Search

Diffuse optical spectroscopy (DOS) may be advantageous for monitoring tumor response during chemotherapy treatment, particularly in the early treatment stages. In this paper we perform a second analysis on the data of a clinical trial with 25 breast cancer patients that received neoadjuvant chemotherapy. Patients were monitored using delayed contrast enhanced MRI and additionally with diffuse optical spectroscopy at baseline, after 1 cycle of chemotherapy, halfway therapy and before surgery. In this analysis hemoglobin content between tumor tissue and healthy tissue of the same breast is compared on all four monitoring time points. Furthermore, the predictive power of the tumor-healthy tissue difference of HbO2 for non-responder prediction is assessed. The difference in HbO2 content between tumor and healthy tissue was statistically significantly higher in responding tumors than in non-responding tumors at baseline (10.88 vs -0.57 μM, P=0.014) and after one cycle of chemotherapy (6.45 vs -1.31 μM, P=0.048). Before surgery this difference had diminished. In the data of this study, classification on the HbO2 difference between tumor and healthy tissue was able to predict tumor (non-)response at baseline and after 1 cycle with an area-under-curve of 0.95 and 0.88, respectively. While this result suggests that tumor response can be predicted before chemotherapy onset, one should be very careful with interpreting these results. A larger patient population is needed to confirm this finding.

Purpose: Diffuse optical spectroscopy (DOS) has the potential to enable monitoring of tumor response during chemotherapy, particularly in the early stages of treatment. This study aims to assess feasibility of DOS for monitoring treatment response in HER2-negative breast cancer patients receiving neoadjuvant chemotherapy (NAC) and compare DOS with tumor response assessment by MRI. Experimental Design: Patients received NAC in six cycles of 3 weeks. In addition to standard treatment monitoring by dynamic contrast enhanced MRI (DCE-MRI), DOS scans were acquired after the first, third, and last cycle of chemotherapy. The primary goal was to assess feasibility of DOS for early assessment of tumor response. The predictive value of DOS and DCE-MRI compared with pathologic response was assessed. Results: Of the 22 patients, 18 patients had a partial or complete tumor response at pathologic examination, whereas 4 patients were nonresponders. As early as after the first chemotherapy cycle, a significant difference between responders and nonresponders was found using DOS (HbO2 86% ± 25 vs. 136% ± 25, P = 0.023). The differences between responders and nonresponders continued during treatment (halfway treatment, HbO2 68% ± 22 vs. 110% ± 10, P = 0.010). Using DCE-MRI, a difference between responders and nonresponders was found halfway treatment (P = 0.005) using tumor volume measurement calculations. Conclusions: DOS allows for tumor response assessment and is able to differentiate between responders and nonresponders after the first chemotherapy cycle and halfway treatment. In this study, DOS was equally effective in predicting tumor response halfway treatment compared with DCE-MRI. Therefore, DOS may be used as a novel imaging modality for (early) treatment monitoring of NAC. Clin Cancer Res; 21(3); 577–84. ©2014 AACR.

Background: In autosomal dominant polycystic kidney disease (ADPKD), obtaining measured total kidney volume (mTKV) by magnetic resonance (MR) imaging and manual tracing is time consuming. Two alternative MR imaging methods have recently been proposed to estimate TKV (eTKV(ellipsoid) and eTKV(PANK)), which require less time.Study Design: Cross-sectional and longitudinal diagnostic test study.Setting & Participants: Patients with ADPKD with a wide range of kidney function and an approved T2-weighted MR image obtained at the University Medical Centers of Groningen, Leiden, Nijmegen, and Rotterdam, the Netherlands, in 2007 to 2014. Test set for assessing reproducibility, n = 10; cohort for cross-sectional analyses, n = 220; and cohort for longitudinal analyses, n = 48.Index Tests: Average times for eTKV(ellipsoid) and eTKV(PANK) were 5 and 15 minutes, respectively. Bias is defined as (mTKV - eTKV)/mTKV x 100%; precision, as one standard deviation of bias.Reference Tests: mTKV using manual tracing to calculate the area within kidney boundaries times slice thickness. Average time for mTKV was 55 minutes.Results: In the test set, intra- and intercoefficients of variation for mTKV, eTKV(ellipsoid), and eTKV(PANK) were 1.8% and 2.3%, 3.9% and 6.3%, and 3.0% and 3.4%, respectively. In cross-sectional analysis, baseline mTKV, eTKV(ellipsoid), and eTKV(PANK) were 1.96 (IQR, 1.28-2.82), 1.93 (IQR, 1.25-2.82), and 1.81 (IQR, 1.17-2.62) L, respectively. In cross-sectional analysis, bias was 0.02% +/- 3.2%, 1.4% +/- 9.2%, and 4.6% +/- 7.6% for repeat mTKV, eTKV(ellipsoid), and eTKV(PANK), respectively. In longitudinal analysis, no significant differences were observed between percentage change in mTKV (16.7% +/- 17.1%) and percentage change in eTKV(ellipsoid) (19.3% 6 16.1%) and eTKV(PANK) (17.8% +/- 16.1%) over 3 years.Limitations: Results for follow-up data should be interpreted with caution because of the limited number of patients.Conclusions: Both methods for eTKV perform relatively well compared to mTKV and can detect change in TKV over time. Because eTKV(ellipsoid) requires less time than eTKV(PANK), we suggest that this method may be preferable in clinical care. (C) 2015 by the National Kidney Foundation, Inc.

Contains fulltext : 151967.pdf (Publisher’s version ) (Open Access)

To assess the feasibility of quantifying functional renal volume with gadolinium-enhanced magnetic resonance (MR) angiography.Institutional review board approval was obtained, and all subjects gave informed consent. A contour-detection three-dimensional algorithm for determining renal volumes was developed. The method was validated in 18 cadaveric pig kidneys by measuring the water displacement caused by the kidneys. The kidney lengths and volumes in 19 consecutive potential kidney donors who underwent gadolinium-enhanced MR angiography of the renal arteries also were determined. Differences in volume measurements between men and women and between left and right kidneys were analyzed by using the Student t test. The volume of perfused renal cortex was calculated by extracting voxels on the basis of the cortex signal intensity threshold. The relevance of renal function parameters--namely, creatinine clearance rates--in the donor candidates was assessed by using a linear regression model. Intra- and interobserver variabilities of the measurements were determined by using the Bland-Altman method.Volume measurements of the cadaveric pig kidneys obtained by using MR angiography and the water displacement method were strongly correlated (r = 0.99). The mean total renal volume in the donor candidates was 196 mL (range, 136-295 mL). No significant differences in total renal volume between the men and women or between the left and right kidneys were found. The correlation between calculated renal cortex volumes (mean, 67 mL; range, 40-105 mL) and creatinine clearance rates was good (r = 0.69). Inter- and intraobserver variabilities were lower than 7%.Quantification of functional renal volume with three-dimensional gadolinium-enhanced MR angiography seems feasible with use of the described semiautomatic method.

