60 resultados para Anova
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BACKGROUND: Greenstick fractures suffered during growth have a high risk for refracture and posttraumatic deformity, particularly at the forearm diaphysis. The use of a preemptive completion of the fracture by manipulation of the concave cortex is controversial and data supporting this approach are few. AIM: Aim of this study was to determine the factors which predispose to refracture and deformities, and to define therapeutic strategies. METHODS: We prospectively gathered clinical and radiographic data over a period of one year on greenstick fractures of the middle third of the forearm in children as part of a multi-centre study. Endpoint was a follow-up visit at one year. Radiographic deformity, state of consolidation at resumption of physical activities and refracture rate were analysed statistically (ANOVA, Student's t-test and Pearson's chi-square test) with regard to patient age, gender, fracture type, therapy and time in plaster. RESULTS: We collected the data of 103 patients (63 boys, 40 girls), average age 6.6 years (1.3-14.5 years), the vast majority of whom had a combined greenstick fracture of the radius and ulna. 6.7% of the patients sustained a refracture within 49 days (29-76) after plaster removal. They were significantly older (p=0.017) with a significantly higher incidence of manual completion of the fracture with radiographic signs of partial consolidation (p=0.025). Residual deformities were significantly smaller after completion of the fracture compared to reduction without completion (p=0.019) or plaster fixation alone (p<0.005). CONCLUSIONS: Completion of a greenstick fracture does not prevent refracture. Nevertheless, it diminishes the extent of secondary deformities in cases where the primary angulation exceeds the remodelling capacity. Prevention of refracture should include a routine radiographic follow-up 4-6 weeks after injury with continuation of plaster fixation in cases of partial consolidation.
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OBJECTIVES: (1) To evaluate the changes in surface roughness and gloss after simulated toothbrushing of 9 composite materials and 2 ceramic materials in relation to brushing time and load in vitro; (2) to assess the relationship between surface gloss and surface roughness. METHODS: Eight flat specimens of composite materials (microfilled: Adoro, Filtek Supreme, Heliomolar; microhybrid: Four Seasons, Tetric EvoCeram; hybrid: Compoglass F, Targis, Tetric Ceram; macrohybrid: Grandio), two ceramic materials (IPS d.SIGN and IPS Empress polished) were fabricated according to the manufacturer's instructions and optimally polished with up to 4000 grit SiC. The specimens were subjected to a toothbrushing (TB) simulation device (Willytec) with rotating movements, toothpaste slurry and at three different loads (100g/250g/350g). At hourly intervals from 1h to 10h TB, mean surface roughness Ra was measured with an optical sensor and the surface gloss (Gl) with a glossmeter. Statistical analysis was performed for log-transformed Ra data applying two-way ANOVA to evaluate the interaction between load and material and load and brushing time. RESULTS: There was a significant interaction between material and load as well as between load and brushing time (p<0.0001). The microhybrid and hybrid materials demonstrated more surface deterioration with higher loads, whereas with the microfilled resins Heliomolar and Adoro it was vice versa. For ceramic materials, no or little deterioration was observed over time and independent of the load. The ceramic materials and 3 of the composite materials (roughness) showed no further deterioration after 5h of toothbrushing. Mean surface gloss was the parameter which discriminated best between the materials, followed by mean surface roughness Ra. There was a strong correlation between surface gloss and surface roughness for all the materials except the ceramics. The evaluation of the deterioration curves of individual specimens revealed a more or less synchronous course suspecting hinting specific external conditions and not showing the true variability in relation to the tested material. SIGNIFICANCE: The surface roughness and gloss of dental materials changes with brushing time and load and thus results in different material rankings. Apart from Grandio, the hybrid composite resins were more prone to surface changes than microfilled composites. The deterioration potential of a composite material can be quickly assessed by measuring surface gloss. For this purpose, a brushing time of 10h (=72,000 strokes) is needed. In further comparative studies, specimens of different materials should be tested in one series to estimate the true variability.
