Non-Hodgkin lymphoma of the central skull base: MR manifestations

OBJECTIVE: The aim of this study was to demonstrate the MR characteristics of non-Hodgkin lymphoma of the skull base to help in the differential diagnosis of this neoplasm from other conditions. MATERIALS AND METHODS: MR of five patients, 7-64 years old, with pathologically proved lymphomas of the skull base were reviewed. Three cases had primary skull base lesions involving the sphenoid bone and the cavernous sinus. One case with a nasal cavity lesion involving the skull base and one with a relapsing skull base lesion of previously treated tonsillar lymphoma were included. RESULTS: The lesions had signal intensities that were similar to that of gray matter of brain on both T1- and T2-weighted imaging. Bilateral cavernous sinuses were involved with encasement of internal carotid arteries in every case. Postcontrast MR showed homogeneous enhancement of the tumor with dural infiltration along the planum sphenoidale, clivus, or tentorium. The clivus was destroyed or replaced by tumors in adult cases but in two children the clivus was preserved with intact sphenooccipital synchondrosis. In one case the tumor extended to the extracranial portion through the jugular foramen. CONCLUSION: The MR findings of a permeative lesion of the skull base, invasion of the cavernous sinus without arterial narrowing, infiltration along the dural surface, and an iso- or hypointensity with brain on T2-weighted imaging should suggest lymphoma.     

Information systems and uncertainty: a conspiracy of misplaced confidence

Abstract. Information technology is becoming an increasingly important factor in contemporary management. Information systems are being set up in business explicitly to accommodate the new opportunities of this technology, and these are having a lasting effect on managerial practice. The full implications of this technology-driven development have not been appreciated by organizations, which in absorbing technological systems, are tolerating a great drain on their resources.
The efficacy of computers is predicated on the acceptance of some very specific perspectives. A growing discontent and disappointment with their limited achievements is our reason for advocating a different point of view. We will discuss how a shift in perspective, particularly in respect to the perception of uncertainty, will affect thinking and practice in the field of management support systems. We will render our view of the application of computerized decision support systems (DSS), and especially, we will focus on the beliefs and assumptions that have shaped this technology thus far. To this end we will discuss the concept of uncertainty, by juxtaposing current thinking and practice with our understanding of the context of its application. Finally, we will place our understanding of uncertainty in a managerial context and explain the implications this would have for strategists.     

Imaging of follicular dendritic cell tumours of the liver

Follicular dendritic cell tumour of the liver is a recently recognized entity. To date, only two cases have been described, both in the pathology literature. Histologically, it resembles an inflammatory pseudotumour and immunohistochemical and ultrastructural studies are required for its diagnosis. The ultrasound, computed tomography and angiographic features of two cases of follicular dendritic cell tumour of the liver are described in detail. One of the patients had multiple recurrences of this tumour. The imaging features are very similar to those of hepatocellular carcinoma. As follicular dendritic cell tumour is considered to be of low-grade malignant potential, in contrast to the dismal prognosis for hepatocellular carcinoma, it is important to be able to accurately distinguish between the two types of tumour prior to initiating definitive therapy.     

Simulation of glasses and glass-forming liquids after two decades: some perspectives

We comment on the current status of molecular dynamics and ion dynamics computer simulation studies with respect to advances in understanding of glass formation from viscous liquids, and suggest a classification of current glass and viscous liquid problems in terms of their accessibility to study by computer simulation methods, giving examples in each class. In class C are the problems which are accessible with modest computing facilities and one case, in which the fragility of alternative polymorphic forms of vitreous SiO₂ is assessed, is treated in some detail.     

Coping styles associated with psychological adjustment to advanced breast cancer.

The aim of this study was to determine whether psychological adjustment to advanced breast cancer was positively associated with expressing emotion and adopting a fighting spirit and negatively associated with denial and fatalism. Total mood disturbance on the Profile of Mood States was used as the measure of psychological adjustment. The Courtauld Emotional Control Scale measured emotional expression, and the Mental Adjustment to Cancer measured fighting spirit, denial, and fatalism. The sample included 101 women with a diagnosis of metastatic or recurrent breast cancer. Fighting spirit and emotional expressiveness were found to be associated with better adjustment. No association was found between mood disturbance and denial or fatalism. Because this was a cross-sectional study, no conclusions regarding a causal relationship between adjustment and emotional expressiveness or adjustment and fighting spirit were possible. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Isolation and identification of Mycobacterium cultures antagonistic to phytopathogenic microflora

The immunosuppressive activity of extracellular and water-phenol lipopolysaccharides (LPS) of S.minnesota in S- and R-forms, as well as their gel-filtration, polysaccharide and lipid fractions, was studied in mouse experiments on the model of delayed type hypersensitivity (DTH). The study revealed that the extracellular LPS of S-form S.minnesota was capable of suppressing DTH with lipid A playing the decisive role in this immunosuppressive activity. The extracellular LPS of Reform S.minnesota did not possess the capacity for immunosuppression, but acquired it after redox treatment.     

Inorganic chloride and mixed halide glasses with low maximum phonon frequencies

A class of inorganic chloride glasses based on BiCl₃ as glass-former is described, and their glass transition temperatures reported. They are characterized by infra-red transparency to unusually long wavelengths.