were examined radiographically at baseline and annually at 3 subsequent occasions. The data were analyzed with a multi-level variance analysis. The frequency of subjects showing sites with alveolar bone loss increased steadily during the entire period in all groups. Neither of the training programs had a significant effect on the alveolar bone level during 3 years compared to the control group. Generally, girls demonstrated higher proportions of approximal tooth surfaces showing radiographic bone loss, though not statistically significant. In this population the supragingival plaque control lacked any significant effect on periodontal disease progression.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Avascular necrosis of bone after cardiac transplantation. Prevalence and relationship to administration and dosage of steroids.

We studied the relationship of the administration and dosage of steroids to the development of avascular necrosis of bone in 168 patients who had had a heart transplantation (156 patients) or a heart and lung transplantation (twelve patients). One hundred and forty-one of the patients were male and twenty-seven were female. The average age was forty-five years (range, seven to sixty-six years). The average duration of follow-up was forty months (range, twelve to eighty months). Avascular necrosis developed in five patients (3 per cent). The femoral head was involved in three patients (bilaterally in two and unilaterally in one), the medial femoral condyle was involved bilaterally in one, and several sites were involved in the fifth patient. The avascular necrosis was diagnosed an average of five months (range, two to eleven months) after the transplantation. In order to evaluate the influence of the dosage of the steroids on the development of avascular necrosis of bone, the doses of prednisone and Solu-Medrol (methylprednisolone) at one week, one month, six months, and one year after the transplantation were calculated for each patient. There was no association between the cumulative dose of prednisone and the development of avascular necrosis. There was, however, a strong statistical association (p = 0.005), as determined with pooled two-tailed variance analysis, between the cumulative dose of Solu-Medrol administered in the first month after the transplantation and the development of avascular necrosis.

Adolescent↗
PubMed1997

Intrapulpar temperature during continuous CO2 laser irradiation in human molars: an in vitro study.

To establish safety parameters, we in vitro studied the increase in intrapulpal temperature caused by the use of a cw CO2 laser. A thermistor was implanted in the inner part of the pulpal chamber of 25 human lower third molars to measure the intrapulpal temperature produced by laser powers between 2-10 W and exposure times of 0.5-25.0 s. The Pearson linear correlation factor applied to the measured values showed there is a direct relationship between the independent variable and the applied power. A variance analysis produced the linear regression equation: T = 1.10 + (0.127)E where T is the temperature and E the energy. The results showed that, with a power of 4 W and maximum exposure time of 2:5 s (10 J) and a power density of 12,738.85 W cm-2, there will be no damaging reactions affecting the pulpal tissues.

Analysis of Variance↗
PubMed2007

Variance component analysis of quantitative trait loci for pork carcass composition and meat quality on SSC4 and SSC11.

In a previous study, QTL for carcass composition and meat quality were identified in a commercial finisher cross. The main objective of the current study was to confirm and fine map the QTL on SSC4 and SSC11 by genotyping an increased number of individuals and markers and to analyze the data using a combined linkage and linkage disequilibrium analysis method. A modified version of the method excludes linkage disequilibrium information from the analysis, enabling the comparison of results based on linkage information only or results based on combined linkage and linkage disequilibrium information. Nine additional paternal half-sib families were genotyped for 18 markers, resulting in a total of 1,855 animals genotyped for 15 and 13 markers on SSC4 and SSC11, respectively. The QTL affecting meat color on SSC4 was confirmed, whereas the QTL affecting LM weight could not be confirmed. The combined linkage and linkage disequilibrium analysis resulted in the identification of new significant effects for 14 traits on the 2 chromosomes. Heritabilities of the QTL effects ranged from 1.8 to 13.2%. The analysis contributed to a more accurate positioning of QTL and further characterized their phenotypic effect. However, results showed that even greater marker densities are required to take full advantage of linkage disequilibrium information and to identify haplotypes associated with favorable QTL alleles.

Adipose Tissue↗
PubMed1997

C-reactive protein in uncomplicated parturients delivered by cesarean section.

