Rat ceruloplasmin: a new labile copper binding site and zinc/copper mosaic.

Ceruloplasmin (Cp) is a copper-containing multifunctional oxidase of plasma, an antioxidant, an acute-phase protein and a free radical scavenger. The structural organization of Cp causes its sensitivity to proteolysis and ROS (reactive oxygen species), which can alter some of the important Cp functions. Elucidation of the orthorhombic crystal structure of rat Cp at 2.3 Å resolution revealed the basis for stronger resistance of rat Cp to proteolysis and a new labile copper binding site. The presence of this site appears as a very rare and distinctive feature of rat Cp as was shown by sequence alignment of ceruloplasmin, hephaestin and zyklopen in the Deuterostomia taxonomic group. The trigonal crystal form of rat Cp at 3.2 Å demonstrates unexpected partial substitution of copper by zinc.

Enzymes Regulated via Cystathionine ß-Synthase Domains.

Cystathionine ß-synthase (CBS) domains discovered 20 years ago can bind different adenosine derivatives (AMP, ADP, ATP, S-adenosylmethionine, NAD, diadenosine polyphosphates) and thus regulate the activities of numerous proteins. Mutations in CBS domains of enzymes and membrane transporters are associated with several hereditary diseases. The regulatory unit is a quartet of CBS domains that belong to one or two polypeptides and usually form a conserved disk-like structure. CBS domains function as "internal inhibitors" in enzymes, and their bound ligands either amplify or attenuate the inhibitory effect. Recent studies have opened a way to understanding the structural basis of enzyme regulation via CBS domains and widened the list of their bound ligands.

Inhibition of Escherichia coli Inorganic Pyrophosphatase by Fructose-1-phosphate.

Pyrophosphate regulates vital cellular reactions, and its level in E. coli cells is under the ultimate control of inorganic pyrophosphatase. The mechanisms involved in the regulation of pyrophosphatase activity still need to be elucidated. The present study demonstrated that fructose-1-phosphate inhibits pyrophosphatase activity by a mechanism not involving competition with substrate for binding to the active site. The inhibition constant governing the binding of the inhibitor to the enzyme-substrate complex is 1.1 mM. Substitutions of Lys112, Lys115, Lys148, and Arg43 in the regulatory site completely or partially abolished the inhibition. Thus, Fru-1-P is a physiological inhibitor of pyrophosphatase that acts via a regulatory site in this enzyme.

[Infective endocarditis in patients on program hemodyalisis].

Ten (1.8%) out of 558 patients with end-stage chronic renal failure on program hemodialysis developed infective endocarditis (IE). The average length of hemodialysis before IE was 17.0 +/- 14.5 months. The main cause of IE was infection of the site of vascular approaches. The diagnosis was difficult; Duke criteria modified by J. Li et al. (2000) allowed evidenced diagnosis of IE only in 30% of cases, while modified criteria offered by the authors did it in 50% of cases. The article discusses rational antibacterial therapy. Hospital lethality in IE is as high as 50%.

[Effects of probiotic bifiform on efficacy of Helicobacter pylori infection treatment].

AIM: To study effects of the probiotic bifiform on efficacy of Helicobacter pylori (HP) eradication in patients with chronic gastritis and ulcer disease. MATERIAL AND METHODS: A total of 98 patients with verified HP infection were divided into two groups. The study group received a week three-component anti-HP therapy+a probiotic. The control group received the same treatment without the probiotic. All the patients were tested for HP before the treatment and one month after the end of the treatment. Cell composition of duodenal mucosa (DM), tissue proinflammatory cytokines, secretory immunoglobulin A (sIgA) in coprofiltrates, serum IgA, IgM, IgG, phagocytic parameters and copromicrobiology were studied. RESULTS: HP eradication rate in the study group was higher than in the control group (89.1 vs 63.5, respectively, p < 0.05). After the treatment, patients of the study group had lower rates of side effects, impaired intestinal biocenosis, tissue cytokines levels but higher concentration of plasmatic cells in CO and cIgA in coprofiltrates. CONCLUSION: The addition of probiotic bifiform to the standard three-component antihelicobacter scheme of the treatment raises its efficacy and is promising treatment of HP. Mechanisms of a potentiating action of the probiotic are related to enhancement of antibacterial activity of local immune reactions.

[Status of the upper parts of the digestive tract and Helicobacter pylori infections in patients with chronic kidney failure after kidney transplantation]. / Sostoianie verkhnikh otdelov pishchevaritel'nogo trakta i Helicobacter pylori-infektsiia u bol'nykh khronicheskoi pochechnoi nedostatochnost'iu posle transplantatstii pochki.

The purpose of the study was to examine the state of upper parts of the digestive tract, prevalence of Helicobacter pylori infection and its relation to the pathology revealed in patients with chronic renal insufficiency after kidney transplantation.

[Use of pyelo-cystic anastomosis in ureteral obliteration after kidney transplantation]. / Primenenie pielotsistoanastomoza pri obliteratsii mochetochnika posle transplantatsii pochki.

Reconstruction of the urinary tract because of ureteral stricture after kidney transplantation is a serious problem. In development of obliteration of the recipient's ureter near anastomosis and in the absence of own ureters reconstruction is made by pyelocystoanastomosis. A case is reported of a successful use of this method in reconstruction of the urinary tract. Preoperative preparation includes transcutaneous nephrostomy. Sometimes Boary flap is used. The arising reflux had insignificant effect on the transplant's function.