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OBJECTIVE: Differences of attenuation and enhancement patterns in focal nodular hyperplasia and hepatocellular adenoma were evaluated and quantified using triphasic single-slice helical CT. MATERIALS AND METHODS: Forty-five histologically proven focal nodular hyperplasias in 27 patients and 18 hepatocellular adenomas in six patients were examined with helical CT. Quantitative evaluation included the following: attenuation of lesions, scar, and liver parenchyma during unenhanced, arterial (20 sec after injection), and portal venous phases (70 sec after injection); relative enhancement of lesions and liver (the ratio between attenuation in arterial phase and portal venous phase, respectively, and attenuation in unenhanced phase); and the prevalence of scar and its central vessel in focal nodular hyperplasia. RESULTS: The study showed no significant difference between mean attenuation values of focal nodular hyperplasia (mean +/- SD, 51.2 +/- 5.9 H) and hepatocellular adenoma (mean +/- SD, 56.3 +/- 7.8 H) in the unenhanced phase. In the arterial phase attenuation values were significantly higher in focal nodular hyperplasia (mean +/- SD, 117.9 +/- 15.1 H) than in hepatocellular adenoma (mean +/- SD, 80.1 +/- 10.5 H). In the portal venous phase no significant differences in attenuation values were detected between focal nodular hyperplasia (mean +/- SD, 112.1 +/- 20.4 H) and hepatocellular adenoma (mean +/- SD, 110.2 +/- 12.9 H). For enhancement parameter thresholds separating focal nodular hyperplasia from hepatocellular adenoma, the following were found: the relative enhancement was higher in 100% of the focal nodular hyperplasias and lower than or equal to 1.6 (accuracy, 96%) in 87% of the hepatocellular adenomas. CONCLUSION: Triphasic helical CT combined with quantitative evaluation of liver lesions offers the possibility of detecting differences in liver lesions that are visually similar on CT. The attenuation and relative enhancement in the arterial phase show significant differences that make accurate differentiation between focal nodular hyperplasia and hepatocellular adenoma possible.

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Extracts from the leaves of the Gingko tree (Ginkgo biloba L.) are therapeutically used for the treatment of peripheral and cerebral vascular disorders as well as multi-infarct or Alzheimer-type dementia. As constituents with potential contact allergenic and toxic properties in crude Ginkgo extracts a group of alkylphenols (e.g., ginkgolic acids, ginkgol, bilobol) has been described. Thus, for reasons of drug safety a maximal concentration (< or = 5 ppm) of ginkgolic acids is requested by the Monograph of the Commission E of the former German Federal Health Agency (Bundesgesundheitsamt, BGA). During production of the standardized Ginkgo extract EGb 761, alkylphenols are largely eliminated as water insoluble compounds (decanter sludge) from the primary acetone extract. To further assess the adverse properties of alkylphenols, different fractions derived from the decanter sludge were evaluated for their embryotoxic effects in the hen's egg test (HET). A fraction enriched for ginkgolic acids (16%) and biflavones (6.7%) was found to induce death of 50% of the chick embryos (LD50) at a dose of 1.8 mg/egg (approximately/= 33 ppm). A similar strong lethal effect (LD50: 3.5 mg/egg; 64 ppm) was oberserved for a fraction which contained 58% ginkgolic acids but less than 0.02% biflavones. In contrast, an extreme low toxic potential (LD50: 250 mg/egg or 4540 ppm) was established for a fraction containing 16% biflavones and 1% ginkgolic acids. Thus, the present investigations confirm the high toxic potential of ginkgolic acids, although it can not be excluded that biflavones or some other constituents in the different fractions may amplify the adverse effect of these substances. Since no contribution of alkylphenols to the therapeutic efficacy of Ginkgo extracts has been confirmed and their elimination during the manufacturing process does not cause technical problems, these results further support the requirement for the completest possible removal of these compounds under toxicological considerations.

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This paper presents a hybrid-unsupervised and supervised-classifier for land use classification of remote sensing images. The entire satellite image is quantized by an unsupervised Neural Gas process and the resulting codebook is labeled by a supervised majority voting process using the ground truth. The performance of the classifier is similar to that of Maximum Likelihood and is only a little worse than Multilayer Perceptions while training and classifying requires no expert knowledge after collecting the ground truth. The hybrid classifier is much better suited to classifications with complex non-normally distributed classes than Maximum Likelihood. The main advantage of the Neural Gas classifier, however, is that it requires much less user interaction than other classifiers, especially Maximum Likelihood.

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HLA-DR locus antigens were studied in a large population of Black Americans with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). An association was found with DR4 in RA (p less than 0.001) and DR3 in SLE (p less than 0.01). Our findings are similar to those reported in Caucasians. No significant correlations between clinical manifestations and DR locus antigens were apparent in either disease. Our results support the association of D locus antigens with disease susceptibility more than with clinical severity.

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Reiter's syndrome was found in three men who presented with cardiac conduction disturbances. In two patients, Reiter's syndrome had been present for more than 30 years and had been previously unrecognized. These patients included a 67 year old man with complete heart block of 13 years' duration, and his son, who had left bundle branch block and chronic generalized cardiomyopathy. A chart review of 19 other patients with Reiter's syndrome who were seen at this institution disclosed five patients with conduction abnormalities. Transient first-degree heart block was the most common disturbance detected and was usually associated with active Reiter's syndrome. Some conduction abnormalities appeared after a long latent period at a time when other manifestations of Reiter's syndrome were inactive. An association with this disorder was therefore not obvious. In all five patients with Reiter's syndrome and conduction disturbances, testing for B27 antigen gave positive results. Both clinical and histopathologic changes in the heart in Reiter's syndrome are analogous to those in ankylosing spondylitis, also associated with B27 antigen. We suggest that the heart, like the joints and iris, may be a target organ for B27-associated disease by a mechanism that remains to be defined.

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A 21-year-old woman with systemic lupus erythematosus (SLE) had meningismus, conjunctivitis, lymphadenopathy, and elevation of liver function values following ibuprofen therapy. All symptoms and laboratory value abnormalities resolved rapidly when the drug therapy was stopped. Two years later, a similar reaction occurred after taking tolmetin sodium. Fever, adenopathy, aseptic meningitis with a polymorphonuclear pleocytosis, and serum transaminase level elevations resolved rapidly after use of the drug was discontinued. The mechanism of this reaction to nonsteroidal antiinflammatory drugs in patients with SLE is not known.

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We present a patient with Yersinia enterocolitica septicemia who relapsed after a course of apparently appropriate antibiotic therapy. A literature review of successfully managed patients with this infection suggests clinical efficacy of aminoglycosides if therapy is continued for at least two weekon are presented. Close follow-up after therapy is required for early recognition and prompt treatment of relapse.

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