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611.
Equilibrium studies of BMXD complexation with copper(II) and glycylglycine were performed by potentiometric and UV-visible titration. The equilibrium constants determined by potentiometry for the ternary system are: [LCu2P3+]/[LCu24+][P]=8.11(3), [LCu2HP4+]/[LCu2P3+][H+]=5.39(2), [LCu2H−1P2+][H+]/[LCu2P3+]=−6.33(2), [LCu2(OH)H−1P+][H+]/[LCu2H−1P2+]=−8.20(1) and [LCu2(OH)2HH−1P][H+]/[LCu2(OH)H−1P−1]=−10.33(3), which are in good agreement with the values determined by UV-visible titration. The species formed were confirmed by electrospray mass spectrometry. The association constants, determined by kinetic studies, for the association of the second molecule of glycylglycine with the LCu2P complex, for two ionic media, are 1.29 (KCl) and 1.27 (KNO3). These are in good agreement with the values determined by thermodynamic measurements 1.41 (KCl) and 1.26 (KNO3).  相似文献   
612.
The data obtained in this study proved that Mycoplasma gallisepticum S6 known as avian pathogen had a phytopathogenic potential. The vegetative forms and the viable but nonculturable (VBNC) forms of this mycoplasma could infect the plants via an assemblage of rootlets, invade different tissues, persist there and cause destructive events characteristic to phytomycoplasmoses. In comparison with the vegetative forms, the VBNC forms induced more prominent destructive changes. This phenomenon might be connected to increasing expression of proteins responsible for virulence in the bacterial cells. The fact that M. gallisepticum S6 could demonstrate virulent features (infectivity, invasiveness, persistence and toxigenicity) in regard to plants seems to require a development of new ways for controlling phytomycoplasmoses taking into account the probable presence of asymptomatic carriers of this bacterium.  相似文献   
613.
So far multiple differences in prostate cancer-specific amino acids metabolism have been discovered. Moreover, attempts to utilize these alterations for prostate cancer diagnosis and treatment have been made. The prostate cancer metabolism and biosynthesis of amino acids are particularly focused on anaplerosis more than on energy production. Other crucial requirements on amino acids pool come from the serine, one?carbon cycle, glycine synthesis pathway and folate metabolism forming major sources of interproducts for synthesis of nucleobases necessary for rapidly proliferating cells. Considering the lack of some amino acids biosynthetic pathways and/or their extraordinary importance for prostate cancer cells, there is a widespread potential for targeted therapeutic applications with no effect on non-malignant cells. This review summarizes the up-to-date knowledge of the importance of amino acids for prostate cancer pathogenesis with a special emphasis on potential applications of metabolic variabilities in the new oncologic paradigm of precision medicine.  相似文献   
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Polycystic kidney diseases (PKDs) are a group of inherited nephropathies marked by formation of fluid-filled cysts along the nephron. Growing evidence suggests that in the kidney formation of cysts and alteration of cystic electrolyte transport are associated with purinergic signaling. PCK/CrljCrl-Pkhd1pck/CRL (PCK) rat, an established model of autosomal recessive polycystic kidney disease (ARPKD), was used here to test this hypothesis. Cystic fluid of PCK rats and their cortical tissues exhibited significantly higher levels of ATP compared to Sprague Dawley rat kidney cortical interstitium as assessed by highly sensitive ATP enzymatic biosensors. Confocal calcium imaging of the freshly isolated cystic monolayers revealed a stronger response to ATP in a higher range of concentrations (above 100 μM). The removal of extracellular calcium results in the profound reduction of the ATP evoked transient, which suggests calcium entry into the cyst-lining cells is occurring via the extracellular (ionotropic) P2X channels. Further use of pharmacological agents (α,β-methylene-ATP, 5-BDBD, NF449, isoPPADS, AZ10606120) and immunofluorescent labeling of isolated cystic epithelia allowed us to narrow down potential candidate receptors. In conclusion, our ex vivo study provides direct evidence that the profile of P2 receptors is shifted in ARPKD cystic epithelia in an age-related manner towards prevalence of P2X4 and/or P2X7 receptors, which opens new avenues for the treatment of this disease.  相似文献   
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Summary Comparative laboratory investigation of two types bioreactors with iron as a carrier of biofilm was made. One was a packed bed reactor and the another was fluidized bed. The results showed that maximum productivity of carrier in fluidized bed bioreactor {7,97 g/m2·d} is two times higher than productivity of carrier in packed bed one {3,45 g/m2·d}.  相似文献   
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