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BACKGROUND: In many countries, gastric cancer is not diagnosed until an advanced stage. An Internet-based e-learning system to improve the ability of endoscopists to diagnose gastric cancer at an early stage was developed and was evaluated for its effectiveness. METHODS: The study was designed as a randomized controlled trial. After receiving a pre-test, participants were randomly allocated to either an e-learning or non-e-learning group. Only those in the e-learning group gained access to the e-learning system. Two months after the pre-test, both groups received a post-test. The primary endpoint was the difference between the two groups regarding the rate of improvement of their test results. FINDINGS: 515 endoscopists from 35 countries were assessed for eligibility, and 332 were enrolled in the study, with 166 allocated to each group. Of these, 151 participants in the e-learning group and 144 in the non-e-learning group were included in the analysis. The mean improvement rate (standard deviation) in the e-learning and non-e-learning groups was 1·24 (0·26) and 1·00 (0·16), respectively (P<0·001). INTERPRETATION: This global study clearly demonstrated the efficacy of an e-learning system to expand knowledge and provide invaluable experience regarding the endoscopic detection of early gastric cancer (R000012039).

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AIMS: The feasibility of the continuous production of a valuable bioplastic raw material, namely 1,3-propanediol (1,3-PDO) from biodiesel by-product glycerol, using immobilized cells was investigated. In addition, the effect of hydraulic retention time (HRT) was also analysed. METHODS AND RESULTS: Ceramic balls and ceramic rings were used for the immobilization of a locally isolated strain; Klebsiella pneumoniae (GenBank no. 27F HM063413). HRT of 1 h is the best one in terms of volumetric production rate (g 1,3-PDO l(-1) h(-1)). The results indicated that ceramic-based cell immobilization achieved a 2-fold higher production rate (10 g 1,3-PDO l(-1) h(-1)) in comparison with suspended cell system (4·9 g 1,3-PDO l(-1) h(-1)). CONCLUSIONS: Continuous cultures with immobilized cells revealed that 1,3-PDO production was more effective and more stable than suspended culture systems. Furthermore, cell immobilization had also obvious benefits especially for resistance of the production for extreme conditions (high organic loading rates, cell washouts). The results were important for understanding the significance of continuous immobilization process among other well-known 1,3-PDO fermentation processes. SIGNIFICANCE AND IMPACT OF THE STUDY: This work is a promising process for further studies, as the immobilized micro-organism was able to reach high volumetric production rates at short HRT, it has an important role in tolerating and converting glycerol during fermentation. Therefore, HRT is a very significant operational parameter (P value <0·05) directly affecting the bioreactor performance and production rate.

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Herpes simplex virus (HSV) causes life-threatening infections in immunocompromised patients such as transplant recipients and patients with hematologic malignancies. We herein describe the case of a patient with chronic myeloid leukemia blastic transformation who developed severe herpetic tonsillitis complicated by tonsillar abscess formation. Abscess formation was determined by computed tomography, whereas tonsillitis due to HSV was confirmed by pathologic and immunohistochemical examinations of the tonsillar biopsy. For molecular confirmation, HSV DNA was amplified by LightCycler PCR and type (HSV-1) determined by melting point analysis. The patient responded promptly to antiviral treatment and there were no signs of recurrent infection at the follow-up. To our knowledge, this case is unique for being the first case of tonsillar abscess formation due to HSV-1, also emphasizing the importance of herpetic infections in the differential diagnosis of oropharyngeal small-sized lesions in the immunocompromised patient population.

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The aim of the present study was to investigate the effect of nitric oxide (NO) on the relaxant activity of caffeine and aminophylline on rat myometrial strips. Uteri of pregnant Wistar rats were removed and suspended in 10-ml organ baths containing 37 degreesC Krebs bicarbonate solution gassed with 95% O2 and 5% CO2. The significance of the results was assessed by Student's t-test and P<0.05 was considered significant. A relaxant effect was observed with 10(-5)-10(-2) M caffeine (n=8) and aminophylline (n=6) on pregnant rat myometrial strips precontracted with 64 mM K+ (IC50=4.21+/-0.35 and 4.25+/-0.26, respectively). Incubation with 10(-5) M methylene blue, 10(-5) M haemoglobin, 10(-6) M Nomega-nitro-L-arginine methyl ester (L-NAME), 2x10(-7) M forskolin and 10(-6) M zaprinast exerted no effect on the relaxations (P>0.05). When the concentration of external Ca2+ was decreased to 0.5 mM or increased to 4.5 mM from the control level of 1.5 mM, the concentration-inhibition curves for caffeine and aminophylline shifted to the left or to the right, respectively. Our results suggest that: (1) the L-arginine-NO-cGMP system has no effect on the inhibition induced by caffeine and aminophylline on K+ induced contractions of pregnant rat myometrium; (2) this inhibitory effect is not mediated by cAMP; (3) cGMP does not play a role on the relaxant effect of these drugs; and (4) that Ca2+ plays the major role on the relaxations obtained with methylxanthine derivatives on pregnant rat uterus. (c) 1998 The Italian Pharmacological Society.

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