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ABSTRACT: BACKGROUND: Neuroprotective and neurotrophic properties of leukemia inhibitory factor (LIF) have been widely reported. In the central nervous system (CNS), astrocytes are the major source for LIF, expression of which is enhanced following disturbances leading to neuronal damage. How astrocytic LIF expression is regulated, however, has remained an unanswered question. Since neuronal stress is associated with production of extracellular adenosine, we investigated whether LIF expression in astrocytes was mediated through adenosine receptor signaling. METHODS: Mouse cortical neuronal and astrocyte cultures from wild-type and adenosine A2B receptor knock-out animals, as well as adenosine receptor agonists/antagonists and various enzymatic inhibitors, were used to study LIF expression and release in astrocytes. When needed, a one-way analysis of variance (ANOVA) followed by Bonferroni post-hoc test was used for statistical analysis. RESULTS: We show here that glutamate-stressed cortical neurons induce LIF expression through activation of adenosine A2B receptor subtype in cultured astrocytes and require signaling of protein kinase C (PKC), mitogen-activated protein kinases (MAPKs: p38 and ERK1/2), and the nuclear transcription factor (NF)-κB. Moreover, LIF concentration in the supernatant in response to 5'-N-ethylcarboxamide (NECA) stimulation was directly correlated to de novo protein synthesis, suggesting that LIF release did not occur through a regulated release pathway. Immunocytochemistry experiments show that LIF-containing vesicles co-localize with clathrin and Rab11, but not with pHogrin, Chromogranin (Cg)A and CgB, suggesting that LIF might be secreted through recycling endosomes. We further show that pre-treatment with supernatants from NECA-treated astrocytes increased survival of cultured cortical neurons against glutamate, which was absent when the supernatants were pre-treated with an anti-LIF neutralizing antibody. CONCLUSIONS: Adenosine from glutamate-stressed neurons induces rapid LIF release in astrocytes. This rapid release of LIF promotes the survival of cortical neurons against excitotoxicity.
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BACKGROUND: Circulating 25-hydroxyvitamin D [25(OH)D] concentration is inversely associated with peripheral arterial disease and hypertension. Vascular remodeling may play a role in this association, however, data relating vitamin D level to specific remodeling biomarkers among ESRD patients is sparse. We tested whether 25(OH)D concentration is associated with markers of vascular remodeling and inflammation in African American ESRD patients.METHODS: We conducted a cross-sectional study among ESRD patients receiving maintenance hemodialysis within Emory University-affiliated outpatient hemodialysis units. Demographic, clinical and dialysis treatment data were collected via direct patient interview and review of patients records at the time of enrollment, and each patient gave blood samples. Associations between 25(OH)D and biomarker concentrations were estimated in univariate analyses using Pearson's correlation coefficients and in multivariate analyses using linear regression models. 25(OH) D concentration was entered in multivariate linear regression models as a continuous variable and binary variable (<15 ng/ml and =15 ng/ml). Adjusted estimate concentrations of biomarkers were compared between 25(OH) D groups using analysis of variance (ANOVA). Finally, results were stratified by vascular access type.RESULTS: Among 91 patients, mean (standard deviation) 25(OH)D concentration was 18.8 (9.6) ng/ml, and was low (<15 ng/ml) in 43% of patients. In univariate analyses, low 25(OH) D was associated with lower serum calcium, higher serum phosphorus, and higher LDL concentrations. 25(OH) D concentration was inversely correlated with MMP-9 concentration (r = -0.29, p = 0.004). In multivariate analyses, MMP-9 concentration remained negatively associated with 25(OH) D concentration (P = 0.03) and anti-inflammatory IL-10 concentration positively correlated with 25(OH) D concentration (P = 0.04).CONCLUSIONS: Plasma MMP-9 and circulating 25(OH) D concentrations are significantly and inversely associated among ESRD patients. This finding may suggest a potential mechanism by which low circulating 25(OH) D functions as a cardiovascular risk factor.
