Advanced morphological 3D magnetic resonance observation of cartilage repair tissue (MOCART) scoring using a new isotropic 3D proton-density, turbo spin echo sequence with variable flip angle distribution (PD-SPACE) compared to an isotropic 3D steady-state free precession sequence (True-FISP) and standard 2D sequences

PURPOSE

To evaluate a new isotropic 3D proton-density, turbo-spin-echo sequence with variable flip-angle distribution (PD-SPACE) sequence compared to an isotropic 3D true-fast-imaging with steady-state-precession (True-FISP) sequence and 2D standard MR sequences with regard to the new 3D magnetic resonance observation of cartilage repair tissue (MOCART) score.

MATERIALS AND METHODS

Sixty consecutive MR scans on 37 patients (age: 32.8 ± 7.9 years) after matrix-associated autologous chondrocyte transplantation (MACT) of the knee were prospectively included. The 3D MOCART score was assessed using the standard 2D sequences and the multiplanar-reconstruction (MPR) of both isotropic sequences. Statistical, Bonferroni-corrected correlation as well as subjective quality analysis were performed.

RESULTS

The correlation of the different sequences was significant for the variables defect fill, cartilage interface, bone interface, surface, subchondral lamina, chondral osteophytes, and effusion (Pearson coefficients 0.514-0.865). Especially between the standard sequences and the 3D True-FISP sequence, the variables structure, signal intensity, subchondral bone, and bone marrow edema revealed lower, not significant, correlation values (0.242-0.383). Subjective quality was good for all sequences (P ≥ 0.05). Artifacts were most often visible on the 3D True-FISP sequence (P < 0.05).

CONCLUSION

Different isotropic sequences can be used for the 3D evaluation of cartilage repair with the benefits of isotropic 3D MRI, MPR, and a significantly reduced scan time, where the 3D PD-SPACE sequence reveals the best results.

Cartilage quality assessment by using glycosaminoglycan chemical exchange saturation transfer and (23)Na MR imaging at 7 T

PURPOSE

To compare a glycosaminoglycan chemical exchange saturation transfer (gagCEST) imaging method, which enables sampling of the water signal as a function of the presaturation offset (z-spectrum) at 13 points in clinically feasible imaging times, with sodium 23 ((23)Na) magnetic resonance (MR) imaging in patients after cartilage repair surgery (matrix-associated autologous chondrocyte transplantation and microfracture therapy).

MATERIALS AND METHODS

One female patient (67.3 years), and 11 male patients (median age, 28.8 years; interquartile range [IQR], 24.6-32.3 years) were examined with a 7-T whole-body system, with approval of the local ethics committee after written informed consent was obtained. A modified three-dimensional gradient-echo sequence and a 28-channel knee coil were used for gagCEST imaging. (23)Na imaging was performed with a circularly polarized knee coil by using a modified gradient-echo sequence. Statistical analysis of differences and Spearman correlation were applied.

RESULTS

The median of asymmetries in gagCEST z-spectra summed over all offsets from 0 to 1.3 ppm was 7.99% (IQR, 6.33%-8.79%) in native cartilage and 5.13% (IQR, 2.64%-6.34%) in repair tissue. A strong correlation (r = 0.701; 95% confidence interval: 0.21, 0.91) was found between ratios of signal intensity from native cartilage to signal intensity from repair tissue obtained with gagCEST or (23)Na imaging. The median of dimensionless ratios between native cartilage and repair tissue was 1.28 (IQR, 1.20-1.58) for gagCEST and 1.26 (IQR, 1.21-1.48) for (23)Na MR imaging.

CONCLUSION

The high correlation between the introduced gagCEST method and (23)Na imaging implies that gagCEST is a potentially useful biomarker for glycosaminoglycans.

Microcoil-based MRI: feasibility study and cell culture applications using a conventional animal system

OBJECT

The aim of this study was to demonstrate the feasibility of MR microimaging on a conventional 9.4 T horizontal animal MRI system using commercial available microcoils in combination with only minor modifications to the system, thereby opening this field to a larger community.