Steady state and laser flash photolysis studies of the heme/non-heme mu-oxo diiron complex [((6)L)Fe(III)-O-Fe(III)-Cl](+) (1) have been undertaken. The anaerobic photolysis of benzene solutions of 1 did not result in the buildup of any photoproduct. However, the addition of excess triphenylphosphine resulted in the quantitative photoreduction of 1 to [((6)L)Fe(II)...Fe(II)-Cl](+) (2), with concomitant production by oxo-transfer of 1 equiv of triphenylphosphine oxide. Under aerobic conditions and excess triphenylphosphine, the reaction produces multiple turnovers (approximately 28) before the diiron complex is degraded. The anaerobic photolysis of tetrahydrofuran (THF) or toluene solutions of 1 likewise results in the buildup of 2. The oxidation products from these reactions included gamma-butyrolactone (approximately 15%) for the reaction in THF and benzaldehyde (approximately 23%) from the reaction in toluene. In either case, the O-atom which is incorporated into the carbonyl product is derived from dioxygen present under workup or under aerobic photolysis conditions. Transient absorption measurements of low-temperature THF solutions of 1 revealed the presence of an (P)Fe(II)-like [P = tetraaryl porphyrinate dianion] species suggesting that the reactive species is a formal (heme)Fe(II)/Fe(IV)=O(non-heme) pair. The non-heme Fe(IV)=O is thus most likely responsible for C-H bond cleavage and subsequent radical chemistry. The photolysis of 1 in chlorobenzene or 1,2-dichlorobenzene resulted in C-Cl cleavage reactions and the formation of [[((6)L)Fe(III)-Cl...Fe(III)-Cl](2)O](2+) (3), with chloride ligands that are derived from solvent dehalogenation chemistry. The resulting organic products are biphenyl trichlorides or biphenyl monochlorides, derived from dichlorobenzene and chlorobenzene, respectively. Similarly, product 3 is obtained by the photolysis of benzene-benzyl chloride solutions of 1; the organic product is benzaldehyde (approximately 70%). A brief discussion of the dehalogenation chemistry, along with relevant environmental perspectives, is included.

To assess the effects of changing analytic method variables on the signal intensity (SI) difference-to-noise ratios (SDNRs) for the contrast between lesions and background organs depicted on magnetic resonance (MR) images and to propose a standardized analytic method for the quantitative analysis of focal masses seen at MR imaging.The SIs of 48 liver metastases (originating from colorectal cancer) in 20 patients, the surrounding liver parenchyma, and the background noise were measured on T2-weighted MR images. All 2000 and 2001 issues of the American Journal of Roentgenology, the Journal of Magnetic Resonance Imaging, Magnetic Resonance Imaging, and Radiology were searched for articles describing quantitative analyses. SDNRs were calculated by using formulas from these articles and various region-of-interest (ROI) locations to measure metastasis and background noise SIs. The Wilcoxon signed rank test was used to compare the various SDNR calculations.In 34 articles in which quantitative analyses of focal masses are described, the reported SDNRs were calculated with four different formulas. The SDNRs for our study material calculated with the four formulas reported in the literature differed grossly in both number and unit. The SDNRs for ROIs encompassing the entire metastasis differed significantly (P =.034) from the SDNRs for ROIs in a homogeneous area of the metastasis margin. Differences in SDNRs between various noise ROI locations were significant (P.022).Slight changes in the variables of quantitative analysis of focal masses had marked effects on reported SDNRs. To overcome these effects, the use of a standardized method involving one formula, a lesion ROI in a homogeneous area at the metastasis margin, and a background noise ROI along the phase-encoding axis in the air (including systematic noise) is proposed for the quantitative analysis of findings on magnitude MR images.

To compare soft- and hard-copy computed tomographic (CT) image interpretation with regard to evaluation time and detection rates for hepatic and extrahepatic colorectal metastases in candidates for liver surgery.In 20 patients with a history of colorectal carcinoma, two radiologists independently evaluated CT data sets. Focal hepatic lesions were characterized as benign or malignant by using a five-point scale. In each patient, soft-copy readouts and hard-copy printouts were compared for nonenhanced hepatic, contrast material-enhanced hepatic, and contrast-enhanced extrahepatic data sets. A stopwatch was used to document evaluation time. Ninety-two hepatic metastases and six extrahepatic metastatic recurrences were detected with the standard of reference--surgical, intraoperative ultrasonographic, and histologic findings.Both observers evaluated the contrast-enhanced hepatic data set significantly faster (P =.026 and.009) by using soft-copy readouts. The contrast-enhanced extrahepatic data set was also evaluated significantly faster (P =.010 and.006) with soft-copy readouts. Detection of hepatic and extrahepatic tumor with soft-copy readouts is not significantly superior to that with hard copies. Detection rates of hepatic metastases for nonenhanced and contrast-enhanced CT for both observers ranged from 50%-80% (46-74 of 92) for soft-copy readouts and 46%-75% (42-69 of 92) for hard copies. Interobserver agreement was highest for contrast-enhanced soft-copy readouts for hepatic metastases.Soft-copy readouts of contrast-enhanced CT data sets for the detection of hepatic metastases and extrahepatic metastatic recurrences were evaluated significantly faster than were hard copies, with at least equal sensitivity and with excellent interobserver agreement.

The O 2 -reaction chemistry of 1:1 mixtures of (F 8 )Fe II (1; F 8 = tetrakis(2,6-diflurorophenyl)porphyrinate) and [(L Me 2 N )Cu I ] + (2; L Me 2 N = N , N -bis{2-[2-( N ′, N ′-4-dimethylamino)pyridyl]ethyl}methylamine) is described, to model aspects of the chemistry occurring in cytochrome c oxidase. Spectroscopic investigations, along with stopped-flow kinetics, reveal that low-temperature oxygenation of 1/2 leads to rapid formation of a heme-superoxo species (F 8 )Fe III -(O \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} \begin{equation*}{\mathrm{_{2}^{-}}}\end{equation*}\end{document} ) (3), whether or not 2 is present. Complex 3 subsequently reacts with 2 to form [(F 8 )Fe III –(O \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} \begin{equation*}{\mathrm{_{2}^{2-}}}\end{equation*}\end{document} )–Cu II (L Me 2 N )] + (4), which thermally converts to [(F 8 )Fe III –(O)–Cu II (L Me 2 N )] + (5), which has an unusually bent (Fe–O–Cu) bond moiety. Tridentate chelation, compared with tetradentate, is shown to dramatically lower the ν(O–O) values observed in 4 and give rise to the novel structural features in 5.