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The ATP-binding cassette (ABC) family of proteins comprise a group of membrane transporters involved in the transport of a wide variety of compounds, such as xenobiotics, vitamins, lipids, amino acids, and carbohydrates. Determining their regional expression patterns along the intestinal tract will further characterize their transport functions in the gut. The mRNA expression levels of murine ABC transporters in the duodenum, jejunum, ileum, and colon were examined using the Affymetrix MuU74v2 GeneChip set. Eight ABC transporters (Abcb2, Abcb3, Abcb9, Abcc3, Abcc6, Abcd1, Abcg5, and Abcg8) displayed significant differential gene expression along the intestinal tract, as determined by two statistical models (a global error assessment model and a classic ANOVA, both with a P < 0.01). Concordance with semiquantitative real-time PCR was high. Analyzing the promoters of the differentially expressed ABC transporters did not identify common transcriptional motifs between family members or with other genes; however, the expression profile for Abcb9 was highly correlated with fibulin-1, and both genes share a common complex promoter model involving the NFkappaB, zinc binding protein factor (ZBPF), GC-box factors SP1/GC (SP1F), and early growth response factor (EGRF) transcription binding motifs. The cellular location of another of the differentially expressed ABC transporters, Abcc3, was examined by immunohistochemistry. Staining revealed that the protein is consistently expressed in the basolateral compartment of enterocytes along the anterior-posterior axis of the intestine. Furthermore, the intensity of the staining pattern is concordant with the expression profile. This agrees with previous findings in which the mRNA, protein, and transport function of Abcc3 were increased in the rat distal intestine. These data reveal regional differences in gene expression profiles along the intestinal tract and demonstrate that a complete understanding of intestinal ABC transporter function can only be achieved by examining the physiologically distinct regions of the gut.
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Introduction: L'évaluation de la fonction de l'épaule à l'aide de capteurscinématiques embarqués produit des mesures discriminatives etsensibles au changement. Cependant, la réalisation pratique reste tropcomplexe pour l'utilisation courante. L'objectif de cette étude était dedévelopper une méthode d'évaluation cinématique simplifié et efficace.Méthode : Une analyse secondaire a été effectuée sur les donnéesd'un score de référence, basé sur la réalisation de 7 mouvements.Trente-cinq patients ont été mesurés à l'aide d'accéléromètreset de gyroscopes en préopératoire, ainsi qu'à 3, 6 et 12mois après chirurgie de l'épaule. Les mouvements essentiels ontété identifiés à l'aide une analyse en composantes principales(ACP). Une méthode d'évaluation simplifiée a ensuite été élaboréeen effectuant des régressions multiples des mouvementssélectionnées versus le score de référence à 3 mois. Les résultatsdu score simplifié ont été comparés au score de référence paranalyse statistique (ANOVA à mesure double répétées, régressionlinéaire, taille de l'effet, limite de l'agrément et corrélationaux échelles cliniques).Resultats : Une composante d'élévation et une composante de rotationreprésentant plus de 62 % de la variance ont été identifiées.Des modèles simplifiés d'évaluation ont donc été calculés avec desrégressions multiples incluant des combinaisons de mouvementsde rotation et d'élévation : dos-tête, dos-abduction, dos-épaule, dosplafond.La comparaison du score de référence et des scores simplifiésmontrait à tous les stades : une relation fortement linéaire (R2> 0,96), une taille de l'effet comparable (d de Cohen 1,33 à 1,51 versus1,33 pour le score de référence) et une corrélation comparable avecles scores cliniques (r = 0,22 à 0,8). La différence entre les scoresse situait entre - 6,28 et + 2,78. La limite de l'agrément variait de 13à 24 %. Parmi les scores simplifiés, seul le score « dos-plafond » nemontrait pas de différence avec le score de référence pour l'interactiontemps*score (p > 0,5).Discussion-Conclusion : Un score cinématique de l'épaule comprenantuniquement deux mouvements a été développé. Plusieursmodèles de score simplifiés produisent des résultats comparablesau score de référence pour l'évaluation de groupes de patients. Lescore moyen « dos-plafond » présente un profil d'évolution dans letemps en relation étroite avec le score de référence. Par contre, ladiscordance des résultats entre le score de référence et les scoressimplifiés lors de mesures individuelles doit être prise en considérationavant une éventuelle application à des études de cas clinique.Implications : Cette nouvelle méthode d'évaluation présente desavantages pratiques pour l'évaluation objective de l'épaule. Cecipourrait favoriser l'utilisation de méthodes d'analyse informatiséedu mouvement en clinique et pour la recherche. Les résultats confirmentégalement que l'on peut obtenir une bonne appréciation de lafonction de l'épaule en demandant au patient de mettre la main dansle dos, puis de lever le bras.
