Correction to: Relationship between tumor biomarkers and efficacy in MARIANNE, a phase III study of trastuzumab emtansine ± pertuzumab versus trastuzumab plus taxane in HER2-positive advanced breast cancer.

Following publication of the original article [1], the authors reported the following errors in the article.

Relationship between tumor biomarkers and efficacy in MARIANNE, a phase III study of trastuzumab emtansine ± pertuzumab versus trastuzumab plus taxane in HER2-positive advanced breast cancer.

BACKGROUND: The phase III EMILIA and TH3RESA trials demonstrated clinical benefits of trastuzumab emtansine (T-DM1) therapy in patients with previously treated HER2-positive metastatic breast cancer (MBC). Data from these and other trials showed that T-DM1-associated survival benefits were observed across biomarker subgroups tested in these trials. Prespecified, exploratory analyses of the phase III MARIANNE study examined the effects of HER2-related biomarkers on PFS in patients administered T-DM1 in the first-line MBC setting. METHODS: In MARIANNE, patients with previously untreated HER2-positive MBC were randomized (1:1:1) to trastuzumab plus taxane, T-DM1 plus placebo, or T-DM1 plus pertuzumab. Biomarker subgroups included HER2 and HER3 mRNA expression levels (≤median vs. >median), HER2 staining intensity (IHC 3+ vs. 2+ vs. 0/1+), PIK3CA status (mutated vs. non-mutated), PTEN H-score (≤median vs. >median), and PTEN protein expression level (0 vs. 1+ vs. 2+ vs. 3+ vs. 4+). PFS was analyzed descriptively for each subgroup using Kaplan-Meier methodology. Additional exploratory post-hoc analyses evaluated the effects of HER2 heterogeneity. Multivariate analyses were also performed. RESULTS: Median PFS was numerically longer for patients with HER2 mRNA levels >median versus ≤median across treatment arms. In general, there were no predictive biomarkers of benefit for either T-DM1 treatment arm; most hazard ratios were close to 1 with wide confidence intervals that included the value 1. Focal HER2 expression (IHC 3+ or IHC 2+) was present in 3.8% of patients and was associated with numerically shorter PFS in the T-DM1-containing treatment arms versus trastuzumab plus taxane. Compared with non-mutated PIK3CA, mutated PIK3CA was associated with numerically shorter median PFS across treatment groups. Post-hoc multivariate analysis showed HER2 mRNA expression and mutated PIK3CA were prognostic for PFS (P ≤ 0.001 for both biomarkers). CONCLUSIONS: In MARIANNE, biomarkers related to the HER2 pathway did not have predictive value for PFS when comparing T-DM1 (with or without pertuzumab) with trastuzumab plus taxane. However, HER2 mRNA level and PIK3CA mutation status showed prognostic value. Evaluation of other potential biomarkers, including immune markers, is ongoing. TRIAL REGISTRATION: Registration number: NCT01120184 . Date of registration: April 28, 2010 (registered prospectively).

Trastuzumab Emtansine With or Without Pertuzumab Versus Trastuzumab Plus Taxane for Human Epidermal Growth Factor Receptor 2-Positive, Advanced Breast Cancer: Primary Results From the Phase III MARIANNE Study.