To determine the relationship between the size of hepatic metastases, the standard of reference, and the reported detection rate in patients with colorectal cancer.With use of a MEDLINE search (January 1994 to January 2001), articles were selected that contained original results on detection of hepatic metastases of colorectal cancer, categorized for size in at least two categories, with use of helical computed tomography (CT), helical CT at arterial portography, or magnetic resonance imaging. Results were compared with the size distribution of hepatic metastases in 47 consecutive patients with colorectal carcinoma, which were detected by using a combination of intraoperative ultrasonography (US) and palpation.Seven studies met all predefined criteria. Four studies involved intraoperative US in all patients and demonstrated a significant negative correlation (-0.988) between detection rate and fraction of small metastases. These studies had a higher fraction and lower detection rate of small metastases and a lower overall detection rate. A majority (58% [145 of 252]) of metastases in the study population were smaller than 20 mm.Few articles adequately describe the standard of reference and size distribution of hepatic lesions. Hepatic metastases of colorectal cancer are frequently smaller than 20 mm. When the standard of reference is suboptimal, many small metastases are excluded from analysis, and detection rates are therefore inflated.

Reaction of FvW2(H)2(CO)6 with 2/8S8 in THF results in rapid and quantitative formation of FvW2(SH)2(CO)6. The crystal structure of this complex is reported and shows that the two tungsten−hydrosul...

Irradiation (λmax = 300−375 nm) of FvRu2(CO)4 (1, Fv = η5:η5-bicyclopentadienyl) or (μ2-η1:η5-cyclopentadienyl)2Ru2(CO)4 (2) with dimethyl cis- or trans-butenedioate resulted in FvRu2(η2-trans-CHRCHR)(CO)3 (3, R = CO2CH3). Prolonged irradiation of 1−3 provided FvRu2(η2-trans-CHRCHR)2(CO)2 (4a, R = CO2CH3) and FvRu2(η2-cis-CHRCHR)(η2-trans-CHRCHR)(CO)2 (4b, R = CO2CH3). Photocatalytic isomerization of cis to trans alkene occurred in the presence of 1−4. Irradiation of 1−3 with dimethyl butynedioate produced FvRu2(μ2-η2-dimethyl butynedioate)(CO)3 (5). Prolonged irradiation of 1−5 with the alkyne afforded FvRu2(μ2-η2:η4-CRCRCRCR)2(CO) (6, R = CO2CH3). Irradiation of a THF solution of 6 generated FvRu2(μ2-η2:η4-CRCRCRCR)2(THF) (7, R = CO2CH3). Photochemical alkyne cyclotrimerization was observed in the presence of 1−7. In the presence of CO, 7 reverted to 6 thermally. Heating 7 in the presence of dimethyl cis-butenedioate, thiophene, PPh3, or dimethyl sulfoxide (DMSO) afforded FvRu2(μ2-η2:η4-CRCRCRCR)2(L) (8...

To compare the effectiveness of different imaging planes at time-of-flight (TOF) magnetic resonance (MR) angiography and phase-contrast MR angiography in the visualization of the normal intracranial venous system.In 12 healthy volunteers, two-dimensional (2D) TOF MR angiography and three-dimensional (3D) phase-contrast MR angiography were performed in transverse, sagittal, and coronal planes. All data were displayed as maximum intensity projection (MIP) images. Four neuroradiologists assessed the visibility of 28 intracranial venous structures on the MIP images. Statistical analysis was performed by using the Friedman two-way analysis of variance and the Cochran Q test.Visualization of the normal intracranial venous system was better with 3D phase-contrast and coronal 2D TOF MR angiography than with transverse or sagittal 2D TOF MR angiography (P.05, Friedman test) for each observer and the group of observers. Differences were found between each of the 2D TOF and 3D phase-contrast MR angiographic sequences in the visualization of individual venous structures (Cochran Q test). The kappa values ranged from 0.36 to 0.71, which indicated a moderate to good agreement between observers.The normal intracranial venous system is adequately visualized with 3D phase-contrast and coronal 2D TOF MR angiography.

In this study, a T1-weighted three-dimensional (3D) spoiled gradient-echo scanning protocol was developed to image the complete arterial system of the pelvis and both legs along their entire length in patients with peripheral arterial disease. Three adjacent stations were to be acquired consecutively, with some overlap, to image the entire area of interest; per station one gadolinium (Gd) contrast bolus would be administered. In an in vitro phantom study, the scanning protocol was optimized. The optimal flip angle was found to be 50°. Also, the optimal scan delay was chosen to be equal to the arrival time of the contrast bolus, thereby minimizing artifacts. Three contrast bolus injections showed sufficient enhancement of the vessels after image subtraction. Finally, stenosis quantification by manual caliper was performed by five observers in the magnetic resonance angiography (MRA) images and correlated with the percent diameter reduction determined by quantitative angiography from corresponding X-ray images. The MRA measurements were reproducible, and intra- and interobserver variabilities were statistically non-significant (p = 0.54 and p = 0.12, respectively). Stenosis quantification performed by four observers showed a good correlation with the X-ray-derived values (rP > 0.90, p < 0.02); the results from one observer were not significantly correlated. Five patients with proven peripheral disease were investigated with this new MRA scanning protocol, using standard hardware and software. The images were of good quality, which allowed adequate clinical evaluation; the original diagnoses obtained from X-ray examinations, were confirmed with MRA. In conclusion, peripheral arterial disease can be evaluated adequately with this magnetic resonance scanning protocol.

The title compound [Cp 5 CpMn(CO) 3 ], 1 , has been characterized by X-ray crystallography and shown by laser-induced desorption/ionization (LDI) to undergo dissociative coalescence to fullerene C 60 and other carbon clusters.

In this study, a scanning protocol was developed to image the arterial bed of the pelvis and both legs along their entire length in patients with peripheral arterial disease, using standard hard-and software. Three adjacent stations are acquired consecutively, with some small overlap; per station; one Gadolinium contrast bolus is administered. The scanning protocol was optimized in an in vitro phantom study. The optimal flip angle was found to be 50°. Also, the optimal scan delay was chosen to be equal to the arrival time of the contrast bolus thereby minimizing artifacts. Three contrast bolus injections showed sufficient enhancement of the vessels after image subtraction. Finally, stenosis quantification by manual caliper was performed by five observers in the MRA images and correlated with the percent diameter reduction determined by quantitative angiography from corresponding X-ray images. The results of the MRA measurements were reproducible and intra- and inter-observer variabilities were statistically non-significant (p = 0.54 and p = 0.12, respectively). Stenosis quantification performed by four observers showed a good correlation with the X-ray derived values (r p > 0.90, p < 0.02); the results from one observer were not significantly correlated. Five patients with proven peripheral disease were investigated with this new MRA scanning protocol. The images were of good quality which allowed adequate clinical evaluation; the original diagnoses obtained from X-ray examinations, were confirmed with MRA. In conclusion, peripheral arterial disease can be evaluated adequately with this MR scanning protocol.

