First-pass myocardial perfusion MR imaging with interleaved notched saturation: feasibility study.

The authors evaluated a magnetization preparation scheme with a "notched" section profile for T1-weighted first-pass myocardial perfusion magnetic resonance (MR) imaging at 1.5 T. The pulse sequence consisted of a preparation sequence followed by an interleaved gradient-echo echo-planar sequence. Image contrast was evaluated in a feasibility study in 12 adult patients. The notched saturation pulse allowed long magnetization recovery times without sacrificing section coverage. Image contrast between normal and ischemic myocardium was excellent.

Two-dimensional multishot echo-planar coronary MR angiography.

This work presents a two-dimensional (2D) multishot echo-planar imaging (EPI) technique for magnetic resonance angiography (MRA) of individual coronary arteries in a 17-heartbeat breath-hold. Conventional 2D and 3D segmented gradient-echo (GRE) coronary MRA requires repetitive excitation of the same slice or slab within each cardiac cycle, which can result in reduced blood signal and in motion artifacts. Two-dimensional multishot EPI can address these limitations by eliminating multiple excitations per cardiac cycle, using large flip-angle excitations, markedly reducing the data acquisition window, and performing oblique multislice 2D imaging. The goal of this study was to assess the feasibility of breath-hold 2D multishot EPI for multislice coronary MRA and to demonstrate its reliability by consistently acquiring high-quality images of the coronary arteries in a series of 16 volunteers.

An orthogonal correlation algorithm for ghost reduction in MRI.

Ghosting in MRI due to modulation of k-space data can be caused by motion of the subject or characteristics of the sequence. A general solution for 2DFT MRI that reduces ghosting without causal modeling is presented. Separate image data sets are acquired in which the phase and frequency directions are swapped. In these two data sets, the image signal is correlated, whereas the ghost signals are not. By taking a correlation of these two data sets, an image with greatly reduced ghosting is obtained. The reduction is shown to depend both on the correct signal intensity of the image, as well as the ghost intensity in the ghosted region. The reduction approaches 100% in regions of low image signal, and is more moderate in regions of higher image signal. The process was applied to conventional spin-echo, fast-spin-echo, and gradient echo imaging of volunteers and a phantom. Results of a reader study of the volunteer images reflected a significant overall reduction of ghosting artifacts in all volunteer experiments.

Gradient moment smoothing: a new flow compensation technique for multi-shot echo-planar imaging.

This work identifies an additional source of phase error across ky in multi-shot echo-planar imaging resulting from flow or motion along the phase-encoding direction. A velocity-independent flow compensation technique, gradient moment smoothing, is presented that corrects this error by forcing the phase to have smooth quadratic behavior. The correction is implemented, without compromising scan time, by changing the first moment of a bipolar prephaser pulse on a shot-by-shot basis. In phantom and in vivo experiments, gradient moment smoothing effectively eliminates ghosting and signal loss due to phase-encoding flow. When used in conjunction with a "flyback" echo-planar readout, which compensates for flow in the frequency-encoding direction, gradient moment smoothing renders multi-shot echo-planar imaging relatively insensitive to in-plane flow. This can make multi-shot echo-planar imaging a viable technique for accurately imaging in-plane flow and may desensitize it to the otherwise serious problem of in-plane motion.

Zonal biochemical and morphological characteristics in BPH.

OBJECTIVE: To compare androgen, oestrogen, progesterone and epidermal growth factor receptor concentrations in the transition zone and peripheral zone of the prostate in benign prostatic hyperplasia (BPH), and to relate these findings to epithelial and stromal composition. PATIENTS AND METHODS: Tissue from both the transition and peripheral zone of the prostate was obtained from 26 patients undergoing transurethral prostatectomy for benign prostatic obstruction and used for both receptor binding studies and morphometric analysis. Androgen receptor (AR), oestrogen receptor (ER), progesterone receptor (PR) and epidermal growth factor receptor (EGFR) concentrations were assayed by saturation binding with a competitive inhibitor. The epithelial, stromal and luminal composition of the tissue was determined using a Zeiss AxioHOME microscope workstation. RESULTS: The epithelial content was significantly greater in the transition zone than in the peripheral zone. No overall zonal difference in AR concentration was detected; however, when values were expressed relative to the epithelial component, the AR content was significantly higher in the peripheral zone. Conversely, overall EGFR concentrations were significantly greater in the transition zone, although not when expressed per unit epithelium. Higher concentrations of oestrogen receptor were measured in the transition zone per unit stroma. No zonal difference in PR was detected. However, there was a significant correlation between AR and PR in the peripheral zone and between EGFR and AR in the transition zone. CONCLUSION: These data demonstrate that receptor concentrations should be related to tissue composition. Concentrations of AR were higher in the peripheral zone epithelium than in transition zone epithelium, suggesting greater androgen dependence. This may be important in determining its greater propensity for malignancy. Although EGFR concentrations were greater in the transition zone, there was no zonal difference after correction for the amount of epithelium. Finally, higher concentrations of ER were detected in the transition zone stroma which may reflect important zonal differences in regulating growth and provides further evidence of a role for oestrogens in BPH.