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Background: Bacteria form biofilms on the surface of orthopaedic devices, causing persistent infections. Monitoring biofilm formation on bone grafts and bone substitutes is challenging due to heterogeneous surface characteristics. We analyzed various bone grafts and bone substitutes regarding their propensity for in-vitro biofilm formation caused by S. aureus and S. epidermidis. Methods: Beta-tricalciumphosphate (b-TCP, ChronOsTM), processed human spongiosa (TutoplastTM) and PMMA (PalacosTM) were investigated. PE was added as a growth control. As test strains S. aureus (ATCC 29213) and S. epidermidis RP62A (ATCC 35984) were used. Test materials were incubated with 105 cfu/ml. After 24 h, test materials were removed and washed, followed by a standardised sonication protocol. The resulting sonication fluid was plated and bacterial counts were enumerated and expressed as cfu/sample. Sonicated samples were transferred to a microcalorimeter (TA Instrument) and heat flow monitored over a 24 h period with a precision of 0.0001°C and a sensitiviy of 200 μW. Experiments were performed in triplicates to calculate the mean ± SD. One-way ANOVA analysis was used for statistical analysis. Results: Bacterial counts (log10 cfu/sample) were highest on b-TCP (S. aureus 7.67 ± 0.17; S. epidermidis 8.14 ± 0.05) while bacterial density (log10 cfu/surface) was highest on PMMA (S. aureus 6.12 ± 0.2, S. epidermidis 7.65 ± 0.13). Detection time for S. aureus biofilms was shorter for the porous materials (b-TCP and Tutoplast, p <0.001) compared to the smooth materials (PMMA and PE) with no differences between b-TCP and TutoplastTM (p >0.05) or PMMA and PE (p >0.05). In contrast, for S. epidermidis biofilms the detection time was different (p <0.001) between all materials except between Tutoplast and PE (p >0.05). Conclusion: Our results demonstrate biofilm formation with both strains on all tested materials. Microcalorimetry was able to detect quantitatively the amount of biofilm. Further studies are needed to see whether calorimetry is a suitable tool also to monitor approaches to prevent and treat infections associated with bone grafts and bone substitutes.
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Schizophrenia patients exhibit deficits in low-level processing, including pitch discrimination. This deficiency manifests in auditory evoked potentials (AEPs) as an impaired mismatch negativity (MMN), an electrophysiological response to infrequent target stimuli interspersed among frequent standard stimuli that typically peaks ~100ms post-stimulus onset. NMDA receptor antagonists have been shown to block MMN generation in both animals and humans, and NMDA dysfunction has been linked to the underlying pathophysiology of schizophrenia. A parallel line of evidence indicates that glutathione (GSH) regulation is perturbed in schizophrenia patients at the gene, protein and functional levels (Tosic et al., 2006). This GSH dysregulation leads to NMDA receptors' hypofunction through interaction with their redox site (Steullet et al., 2006). The present study aimed to modulate GSH levels in schizophrenia patients and assessed the effects of such a modulation on MMN generation mechanisms. N-acetyl-cysteine (NAC), a GSH precursor, was administered to schizophrenia patients, using a double-blind cross-over protocol. One group received NAC (2g/day) for 60 days and then placebo for another 60 days, and vice-versa for the second group. AEPs from patients were recorded at the onset of the protocol, at the point of cross-over, and at the end of the study. Participants were instructed to manually respond to target stimuli (2kHz pure tones occurring 20% of the time among 1kHz pure tones). Analyses of AEPs recorded at protocol onset indicated that patients (n=11) were significantly impaired in generating the MMN relative to age-matched controls (n=11). Specifically, the global field power (GFP), an index of AEP magnitude, was measured over the 70- 155ms post-stimulus interval and submitted to an analysis of variance (ANOVA). There was a significant interaction between population and stimulus frequency, indicating impaired MMN generation in patients at protocol onset. Analyses of AEPs recorded during administration of NAC (n=7) versus placebo (n=7) revealed the efficacy of this GSH precursor in modulating MMN generation mechanisms. ANOVA of GFP over the 70- 155ms post-stimulus interval, using stimulus frequency and treatment as within-participants variables, revealed a significant interaction and indicated that NAC can ameliorate MMN generation. We discuss these results in terms of potential therapeutic strategies for schizophrenia.