In this study a semi-automated and observer-independent algorithm for quantifying post-stenotic signal loss (PSL) in 3D phase-contrast (PC) magnetic resonance angiography (MRA) of patients with renal artery stenosis is presented. This algorithm was developed on MRA datasets of stenotic phantoms, which were included in a flow circuit with stationary flows. The length and the severity of the PSL (incorporating both length and degree of PSL) in the maximum intensity projections (MIPs) of MRA datasets were proposed for quantifying stenoses. The algorithm was tested in renal arteries of ten patients with renal artery stenosis and seven healthy volunteers. Digital subtraction angiography (DSA) was performed in the patients and served as the gold standard. Stenosis severity showed better correlation with the severity of the PSL than with the length, both for in vitro as in vivo. Spearman correlation coefficients (rS) showed statistically significant correlations between the severity of the PSL and parameters determined by DSA, i.e. percent diameter stenosis (rS = 0.90). The length of the PSL showed no correlation with the diameter stenosis (rS = 0.37).

Purpose: To investigate the value of superior mesenteric artery (SMA) Doppler flow measurements as a marker for disease activity in patients with Crohn's disease. Materials and Methods: Duplex Doppler sonographic measurements of SMA bloodflow volume were obtained in 90 patients with suspected or known Crohn's disease in three separate studies. The first study was a pilot study to ascertain the value of Doppler measurements in patients with proven active or inactive disease and to check our performance. In two following studies prospectively a correlation was sought between the independent assessment of Doppler flow measurements and our standard of reference based on clinical history, physical examination, laboratory values, endoscopy, surgery and/or follow-up and prospectively a correlation was sought between Doppler studies and the results of enteroclysis. Results: In all but two patients (study II) adequate measurements of SMA flow were obtained. In the active patient groups the Doppler SMA flow was significantly increased (P

A varying percentage of cadaveric transplant recipients remain anuric or oliguric and depend on dialysis in the first weeks after transplantation. This delayed graft function group needs careful management to detect additional post-transplant events. Under these clinical circumstances, the assessment of allograft status depends to a great extent on non-invasive imaging studies. The wide variety of imaging procedures for the transplanted kidney, combined with recent technical advances in ultrasonography, scintigraphy and radiopharmaceuticals, computed tomography and magnetic resonance imaging, has created a challenging and sometimes confusing environment for clinicians, radiologists and nuclear medicine physicians. Assessing the relative merits of available procedures and choosing an optimal approach to the clinical presentation of a particular graft is sometimes difficult. The contrasting characteristics of these diagnostic methods led us to consider their relative roles and to determine their selective use. This review focuses on the value and limitations of diagnostic imaging modalities in the management of patients with impaired or delayed graft function. Our emphasis is on ultrasonography and nuclear medicine, as these are the most frequently used methods.

In this study a semi-automated and observer-independent algorithm for quantifying post-stenotic signal loss (PSL) in three-dimensional phase-contrast (PC) magnetic resonance angiography (MRA) of patients with renal artery stenosis is presented. This algorithm was developed on MRA datasets of stenotic phantoms, included in a flow circuit with stationary flows. The length and the severity of the PSL (incorporating both the length and the degree of PSL) in the MRA datasets were proposed for quantifying the stenoses. The algorithm was tested in renal arteries; ten patients with renal artery stenosis and seven healthy volunteers were investigated. Digital subtraction angiography was performed in the patients and served as the gold standard. Stenosis severity showed better correlation with the severity of the PSL than with the length, both for in vitro and in vivo measurements. Spearman correlation coefficients (rs) showed statistically significant correlations between the severity of the PSL and parameters determined by digital subtraction angiography, i.e., percent diameter stenosis (rs = 0.90). The length of the PSL showed no correlation with the diameter stenosis (rs = 0.37). In conclusion, this study presents a semi-automated and observer-independent way of quantifying signal loss, and the severity of the PSL is proposed for quantifying stenoses, rather than the length of PSL.

To assess the value of measurements of superior mesenteric artery flow using Doppler ultrasound for detecting disease activity in patients with proven or suspected Crohn's disease.Superior mesenteric artery flow was measured prospectively in 31 patients with known or suspected small-bowel disease. Sixteen patients were known to suffer from Crohn's disease and were suspected of having active disease. Fifteen patients had abdominal complaints without a specific diagnosis. Enteroclysis was used as the standard of reference to detect Crohn's disease, to define the location of small-bowel Crohn's disease, and to assess disease activity by demonstrating cobblestoning. Disease activity was further substantiated by clinical signs, laboratory values, and clinical follow-up.Ten patients with active disease on enteroclysis made up group 1. Group 2 comprised nine patients known to have Crohn's disease but without active disease (inactive small-bowel disease). The remaining 12 patients made up group 3. In group 1, the flow volume values were significantly higher than those in group 2 and group 3: 738 +/- 411 (mean +/- SD) versus 364 +/- 101 and 300 +/- 91, respectively (p0.05).Whereas the initial diagnosis of small-bowel involvement in Crohn's disease may rely on enteroclysis, Doppler measurements of superior mesenteric artery flow are useful to monitor the activity of Crohn's disease.

The aim was to study the reproducibility of magnetic resonance velocity mapping, when measuring portal vein and superior mesenteric artery blood flow, under fasting and post-prandial conditions. Magnetic resonance flow measurements for the portal vein were compared with echo-Doppler measurements in the right portal vein.Eight healthy volunteers were studied on two occasions, separated by 1 week. Blood flow in the portal vein and superior mesenteric artery was measured repeatedly under basal fasting conditions. On one occasion measurements were also made after a meal. Every magnetic resonance measurement was followed by an echo-Doppler measurement in the right portal vein. Correlations between flow values were calculated using Pearson's r. Variability components were assessed using ANOVA.Intra-individual variability was approximately 7% for portal vein flow measurements using magnetic resonance velocity mapping. This variability did not increase after 1 h, 1 week and after a meal. Values of flow measured in the portal vein and superior mesenteric artery using magnetic resonance velocity mapping correlated well (r = 0.80, p0.001). Fasting portal flow as measured with magnetic resonance velocity mapping was 1.2 l/min (range 0.96-1.6 l/min). Variability in echo-Doppler measurements was comparable to the variability of magnetic resonance velocity mapping, and flow measurements obtained with the two techniques correlated well (r = 0.74; p0.001).Magnetic resonance velocity mapping accurately measures blood flow in the portal vein with low variability and should be preferred when absolute flow values are necessary. Echo-Doppler measurement of the right portal vein has a low variability and can be used to study changes in flow.