Dual-echo interleaved echo-planar imaging of the brain.

An interleaved echo-planar imaging (EPI) technique is described that provides images from 20 sections of the brain at two echo times (27 and 84 ms) in 1:05. Six echoes per image per repetition are collected in 24 repetitions of the pulse sequence. MR images of the brain obtained from five volunteers using the dual-echo EPI sequence, fast spin-echo (FSE), and conventional dual-echo spin-echo were evaluated qualitatively for diagnostic use and quantitatively for relative signal-to-noise ratio (SNR), contrast, and contrast-to-noise ratios (CNR).

New technical developments in magnetic resonance imaging of epilepsy.

Within the last several years a number of technical developments have been made in magnetic resonance imaging (MRI) that can potentially impact clinical and research MR imaging application in epilepsy. These include developments in instrumentation and in pulse sequences. Advances in instrumentation include higher capacity gradient systems and multiple receiver coils as directed to brain imaging. Advances in pulse sequence include use of fast or turbo-spin-echo techniques, variants of echo-planar imaging, and sequences such as fluid-attenuation inversion recovery (FLAIR) targeted to specific applications of brain imaging. The purpose of this paper is to review several of these developments.

Successful purging of murine plasmacytoma by mafosfamide (ASTA-Z).

Mafosfamide (ASTA-Z) is a chemotherapeutic agent currently in use for in vitro purging of tumor-bearing human BM cells prior to autologous bone marrow transplantation (ABMT). We tested the efficacy of ASTA-Z against mouse plasmacytoma cells MOPC-315 (MOPC), a model of human multiple myeloma. BALB/c mice were injected intraperitoneally with different doses of MOPC preincubated with ASTA-Z. All control mice receiving > or = 10(4) MOPC intraperitoneally (ip) died within 23 days. All recipients of ASTA-Z pretreated MOPC remained healthy for > 180 days. To simulate the clinical situation, BALB/c mice received lethal doses of 10(3) MOPC ip prior to ABMT. Subsequently, mice were treated with cyclophosphamide 200 mg/kg one day prior to syngeneic BMT with 10(7) BMC containing 10(6) MOPC; 90% of the mice receiving unpurged syngeneic BMC died within 45 days whereas all mice transplanted with ASTA-Z-treated BMC/MOPC mixtures remained disease-free for > 100 days. Our results suggest that a similar approach may be successful in patients with multiple myeloma and residual disease prior to cryopreservation of their BM for ABMT. Bone marrow purging with ASTA-Z is effective and under certain conditions could be critical for prevention of relapse following ABMT, provided that effective elimination of residual disease in the host can be achieved by the conditioning regimen prior to ABMT.

Epstein-Barr virus infection and bcl-2 proto-oncogene expression. Separate events in the pathogenesis of Hodgkin's disease?

The present study was undertaken to investigate whether Epstein-Barr virus-(EBV) encoded latent membrane protein (LMP) induces the expression of BCL-2 in Hodgkin and Reed-Sternberg (HRS) cells of Hodgkin's disease (HD) and thereby provide a possible mechanism for the role of EBV in the pathogenesis of this disease. Fifty-three cases of HD were studied for the presence of EBV using EBV-encoded RNA in situ hybridization and LMP immunohistochemistry. Immunostaining for BCL-2 on paraffin material was performed using microwave treatment of tissue sections before the application of the primary monoclonal antibody. EBV was located in HRS cells in 16 cases (30%). All cases that were EBV-encoded RNA in situ hybridization positive, also expressed LMP. BCL-2 expression in HRS cells was detected in 16 cases (30%), but only two of these were also EBV-positive. In both of these cases, only occasional HRS cells expressed BCL-2, in contrast to LMP, which was detected in nearly all such cells. BCL-2 staining was predominantly cytoplasmic with some membrane pattern. These results demonstrate that BCL-2 expression can be detected in HRS cells in routinely processed HD tissue and that whereas EBV does not induce the expression of BCL-2 in HD, BCL-2 may have a role in the pathogenesis of EBV-negative cases of HD.

Epstein-Barr virus in Hodgkin disease. Relation to age and subtype.

