Three-dimensional magnetic resonance myocardial motion tracking from a single image plane.

Three-dimensional imaging for the quantification of myocardial motion is a key step in the evaluation of cardiac disease. A tagged magnetic resonance imaging method that automatically tracks myocardial displacement in three dimensions is presented. Unlike other techniques, this method tracks both in-plane and through-plane motion from a single image plane without affecting the duration of image acquisition. A small z-encoding gradient is subsequently added to the refocusing lobe of the slice-selection gradient pulse in a slice following CSPAMM acquisition. An opposite polarity z-encoding gradient is added to the orthogonal tag direction. The additional z-gradients encode the instantaneous through plane position of the slice. The vertical and horizontal tags are used to resolve in-plane motion, while the added z-gradients is used to resolve through-plane motion. Postprocessing automatically decodes the acquired data and tracks the three-dimensional displacement of every material point within the image plane for each cine frame. Experiments include both a phantom and in vivo human validation. These studies demonstrate that the simultaneous extraction of both in-plane and through-plane displacements and pathlines from tagged images is achievable. This capability should open up new avenues for the automatic quantification of cardiac motion and strain for scientific and clinical purposes.     

Small-animal PET of tumor angiogenesis using a (76)Br-labeled human recombinant antibody fragment to the ED-B domain of fibronectin.

The aim of this study was to image the extra domain B (ED-B) of fibronectin, an angiogenesis-related target, in solid tumors using small-animal PET. Toward this aim, an ED-B fibronectin-binding human antibody derivative (L19-SIP) was labeled with (76)Br via an enzymatic approach. Biodistribution and imaging studies were performed in human teratoma-bearing mice for up to 48 h after injection. METHODS: L19-SIP was labeled with (76)Br using bromoperoxidase/H(2)O(2). The stability of the labeled antibody was tested both in vitro and in vivo. Biodistribution and small-animal imaging studies (PET and CT) were performed in F9-bearing 129/sv mice (n = 3 or 4). RESULTS: The enzymatic radiobromination approach afforded the labeled antibody in high yield (>55%) under mild reaction conditions. (76)Br-L19-SIP stability in mouse serum proved to be similar to that of the (125)I-labeled analog (>80% of intact material at 48 h after injection). Fast and specific in vivo targeting was obtained in tumors and other organs expressing ED-B fibronectin (i.e., ovaries and uterus). However, slow renal clearance and persistent activity predominately in blood and stomach suggests partial (76)Br-L19-SIP debromination in vivo. This debromination was confirmed in a metabolism study in normal mice. The F9 tumors were clearly imaged by small-animal PET at each considered time point, starting at 5 h up to 48 h after injection. CONCLUSION: (76)Br-L19-SIP specifically accumulated at the target site, enabling detailed small-animal PET of tumor neovasculature. Therefore, targeting the angiogenesis-associated expression of ED-B fibronectin can be a valuable tool for tumor detection using molecular imaging with PET.     

Targeted stent use in clinical practice based on evidence from the Basel Stent Cost Effectiveness Trial (BASKET): reply

We thank Agostini Pierfranco and colleagues for their interestin our analysis of the     

Learning and memory: regional changes in N-methyl-D-aspartate receptors in the chick brain after imprinting.

An extensive series of experiments has implicated a restricted region of the chick forebrain in the learning process of imprinting. The region is the intermediate and medial part of the hyperstriatum ventrale (IMHV). Previous studies have shown that training is associated with an increase in the area of the postsynaptic density of axospinous synapses in the left but not the right IMHV. The postsynaptic density is a site of high receptor density, and at least some axospinous synapses are excitatory. We found that imprinting is associated with a 59% increase in N-methyl-D-aspartate-sensitive binding of the excitatory amino acid L-[3H]glutamic acid in the left IMHV. The increase is probably due to an increased number of binding sites. The profile of sensitivity of the sites to a series of amino-, phosphono-substituted carboxylic acids (2-amino-3-phosphonopropionate to 2-amino-8-phosphonooctanoate) is characteristic of N-methyl-D-aspartate-type receptors. There were no significant effects of training on binding in the right IMHV. The effect of training on left IMHV binding could not be attributed to light exposure, arousal, or motor activity per se but was a function of how much the chicks learned. The changes in the left IMHV could increase the effectiveness of synaptic transmission in a region crucial for information storage and so form a neural basis for recognition memory.     