To compare digital subtraction angiography with three-dimensional phase-contrast magnetic resonance (MR) angiography in detection of significant renal artery stenosis.Sixteen patients underwent digital subtraction angiography and systolically gated three-dimensional phase-contrast MR angiography within 1 week. Scoring of stenosis on MR angiograms was based on presence and length of a flow void and quality of flow signal intensity in the distal part of the artery. Intraarterial pressure measurement was the reference standard for hemodynamically significant renal artery stenosis.MR angiography depicted two of five patent accessory arteries. Comparison of digital subtraction angiography and MR angiography with intraarterial pressure measurements was possible in 25 main renal arteries. In 13 arteries, a pressure gradient of more than 15 mm Hg was found. Digital subtraction angiography depicted 10 of these stenoses (sensitivity, 77%; specificity, 92%). A flow void was present at MR angiography in eight stenoses (sensitivity, 62%; specificity, 83%). In 12 of the stenosed vessels, distal flow signal intensity was impaired at MR angiography (sensitivity, 92%; specificity, 75%). There was no difference between the two modalities (P.05) in grading hemodynamic significance of renal artery stenosis.Systolically gated MR angiography and digital subtraction angiography are equally effective in depicting hemodynamically significant stenoses in the main renal arteries. MR angiography, however, is not adequate in depiction of accessory renal arteries.

Background Historical guidelines suggest limited efficacy for nonfusion treatment of chronic atlanto-axial rotatory subluxation/fixation (AARF). Surgical fusion has potential side effects; therefore, it is important to understand the role for nonfusion treatment of chronic AARF. This case series examines the success rate of nonfusion treatment. Methods A key word search was used to identify all patients with AARF with delayed presentation of ≥ 4 weeks. Fifteen patients met study inclusion criteria and had adequate clinical information for review. Data collected included age, sex, delay in presentation, mechanism of injury, severity of subluxation (Fielding classification), treatment, follow-up, and clinical information at latest follow-up. Results There were 11 girls and 3 boys with an average age of 7.2 years (range, 1.5 to 12 years). Initial treatment of 3 patients included fusion. Eleven patients were initially treated without fusion. Eight of these 11 patients were successfully reduced with either halter traction, halo gravity traction, and noninvasive halo or halo vest, and reduction was maintained without fusion (73%) at 10.3 years follow-up. Three patients (27%) experienced recurrence of AARF at an average time of 2 weeks (range, 0 to 4 wk) and were treated with fusion. Average delay in presentation for all patients was 18 weeks (range, 4 to 92 wk), whereas it was 6 weeks and 9.3 weeks in those successfully treated without fusion and in those who failed nonfusion treatment, respectively. Age, delay in presentation, and underlying diagnosis were similar for fusion and nonfusion groups. Conclusions Although AARF may recur after a trial of reduction and nonfusion treatment, pediatric patients with delayed presentation (>1 month) of AARF may be treated with an initial trial of nonfusion treatment. Parents should be counseled about the risk of recurrence and possible need for ultimate fusion. Level of evidence Level III, therapeutic retrospective comparative study.

to investigate whether morphologic characteristics determined by magnetic resonance imaging (MRI) can discriminate between bulky cervical tumours with a favourable or worse prognosis.MRI examinations were performed in 24 patients with cervical cancer Stageor= 1B2. The ratio between tumour width and length (barrel index: BI) and the presence of intrauterine fluid retention were related to survival in a multivariate regression analysis.BI and intracavital fluid were predictors of survival, independent from tumour diameter and other known important factors for survival. A cut-off value of 1.40 for the BI proved to be the best prognostic factor with respect to recurrence and death: the hazard ratios of BI1.40 as compared to BIor= 1.40 were 18.9 (95% CI 2.8 to 125.6) for recurrent disease and 16.4 (95% CI 2.9 to 93.9) for death by cervical cancer. The hazard ratios of intracavital fluid retention were 73.6 (95% CI 5.3 to 1,016.4) and 48.1 (95% CI 4.7 to 491.6) for recurrence and death, respectively.The morphologic characteristic BI and the presence or absence of intracavital fluid as determined by MRI might have predictive value for survival in patients with bulky cervical tumours.

Our goal was to assess the value of MRA for detecting stenoses in the celiac (CA) and superior mesenteric (SMA) arteries in patients suspected of having chronic mesenteric ischemia, using an optimized systolically gated 3D phase contrast technique. In an initial study in 24 patients who underwent conventional angiography of the abdominal vessels for different clinical indications, a 3D phase contrast MRA technique (3D-PCA) was evaluated and optimized to image the CAs and SMAs. Subsequently, a prospective study was performed to assess the value of systolically gated 3D-PCA in evaluation of the mesenteric arteries in 10 patients with signs and symptoms of chronic mesenteric ischemia. Intraarterial digital subtraction angiography and surgical findings were used as the reference standard. In the initial study, systolic gating appeared to be essential in imaging the SMA on 3D-PCA. In 10 patients suspected of mesenteric ischemia, systolically gated 3D-PCA identified significant proximal disease in the two mesenteric vessels in 4 patients. These patients underwent successful reconstruction of their stenotic vessels. Cardiac-gated MRA may become a useful tool in selection of patients suspected of having mesenteric ischemia who may benefit from surgery. 16 refs., 6 figs., 4 tabs.

A new multiple electrode probe, the Multiple Array Probe Leiden (MAPLe), has been developed for biofeedback registration of the individual pelvic floor musculature (PFM). The aim was to determine the reliability and differentiation of electromyography (EMG) signals measured with the MAPLe in healthy volunteers.Two hundred twenty nine healthy volunteers not seeking treatment or using medication for symptoms of prolapse, lower urinary tract, bowel, pain, and/or sexual function related to pelvic floor dysfunction were qualified to participate. Subjects were asked to perform five tasks: rest, maximum voluntary contractions, endurance, cough, and valsalva. Mean EMG values per electrode were registered. Test-retest reliability was assessed using linear mixed model with random subject effects. One-way ANOVA tests were performed to detect differences between groups.Magnetic resonance imaging (MRI) showed that each of the electrodes could be related nearest to the individual muscles. For test-retest, the intraclass correlation ranged from 0.53 to 0.91. The MAPLe showed significant differences in average EMG values between men and women, and between nulliparous and parous, pre- and prostmenpausal women. Significant differences were seen between the left and right sides of the pelvic floor. In addition, the activity nearest to the individual pelvic floor muscles (external anal sphincter (EAS), puborectalis muscle, bulbospongiosus, ischiocavernosus and the pubococcygeus muscle) could be determined.The MAPLe is a reliable instrument measuring the EMG signals of the different sides and levels nearest to the pelvic floor musculature and is capable to differentiate between men and women, nulliparous, parous, pre- and postmenopausal. The findings of this study have implications for the diagnosis and treatment of pelvic floor dysfunction in the future.