BACKGROUND: Epstein-Barr virus (EBV) has been associated with Hodgkin disease (HD), but its relationship to the age of the patients and the histologic subtype is not well defined. The possibility that other lymphotropic herpesviruses, such as cytomegalovirus (CMV) and human herpesvirus type 6 (HHV-6) could be involved in the pathogenesis of HD is also unclear. METHODS: Paraffin-embedded material from 77 cases of HD was studied. This consisted of 24 specimens from children (mean age, 11.4 years), 36 from young adults (mean age, 28.8 years), and 17 from older adults (mean age, 53.8 years). EBV was detected in Hodgkin and Reed-Sternberg cells (HR-S) by a sensitive in situ hybridization technique based on the detection of Epstein-Barr-encoded RNA. Viral activity was subsequently demonstrated in HR-S cells by using monoclonal antibodies to EBV latent membrane protein. RESULTS: EBV was found in a total of 25 of 77 cases (32%). There was no significant difference in EBV positivity between the different age groups. However, the prevalence of EBV varied between different subtypes: 68% of mixed cellularity cases were found to be positive by contrast with 24% nodular sclerosis, 0% lymphocyte predominant, and 14% lymphocyte depleted. Analysis of the histologic reports of a further 783 cases of HD to determine the age distribution of the different subtypes revealed an absence of an older adult second peak in the age distribution curve. In situ hybridization for CMV and HHV-6 was negative in all cases. CONCLUSIONS: It was concluded that EBV is predominantly associated with mixed cellularity HD, and there is no correlation with the age of the patient.

Epstein-Barr virus in angioimmunoblastic T-cell lymphomas.

Epstein-Barr virus (EBV) has been proposed as a possible infective agent involved in the pathogenesis of angioimmunoblastic lymphadenopathy (AIL), a progressive and often fatal lymphoproliferative disorder. We have studied 19 cases of AIL-like lymphomas for the presence of EBV using a sensitive in situ hybridization technique based on the detection of Epstein-Barr encoded RNAs with digoxigenin-labelled oligonucleotide probes. EBV was found in 11 cases; in seven of these EBV was detected in occasional cells. Immunocytochemical studies to investigate viral gene expression, revealed the presence of EBV-encoded latent membrane protein only in those cases which had appreciable numbers of positive cells by in situ hybridization. The intensity of staining varied from case to case and the overall proportion of cells staining for latent membrane protein in a given case was considerably less than that by in situ hybridization. In situ hybridization for cytomegalovirus and human herpes virus type-6 was negative in all cases. We discuss these findings in the light of the proposed role of EBV in the pathogenesis of AIL and conclude that the presence of EBV is a consequence of the disease rather than the cause.

Epstein-Barr virus in Reed-Sternberg-like cells in non-Hodgkin's lymphomas.

In the course of our study on Hodgkin's disease (HD), ten cases of non-Hodgkin's lymphomas (NHL) containing Hodgkin and Reed-Sternberg-like (HRS) cells were encountered. Many of these cases had initially been diagnosed as HD, but on careful review of the histology, with the aid of immunophenotyping studies, they were reclassified as NHL. The presence of Epstein-Barr virus (EBV) in these HRS-like cells was investigated using a combination of EBER in situ hybridization (ISH) and immunostaining for the detection of EBV-encoded latent membrane protein (LMP). HRS-like cells in four cases (two lymphoplasmacytoid lymphomas, one Richter's transformation of lymphoplasmacytoid lymphoma, and one immunoblastic lymphoma of T-cell type) were found to be EBV-positive. In two of these cases, a second biopsy taken up to 10 years later also contained EBV in the HRS-like cells. In three of the four cases, HRS-like cells expressed the activation antigen CD30, but the expression of B- or T-cell antigens was variable. All cases of T-cell-rich B-cell lymphomas were negative for EBV. In conclusion, EBV may play a role in the development of HRS-like cells in some cases of NHL. The relationship of HRS-like cells to HRS cells of HD is discussed.

Detection of Epstein-Barr virus in Reed-Sternberg cells of Hodgkin's disease arising in children.

Nonisotopic in situ hybridization has been used to investigate the role of Epstein-Barr virus (EBV) in the aetiology of pediatric Hodgkin's disease. Sections from 24 cases arising in children under the age of 15 years were hybridised with digoxigenin-labelled probes for both EBV and cytomegalovirus, and reactive sites were identified by a sensitive three-layer immunoperoxidase technique. EBV was identified in Reed-Sternberg and mononuclear Hodgkin's cells in five samples (21%). No samples were positive when the cytomegalovirus probe was employed. The specific identification of EBV in the malignant cells of Hodgkin's disease arising in children lends further support for a role of EBV in the aetiology of this disorder.

Predicting the outcome of radical radiotherapy for invasive bladder cancer.

