Defining the role of radiosurgery in the management of brain metastases.

The role of stereotactic radiosurgery in the management of recurrent and newly diagnosed brain metastases was evaluated prospectively. From December 1988 to March 1991, 58 lesions in 40 patients were treated with accelerator-based stereotactic radiosurgery. All patients were followed for a minimum of 6 months or to death. The primary purpose was to determine the impact of radiosurgery on local control and its subsequent effects on quality of life. An overall tumor control rate of 82% with a complete response rate of 43% were achieved. As anticipated, the response rate for smaller tumors was substantially better than that for larger tumors (78% for lesions < 2 cm3; 50% for lesions > or = 10 cm3). Although the overall in-field progression rate was 18.5%, only 1/23 (4%) complete responders subsequently recurred. The in-field failure rate is highly comparable with recently published surgical data. Progression outside the brain was noted in two-thirds of patients. One quarter of the deaths were neurologic. The median survival for this minimally selected patient population was 6.5 months. Stereotactic radiosurgery was also associated with improved quality of life as measured by Karnofsky score, neurologic function, and steroid dependence. Long-term steroid dependence was encountered in only four patients. We conclude that stereotactic radiosurgery can be used effectively in patients with brain metastases. In this series, a high tumor response rate was achieved which was associated with improved quality of life.     

Remodeling Adult Nursing

This article describes a nursing education experience in which a critical thinking approach was planned and implemented. Background discussion on critical thinking concepts and related research provides a foundation for presentation of the Mackie teaching model. The model uses a community-based, family-centered scenario as the basis for developing problemfocused nursing intervention skills from a holistic viewpoint. Role expectations of students and faculty are outlined, and related implementation difficulties, together with their resolution strategies, are described. Evaluation methods and outcomes are reviewed in the conclusion.     

Familial lupus anticoagulants

Three families having more than one affected member with SLE or lupus-like disease were investigated by global coagulation tests as well as methods based on dilute thromboplastin, Russell's viper venom and thermal stability/absorption, and by RIA for anticardiolipin (CL) antibodies. Of the 19 persons, 11 had SLE or lupus-like disease. Eight of these 11 had a prolonged KPTT and other evidence of LA, while only 5/11 had high anticardiolipin titres. Four healthy spouses of affected females, and three asymptomatic siblings also had prolonged non-correctable KPTTs. These persons had no bleeding or thrombotic history and normal clotting factor levels. Further clotting tests were negative, although one had raised anti-CL antibody. Such cases may account for some of the patients one finds during routine haemostatic screening with unexplained prolonged KPTT. Although anticardiolipin levels are raised in subjects with LA, there was no close correlation between length of KPTT and anticardiolipin titre. These findings would support a hypothesis of transmissible agents or other environmental factors being involved in lupus-like disorders.     

Radical-mediated damage to parasites and erythrocytes in Plasmodium vinckei infected mice after injection of t-butyl hydroperoxide.

Intravenous injection of t-butyl hydroperoxide rapidly killed Plasmodium vinckei in mice, and caused haemolysis. The same dose seemed harmless to unparasitized mice. Many parasites disintegrated inside circulating erythrocytes, so parasite death was not simply a passive consequence of haemolysis. Injection of desferrioxamine, which removes the traces of free iron that promote the dissociation of t-butyl hydroperoxide into radical species, prevented both parasite death and haemolysis. Lipid peroxidation, as measured by accumulation of malonyldialdehyde over 2 h in vitro, occurred in erythrocytes exposed to t-butyl hydroperoxide, and was particularly marked in erythrocytes from parasitized mice. These erythrocytes accumulated appreciable malonyldialdehyde even without exposure to t-butyl hydroperoxide. Desferrioxamine inhibited the accumulation of malonyldialdehyde, but did not prevent depletion of reduced glutathione by t-butyl hydroperoxide. This suggests that t-butyl hydroperoxide damaged parasites and erythrocytes by dissociating into radical species, rather than by decreasing intraerythrocyte anti-oxidant capacity. In earlier experiments we suggested that intraerythrocytic parasite death and haemolysis caused by alloxan were mediated by radical species, and these experiments with t-butyl hydroperoxide add weight to this interpretation. We regard both of these systems as models for macrophage-induced parasite death and host pathology in acute malaria.     

IMMUNOHISTOCHEMICAL DISTRIBUTION OF CANNABINOID CB 1 RECEPTOR IN THE RAT CENTRAL NERVOUS SYSTEM

IMMUNOHISTOCHEMICAL DISTRIBUTION OF CANNABINOID CB 1 RECEPTOR IN THE RAT CENTRAL NERVOUS SYSTEM@邹冈     

Distribution of fibronectin and laminin in normal and pathological lymphoid tissue.

Forty six lymph nodes were examined with the indirect immunoperoxidase technique for the distribution of fibronectin and laminin. Fibronectin was present in the framework of the tissue and the basal lamina of blood vessels, giving a clear outline of nodal architecture. Intracellular fibronectin was observed in cases of reactive sinus histiocytosis, when about a third of macrophages exhibited strong positivity. Mast cells were positive. A pronounced increase in extracellular fibronectin was seen in nodular sclerosing Hodgkin's disease, although heavily hyalinised areas exhibited only superficial positivity. Reed-Sternberg and mononuclear Hodgkin's cells were consistently negative for fibronectin. Laminin staining was localised to vascular and marginal sinus basement membranes. No cellular positivity was evident. The distribution of laminin indicated a pronounced increase in vascularity in nodular sclerosing Hodgkin's disease, which was especially prevalent within the dense fibrous trabeculae. In contrast, however, examination of the other Rye subtypes showed a lesser degree of vascularity with numbers of vessels similar to those observed in reactive follicular hyperplasia. Laminin was found to be more efficient than factor VIII related antigen as a vascular marker.     

Type IV collagen and laminin staining patterns in benign and malignant cutaneous lesions.

The presence of both laminin and type IV collagen was sought at the dermo-epidermal junction and in the dermis adjacent to benign melanocytic naevi of the junctional, compound, and intradermal types; dysplastic naevi; and both primary and secondary melanoma. In all, 154 lesions were studied, using antibodies to laminin and type IV collagen and an indirect immunoperoxidase technique. The staining patterns seen with the two antibodies were virtually identical, although that of laminin was generally fainter. Breaks in and thinning of the normally continuous line of type IV collagen and laminin at the dermo-epidermal junction were seen in association with the junctional activity of benign naevi, and in malignant melanomas in association with invasive tumour cells. Both benign and malignant cells of the melanocyte series showed relatively light pericellular staining around individual cells and clusters of cells in the papillary dermis. This staining pattern was much stronger in the deeper reticular dermis. It is concluded that the pattern of staining of these two antibodies and in particular the presence of breaks in type IV collagen and laminin at the dermo-epidermal junction are not specific for either benign or malignant melanocytic lesions and cannot be used as a diagnostic marker of invasive malignancy.     

Neutrophil cytochemistry in bacterial infection.

A new cytochemical technique, sensitive to altered lysosomal membrane permeability of blood neutrophils, has been evaluated as a screening test for bacterial infection. This technique, for the lysosomal enzymes acid phosphatase and chloroacetate esterase, was compared with the neutrophil alkaline phosphatase and nitroblue tetrazolium tests. The mean score for each method was significantly higher in infected patients than in normal controls. There was, however, considerable overlap of individual scores between infected patients and ill, but uninfected, patients. This overlap limits the diagnostic value of existing cytochemical screening methods.