Background: It is recommended that BRCA1/2 mutation carriers undergo breast cancer screening using MRI because of their very high cancer risk and the high sensitivity of MRI in detecting invasive cancers. Clinical observations suggest important differences in the natural history between breast cancers due to mutations in BRCA1 and BRCA2, potentially requiring different screening guidelines. Methods: Three studies of mutation carriers using annual MRI and mammography were analyzed. Separate natural history models for BRCA1 and BRCA2 were calibrated to the results of these studies and used to predict the impact of various screening protocols on detection characteristics and mortality. Results: BRCA1/2 mutation carriers (N = 1,275) participated in the studies and 124 cancers (99 invasive) were diagnosed. Cancers detected in BRCA2 mutation carriers were smaller [80% ductal carcinoma in situ (DCIS) or ≤10 mm vs. 49% for BRCA1, P < 0.001]. Below the age of 40, one (invasive) cancer of the 25 screen-detected cancers in BRCA1 mutation carriers was detected by mammography alone, compared with seven (three invasive) of 11 screen-detected cancers in BRCA2 (P < 0.0001). In the model, the preclinical period during which cancer is screen-detectable was 1 to 4 years for BRCA1 and 2 to 7 years for BRCA2. The model predicted breast cancer mortality reductions of 42% to 47% for mammography, 48% to 61% for MRI, and 50% to 62% for combined screening. Conclusions: Our studies suggest substantial mortality benefits in using MRI to screen BRCA1/2 mutation carriers aged 25 to 60 years but show important clinical differences in natural history. Impact: BRCA1 and BRCA2 mutation carriers may benefit from different screening protocols, for example, below the age of 40. Cancer Epidemiol Biomarkers Prev; 21(9); 1458–68. ©2012 AACR.

Background & Aims Surveillance of high-risk groups for pancreatic cancer might increase early detection and treatment outcomes. Individuals with germline mutations in p16-Leiden have a lifetime risk of 15% to 20% of developing pancreatic cancer. We assessed the feasibility of detecting pancreatic cancer at an early stage and investigated the outcomes of patients with neoplastic lesions. Methods Individuals with germline mutations in p16-Leiden (N = 79; 31 male; mean age, 56 years; range, 39–72 years) were offered annual surveillance by magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP). Those found to have neoplastic lesions were offered options for surgery or intensive follow-up. Individuals found to have possible neoplastic lesions were examined again by MRI/MRCP within 2 to 4 months. Results After a median follow-up period of 4 years (range, 0–10 years), pancreatic cancer was diagnosed in 7 patients (9%). The mean age at diagnosis was 59 years (range, 49–72 years). Three of the tumors were present at the first examination, and 4 were detected after a negative result in the initial examination. All 7 patients had a resectable lesion; 5 underwent surgery, 3 had an R0 resection, and 2 had lymph node metastases. Possible precursor lesions (ie, duct ectasias, based on MRCP) were found in 9 individuals (11%). Conclusions MRI/MRCP detects small, solid pancreatic tumors and small duct ectasias. Although surveillance increases the rate of resectability, carriers of a p16-Leiden mutation develop agressive tumors.

Purpose: To prospectively compare the image quality and diagnostic performance achieved with doses of gadobenate dimeglumine and gadopentetate dimeglumine of 0.1 mmol per kilogram of body weight in patients undergoing contrast material-enhanced magnetic resonance (MR) angiography of the pelvis, thigh, and lower-leg (excluding foot) for suspected or known peripheral arterial occlusive disease. Materials and Methods: Institutional review board approval was granted from each center and informed written consent was obtained from all patients. Between November 2006 and January 2008, 96 patients (62 men, 34 women; mean age, 63.7 years +/- 10.4 [standard deviation]; range, 39-86 years) underwent two identical examinations at 1.5 T by using three-dimensional spoiled gradient-echo sequences and randomized 0.1-mmol/kg doses of each agent. Images were evaluated on-site for technical adequacy and quality of vessel visualization and offsite by three independent blinded readers for anatomic delineation and detection/exclusion of pathologic features. Comparative diagnostic performance was determined in 31 patients who underwent digital subtraction angiography. Data were analyzed by using the Wilcoxon signed-rank, McNemar, and Wald tests. Interreader agreement was determined by using generalized k statistics. Differences in quantitative contrast enhancement were assessed and a safety evaluation was performed. Results: Ninety-two patients received both agents. Significantly better performance (P < .0001; all evaluations) with gadobenate dimeglumine was noted on-site for technical adequacy and vessel visualization quality and offsite for anatomic delineation and detection/exclusion of pathologic features. Contrast enhancement (P < .0001) and detection of clinically relevant disease (P < .0028) were significantly improved with gadobenate dimeglumine. Interreader agreement for stenosis detection and grading was good to excellent (k = 0.749 and 0.805, respectively). Mild adverse events were reported for four (six events) and five (eight events) patients after gadobenate dimeglumine and gadopentetate dimeglumine, respectively. Conclusion: Higher- quality vessel visualization, greater contrast enhancement, fewer technical failures, and improved diagnostic performance are obtained with gadobenate dimeglumine, relative to gadopentetate dimeglumine, when compared intraindividually at 0.1-mmol/kg doses in patients undergoing contrast-enhanced MR angiography for suspected peripheral arterial occlusive disease. (c) RSNA, 2010

International audience; In order to assess the characteristics of malignant breast lesions those were not detected during screening by MR imaging. In the Dutch MRI screening study (MRISC), a non-randomized prospective multicenter study, women with high familial risk or a genetic predisposition for breast cancer were screened once a year by mammography and MRI and every 6 months with a clinical breast examination (CBE). The false-negative MR examinations were subject of this study and were retrospectively reviewed by two experienced radiologists. From November 1999 until March 2006, 2,157 women were eligible for study analyses. Ninety-seven malignant breast tumors were detected, including 19 DCIS (20%). In 22 patients with a malignant lesion, the MRI was assessed as BI-RADS 1 or 2. One patient was excluded because the examinations were not available for review. Forty-three percent (9/21) of the false-negative MR cases concerned pure ductal carcinoma in situ (DCIS) or DCIS with invasive foci, in eight of them no enhancement was seen at the review. In six patients the features of malignancy were missed or misinterpreted. Small lesion size ( = 3), extensive diffuse contrast enhancement of the breast parenchyma ( = 2), and a technically inadequate examination ( = 1) were other causes of the missed diagnosis. A major part of the false-negative MR diagnoses concerned non-enhancing DCIS, underlining the necessity of screening not only with MRI but also with mammography. Improvement of MRI scanning protocols may increase the detection rate of DCIS. The missed and misinterpreted cases are reflecting the learning curve of a multicenter study.