Purpose Trastuzumab and pertuzumab are human epidermal growth factor receptor 2 (HER2) -targeted monoclonal antibodies, and trastuzumab emtansine (T-DM1) is an antibody-drug conjugate that combines the properties of trastuzumab with the cytotoxic activity of DM1. T-DM1 demonstrated encouraging efficacy and safety in a phase II study of patients with previously untreated HER2-positive metastatic breast cancer. Combination T-DM1 and pertuzumab showed synergistic activity in cell culture models and had an acceptable safety profile in a phase Ib and II study. Methods In the MARIANNE study, 1,095 patients with centrally assessed, HER2-positive, advanced breast cancer and no prior therapy for advanced disease were randomly assigned 1:1:1 to control (trastuzumab plus taxane), T-DM1 plus placebo, hereafter T-DM1, or T-DM1 plus pertuzumab at standard doses. Primary end point was progression-free survival (PFS), as assessed by independent review. Results T-DM1 and T-DM1 plus pertuzumab showed noninferior PFS compared with trastuzumab plus taxane (median PFS: 13.7 months with trastuzumab plus taxane, 14.1 months with T-DM1, and 15.2 months with T-DM1 plus pertuzumab). Neither experimental arm showed PFS superiority to trastuzumab plus taxane. Response rate was 67.9% in patients who were treated with trastuzumab plus taxane, 59.7% with T-DM1, and 64.2% with T-DM1 plus pertuzumab; median response duration was 12.5 months, 20.7 months, and 21.2 months, respectively. The incidence of grade ≥ 3 adverse events was numerically higher in the control arm (54.1%) versus the T-DM1 arm (45.4%) and T-DM1 plus pertuzumab arm (46.2%). Numerically fewer patients discontinued treatment because of adverse events in the T-DM1 arms, and health-related quality of life was maintained for longer in the T-DM1 arms. Conclusion T-DM1 showed noninferior, but not superior, efficacy and better tolerability than did taxane plus trastuzumab for first-line treatment of HER2-positive, advanced breast cancer.

Transcriptomics hit the target: Monitoring of ligand-activated and stress response pathways for chemical testing.

High content omic methods provide a deep insight into cellular events occurring upon chemical exposure of a cell population or tissue. However, this improvement in analytic precision is not yet matched by a thorough understanding of molecular mechanisms that would allow an optimal interpretation of these biological changes. For transcriptomics (TCX), one type of molecular effects that can be assessed already is the modulation of the transcriptional activity of a transcription factor (TF). As more ChIP-seq datasets reporting genes specifically bound by a TF become publicly available for mining, the generation of target gene lists of TFs of toxicological relevance becomes possible, based on actual protein-DNA interaction and modulation of gene expression. In this study, we generated target gene signatures for Nrf2, ATF4, XBP1, p53, HIF1a, AhR and PPAR gamma and tracked TF modulation in a large collection of in vitro TCX datasets from renal and hepatic cell models exposed to clinical nephro- and hepato-toxins. The result is a global monitoring of TF modulation with great promise as a mechanistically based tool for chemical hazard identification.

Application of RPTEC/TERT1 cells for investigation of repeat dose nephrotoxicity: A transcriptomic study.

The kidney is a major target organ for toxicity. Incidence of chronic kidney disease (CKD) is increasing at an alarming rate due to factors such as increasing population age and increased prevalence of heart disease and diabetes. There is a major effort ongoing to develop superior predictive models of renal injury and early renal biomarkers that can predict onset of CKD. In the EU FP7 funded project, Predict-IV, we investigated the human renal proximal tubule cells line, RPTEC/TERT1 for their applicability to long term nephrotoxic mechanistic studies. To this end, we used a tiered strategy to optimise dosing regimes for 9 nephrotoxins. Our final testing protocol utilised differentiated RPTEC/TERT1 cells cultured on filter inserts treated with compounds at both the apical and basolateral side, at concentrations not exceeding IC10, for 14 days in a 24 h repeat application. Transepithelial electrical resistance and supernatant lactate were measured over the duration of the experiments and genome wide transcriptomic profiles were assayed at day 1, 3 and 14. The effect of hypoxia was investigated for a subset of compounds. The transcriptomic data were analysed to investigate compound-specific effects, global responses and mechanistically informative signatures. In addition, several potential clinically useful renal injury biomarkers were identified.

Synergistic combination of valproic acid and oncolytic parvovirus H-1PV as a potential therapy against cervical and pancreatic carcinomas.

The rat parvovirus H-1PV has oncolytic and tumour-suppressive properties potentially exploitable in cancer therapy. This possibility is being explored and results are encouraging, but it is necessary to improve the oncotoxicity of the virus. Here we show that this can be achieved by co-treating cancer cells with H-1PV and histone deacetylase inhibitors (HDACIs) such as valproic acid (VPA). We demonstrate that these agents act synergistically to kill a range of human cervical carcinoma and pancreatic carcinoma cell lines by inducing oxidative stress, DNA damage and apoptosis. Strikingly, in rat and mouse xenograft models, H-1PV/VPA co-treatment strongly inhibits tumour growth promoting complete tumour remission in all co-treated animals. At the molecular level, we found acetylation of the parvovirus nonstructural protein NS1 at residues K85 and K257 to modulate NS1-mediated transcription and cytotoxicity, both of which are enhanced by VPA treatment. These results warrant clinical evaluation of H-1PV/VPA co-treatment against cervical and pancreatic ductal carcinomas.