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The purpose of this study was to evaluate a new method of measuring rolling resistance in treadmill cycling and to establish its sensitivity and reproducibility. One participant was asked to keep a bicycle in equilibrium on a treadmill without pedalling at a constant speed of 5.56 m x s(-1), which was held in place in the front by a dynamometer. For each condition, the method consisted of 11 measurements of the force required to hold the cycle at different treadmill slopes (0-10%, increment 1%). The coefficient of rolling resistance was calculated based on the forces applied to the bicycle in equilibrium. To test the sensitivity of the method, the bicycle was successively equipped with three tyre types (700 x 28, 700 x 23, 700 x 22) and inflation pressure was set at 150, 300, 600, 900, and 1100 kPa. To test the reproducibility of the method, a second experimenter repeated all measurements done with the 700 x 23 tyres. The method was sensitive enough to detect an effect of both tyre type and inflation pressure (P < 0.001: two-way ANOVA). The measurement of the coefficient of rolling resistance by two separate experimenters resulted in a small bias of 0.00029 (95% CI, -0.00011 to 0.00068). In conclusion, the new method is sensitive and reliable, as well as being simple and affordable.
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Many interventions promoting physical activity (PA) are effective in preventing disease onset, and although studies have found a positive relationship between health-related quality of life (HRQL) and PA, most of these studies have focused on older adults and those with chronic conditions. Less is known regarding the association between PA level and HRQL among healthy adults. Our objective was to analyse the relationship between PA level and HRQL among a sample of 573 employees aged 20-68 taking part in a workplace intervention to promote PA. Measures included HRQL (using a single item) and PA (i.e. Godin Leisure-Time Questionnaire). The Modified Canadian Aerobic Fitness Test (MCAFT) was also completed by 10% of the employees. MET-minute scores (assessing energy expenditure over one week) were compared across HRQL categories using ANOVA. A multiple linear regression analysis was conducted to further examine the relationship between HRQL and PA, controlling for potential covariates. Participants in the higher health status categories were found to report higher levels of energy expenditure (one-way ANOVA, p < 0.001). In the multiple linear regression model, each unit increase in health status level translated in a mean increase of 356 MET-minutes in energy expenditure (p < 0.001). This single-item assessment of health status explained six percent of the variance in energy expenditure. The study concludes that higher energy expenditure through PA among an adult workplace population is positively associated with increased health status, and it also suggests that a single-item HRQL measure is suitable for community- and population-based studies, reducing response burden and research costs.
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Hepatocellular apoptosis plays a major role in the pathogenesis of chronic hepatitis C. It can be measured noninvasively by determining the circulating levels of cytokeratin-18 fragments. We hypothesized that the effect of antiviral therapy on this parameter will be different in patients with a sustained virological response, relapse (REL) and nonresponse (NR). We quantified cytokeratin-18 fragments in plasma of patients participating in the Swiss Hepatitis C cohort, who received antiviral therapy without stopping because of sides effects. A total of 315 patients were included, 183 with a sustained response, 64 with NR and 68 who relapsed. Mean levels ±SD of circulating cytokeratin-18 fragments before therapy were 174 ± 172 U/L for responsders, 188 ± 145 for nonresponders and 269 ± 158 U/L for patients who relapsed. The values were significantly higher in the REL group (ANOVA P < 0.006). A sustained response was associated with a significant improvement of the plasma levels (94 ± 92 U/L, paired test P < 0.000001), whereas there was no improvement in the nonresponder group (183 ± 158 U/L) and in the relapser group (158 ± 148 U/L). There was a weak correlation between alanine aminotransferase (ALT) and cytokeratin-18 fragment levels (r² = 0.35, P < 0.000001) before therapy but not after therapy and none with hepatitis C virus (HCV) viremia. Successful antiviral therapy results in a significant decrease in circulating levels of cytokeratin-18 fragments arguing for a reduction in hepatocellular apoptosis after clearance of the HCV. Baseline cytokeratin-18 fragment levels are higher in relapsers. Correlations with ALT are weak, suggesting that these two tests measure different but related processes.
