Serial magnet resonance angiography in patients with vasculitis and vasculitis-like angiopathy of the central nervous system

The purpose of the study was to examine the value of the non-invasive magnet resonance angiography (MRA) in the follow-up of cerebral vasculitis (CV) and vasculitis-like angiopathy. We performed follow-up MRA (TOF 3D), MRI and transcranial doppler ultrasound (TCD) in the patients with isolated angiitis of the CNS (2/6), Crohn-disease-associated CV (1/6), and reversible arterial vasoconstriction (RAV) of the CNS (1 migraine, 1 eclampsia and 1 toxic encephalopathy) (3/6). In all patients with RAV MRA showed a complete remission of the vascular alterations after treatment. In the patients with isolated angiitis of the CNS and Crohn-disease-associated CV, partly regressive and partly progressive changes were demonstrated. The MR-angiographically detectable vascular alterations corresponded to the clinical course of the disease, as well as to TCD in all our patients. Success of therapeutic procedures, the need and the intensity of further drug administration could be estimated. The MRA appears to be a valuable non-invasive method in the follow-up of patients with CV and RAV.     

Expression of chemokine receptors by cancer cells

Chemokine receptors are involved in the trafficking of leucocytes. It has been shown recently that chemokine receptors (CXCR4, CCR7...) are expressed by breast cancer cells and could be involved in the metastasis phenomenon. Since this discovery, new data have been generated in this topic. These data confirm that chemokine receptors are involved in the occurrence of metastases, suggest that their expression is regulated by genes involved in the carcinogenesis and/or angiogenesis (VHL...) and that inhibitors could be of interest in the treatment of breast cancer. In this paper, we will review all these data and will discuss the perspectives that opens this new concept.     

Progression of subjective refraction after artificial divergence surgery and its relation to a possible myopic spasm

PURPOSE: To study the effect on subjective refraction of artificial divergence surgery in congenital nystagmus with blocking convergence. METHODS: Retrospective study on 139 cases, with a study of visual acuity and optical correction with habitual glasses 1-5 years after operation, according to age and ocular alignment (orthophoria or exophoria). RESULTS: Increased myopia with glasses of approximatively 1 diopter, but likely to be due to eye growth in this young population (mean age, 14 years). This myopic shift is higher in the exophoric population, but there is a tendency to prescribe a stronger correction to help control the phoria. A few rare cases of true myopic spasm were noted. CONCLUSION: After artificial divergence surgery, true cases of increased myopia were rare. Tonic vergence is stronger than accommodative vergence.     

Liver imaging with MDCT and high concentration contrast media

Liver imaging has advanced greatly over the last 10 years with helical CT capability and more recently the addition of multidetector-row CT (MDCT). Multidetector CT technology facilitates imaging at faster speeds with improved image quality and less breathing artifact [Abdom. Imaging 25 (2000) 643]. Exquisite three-dimensional data sets can be obtained with thin collimation providing improved lesion detection, multiplanar imaging, and the ability to perform CT angiography of the liver and mesenteric vessels. New challenges arise with this advance in technology including safety considerations. The radiation dose to the patient has increased with MDCT and this is compounded by the ability to perform multi-phase liver imaging. Furthermore, issues of contrast media administration require reconsideration including optimal timing and rate of administration, the total volume of contrast needed and the ideal iodine concentration of the contrast media. Recently, the use of high concentration contrast media (HCCM) has been explored and study results to date will be reviewed.     

Computer-assisted generation of all-ceramic crowns and fixed partial dentures

The successful application of the concept of computer-assisted manufacturing in restorative dentistry requires that computer-assisted design (CAD) and computer-assisted machining (CAM) not only meet but actually exceed currently accepted standards for the material and clinical quality of dental restorations. In addition, the continued development of systems for polyvalent processing of disparate materials and objects must be assured. With these critical requirements in mind, the Precident system is a clinically proven and competitive system. The resolving power of the CCD chip is much improved compared to conventional cameras or charge-coupled devices. The scanner is able to scan entire casts in a fully automated process. In principle, this facilitates the production of frameworks for fixed prosthetic devices (FPD) of any size. It is also possible to create at least partial frameworks for removable prosthetic devices (RPD). A factor of great clinical and economic importance is the polyvalence of the process in materials processing: the numeric control (NC) machine can be programmed for metal alloys and ceramic materials as well as fiber-reinforced resins. At Aeskulap Klinik, the Precident System is routinely used for producing all single crowns and FPDs with up to four units. CAD/CAM all-ceramic crowns and FPDs currently cost about the same as metallo-ceramic or conventional all-ceramic restorations.     

c-myc, p53 and bcl-2, apoptosis-related genes in infiltrating breast carcinomas: evidence of a link between bcl-2 protein over-expression and a lower risk of metastasis and death in operable patients