Transcriptomic hepatotoxicity signature of chlorpromazine after short- and long-term exposure in primary human sandwich cultures.

Drug-induced liver injury is the most frequent reason for market withdrawal of approved drugs, and is difficult to predict in animal models. Here, we analyzed transcriptomic data derived from short- and long-term cultured primary human hepatocytes (PHH) exposed to the well known human hepatotoxin chlorpromazine (CPZ). Samples were collected from five PHH cultures after short-term (1 and 3 days) and long-term (14 days) repeat daily treatment with 0.1 or 0.2 µM CPZ, corresponding to C(max). Two PHH cultures were additionally treated with 1 µM CPZ, and the three others with 0.02 µM CPZ. Differences in the total number of gene changes were seen between donors and throughout treatment. Specific transcriptomic hepatotoxicity signatures were created for CPZ and consisted of inflammation/hepatitis, cholestasis, and liver proliferation in all five donors, as well as fibrosis and steatosis, which were observed in four of five donors. Necrosis was present in three of five donors, and an indicative signature of cirrhosis was observed after long-term 14-day repeat treatment, also in three of five donors. The inter-donor variability in the inflammatory response to CPZ treatment was associated with variability in the strength of the response of the transcriptomic hepatotoxicity signatures, suggesting that features of inflammation could be related to the idiosyncratic hepatotoxic effects of CPZ in humans.

Design of a testing strategy using non-animal based test methods: lessons learnt from the ACuteTox project.

In the framework of toxicology, a testing strategy can be viewed as a series of steps which are taken to come to a final prediction about a characteristic of a compound under study. The testing strategy is performed as a single-step procedure, usually called a test battery, using simultaneously all information collected on different endpoints, or as tiered approach in which a decision tree is followed. Design of a testing strategy involves statistical considerations, such as the development of a statistical prediction model. During the EU FP6 ACuteTox project, several prediction models were proposed on the basis of statistical classification algorithms which we illustrate here. The final choice of testing strategies was not based on statistical considerations alone. However, without thorough statistical evaluations a testing strategy cannot be identified. We present here a number of observations made from the statistical viewpoint which relate to the development of testing strategies. The points we make were derived from problems we had to deal with during the evaluation of this large research project. A central issue during the development of a prediction model is the danger of overfitting. Procedures are presented to deal with this challenge.

Evaluation of aggregating brain cell cultures for the detection of acute organ-specific toxicity.

As part of the ACuteTox project aimed at the development of non-animal testing strategies for predicting human acute oral toxicity, aggregating brain cell cultures (AGGR) were examined for their capability to detect organ-specific toxicity. Previous multicenter evaluations of in vitro cytotoxicity showed that some 20% of the tested chemicals exhibited significantly lower in vitro toxicity as expected from in vivo toxicity data. This was supposed to be due to toxicity at supracellular (organ or system) levels. To examine the capability of AGGR to alert for potential organ-specific toxicants, concentration-response studies were carried out in AGGR for 86 chemicals, taking as endpoints the mRNA expression levels of four selected genes. The lowest observed effect concentration (LOEC) determined for each chemical was compared with the IC20 reported for the 3T3/NRU cytotoxicity assay. A LOEC lower than IC20 by at least a factor of 5 was taken to alert for organ-specific toxicity. The results showed that the frequency of alerts increased with the level of toxicity observed in AGGR. Among the chemicals identified as alert were many compounds known for their organ-specific toxicity. These findings suggest that AGGR are suitable for the detection of organ-specific toxicity and that they could, in conjunction with the 3T3/NRU cytotoxicity assay, improve the predictive capacity of in vitro toxicity testing.