MATERIALS AND METHODS

Commercially available RF microcoils designed for high-resolution NMR spectrometers were used in combination with a custom-made probehead. For this purpose, changes within the transmit chain and modifications to the adjustment routines and image acquisition sequences were made, all without requiring expensive hardware. To investigate the extent to which routine operation and high-resolution imaging is possible, the quality of phantom images was analysed. Surface and solenoidal microcoils were characterized with regard to their sensitive volume and signal-to-noise ratio. In addition, the feasibility of using planar microcoils to achieve high-resolution images of living glioma cells labelled with MnCl(2) was investigated.

RESULTS

The setup presented in this work allows routine acquisition of high-quality images with high SNR and isotropic resolutions up to 10 μm within an acceptable measurement time.

CONCLUSION

This study demonstrates that MR microscopy can be applied at low cost on animal MR imaging systems, which are in widespread use. The successful imaging of living glioma cells indicates that the technique promises to be a useful tool in biomedical research.

IL10 promoter polymorphisms are associated with systemic onset juvenile idiopathic arthritis (SoJIA)

OBJECTIVES

Juvenile idiopathic arthritis (JIA) is a rare, but severe cause of childhood disability. Systemic onset JIA (SoJIA) accounts for approximately 5.8% of all JIA cases and is associated with cytokine dysregulation, including interleukin (IL-)1, IL-6 and tumour necrosis factor (TNF-)α. IL-10 is an immuno-regulatory cytokine, which in part regulates inflammation by controlling inflammatory cytokine expression. Dysregulation in IL-10 expression and certain single nucleotide polymorphisms (SNPs) in the IL-10 promoter were shown to be associated with autoimmune and infectious diseases.

METHODS

Genomic DNA-samples from SoJIA patients from two German Paediatric Rheumatology centres, and healthy controls were analysed for three well defined IL-10 promoter SNPs (-1082G>A, -819C>T, and -592C>A). These SNPs are in tight linkage disequilibrium, and result in three predominant (or 'classical') haplotypes: ATA, ACC, and GCC. ATA and ACC are associated with low and medium, GCC is associated with high IL-10 expression.

RESULTS

Here, we show a strong association of IL-10 promoter polymorphisms with SoJIA. We demonstrate a significantly increased frequency of low IL-10 expressing -1082A/A alleles, the medium IL-10 expressing ACC haplotype (p=0.01), and an enrichment of the rare GTC haplotype (p<0.001) in patients with SoJIA. Heterozygous -1082G/A alleles (p<0.001), and the GCC haplotype (p<0.001) on one allele protect from developing SoJIA.

CONCLUSIONS

This suggests a central role of the immuno-regulatory cytokine IL-10 in the pathogenesis of SoJIA.

In vivo diffusion tensor magnetic resonance imaging and fiber tracking of the mouse brain

Until very recently, the study of neural architecture using fixed tissue has been a major scientific focus of neurologists and neuroanatomists. A non-invasive detailed insight into the brain's axonal connectivity in vivo has only become possible since the development of diffusion tensor magnetic resonance imaging (DT-MRI). This unique approach of analyzing axonal projections in the living brain was used in the present study to describe major white matter fiber tracts of the mouse brain and also to identify for the first time non-invasively the rich connectivity between the amygdala and different target regions. To overcome the difficulties associated with high spatially and temporally resolved DT-MRI measurements a 4-shot diffusion weighted spin echo (SE) echo planar imaging (EPI) protocol was adapted to mouse brain imaging at 9.4T. Diffusion tensor was calculated from data sets acquired by using 30 diffusion gradient directions while keeping the acquisition time at 91 min. Two fiber tracking algorithms were employed. A deterministic approach (fiber assignment by continuous tracking - FACT algorithm) allowed us to identify and generate the 3D representations of various neural pathways. A probabilistic approach was further used for the generation of probability maps of connectivity with which it was possible to investigate - in a statistical sense - all possible connecting pathways between selected seed points. We show here applications to determine the connection probability between regions belonging to the visual or limbic systems. This method does not require a priori knowledge about the projections' trajectories and is shown to be efficient even if the investigated pathway is long or three-dimensionally complex. Additionally, high resolution images of rotational invariant parameters of the diffusion tensor, such as fractional anisotropy, volume ratio or main eigenvalues allowed quantitative comparisons in-between regions of interest (ROIs) and showed significant differences between various white matter regions.

