Genomic, Proteomic and Physiological Characterization of a T5-like Bacteriophage for Control of Shiga Toxin-Producing Escherichia coli O157:H7

Despite multiple control measures, Escherichia coli O157:H7 (STEC O157:H7) continues to be responsible for many food borne outbreaks in North America and elsewhere. Bacteriophage therapy may prove useful for controlling this pathogen in the host, their environment and food. Bacteriophage vB_EcoS_AKFV33 (AKFV33), a T5-like phage of Siphoviridae lysed common phage types of STEC O157:H7 and not non-O157 E. coli. Moreover, STEC O157:H7 isolated from the same feedlot pen from which the phage was obtained, were highly susceptible to AKFV33. Adsorption rate constant and burst size were estimated to be 9.31×10−9 ml/min and 350 PFU/infected cell, respectively. The genome of AKVF33 was 108,853 bp (38.95% G+C), containing 160 open reading frames (ORFs), 22 tRNA genes and 32 strong promoters recognized by host RNA polymerase. Of 12 ORFs without homologues to T5-like phages, 7 predicted novel proteins while others exhibited low identity (<60%) to proteins in the National Centre for Biotechnology Information database. AKVF33 also lacked the L-shaped tail fiber protein typical of T5, but was predicted to have tail fibers comprised of 2 novel proteins with low identity (37–41%) to tail fibers of E. coli phage phiEco32 of Podoviridae, a putative side tail fiber protein of a prophage from E. coli IAI39 and a conserved domain protein of E. coli MS196-1. The receptor-binding tail protein (pb5) shared an overall identify of 29–72% to that of other T5-like phages, with no region coding for more than 6 amino acids in common. Proteomic analysis identified 4 structural proteins corresponding to the capsid, major tail, tail fiber and pore-forming tail tip (pb2). The genome of AKFV33 lacked regions coding for known virulence factors, integration-related proteins or antibiotic resistance determinants. Phage AKFV33 is a unique, highly lytic STEC O157:H7-specific T5-like phage that may have considerable potential as a pre- and post-harvest biocontrol agent

СЛУЧАЙ УСПЕШНОГО ХИРУРГИЧЕСКОГО ЛЕЧЕНИЯ ТРОМБОЭМБОЛИИ ЛЕГОЧНОЙ АРТЕРИИ У БОЛЬНОЙ НА СРОКЕ БЕРЕМЕННОСТИ 11 НЕДЕЛЬ

Pulmonary embolism in pregnant women is fairly common complication, and it remains to be the one of major causes of maternal mortality in the number of countries. The need to compare risks of the mother and child makes the search for optimal treatment tactics very complicated in this specific case. The experience of the last decades provides evidences for choosing aggressive treatment tactics, accurate diagnostics and early surgical intervention. The authors of this article describe the clinical case of successful treatment of the young woman whose pregnancy course was complicated by pulmonary embolism at the 11th week of gestation. The article describes the results of laboratory and instrumental diagnostics and anasthesiological support technique within available scope of pharmacological and technical means. Also the article reviews the literature data on this problem. The conclusion contains recommendations for intra-operative management of such patients. Тромбоэмболия легочной артерии (ТЭЛА) у беременных женщин является весьма частым осложнением, она остается одной из ведущих причин материнской смертности в ряде стран. Необходимость соотнесения рисков для организма матери и ребенка делает поиск оптимальной тактики лечения в данном случае очень сложной задачей. Опыт последних десятилетий свидетельствует в пользу избрания агрессивной тактики лечения, точной диагностики и раннего оперативного вмешательства. В данной статье авторы представляют случай успешного лечения молодой женщины, течение беременности которой осложнилось ТЭЛА на сроке гестации 11 недель. Описываются результаты проведенной лабораторной и инструментальной диагностики, а также методика анестезиологического пособия в рамках доступного объема фармакологических и технических средств. Приводится анализ данных литературы по этой актуальной проблеме. В заключении даны рекомендации по интраоперационному ведению подобных больных.