Data management in large-scale collaborative toxicity studies: how to file experimental data for automated statistical analysis.

High-throughput screening approaches are carried out for the toxicity assessment of a large number of chemical compounds. In such large-scale in vitro toxicity studies several hundred or thousand concentration-response experiments are conducted. The automated evaluation of concentration-response data using statistical analysis scripts saves time and yields more consistent results in comparison to data analysis performed by the use of menu-driven statistical software. Automated statistical analysis requires that concentration-response data are available in a standardised data format across all compounds. To obtain consistent data formats, a standardised data management workflow must be established, including guidelines for data storage, data handling and data extraction. In this paper two procedures for data management within large-scale toxicological projects are proposed. Both procedures are based on Microsoft Excel files as the researcher's primary data format and use a computer programme to automate the handling of data files. The first procedure assumes that data collection has not yet started whereas the second procedure can be used when data files already exist. Successful implementation of the two approaches into the European project ACuteTox is illustrated.

Evaluation of riproximin binding properties reveals a novel mechanism for cellular targeting.

Riproximin is a cytotoxic type II ribosome-inactivating protein showing high selectivity for tumor cell lines. Its binding to cell surface glycans is crucial for subsequent internalization and cytotoxicity. In this paper, we describe a unique mechanism of interaction and discuss its implications for the cellular targeting and cytotoxicity of riproximin. On a carbohydrate microarray, riproximin specifically bound to two types of asialo-glycans, namely to bi- and triantennary complex N-glycan structures (NA2/NA3) and to repetitive N-acetyl-D-galactosamine (GalNAc), the so-called clustered Tn antigen, a cancer-specific O-glycan on mucins. Two glycoproteins showing high riproximin binding, the NA3-presenting asialofetuin and the clustered Tn-rich asialo-bovine submaxillary mucin, were subsequently chosen as model glycoproteins to mimic the binding interactions of riproximin with the two types of glycans. ELISA analyses were used to relate the two binding specificities of riproximin to its two sugar binding sites. The ability of riproximin to cross-link the two model proteins revealed that binding of the two types of glycoconjugates occurs within different binding sites. The biological implications of these binding properties were analyzed in cellular assays. The cytotoxicity of riproximin was found to depend on its specific and concomitant interaction with the two glycoconjugates as well as on dynamic avidity effects typical for lectins binding to multivalent glycoproteins. The presence of definite, cancer-related structures on the cells to be targeted determines the therapeutic potency of riproximin. Due to its cross-linking ability, riproximin is expected to show a high degree of specificity for cells exposing both NA2/NA3 and clustered Tn structures.

The impact of data transformations on concentration-response modeling.

Concentration-response studies are performed to investigate the potency of the substance under investigation. Data are typically evaluated using non-linear regression. A common model is the log-logistic model which includes parameters for lower and upper boundary of mean response, EC50 and Hill slope. Often, response and/or concentration data are transformed before proceeding with the analysis of their relationship. This is motivated by practical reasons, including comparability of results across different assays. We prove mathematically that a linear transformation of data will not change the EC50 and Hill slope estimates and only results in an identical transformation of the estimated parameters for lower and upper boundary of mean response. However, fixing some of the parameters may lead to erroneous estimates. This is of practical relevance when data are corrected for background signal and normalized by background corrected solvent control and a reduced model is used in which the response range is fixed between 100% and 0%. Computer simulations and a real data example are used to illustrate the impact of data transformations on parameter estimation. We further shed light on some common problems arising in the analysis of concentration-response data. Recommendations for practical implementation in concentration-response analysis are provided.

Semiautomated versus manual evaluation of liver metastases treated by radiofrequency ablation.

