Is prevalence of PBC underestimated in patients with systemic sclerosis?

BACKGROUND: Clinically significant primary biliary cirrhosis occurs in 2.5% of patients with systemic sclerosis. Primary biliary cirrhosis-specific autoantibodies include anti-mitochondrial, anti-glycoprotein 210, and anti-sp100 antibodies. The majority of asymptomatic anti-mitochondrial-positive subjects express histological features of primary biliary cirrhosis. Early detection of primary biliary cirrhosis is important, as timely introduction of ursodeoxycholic acid may improve prognosis. The aim was to assess the prevalence of MIT3 IgG-anti-mitochondrial, gp210, sp100 and other autoantibodies in patients with systemic sclerosis and compare the clinical and biochemical parameters in those who are primary biliary cirrhosis-specific autoantibodies positive and negative. MATERIALS/METHODS: Fifty-two consecutive patients with systemic sclerosis were included. Thirty-three suffered from limited skin SS and 19 from diffuse SS. RESULTS: Eight (15%) patients with systemic sclerosis tested positive for primary biliary cirrhosis-specific autoantibodies. No significant differences were observed between primary biliary cirrhosis-specific autoantibodies positive and negative subjects in terms of various demographic, clinical or biochemical features. A trend towards increased prevalence of chronic fatigue in primary biliary cirrhosis-specific autoantibodies positive patients was observed. CONCLUSIONS: Primary biliary cirrhosis-specific autoantibodies were detected in 15% of the systemic sclerosis patients. Since patients with primary biliary cirrhosis-specific antibodies are at high-risk or do suffer from primary biliary cirrhosis, screening for primary biliary cirrhosis-specific autoantibodies may be considered during routine assessment of systemic sclerosis.

Steady-state error of a system with fuzzy controller.

We consider the problem of control error of a fuzzy system with feedback. The system consists of a plant, linear or nonlinear, fuzzy controller, and feedback loop. As controller we use both PD and PI fuzzy type controllers. We apply different t-norm and co-norm: logic, algebraic, Yager, Hamacher, bounded, drastic, etc. in the process of fuzzy reasoning. Triangular shape of membership functions is supposed, but we generalize the results obtained. Steady-state error of a system is calculated. We have obtained very interesting results. The steady-state error is identical for pairs of triangular t- and co-norms.

Histiocytosis X of the temporal bone: CT findings.

The preoperative diagnosis of temporal bone histiocytosis X has been based traditionally on clinical examination, plain radiography, and pluridirectional tomography. Clinical misdiagnosis is common because otologic findings can mimic those of acute and chronic infectious ear disease. Similarly, plain radiographic and tomographic findings may be confused with those of mastoiditis, cholesteatoma, and temporal bone metastasis. The three cases of histiocytosis X presented here illustrate the advantages of CT compared with traditional radiographic methods in the diagnosis and staging of this disease. Computed tomography clearly delineates osseous involvement, including erosion of the bony labyrinth. Computed tomography also better defines the soft tissue margins of the granulomatous mass in relationship to the central nervous system and extratemporal tissues.

Relationship of tumor leucocytic infiltration to host defense mechanisms and prognosis.

The interface between the tumor and the host is often the site of leucocytic infiltration. We will examine the idea that the infiltrating leucocytes of human and experimental tumors are components of the host immunological defense against the tumor, and that the presence of the infiltrate is a marker of favorable prognosis. Leucocytes could infiltrate tumors because of an active immune response, either nonspecific or specifically directed to tumor-associated antigens. Leucocyte influx may also occur because of chemotactic factors secreted by the tumor cells. Some tumors release factors which enhance vascular permeability and permit improved access by leucocytes to the tumor focus. The consequences of leucocytic infiltration include tumor cell cytolysis, cytostasis, or stimulation of proliferation. The present state of our knowledge of the interactions between tumor cells and infiltrating leucocytes precludes broad generalization of mechanisms. Further study will probably reveal that the mechanisms are diverse, and that there are some systems in which immune interactions occur at this interface and others in which they do not.