Ewing's sarcoma of bone: Oncologic and functional results

This paper describes 29 patients with Ewing's sarcoma of bone treated between 1975 and 1990 at the University of Nijmegen Hospital, Nijmegen, The Netherlands. Osteomyelitis was the primary diagnosis in 24%. Treatment consisted of chemotherapy in combination with surgery and/or radiotherapy. Nine patients received radiotherapy only; five of them died of disease. Five patients underwent an intralesional excision; four of them died of disease. Twelve patients underwent a wide excision; there is no evidence of disease in any of them. Three patients underwent a radical disarticulation; all died of disease. The disease-free survival at 1.5 years was 66%. This figure at 5 years was 55%. After wide excision and reconstruction in tumors of expendable, femoral or radial bones good functional results were obtained in all cases. © 1995 Wiley-Liss, Inc.     

Determinants of the public's preference for social distance from people with schizophrenia.

OBJECTIVE: To examine the extent to which the public's desire for social distance from people with schizophrenia is influenced by beliefs about the disorder and stereotypes about those suffering from it. METHODS: In spring 2001, we carried out a representative survey of individuals of German nationality aged 18 years and over (n = 5025). Each subject was given a fully structured interview that began with the presentation of a vignette. RESULTS: Both labelling and beliefs about the disorder's causes and prognosis, as well as the perception that those suffering from it are unpredictable and dangerous, had an impact on the public's desire for social distance. However, the latter proved to be more important. As expected, respondents who identified the disorder depicted in the vignette as mental illness, those who blamed the individual for its development, and those who anticipated a poor prognosis expressed a stronger desire for social distance. Endorsing biological factors as a cause was also associated with increased social distance. CONCLUSIONS: Our findings have important implications for interventions aimed at reducing stigma and discrimination related to schizophrenia. Targeting the stereotype of unpredictability and dangerousness appears to be particularly important.     

Alterations in cholinergic and non-cholinergic neurotransmitter receptor densities in transgenic Tg2576 mouse brain with beta-amyloid plaque pathology.

Cholinergic deficits in Alzheimer's disease are accompanied by a number of alterations in other transmitter systems including glutamate, noradrenaline and serotonin, suggesting the involvement also of other neurotransmitter systems in the pathogenesis of the disease. To address the question whether beta-amyloid may contribute to these deficits, brain tissue from transgenic Tg2576 mice with Alzheimer plaque pathology at ages of 5 (still no significant plaque load) and 17 months (moderate to high cortical beta-amyloid plaque load) were examined for a number of cholinergic and non-cholinergic markers. Transgenic mice with no significant plaque load demonstrated reduced hemicholinium-3 (HCh-3) binding to choline uptake sites in anterior brain regions as compared to non-transgenic littermates, while in aged transgenic mice with high number of plaque deposits decreased HCh-3 binding levels were accompanied by increased vesicular acetylcholine transporter binding in selected cortical brain regions. In aged transgenic mice GABA(A), NMDA, AMPA, kainate, and beta-adrenergic as well 5-HT(1A)- and 5-HT(2A)-receptor binding levels were hardly affected, whereas alpha(1)- and alpha(2)-adrenoceptor binding was increased in selected cerebral cortical regions as compared to non-transgenic littermates. The development of changes in both cholinergic and non-cholinergic markers in transgenic Tg2576 mouse brain already before the onset of progressive plaque deposition provides in vivo evidence of a modulatory role of soluble beta-amyloid on cortical neurotransmission and may be referred to the deficits in learning and memory observed in these mice also before significant plaque load.     

Persistence of systemic mastocytosis after allogeneic bone marrow transplantation in spite of complete remission of the associated myelodysplastic syndrome.

A myelodysplastic syndrome (MDS), type 5 (RAEB-t), and systemic mastocytosis affecting the spleen, the splenic lymph nodes, the bone marrow and the liver were diagnosed in a 38-year-old woman. The clinical course was complicated by splenic vein thromboses and iliac artery embolism. The thrombotic episodes might be secondary to mast cell mediator release. A complete remission of the MDS was obtained by allogeneic bone marrow transplantation, but the mastocytosis persisted. Thus, the possibility that the mast cell originates from a common myeloid precursor cell may be questioned.     

Argon laser stapedectomy using an endo-otoprobe system

In summary, we believe that the endo-otoprobe system offers several advantages to the otologist. The system is safe and relatively inexpensive. The probes are designed to provide tactile feedback similar to that of standard otologic instruments and avoid the use of a cumbersome micromanipulator. There are currently shapes that are similar to a Rosen needle, Shea pick, and bayonet. We hope most otologists will find that one of the endo-otoprobes fits their particular style of surgery.