3 ANALYSIS OF HOX EXPRESSION IN BOVINE OOCYTES AND EARLY EMBRYOS

HOX genes encode transcription factors known to play a major role in patterning the main body axis of vertebrate embryos from the gastrulation stage onward. A few studies have provided evidence that some HOX genes might be expressed before implantation in mammalian embryos. Translation of maternally inherited transcripts is regulated by modifications of the poly(A) tail length until embryonic genome activation (EGA), occurring during the 4th cell cycle in the bovine. The objective of this work was to establish the expression pattern of various HOX genes and to study the polyadenylation of their transcripts during oocyte maturation and early embryonic development. Pools of 20 bovine oocytes before and after in vitro maturation and 20 in vitro-produced embryos at different stages of development up to the blastocyst stage were collected. Three to 12 pools were used for each stage. RNA was extracted and reverse transcribed (RT) using random hexamers. Quantitative real-time PCR (qPCR) was performed to establish expression profiles of 4 HOX genes: HOXD1, HOXA3, HOXB9, and HOXC9. Two distinct patterns of expression were observed. First, relative amounts of HOXD1, HOXA3, and HOXC9 were lower in morulae and blastocysts than in oocytes. On the other hand, relative expression of HOXB9 increased between the 5 to 8 cell stage and the morula stage (Mann-Whitney, P < 0.05). Those expression patterns were not modified when embryos were cultured in presence of α-amanitin, a RNA polymerase II inhibitor, indicating the maternal origin of the transcripts until EGA. Total amount of mRNAs, estimated by RT-qPCR with random hexamers, was stable for all studied genes during oocyte maturation. The relative amount of polyadenylated GAPDH mRNAs, estimated by RT-qPCR with poly(dT), decreased greatly in mature oocytes compared with immature oocytes indicating massive deadenylation of those transcripts. The relative amount of polyadenylated HOXC9 transcripts decreased slightly but significantly during oocyte maturation (Mann-Whitney, P < 0.05).The relative amount of polyadenylatedm RNAs corresponding to HOXD1, HOXA3, and HOXB9 was stable during oocyte maturation. This indicates that those transcripts escape the default deadenylation pathways followed by housekeeping genes. This experiment has been repeated 3 to 4 times. In conclusion, we confirmed the presence of HOXD1, HOXA3, HOXB9, and HOXC9 transcripts in bovine oocytes and early-stage embryos. Their role during oocyte maturation and the first stages of embryonic development will be investigated through loss of function studies. This work is funded by the Fonds National de la Recherche Scientifique (Belgium).

Cardiac Safety Results of a Phase II Trial of Adjuvant Docetaxel/Cyclophosphamide Plus Trastuzumab (Her TC) in HER2+ Early Stage Breast Cancer Patients