Effects of long-term estrogen replacement therapy in postmenopausal women with coronary risk factors
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Objective: Hormone replacement therapy (HRT) with estrogen alone or in concert with progesterone may exert beneficial effects on coronary endothelium-dependent vasomotion in postmenopausal women without traditional coronary risk factors. We aimed to evaluate the effect of HRT on coronary vasomotor function in postmenopausal women with traditional coronary risk factors such as hypertension, hypercholesterolemia and smoking as compared to those without HRT. Methods: Combining N-13 ammonia with PET, myocardial blood flow (MBF) was measured in ml/g/min at rest, during cold pressor test (CPT, reflecting predominantly endothelium-dependent vasomotion)and during pharmacologic vasodilation (representing predominantly endothelium-independent vasomotion) in 48 postmenopausal women with various coronary risk factors during a mean follow up (FU) of 20_9 months. postmenopausal women wer grouped according to HRT: group 1 with HRT (n_18), group 2 without HRT (n_18) and group 3 with HRT at baseline but not at FU (n_12). Results: during FU, HRT did not significantly affect lipid profile and plasma glucose levels. At baseline resting MBF was similar between groups (Table).After the FU, in group 2 and 3 the endothelium-related increase in MBF from rest to CPT (_ MBF) was significantly less than at baseline (*p_0.05) (Table). Conversely, in group 1 _MBF to CPT at FU was not significantly different from the baseline study. The group comparison of CPT-induced _MBF in group 2 and group 3 after the FU period was significantly different from group 1 (p_0.006 by ANOVA). Finally, in all three groups, hyperemic MBFs during pharmacologic vasodilation did not differ significantly between baseline and FU (Table). Conclusion: In postmenopausal women with coronary risk factors, HRT may counterbalance the adverse effects of traditional coronary risk factors on endothelium-dependent coronary vasomotion. Consequently, in addition to standard management of coronary risk factors, HRT may exert beneficial effects on the coronary endothelium that may delay the progression of coronary artery disease in postmenopausal women.
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Background: TIDratio indirectly reflects myocardial ischemia and is correlated with cardiacprognosis. We aimed at comparing the influence of three different softwarepackages for the assessment of TID using Rb-82 cardiac PET/CT. Methods: Intotal, data of 30 patients were used based on normal myocardial perfusion(SSS<3 and SRS<3) and stress myocardial blood flow 2mL/min/g)assessed by Rb-82 cardiac PET/CT. After reconstruction using 2D OSEM (2Iterations, 28 subsets), 3-D filtering (Butterworth, order=10, ωc=0.5), data were automatically processed, and then manually processed fordefining identical basal and apical limits on both stress and rest images.TIDratio were determined with Myometrix®, ECToolbox® and QGS®software packages. Comparisons used ANOVA, Student t-tests and Lin concordancetest (ρc). Results: All of the 90 processings were successfullyperformed. TID ratio were not statistically different between software packageswhen data were processed automatically (P=0.2) or manually (P=0.17). There was a slight, butsignificant relative overestimation of TID with automatic processing incomparison to manual processing using ECToolbox® (1.07 ± 0.13 vs 1.0± 0.13, P=0.001)and Myometrix® (1.07 ± 0.15 vs 1.01 ± 0.11, P=0.003) but not using QGS®(1.02 ±0.12 vs 1.05 ± 0.11, P=0.16). The best concordance was achieved between ECToolbox®and Myometrix® manual (ρc=0.67) processing.Conclusion: Using automatic or manual mode TID estimation was not significantlyinfluenced by software type. Using Myometrix® or ECToolbox®TID was significantly different between automatic and manual processing, butnot using QGS®. Software package should be account for when definingTID normal reference limits, as well as when used in multicenter studies. QGS®software seemed to be the most operator-independent software package, whileECToolbox® and Myometrix® produced the closest results.
