[Endoscopic stenting for malignant pancreatobiliary strictures]. / Endoskopicheskoe stentirovanie pri opukholevykh strikturakh pankreatobiliarnoi zony.

OBJECTIVE: To improve the outcomes in patients with malignant obstructive jaundice using intraluminal stenting. MATERIAL AND METHODS: The present study included 62 patients with clinical symptoms of malignant obstructive jaundice. In the main group, we performed biliary stenting with self-expanding multi-perforated stents (Hanarostent Multi-hole Biliary). Microscopic perforations of these stents prevent migration and reduce the risk of blocking the cystic and main pancreatic ducts. In the control group, stenting was performed with fully and partially covered self-expanding stents. RESULTS: Lower incidence of obstructive cholecystitis and acute pancreatitis in the main group was associated with multiperforated stents reducing the risk of blocking the main pancreatic and cystic ducts. CONCLUSION: In our study, multiperforated stents excluded migration and reduced the incidence of complications (acute cholecystitis from 11.5 to 3.8%, acute pancreatitis from 15.3 to 7.7%).

[Mutational analysis of the CytR protein binding site within the regulatory region of Escherichia coli udp gene]. / Mutatsionnyi analiz osnovnogo saita sviazyvaniia belka CytR v regu liatornoi oblasti gena udp Escherichia coli.

Site-specific mutagenesis of the pentameric motif TGCAA within the regulatory region of the udp gene with coordinates -68 and -64 relative to the transcription initiation site was performed. Nine mutant promoters containing multiple nucleotide base-pair substitutions in this pentameric motif were isolated and characterized. One mutant contained a deletion of the C/G nucleotide pair in the -66 position. Isolated mutant promoters were cloned into a low-copy-number expression vector pJEL250 to determine the level of their expression, depending on the allelic state of cytR and cya genes. The level of CytR-dependent regulation of the udp gene and the ability to titrate the CytR repressor in vivo were shown to be drastically decreased in all mutant promoters isolated. On the basis of these results, it is concluded that the pentameric motif TGCAA plays a key role in binding the CytR repressor protein to the udp gene promoter.