Background: Docetaxel/cyclophosphamide (TC) has superior activity to doxorubicin/cyclophosphamide (AC) in the adjuvant treatment of patients (pts) with early breast cancer and is devoid of known cardiac toxicity (Jones et al, JCO 27:1177-1183, 2009). Although the addition of trastuzumab (H) to anthracycline-based adjuvant regimens is effective, it is associated with increased cardiac toxicity. Therefore, a short course of the nonanthracycline TC regimen coupled with H appeared to be a logical combination for women with lower risk HER2+ breast cancer. We report the cardiac safety of the TC+H regimen for the first group of women to complete 1 year of treatment.Patients and Methods: 263 pts were registered to the study and stratified by nodal status (positive/negative). Pts must have had baseline left ventricular ejection fraction (LVEF) ≥50% by MUGA or ECHO. On Day 1 of each 21-day cycle for a total of 4 cycles, pts received: (T) 75 mg/m2 IV, followed by (C) 600 mg/m2 IV. Weekly (H) was also given at 4 mg/kg IV (loading dose, over 90 minutes Day 1, Cycle 1 only) and 2 mg/kg IV Days 1, 8, 15 thereafter throughout chemotherapy. After completion of chemotherapy, H was administered at 6 mg/kg IV every 3 weeks to complete 12 months of therapy with H. Decreased LVEF was defined as a decrease from baseline (start of treatment) to completion of TC+H, or when assessed at 3-month intervals until the completion of H treatment. H was withheld if there was a 15% or more decline in LVEF (absolute %). Treatment was discontinued after 2 or 3 treatment delays at investigator's discretion (same rules as prior studies). This report focuses on cardiac safety occurring during the 3 months of chemotherapy plus 1 year of H therapy.Results: To date, 260 pts completed 1 year of treatment and comprised the cardiac safety population; median age was 55 yrs (30-76); 90% of pts had ECOG 0; 64% were ER+, 47% were PR+, and 77% had no lymph node involvement. 184 pts (70%) completed planned treatment and 23 pts (9%) discontinued treatment due to adverse events. A total of 61 pts (23.5%) had declines of ≥10% LVEF; 8 pts (3.1%) had 2 or more LVEF declines ≥10% and were taken off treatment before 1 year of H was completed, and 16 pts (6.1%) had declines of LVEF below 50% during treatment. No patient had clinical CHF.Scheduled MUGA/ECHO ResultsMonthPatients, no.Median LVEF, % (range)Patients with decrease LVEF ≥10%, no.Patients with LVEF &lt;50%, no.Baseline26064 (49,89)––1-324163 (40,85)154-623062 (40,85)2157-921763 (36,89)265≥1018763 (48,80)131Conclusions: H combined with 4 cycles of the nonanthracycline TC regimen produced a low rate of cardiac events, mainly asymptomatic drops in LVEF, but no reported cases of CHF.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5082.

Cerebral correlates of heart rate variations during a spontaneous panic attack in the fMRI scanner

We report the first published case study of a suddenly occurring panic attack in a patient with no prior history of panic disorder during combined functional magnetic resonance imaging (fMRI, 1.5 Tesla) and electrocardiogram (ECG) recording. The single case was a 46-year-old woman who developed a panic attack near the planned end of the fMRI acquisition session, which therefore had to be aborted. Correlational analysis of heart rate fluctuations and fMRI data revealed a significant negative association in the left middle temporal gyrus. Additionally, regions-of-interest (ROI) analyses indicated significant positive associations in the left amygdala, and trends towards significance in the right amygdala and left insula.

A 24-month subgroup analysis of the effect of denosumab on bone mineral density in women with breast cancer undergoing aromatase inhibitor therapy

Abstract #2106

Background: Accelerated bone loss and fracture risk are expected consequences of adjuvant aromatase inhibitor (AI) therapy. We previously showed that denosumab, a fully human monoclonal antibody that inhibits RANK ligand (RANKL), significantly increased bone mineral density (BMD) at the lumbar spine and at all measured skeletal sites at 12 months compared with placebo in women with breast cancer undergoing adjuvant AI therapy (Ellis et al, 2007 SABCS). In this analysis, we assessed covariates that may influence treatment effects on BMD at the lumbar spine, total hip, femoral neck, and 1/3 radius at 24 months.&#x2028; Methods: Adult patients (pts) with hormone receptor-positive breast cancer, who had evidence of low bone mass and were receiving adjuvant AI therapy, were enrolled in this randomized, double-blind, placebo-controlled, phase 3 study. Pts were stratified according to length of previous AI therapy (≤ 6 vs &gt; 6 months) and randomly assigned to receive, together with calcium and vitamin D, placebo (n=125) or denosumab 60 mg (n=127) subcutaneously every 6 months for 4 doses. Subgroup analysis was conducted using analysis of covariance and adjusted for treatment, stratification factor, baseline BMD value, densitometer type, and baseline BMD value-by-densitometer-type interaction.&#x2028; Results: At 24 months, greater increases in BMD were seen at all measured skeletal sites (both trabecular and cortical bone) for denosumab compared with placebo, regardless of the subgroup (table). Adverse events (AEs) occurred at a similar rate in both groups (91% denosumab, 90% placebo).&#x2028; Conclusion: In pts with breast cancer undergoing adjuvant AI therapy, twice-yearly denosumab treatment showed consistent increases in BMD across the skeleton at 24 months compared with placebo, regardless of subgroups.&#x2028; &#x2028;

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2106.