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Background: The anti-angiogenic drug, bevacizumab (Bv), is currently used in the treatment of different malignancies including breast cancer. Many angiogenesis-associated molecules are found in the circulation of cancer patients. Until now, there are no prognostic or predictive factors identified in breast cancer patients treated with Bv. We present here the first results of the prospective monitoring of 6 angiogenesis-related molecules in the peripheral blood of breast cancer patients treated with a combination of Bv and PLD in the phase II trial, SAKK 24/06. Methods: Patients were treated with PLD (20 mg/m2) and Bv (10 mg/kg) on days 1 and 15 of each 4-week cycle for a maximum of 6 cycles, followed by Bv monotherapy maintenance (10 mg/m2 q2 weeks) until progression or severe toxicity. Plasma and serum samples were collected at baseline, after 2 months of therapy, then every 3 months and at treatment discontinuation. Enzyme-linked immunosorbent assays (Quantikine, R&D Systems and Reliatech) were used to measure the expression levels of human vascular endothelial growth factor (hVEGF), placental growth factor (hPlGF), matrix metalloproteinase 9 (hMMP9) and soluble VEGF receptors hsVEGFR-1, hsVEGFR-2 and hsVEGFR-3. The log-transformed data (to reduce the skewness) for each marker was analyzed using an analysis of variance (ANOVA) model to determine if there was a difference between the mean of the subgroups of interest (where α = 0.05). The untransformed data was also analyzed in the same manner as a "sensitivity" check. Results: 132 blood samples were collected in 41 out of 43 enrolled patients. Baseline levels of the molecules were compared to disease status according to RECIST. There was a statistically significant difference in the mean of the log-transformed levels of hMMP9 between responders [CR+PR] versus the mean in patients with PD (p-value=0.0004, log fold change=0.7536), and between patients with disease control [CR+PR+SD] and those with PD (p-value=<0.0001, log fold change=0.81559), with the log-transformed level of hMMP9 being higher for the responder group. The mean of the log-transformed levels of hsVEGFR-1 was statistically significantly different between patients with disease control [CR+PR+SD] and those with PD (p-value=0.0068, log fold change=-0.6089), where the log-transformed level of hsVEGFR-1 was lower for the responder group. The log-transformed level of hMMP9 at baseline was identified as a significant prognostic factor in terms of progression free survival (PFS): p-value=0.0417, hazard ratio (HR)=0.574 with a corresponding 95% confidence interval (0.336 - 0.979)). No strong correlation was shown either between the log-transformed levels of hsVEGF, hPlGF, hsVEGFR-2 or hsVEGFR-3 and clinical response or the occurrence of severe toxicity, or between the levels of the different molecules. Conclusions: Our results suggest that baseline plasma level of the matrix metalloproteinase, hMMP9, could predict tumor response and PFS in patients treated with a combination of Bv and PLD. These data justify further investigation in breast cancer patients treated with anti-angiogenic therapy.
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Purpose: To determine dose thresholds, in term of CTDIvol, where subtle anatomical structures of pediatric CT images becomes no more detectable and compare them to the most recent Reference Dose Levels (DRL) proposed in the UK, Germany and Switzerland. Materials and methods: A GE LightSpeed-Ultra scanner (MSCT 8 slices) was used to perform chest and abdomen acquisitions on 8 patients (age range 2 to 16 years old) to provide a set of gold standard images. Dose reductions were then simulated by introducing image noise on raw data to provide simulated CT images with CTDIvol ranging from 2 to 22 mGy. All images were reviewed and scored independently by four experienced radiologists using the VGA methodology (Visual Grading Analysis) to determine the dose threshold where a significant loss of normal anatomy conspicuity appeared. Data were analyzed with ANOVA and Tukey HSD tests, a p >0.05 was considered to be significant. Results: No significant difference in VGA scoring appeared for CTDIvol leading to image noise levels lower than 10 and 25 HU for respectively abdominal and chest acquisitions. These data can thus be used to set the AEC (automatic exposure control) system of units having similar noise properties than the GE LightSpeed-Ultra used in this study. The present DRLs proposed for pediatric CT acquisitions are compatible with an excellent image quality level. Conclusion: The differences of DRL values proposed in Europe for pediatric acquisitions are marginal and assure a very good image quality level. The results of this study allow to further optimize the acquisition protocol by giving Noise Index value to set the AEC device.