Fragestellung: Fur eine adaquate Beratung zur weiteren Familienplanung sind valide Daten zur Abschatzung des Wiederholungsrisikos nach einer hypertensiven Schwangerschaftskomplikation wie einer Praeklampsie unerlasslich. Methodik: Zur Verbesserung der Beratungsgrundlagen wurden 169 Folgeschwangerschaften von 169 Kaukasierinnen mit einer Praeklampsie in der Index-Schwangerschaft analysiert. Eine schwere Praeklampsie wurde bei einem Blutdruck ³ 160/110 mmHg nach der 20ten Schwangerschaftswoche und einer Proteinurie ³ 5g/L im 24h Urin oder ³ 3+ im U-Stix diagnostiziert. Ergebnisse: Von 169 Folgeschwangerschaften lag bei 41.4% ein normaler Blutdruck vor. Die Wiederholungsrate betrug 4.7% fur ein HELLP Syndrom, 28.4% fur eine Praeklampsie, und 23.1% fur eine Gestationshypertonie. Vier (2.4%) Frauen entwickelten nach der Index-Schwangerschaft eine chronische Hypertonie. Von 158 Frauen, welche sich hinsichtlich des Schweregrades der Praeklampsie eindeutig zuordnen liessen, zeigten 35 (22%) eine schwere Praeklampsie. Bei 94.3% der Frauen mit milder und 60% der Frauen mit schwerer Praeklampsie wurde in der Folgeschwangerschaft erneut eine hypertensive Komplikation diagnostiziert (p

Fragestellung: Hypertensive Schwangerschaftserkrankungen (HES) sind eine grosse Herausforderung fur Betroffene und das behandelnde medizinische Team. Ziel der vorliegenden Studie war die Erfahrungen von Frauen nach der Diagnose einer HES mit verschiedenen Belastungsfaktoren zu untersuchen. Methodik: Ein fur diese Fragestellung entwickeltes Fragebogeninventar wurde von 738 Frauen mit mindestens einer HES ausgefullt. Die statistische Auswertung erfolgte mittels Student-t, Fisher's exact und Chi Quadrat Test. Ergebnisse: Die drei Hauptbelastungsfaktoren waren die Unsicherheit in Bezug auf die Gesundheit des Kindes (307/41.6%), die Dauer des Krankenhausaufenthaltes (97/57%) und eine Entbindung per Sectio caesarea (226/39%). Die meisten Stressoren variierten mit dem Schwangerschaftsalter bei Entbindung. Schlussfolgerung: Die Diagnose einer HES fuhrt zu ausgepragtem Stress in der Schwangerschaft. Neben den Belastungsfaktoren bei anderen geburtshilflichen Komplikationen mussen sich Frauen bei einer HES sowohl mit der plotzlichen Veranderung des kindlichen Gesundheitszustandes wie auch mit ihrer eigenen teilweise lebensbedrohlichen Situation auseinandersetzen. Da Stress eine ungunstige Wirkung auf den Krankheitsverlauf haben kann, sollten diese Aspekte in die geburtshilfliche Betreuung integriert werden.

Fragestellung: Obwohl die Frage nach dem Wiederholungsrisiko eines HELLP-Syndroms einen zentralen Punkt fur die Entscheidung uber weitere Wunschschwangerschaften darstellt, sind die wissenschaftlich gesicherten Daten zu diesem Zusammenhang bisher sparlich. Methodik: Um eine Aussage zum Wiederholungsrisiko hypertensiver Schwangerschaftskomplikationen nach HELLP-Syndrom treffen zu konnen, wurden die Folgeschwanger-schaften von 148 Kaukasierinnen mit der Diagnose eines HELLP Syndrom in der Index-Schwangerschaft analysiert. Neben des Gesamtrisikos wurden der Schweregrad des HELLP Syndroms als Einflussfaktor in Bezug auf das Wiederholungsrisiko evaluiert. Ergebnisse: Von 148 Schwangerschaften nach einem HELLP Syndrom in der Index-Schwangerschaft wurde bei 56.1% der Frauen eine normotensive Schwangerschaft diagnostiziert. Das Wiederholungsrisiko betrug 12.8% fur ein HELLP Syndrom, 16.2% fur eine Praeklampsie, und 14.2% fur eine Gestationshypertonie. Wurde das HELLP Syndrom vor der 32ten Schwangerschaftswoche diagnostiziert so bestand ein erhohtes Risiko fur eine erneute hypertensive Schwangerschaftskomplikation. Schlussfolgerung: Fur Frauen mit der Diagnose eines HELLP Syndroms besteht ein deutlich erhohtes Risiko auch in der Folgeschwangerschaft an einem HELLP Syndrom, einer Praeklampsie oder einer Gestationshypertonie zu erkranken. Derzeit stehen jedoch weder klinische noch laborchemische Parameter zur Verfugung, welche eine individuelle Abschatzung des Risikos ermoglichen.

To prospectively determine diagnostic performance and safety of contrast material-enhanced (CE) magnetic resonance (MR) angiography with 0.1 mmol per kilogram of body weight gadobenate dimeglumine for depiction of significant steno-occlusive disease (or =51% stenosis) of renal arteries, with digital subtraction angiography (DSA) as reference standard.This multicenter study was approved by local institutional review boards; all patients provided written informed consent. Patient enrollment and examination at centers in the United States complied with HIPAA. Two hundred ninety-three patients (154 men, 139 women; mean age, 61.0 years) with severe hypertension (82.2%), progressive renal failure (11.3%), and suspected renal artery stenosis (6.5%) underwent CE MR angiography with three-dimensional spoiled gradient-echo sequences after administration of 0.1 mmol/kg gadobenate dimeglumine at 2 mL/sec. Anteroposterior and oblique DSA was performed in 268 (91.5%) patients. Three independent blinded reviewers evaluated CE MR angiographic images. Sensitivity, specificity, and accuracy of CE MR angiography for detection of significant steno-occlusive disease (or =51% vessel lumen narrowing) were determined at segment (main renal artery) and patient levels. Positive and negative predictive values and positive and negative likelihood ratios were determined. Interobserver agreement was analyzed with generalized kappa statistics. A safety evaluation (clinical examination, electrocardiogram, blood and urine analysis, monitoring for adverse events) was performed.Of 268 patients, 178 who were evaluated with MR angiography and DSA had significant steno-occlusive disease of renal arteries at DSA. Sensitivity, specificity, and accuracy of CE MR angiography for detection of 51% or greater stenosis or occlusion were 60.1%-84.1%, 89.4%-94.7%, and 80.4%-86.9%, respectively, at segment level. Similar values were obtained for predictive values and for patient-level analyses. Few CE MR angiographic examinations (1.9%-2.8%) were technically inadequate. Interobserver agreement for detection of significant steno-occlusive disease was good (79.9% agreement; kappa = 0.69). No safety concerns were noted.CE MR angiography performed with 0.1 mmol/kg gadobenate dimeglumine, compared with DSA, is safe and provides good sensitivity, specificity, and accuracy for detection of significant renal artery steno-occlusive disease.

