We determined the surface-associated proteolytic activity in three Entamoeba histolytica Schaudinn, 1903 strains (monoxenic HM1, axenic HM1, and HK9) of known virulence and its relationship with collagenase activity. Both activities were also determined in axenic HM1 amoebae trophozoites which were sensitive and resistant to complement-mediated lysis. Surface proteolytic activity was determined in glutaraldehyde-fixcd E. histolytica trophozoites, which degraded the insoluble substrate, hide powder azure, and cleaved the human immunoglobulin G heavy chain in a time-dependent fashion, at neutral pH, in presence of 2-mercaptoethanol as cysteine protcase activator. Surface proteolytic activity was strain dependent: monoxenic HM1 > axenic IIM1 > axenic HK9. This activity correlated with collagenolytic activity (p < 0.05). Acquisition of resistance to complement-mediated lysis by axenic HM1 strain did not modify either surface proteases or collagenase expression. Our results suggest that this surface proteolytic activity could be used as an in vitro virulence marker for E. histolytica.
Chlorophyll (Chl) biosynthesis intermediate compounds (like protoporphyrin-IX, Mg-protoporphyrin methyl ester and protochlorophyllide), Chl {a + h), heme, cytochrome P-450 (cyt P-450) and lipid peroxide levels as well as the activities of superoxide dismutase, catalase and lipoxygenase were studied in selenium treated mung beán seedlings. Chl (a -t- b) content and heme levels were decreased with a concomitant accumulation of all the three porphyrins studied. Se treatment enhanced the lipoxygenase activity and correspondingly increased lipid peroxide levels. Se inhibited both the antioxidant enzymes catalase and superoxide dismutase in a dose- dependent manner. However, cyt P-450 levels were enhanced under Se exposure. Hence the inhibitory effect of Se on Chl synthesis is not only by acting on constituent biosynthetic enzymes but also through lipoxygenase-mediated lipid peroxide levels and inhibition of antioxidant defence component systém.
Der Aufsatz befasst sich mit dem Vergleich von zwei Konzeptionen des literarischen Werks, die am Ausgang des 20. Jahrhunderts sehr einflussreich wurden. Der Vergleich betrifft den „Akt des Lesens“ (Wolfgang Iser), der im „Textspiel“ seinen Höhepunkt erreicht, und den Entwurf der „produktiven Referenz“ (Paul Ricoeur). Die letzgenannte Konzeption unterscheidet sich von der zuerst genannten durch eine eigenartige Auffasung von „Mimesis“, doch sie ist (in der „Lebendigen Metapher“ sowie in „Zeit und Erzählung“) ebenfalls auf die Bedeutungen der Welt gerichtet, die im literarischen Werk durch die kreative Kraft der Sprache neu gestaltet wird.
Two of 98 native littleneck clams, Protothaca staminea Conrad, from Cooper’s Cove, Sooke Basin were infected with an eimeriorin coccidian parasite. Merogonic, gamontogonic and sporogonie development were observed in renal tubular epithelial cells. Sporulation of the oocysts occurred within the host. Mature oocysts were spherical mean 41 pm (range 30-44), and contained about 32 subspherical sporocysts (9 x 10 pm), each of which contained 4 sporozoites. Spherical 19 pm (18-20), cyst-like structures and smaller multinucleate bodies, some of which resembled sporocysts, were also seen.A review of the coccidian parasites of bivalves led to the erection of the new genus, Margolisiella (family Eimeriidae Minchin, 1903) to accommodate M. kabatai sp. n., the parasite in Protothaca staminea described herein. Four previously described monoxenous species (Pseudoklossia patellae Debaisieux, P. chitonis Debaisieux, P. tellinovum Buchanan and P. halintis Friedman, Gardner, Hedrick, Stephenson, Cawthom et Upton) were also transferred to the new genus. The 2 remaining possibly heteroxenous species (P. pelseneeri Léger and P. glomerata Léger et Duboscq) were retained in the genus Pseudoklossia Léger et Duboscq (family Aggregatidae Labbé, 1899).
The most general concept in Miloš Dokulil’s theory of word-formation is the idea of ''onomasiological category''. But one of the most cogent parts of his theory, unfortunately one which has left little significant imprint on research in word-formation and its description, is the theory of productivity. In this brief survey, I concentrate on Miloš Dokulil’s distinguishing between empirical productivity and systemic productivity. and Teorie tvoření slov Miloše Dokulila patřila ve své době ke špičkovému výkonu ve sféře lingvistiky. Soudobé výzkumy zákonitostí utvářenosti a nového tvoření slov vycházející z práce s velkými elektronickými korpusy mohou na teoretické závěry a postuláty Miloše Dokulila dobře navazovat, ověřovat je, korigovat a dále užitečně rozvíjet. Jedním z nejplodnějších pojmů Dokulilovy teorie je jeho teorie slovotvorné produktivity a rozlišení produktivity systémové od produktivity empirické. Právě na tyto aspekty Dokulilovy teorie slovotvorné produktivity je tento stručný přehled soustředěn.
Net photosynthetic rate {P^) of Brassica carínata strains, synthesized froin the reciprocal cytoplasms, i.e. B. carinata-226 (B. nigra x B. oleracea) and naturally occurring B. carínata which cairies B. nigra cytoplasm, was relatively less susceptible to moisture stress than the strain B. carinata-24i synthesized from B. oleracea cytoplasm. The contiibution of higher ability inherited from the B. nigra parent and higher water status inherited from the B. oleracea parent resulted in drought resistance of B. carinata-226. B. carinata-24\, synthesized from reciprocal cytoplasm was, however, not able to maintain the high water status and thus was vulnerable to moisture stress.