The correlation between T stage, histological grade, the presence of squamous metaplasia, and nuclear morphometry scores and response to radiotherapy and survival was investigated in 60 patients with muscle invasive transitional cell carcinomas of the bladder. Patients with T2 tumours showed a complete response significantly more often than those with T3 lesions. Multivariate analysis showed that T stage and initial response to radiotherapy were very strong predictors of survival though they were not independent variables. Histological grade, the presence of squamous metaplasia, and nuclear morphometry scores were not found to have any predictive value.

Recurrent abdominal pain of gastro-intestinal origin.

A consecutive series of 71 children (mean age 8.6 years) with recurrent abdominal pain underwent endoscopic oesophageal, gastric and duodenal biopsy in order to determine whether the pain was of gastro-intestinal origin. Of these 71 children, 27 (38%) showed oesophagitis, 14 (20%) cardiac gastritis, 29 (41%) body gastritis, 38 (54%) antral gastritis, and 29 (41%) duodenitis. Thus, 66 of the 71 children studied had an inflammatory lesion explaining their complaints. One of the patients had a gastric ulcer. Helicobacter pylori colonisation was found in 5 of the children: One had H. pylori associated antral and body gastritis and 4 H. pylori associated antral gastritis only. Body gastritis without H. pylori was present in three of these four children. Our data do not support the widespread assumption that recurrent abdominal pain for which no medical cause can be found, is psychogenic; neither do they establish an association between H. pylori antral gastritis and recurrent abdominal pain. However, our data provide strong evidence that there is a gastro-intestinal origin of these patients' complaints.

Epstein Barr virus (EBV) encoded small RNAs: targets for detection by in situ hybridisation with oligonucleotide probes.

AIMS: To develop a rapid, sensitive, and specific non-isotopic in situ hybridisation (NISH) procedure for the detection of Epstein-Barr virus in formalin fixed, paraffin wax embedded tissues. METHODS: Two low molecular weight RNAs, designated EBER-1 and EBER-2 (Epstein-Barr encoded RNA), were used: cells latently infected with EBV secrete large amounts of EBERs. The method uses digoxigenin labelled anti-sense oligonucleotides, corresponding to sequences in EBER-1 and EBER-2. RESULTS: The use of these probes, in conjunction with high temperature microwave denaturation, ensured that the technique was considerably more sensitive than other in situ hybridisation techniques for detecting EBV. Furthermore, the hybridisation signal was morphologically distinct in that only the nucleus and not the nucleolus give a positive signal. No cross-hybridisation was observed with cells infected with other lymphotropic herpes viruses. CONCLUSION: The sensitivity, simplicity, and rapidity of this technique make it ideal for diagnostic use, and for studies investigating the role of this virus in neoplastic disease.

Presence of Epstein-Barr virus in Hodgkin's disease is not exclusive to Reed-Sternberg cells.

Thirty-three cases of Hodgkin's disease (HD) have been studied for the presence of Epstein-Barr virus (EBV) using a novel nonisotopic in situ hybridization procedure, based on the detection of Epstein-Barr encoded RNAs with oligonucleotide probes. An intense and morphologically distinct nuclear staining, sparing the nucleolus was seen in a total of 12 cases (36%). In six of these cases, the signal was located to the Hodgkin and Reed-Sternberg cells (HR-S); in the other six positive cases, the signal was observed only in the non-neoplastic small lymphocytes. These lymphocytes were few in number and immunocytochemistry results were consistent with a B-cell phenotype. The presence of EBV in those cases characterized by nuclear staining of small lymphocytes was confirmed by the polymerase chain reaction (PCR) analysis. The authors report the detection of EBV in small lymphocytes in HD by in situ hybridization and discuss the implications of these findings in relation to the proposed etiologic association between EBV and HD.

Persistence of Epstein-Barr virus in Reed-Sternberg cells throughout the course of Hodgkin's disease.

Non-isotopic in situ hybridization employing digoxigenin-labelled DNA probes has been used to localize Epstein-Barr virus (EBV) in 55 cases of Hodgkin's disease (HD). The virus was found in Reed-Sternberg (RS) and mononuclear Hodgkin's cells in nine patients (16 per cent). Further samples taken at different times from three patients also showed the presence of EBV in the malignant cell population. Estimations of the number of EBV genomes present per cell suggested wide variations between different patients, but relatively constant amounts in different samples from the same patient. These findings are compatible with a stable infection of the neoplastic cells and support the notion that EBV may play a role in the development of HD in these patients. We also found evidence for the presence of EBV in a small percentage of non-neoplastic cells in 8 of the 55 samples. This suggests that isolation of EBV from HD tissue does not always signify a pathogenetic role for the virus. Furthermore, it is apparent that a high percentage of HD tissues do not contain demonstrable EBV, and the virus is therefore unlikely to be a causative agent for all cases of HD.