Apoptosis is an important physiological process controlled by multiple genes, including c-myc, p53 and bcl-2, and its inhibition may lead to the development of human cancers. In this study, we analyzed expression of the c-myc gene using Northern blot and of the p53 and bcl-2 proteins by immuno-histochemistry in 175 breast tumor specimens obtained from patients with operable breast cancer. We evaluated the relation between expression of these 3 genes and (i) the main usual prognostic factors (tumor size, histo-prognostic grade, hormone receptors and number of positive nodes); (ii) the risk of death and relapse, taking into account these 4 factors, after a mean period of follow-up of 9.5 years (SD 2 years). Over-expression of c-myc, p53 and bcl-2 was observed in 35%, 23% and 63% of tumors, respectively. Over-expression of c-myc was strongly linked to the number of positive nodes (p = 0.0005). p53 protein expression was associated with both high-grade (p = 0.0001) and hormone receptor-negative (p = 0.0001) tumors. In contrast, bcl-2 protein over-expression was associated with the main favorable prognostic factors and, more particularly, with hormone receptor-positive tumors (p = 0.0001). Multivariate analysis, using the Cox model, showed that only 2 factors were independently linked to the risk of death: number of positive nodes, which increased the risk (p = 0.0001), and bcl-2 protein over-expression, which decreased the risk (p = 0.008). When bcl-2 over-expression was studied in relation to nodal status, hormone receptor status and chemo- and hormone therapy, no significant difference was observed between different subgroups of patients. bcl-2 expression was also associated with a significantly lower risk of distant metastasis (p = 0.04). In conclusion, bcl-2 expression characterizes a particular phenotype of breast cancer with a favorable prognosis, and it may therefore be used as a marker of long-term survival. Int. J. Cancer (Pred. Oncol.) 84:562-567, 1999.     

Relationship between the chest radiograph, regional lung function studies, exercise tolerance, and clinical condition in cystic fibrosis

This study evaluated the accuracy of the interpretation of the chest film in delineating localised abnormalities of ventilation and perfusion, as well as the overall severity of airways obstruction, exercise tolerance, and clinical condition in children with cystic fibrosis. Radiographic findings in various regions of the chest film were compared with the functional values obtained with regional lung function tests which evaluated the arrival and disappearance of boluses of radioactive nitrogen given by inhalation and infusion. While the more severely affected areas on the chest radiograph were found to correlate with similar regions on the lung function tests, as did overall scores, errors occurred in some cases if the x-ray film alone was used as a judge of regional physiological derangement. In addition the degree of airways obstruction, the exercise tolerance on a cycle ergometer, and clinical grading, each correlated significantly with the radiographic score. We conclude that the chest radiograph is a good indicator of the overall severity of the lung disease and that it correlates well with exercise tolerance and clinical condition in cystic fibrosis.     

Development of prediction models for three in vitro embryotoxicity tests in an ECVAM validation study

Since 1997 the National Center for Documentation and Evaluation of Alternative Methods to Animal Experiments, ZEBET, in Berlin, has been coordinating a validation study aimed at prevalidation and validation of three in vitro embryotoxicity tests, funded by the European Center for the Validation of Alternative Methods (ECVAM) at the Joint Research Center (JRC, Ispra, Italy). The tests use the cultivation of postimplantation rat whole embryos (WEC test), cultures of primary limb bud cells of rat embryos (micromass or, MM, test), and cultures of a pluripotent mouse embryonic stem cell line (embryonic stem cell test or EST). Each of the tests was performed in four laboratories under blind conditions. In the preliminary phase of the validation study 6 out of 20 test chemicals comprising different embryotoxic potential (non, weakly, and strongly embryotoxic) were tested. The results were used to define biostatistically based prediction models (PMs) to identify the embryotoxic potential of test chemicals for the WEC test and the MM test. The PMs developed with the results of the preliminary phase of the validation study (training set) will be evaluated with the results of the remaining 14 test chemicals (definitive phase) by the end of the study. In addition, the existing, improved PM (iPM) for the EST, which had been defined previously, was evaluated using the results of the preliminary phase of this study. Applying the iPM of the EST to the results of this study, in 79% of the experiments, chemicals were classified correctly according to the embryotoxic potential defined by in vivo testing. For the MM and the WEC test, the PMs developed during the preliminary phase of this validation study provided 81% (MM test) and 72% (WEC test) correct classifications. Because the PM of the WEC test took into account only parameters of growth and development, but not cytotoxicity data, a second PM (PM2) was developed for the WEC test by incorporating cytotoxicity data of the differentiated mouse fibroblast cell line 3T3, which was derived from the EST. This approach, which has previously never been used, resulted in an increase to 84% correct classifications in the WEC test.