Flame-burned stainless steel wire spheres as carriers of Zymomonas mobilis cells and extracellular levansucrase

In the present work, the use of flame-burned WS as carriers of Z. mobilis and extracellular levansucrase and the effect of the cell fixation method by dehydration on system productivity were investigated. Lyophilization and convective drying of Z. mobilis biomass at 30°C to a moisture content of 10–14% gave the best results for the repeated batch fermentations of a sucrose medium to obtain levan and ethanol. Significant correlation between the product formation and the concentration of free cells in the fermentation medium was established. Clearly, the cells were weakly bound to the newly generated WS and were washed out into the medium during fermentation. Here the hypothesis is presented that components excreted from damaged cells during dehydration can intensify the reactivation of damaged living cells and influence the interactions between the cells and the wire surface. The passive immobilization of extracellular levansucrase in oxidized WS was also observed. The superiority of oxidized WS in comparison with non-treated WS is related to an increase in the number of OH groups. The potential regeneration of WS by burning after the termination of fermentation cycles was also considered.     

Creatine-mediated crosstalk between adipocytes and cancer cells regulates obesity-driven breast cancer

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Cytostatic activity on tumour cells of monocytes from patients with gastrointestinal cancer

Summary The ability of monocytes from patients with gastrointestinal cancer to inhibit tumour cell growth and suppress PHA-induced lymphocyte response in vitro was assessed. Isolated monocytes, i.e., adherent Fc⁺ cells from mononuclear cell suspension, were cytostatic but not cytolytic for both K562 line and L1210 lymphoma cells. Monocytes from the patients showed an increased ability to inhibit the growth of L1210 but not K562 line cells. The increased cytostatic activity of monocytes was associated with their suppressor activity. This suggests that suppressor monocytes are also able to arrest tumour cell growth in vitro.     

Chromosomal localization of a novel repetitive sequence in theChenopodium quinoa genome

In this study, a novel repetitive sequence pTaq10 was isolated from theTaq I digest of the genomic DNA of the pseudocerealChenopodium quinoa. Sequence analysis indicated that this 286-bp monomer is not homologous to any known retroelement sequence. FISH and Southern blot analysis showed that this sequence is characterized by an interspersed genomic organization. After FISH, hybridization signals were observed as small dots spread throughout all of the chromosomes. pTaq hybridization signals were excluded from 45S rRNA gene loci, but they partly overlapped with 5S rDNA loci. pTaq10 is not a species-specific sequence, as it was also detected inC. berlandieri.