PURPOSE: To determine the accuracy of semiautomated volume and density measurements of liver metastases from colorectal and breast cancer before and after radiofrequency (RF) ablation compared with manual evaluation. MATERIALS AND METHODS: Twenty-five patients (mean age, 63.2 years +/- 10.7) with 50 known liver metastases from underlying primary breast (n = 15) or colorectal cancer (n = 35) underwent triphasic contrast-enhanced multidetector computed tomography (CT) to evaluate hepatic tumor load and localization before RF ablation and for postinterventional follow-up. Each lesion was quantified in terms of volume and CT value (in HU) with a semiautomated software tool and manually by an experienced radiologist before and 4 months after RF ablation. RESULTS: Before RF ablation, all 50 liver metastases, and after ablation, 49 of 50 ablation zones (98%), were correctly evaluated by the software. Mean lesion volumes before and after the intervention were 5.5 cm(3) and 22.4 cm(3), respectively. Corresponding concordance correlation coefficients between measurement techniques were 0.98 and 0.99, respectively, for volume; and 0.90 and 0.76, respectively, for CT value. CONCLUSIONS: Compared with manual measurements, semiautomated volumetric assessment of liver metastases before and after RF ablation demonstrated a high degree of correlation. Agreement of attenuation was slightly worse, particularly when assessing the postinterventional multidetector CT examination, probably because of the different regions of interest used for manual and semiautomated assessment of CT values.

[Non-contact monitoring of heart and lung activity using magnetic induction measurement in a neonatal animal model]. / Kontaktlose Uberwachung von Atemtätigkeit und Herzaktion mittels magnetischer Bioimpedanzmessung in einem neonatalen Tiermodell.

BACKGROUND: Magnetic induction measurement (MIM) allows the identification of resistance in biologic tissues by alternating magnetic fields. These occur when well-conducting (blood) and poor-conducting matter (air) is moved through the thorax during heart and lung activity. As a result, allocation of the resistance changes and the total resistance of the thorax is shifted. By using coils, these changes can be registered in a non-contact manner and recorded. To date, this measuring principle was employed only in adult volunteers or in full-grown pigs. A neonatal animal model has not yet been described. The aim of this study was to test the hypothesis that non-contact monitoring of heart and lung activity using MIM in a porcine newborn piglet model can be applied in order to evaluate neonatal disorders of heart and lung activity in the future. MATERIALS AND METHODS: By using five coils (three measurement and two excitation coils), placed at the bottom of an experimental incubator, magnetic induction changes, depending on the heart and lung activity in 16 analgosedated piglets, were simultaneously measured and compared with pulse oximetry and airflow detection (flow resistance and pressure differential sensor) as reference signals. In addition, spontaneous breathing, including apnea, CPAP (continuous positive airway pressure to prevent end-expiratory alveolar collapse, flow 8 l/min; pressure 5 cm H(2)O), mechanical ventilation (inspiratory pressure 14 cm H(2)O; frequency 40/min) and high frequency oxygenation ventilation (HFOV, ventilation method in lung failure) (frequency 10 Hz, mean pressure 10 cm H(2)O, amplitude 1.5) were performed. Lung activity with MIM compared with the reference signal was estimated with a detection rate (%) of "correct registered lung activity". To quantify the analogy between MIM and reference signal for heart activity, the concordance correlation coefficient after Lin (95% confidence interval) and the Bland-Altman plot were calculated. RESULTS AND DISCUSSION: The detection rate for breathing [%] of MIM compared with the reference signal under CPAP was 88% [95% CI: (87.1%; 88.5%)], mechanical ventilation 91% [95% CI: (90.3%; 91.2%)] and under HFOV 95% [95% CI: (94.7%; 94.9%)]. For heart activity, during apnea the difference between MIM and reference signal was 1.1 bpm (+/-11.3 SD) in apnea and during HFOV 5.3 bpm (+/-26.4 SD). Under spontaneous breathing it was not possible to achieve a correlation. Owing to interference problems, registration of heart activity with MIM during simultaneous breathing activity (CPAP, conventional mechanical ventilation, HFOV) was insufficient. CONCLUSION: Non-contact monitoring of lung activity using MIM in a neonatal piglet model is possible under specific conditions. These results might be a basis for the development of non-invasive parameters in neonatology. It also provides the possibility of obtaining more information about the characteristics of lung activity of the newborn.

Ablation of articular cartilage with an erbium:YAG laser: an ex vivo study using porcine models under real conditions-ablation measurement and histological examination.