SummaryAntifibrin monoclonal antibody Y22, of IgG1-subclass, has its epitope in the D-domain of fibrin. In a thrombin time assay, Y22 and its F(ab)2 fragments interfere with clotting of citrated plasma. Transmission and scanning electronmicroscopic studies show that clotting of citrated blood or plasma in the presence of Y22 results in formation of thin, short fibrin fibres. The (smaller) Fab fragments of Y22 did not have an anti-clotting effect. This suggests that the anticoagulant effect of Y22 is due to steric hindrance of the association of fibrin monomers. A control antibody and its F(ab)2 and Fab fragments have no effect on fibrin formation.In a parabolic rate assay, Y22 Fab fragments interfered strongly with the fibrin-induced enhancement of the t-PA-catalyzed plasminogen activation, whereas intact Y22 and a control antibody did not. In contrast with their effects on the fibrin assembly, the effects of Y22, Y22-F(ab)2 and Y22-Fab on the capacity of fibrin to act as a rate-enhancer in the plasminogen activation by t-PA appears to decrease with the size of the immunoreactive entity. As is discussed, this may be due to the differential accessibility of sites involved in stimulation and polymerization which are located in the fibrin D-domain.

The 'Arbeitsgemeinschaft Gestose-Frauen e.V.' was founded in 1984 with a couple of sufferers and has advised more than 24,000 women so far. In addition to the care by the midwife and gynaecologist, this self-help organization offers the possibility to exchange experiences with other sufferers, but also to receive medical and psychological counselling.

In this paper we introduce SocialBrowsing, a Firefox extension that adds social context to the web browsing experience. The extension is paired with services provided by social networking websites, analyzes the page's contents, and adds tooltips and highlighting to indicate when there is relevant social information. We present an overview of the tool and implementation, and outline future steps for analysis.

Background. Nonanastomotic biliary strictures (NAS) remain a frequent complication after orthotopic liver transplantation (OLT). The aim of this study was to evaluate whether magnetic resonance cholangiopancreatography (MRCP) could be used to detect NAS and to grade the severity of biliary strictures. Methods. In total, 58 patients after OLT from 2 Dutch transplantation centers in whom endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography and MRCP were performed within less than 6 months apart were included in the study. Of these patients, 41 had NAS and 17 were without NAS based on endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography and follow-up. Four radiologists—2 from each center—used an adapted validated classification—termed “Leiden Biliary Stricture Classification” “(LBSC)—to evaluate the MRCP examinations independently. In this classification, NAS severity is assessed in 4 hepatobiliary regions. Interobserver agreement of the severity score for each region was calculated with the κ statistics. Results. Optimal cutoff value of the LBSC to detect the presence of NAS with MRCP was calculated at 3 points or greater for all readers. Applying this cutoff sensitivity for each reader was greater than 90%, with a specificity of 50% to 82%, positive predictive value of 86% to 91%, and negative predictive value of 80% to 100%. The MRCP performance was better in evaluation of the intrahepatic than of the extrahepatic bile ducts. The additional value of MRCP for grading severity of NAS was limited. Conclusions. The MRCP with the LBSC is a reliable tool to detect or exclude NAS after OLT. Currently, MRCP cannot be used to reliably grade the severity of these strictures.

OBJECTIVE: The purpose of this study was to evaluate the role of contrast-enhanced dynamic MRI in predicting the disease activity of Crohn's disease. MATERIALS AND METHODS: Forty-eight patients in two hospitals who had clinically suspected exacerbation of Crohn's disease were included in this study. In three levels of thickened small-bowel wall, axial dynamic T1-weighted sequences were performed every 4-6 sec for a total duration of 2-3 min after contrast administration; static T1-weighted turbo spin-echo sequences were acquired both before and after contrast administration. The slope of enhancement, enhancement ratio, time to enhancement, enhancement time, and thickness of the small-bowel wall were determined. These MRI results were compared with overall clinical grade, Crohn's disease activity index (CDAI), and Van Hees activity index. Clinical grade was based on clinical information, physical findings, laboratory studies, endoscopy, surgery, and other imaging studies. Spearman's correlation coefficient and p values were determined per hospital. Fisher's z-transformation was applied before pooling the correlation coefficients from both hospitals. RESULTS: The enhancement ratio based on the static series showed significant correlation with the clinical grade (r = 0.29, p = 0.045), CDAI (r =0.31, p = 0.033), and Van Hees activity index (r = 0.36, p = 0.016). The enhancement ratio based on the dynamic series correlated significantly with the CDAI (r = 0.38, p = 0.016). Wall thickness correlated significantly with clinical grade (r = 0.47, p = 0.003) and Van Hees activity index (r = 0.41, p = 0.007). CONCLUSION: These data suggest that the enhancement ratio of bowel wall after IV administration of gadodiamide and bowel wall thickness are weak to moderate indicators of the severity of Crohn's disease

As a first generation model for the reactive reduced active-site form of bacterial nitric oxide reductase, a heme/non-heme diiron(II) complex [(6L)Fe(II)...Fe(II)-(Cl)]+ (2) {where 6L = partially fluorinated tetraphenylporphyrin with a tethered tetradentate TMPA chelate; TMPA = tris(2-pyridyl)amine} was generated by reduction of the corresponding mu-oxo diferric compound [(6L)Fe(III)-O-Fe(III)-Cl]+ (1). Coordination chemistry models for reactions of reduced NOR with O2, CO, and NO were also developed. With O2 and CO, adducts are formed, [(6L)Fe(III)(O2-))(thf)...Fe(II)-Cl]B(C6F5)4 (2a x O2) {lambda(max) 418 (Soret), 536 nm; nu(O-O) = 1176 cm(-1), nu(Fe-O) = 574 cm(-1) and [(6L)Fe(II)(CO)(thf)Fe(II)-Cl]B(C6F5)4 (2a x CO) {nu(CO) 1969 cm(-1)}, respectively. Reaction of purified nitric oxide with 2 leads to the dinitrosyl complex [(6L)Fe(NO)Fe(NO)-Cl]B(C6F5)4 (2a x (NO)2) with nu(NO) absorptions at 1798 cm(-1) (non-heme Fe-NO) and 1689 cm(-1) (heme-NO).

Single wavelength excitation (lambdaex = 355 or 532 nm) of low-temperature stabilized (198 K) synthetic heme-dioxygen and heme-dioxygen/M complexes, where M = copper or iron in a non-heme environment, results in the dissociation of dioxygen as indicated by the generation of the ferrous heme (Soret band, 427 nm) and the bleaching of the ferric-superoxide (FeIII(O2-)) 410-nm Soret band in the transient absorption difference spectrum. Dioxygen rebinds to the four heme complexes studied with comparable rate constants ( approximately 6-9 x 105 M-1 s-1). However, the quantum yield for complete dissociation of O2 from our simplest heme-O2 complex (F8)FeIII(O2-) (phi = 0.60) is higher than the other complexes measured (phi = approximately 0.2-0.3) as well as that for oxy-myoglobin (phi = 0.3).