BACKGROUND: The purpose of this study was to determine normal values and evaluate clinical variables associated with postoperative C-reactive protein serum concentration after uncomplicated abdominal delivery. METHODS: C-reactive protein serum concentrations were determined serially by a quantitative immunoturbidimetric assay in 479 clinically non-infected parturients undergoing uncomplicated Cesarean section, before operation and during the first week of puerperium. Associations between clinical variables and maximal postoperative C-reactive protein levels were examined by variance analysis. RESULTS: The preoperative values were significantly higher in parturients from whom samples were obtained after the onset of labor and/or rupture of the membranes (16 +/- 10 (s.d.) mg/l) compared with the preoperative values obtained from parturients operated with no labor and intact membranes (12 +/- 7 (s.d.) mg/l) (p < 0.0001). An overall significant increase was observed in C-reactive protein concentrations after delivery, peaking on the second postoperative day, compared with the preoperative values. In the parturients operated upon after the onset of labor or ruptured membranes, postoperative values were 24% higher up to the sixth postoperative day than in parturients operated upon with intact membranes and no labor. The onset of labor, duration of operation, the number of vaginal examinations and the duration of internal monitoring before operation were associated with the maximal postoperative C-reactive protein concentrations, but they explained only 9% of postoperative CRP level variation. CONCLUSIONS: The wide range of serum C-reactive protein concentrations during puerperium complicates its use as a simple marker in obstetric postoperative complications. However, after normal uncomplicated operative delivery, C-reactive protein concentrations rapidly decrease towards the baseline after the second to third postoperative day.

Adult↗
PubMed1984

Variability in isolate recovery rates from multiple and single breeds of outbred pigmented rabbits in an experimental model of Candida keratitis.

We evaluated variability of isolate recovery rates in an experimental model of Candida keratitis for both heterogeneous, pigmented, outbred rabbits and homogeneous Dutch-belted rabbits. Our purpose was to achieve more precise evaluation of topical antifungal agents in our model by substantially reducing the component of variance due to inter-rabbit differences. For the homogeneous Dutch-belted rabbits, the overall variance was reduced by a factor of 2.34 (p = 0.18) vis a vis the heterogenous outbred rabbits. The greatest reduction, a factor of 3.5, was achieved for the inter-rabbit component of variance. The upper bound for the hereditability measure was reduced from 29% to 18%. These data suggest that (1) researchers using animal models should perform a components of variance analysis to identify the factors influencing experimental precision, and (2) for our model, additional reduction in variability must come from refinement of experimental technique.

Analysis of Variance↗
PubMed2003

[Clinical investigation on characteristics of traditional Chinese medical syndrome of hepatocirrhosis].

OBJECTIVE: To explore the characteristics of traditional Chinese medical syndrome (TCM syndrome) of hepatocirrhosis. METHODS: Clinical information from the four diagnosis methods of traditional Chinese medicine (TCM) and related laboratorial indexes were systematically collected from 223 hepatocirrhosis cases, and the multi-statistical methods including systematic cluster analysis, principal component analysis, stepwise discrimination and variance analysis were made with the software SAS 6.11. RESULTS: Multi-analysis showed that there were 3 categories of syndrome characteristics. Type 1 (134 cases): damp heat, blood stasis, deficiency of liver and spleen Qi; Type 2 (62 cases): deficiency of both Qi and Yin with severe deficiency of Qi, heat with severe dampness, blood stasis; Type 3 (27 cases): deficiency of both Qi and Yin with severe deficiency of Yin, stasis and heat or dampness. Analysis of the changes of the related laboratorial indexes among the three types of syndrome showed that Type 1 mainly manifested asthenia syndrome with sthenia syndrome, and its indexes of AST, ALT, GGT levels were markedly higher than those of Type 2 and Type 3, both of which mainly showed sthenia syndrome with asthenia syndrome, and that Type 3 was in active inflammation, deficiency of both Qi and Yin (deficiency of Yin > deficiency of Qi), and its FN, Alb, FV, FVII, PLT, PCT levels were obviously reduced. CONCLUSION: The multi-statistical methods can reveal the characteristics and regularity of TCM syndrome of hepatocirrhosis, and the 3 categories of syndrome characteristics basically conform to clinical manifestations. The result of TCM syndrome distribution and laboratorial indexes infer that damp heat is the pathological basis of hepatocirrhosis, and the degree of liver function disorder and liver damage may be the pathological basis of deficiency of Yin of both liver and kidney.

Adult↗