BACKGROUND AND OBJECTIVES: The use of an erbium:YAG laser in arthroscopic surgery has the advantage of a precise treatment of soft tissue. Due to the high absorption in water, the laser energy is perfectly matched to smoothing the hydrous, fibrillated articular cartilage surface. In minimal invasive surgery, the workspace is filled with aqueous liquids for enlargement. This appears contrary to the absorption characteristics of erbium:YAG laser radiation in water. The purpose of this study was to evaluate the ablated volume per pulse of cartilage lesions and the potential side effects including thermal damage and tissue necrosis. STUDY DESIGN/MATERIALS AND METHODS: Twenty-four osteochondral specimens of porcine knee joints were irradiated with an Er:YAG laser completely submerged in water, with distances to the cartilage surface of 1, 3 and 5 mm and pulse durations of 75 and 100 microseconds. To keep a constant peak power of approximately 6 kW, pulse energies of 450 and 580 mJ were used at a pulse repetition rate of 15 Hz. After a histological preparation, ablated volumes, depths, and widths of the cuts were investigated. Additionally, laser protocols were correlated with different markers of cartilage tissue damage and apoptosis. RESULTS: Ablation could be observed for every measurement. The influence of the distance showed a statistical significance (P < 0.001) for the volume, depth, and width of the cuts. For the pulse duration, statistical significance (P < 0.001) was found only for the volume and the depth. We observed no loss of proteoglycan or collagen type II. The total cell number, cell morphology, and number of apoptotic cells in an area close to the cutting edge and in a corresponding unaffected area of the same specimens revealed no differences regardless of the applied protocol. CONCLUSION: The use of an Er:YAG laser demonstrates the successful application in liquid environments for cartilage removal without any damage of the surrounding tissue.

Effects of preincubation temperature on the detection of fastidious organisms in delayed-entry samples in the BacT/ALERT 3D blood culture system.

This study evaluates the effect of preincubation on delayed-entry samples for fastidious organisms including the HACEK group, Streptococcus species, Neisseria meningitidis, Haemophilus species and Corynebacterium species for the BacT/ALERT 3D System (bioMérieux) using the FA (aerobic) medium. Bottles were inoculated with two different concentrations (0.5 McFarland and a 1:100,000 dilution) of each organism and either loaded into the system immediately or stored at 4 degrees C, room temperature (RT) or 37 degrees C for 24 hours (h) prior to loading. The detection rate (DR) was 92.5% for bottles loaded immediately for both concentrations with a mean time to detection (TTD) of 26.7 h (standard deviation (SD): 14.7 h) for the low concentration and 9.21 h (SD: 5.3 h) for the high concentration. Preincubation at 4 degrees C did not affect the DR for either of the two concentrations in comparison to no preincubation. The DR at RT was 90.0% for the low concentration and 83.6% for the high concentration. At 37 degrees C the DR was 76.3% and 66.3% for the low and the high concentrations respectively. The average TTD was inversely correlated with the preincubation temperature. An incubation of four days was sufficient, with the exception of Eikenella corrodens and Gemella sanguinis. The serotype of Streptococcus pneumoniae or Neisseria meningitidis did not influence the TTD. Kingella kingae remained undetected. For the retrieval of the above mentioned bacteria we recommend storage of bottles at room temperature. In case of erroneous storage at 37 degrees C subcultivation is advisable. All cases with a negative result on day four should be reevaluated and eventually new material for alternative diagnostic procedures should be retrieved.

The role of the composite interleukin-1 genotype in the association between periodontitis and acute myocardial infarction.

BACKGROUND: Recent data indicate that interleukin (IL)-1 polymorphism may influence the susceptibility to periodontitis and coronary heart diseases. The aim of this study was to evaluate the impact of the composite IL-1 genotype (allele 2 at IL-1A -889 and IL-1B +3954) in the association between acute myocardial infarction (AMI) and periodontitis. METHODS: One hundred four white subjects (54 patients with AMI and 50 healthy controls) were studied; each received a comprehensive periodontal examination, including measurement of periodontal probing depth (PD) and clinical attachment level (CAL). The extent of periodontitis was assessed by the percentage of sites with clinical AL >3 mm. Polymorphisms in the IL-1 gene cluster were assessed using a reverse hybridization assay. RESULTS: Compared to controls, mean values for PD (4.6 mm versus 3.7 mm; P <0.0001) and CAL (5.4 mm versus 4.5 mm; P = 0.0001) were significantly increased among patients with AMI. Significantly more subjects with moderate or severe periodontitis (> or =33% of sites with clinical AL >3 mm) were found in the AMI group compared to controls (31.5% versus 8%; P = 0.0016). These differences remained statistically significant after adjustment for smoking, age, and gender. No significant differences were observed in the allele frequencies of the gene loci IL-1A -889 and IL-1B +C3954 between patients with AMI and controls. Also, there was no difference in the frequency of the composite IL-1 genotype. IL-1 genotype-positive patients with AMI had slightly increased PD and AL compared to IL-1 genotype-negative patients with AMI. CONCLUSIONS: The results confirmed an association between periodontitis and AMI but failed to detect a modifying impact of the composite IL-1 genotype. Although the IL-1 genotype was only weakly associated with compromised periodontal health, it was not associated with AMI.

Spectral rhoZ-projection method for characterization of body fluids in computed tomography: ex vivo experiments.

RATIONALE AND OBJECTIVES: The identification of body fluids in computed tomography poses a major diagnostic challenge. The chemical composition of body fluids deviates only slightly from water with very similar computed tomographic (CT) values, which typically range from 0 to 100 HU. The aim of this study was to assess physical and chemical properties of different body fluids in an ex vivo setting. MATERIALS AND METHODS: A total of 44 samples of blood, blood mixed with pus, pus, bile, and urine obtained during diagnostic and therapeutic punctures were scanned at 80 and 140 kV. Data was quantitatively assessed using the spectral rhoZ-projection algorithm, which converts dual-energy CT scans into mass density (rho) and effective atomic number (Z(eff.)) information. RESULTS: Attenuation values measured at 80 and 140 kV were largely overlapping. CT values allowed, to some degree, for the differentiation of bile or pus from blood or the blood/pus mixture. By applying the rhoZ-projection, most substances, except for urine, were distinguishable with only small standard deviations ranging between 0.003 and 0.007 g/cm(3) for mass density and between 0.020 and 0.043 for Z(eff.). CONCLUSION: The rhoZ-projection method is suited to quantitatively assess mass density and effective atomic number of ex vivo body fluid samples. In clinical routine, this technique might be useful for identifying unclear fluid collections even in unenhanced computed tomography.

Association of fetuin-A levels with the progression of aortic valve calcification in non-dialyzed patients.

AIMS: Fetuin-A has been identified as a potent circulating inhibitor of ectopic calcification. We investigated the relationship between baseline fetuin-A serum levels and the rate of progression of aortic valve calcification (AVC) in non-dialyzed patients with aortic valve disease (AVD). METHODS AND RESULTS: Seventy-seven patients (mean age 70 +/- 8 years) with echocardiographically proven AVD were collected. In all patients, serum fetuin-A levels, creatinine, calcium, lipid parameters, and C-reactive protein were measured at baseline. For quantification of AVC progression, all patients underwent multislice spiral computed tomography examinations at baseline and after a mean follow-up of 12.6 +/- 1.4 months (range 7-18 months). In a multifactorial analysis of covariance including fetuin-A levels, baseline AVC score, the covariables sex, age, body mass index, C-reactive protein, glomerular filtration rate, serum lipids, diabetes, smoking status, and hypertension, only serum fetuin-A levels significantly predict the progression of AVC (P < 0.001). Post hoc analysis demonstrated that patients with baseline fetuin-A levels lower than the median of the cohort (0.72 g/L) showed a significantly higher increase of AVC scores (34.6 +/- 31.4%) than patients with fetuin-A levels larger than the median (10.0 +/- 11.2%, P < 0.001) despite comparable baseline AVC scores. In addition, fetuin-A levels were associated with major adverse clinical events (MACE; P = 0.03). CONCLUSION: Serum levels of the calcification inhibitor fetuin-A are associated with the progression of AVC and MACE, independent of the renal function and inflammation.