ABSTRACT
During the development of bacteria-based biotechnology, bacteriophage infection is one of the constant threats and troublesome problems in industrial fermentation. The core of puzzled bacteriophage infection is a complex arm race of coevolution between bacteriophages and their hosts where bacteriophage has evolved lots of escaped ways against bacterial resistance mechanisms. The strategies of rationally designing factories and rotation of starter strains could reduce the risk of bacteriophage infection, but often fail to avoid. Genetic engineering to increase bacterial resistance is one of the strategies to prevent bacteriophage infection and more knowledge about bacteriophage and its host is needed. Recently, there are some new findings on bacterial resistance mechanisms which provide new solutions for bacteriophage infection. For example, it is possible for a rational design of resistant strains to use CRISPR-Cas based technologies just based on the sequences of bacteriophages. Moreover, it is also possible to avoid the escape of bacteriophage by iteratively building up resistance levels to generate robust industrial starter cultures. Quorum-sensing signal molecules have recently been proved to be involved in the interactions between bacteria and bacteriophages, which provides a possible way to solve bacteriophage infection from a population level. Finally, the rapid development of bacteriophage genome editing and synthetic biology will bring some new cues for preventing bacteriophage infection in industrial fermentation.
ABSTRACT
Objective To investigate the feasibility and safety of colorectal anastomosis using nickel titanium compression anastomosis ring (CAR).MethodsThe clinical data of 83 patients who received colorectal anastomosis at the First Affiliated Hospital of Fujian Medical University from May to December,2010 were prospectively analyzed.All patients were divided into CAR group (41 patients) and stapler group (42 patients) according to the random number table.The operation time,time to postoperative flatus and bowel movement,duration of hospital stay and the incidence of anastomosis-related complications of the 2 groups were observed.The time of extrusion of the rings and anastomotic healing of the CAR group were recorded.All data were analyzed by the t test or chi-square test.ResultsThe mean operation time of the CAR group and the stapler group were ( 122 ± 25) minutes and (128 ±30)minutes,respectively.The incidences of postoperative anastomotic fistula of the CAR group and the stapler group were 5％ (2/41) and 7％ (3/42),and the anastomotic fistula was cured by operation or conservative treatment.There were no significant differences in the mean operation time,time to postoperative flatus and bowel movement,duration of hospital stay and incidence of anastomotic fistula between the 2 groups (t =1.299,0.756,1.636,0.974,x2 =0.165,P ＞ 0.05 ).The rings were expelled within 9-14 days.The incidences of anastomotic stenosis of the CAR group and stapler group were 0 (0/41) and 2％ (1/42),with no significant difference between the 2 groups (x2 =0.988,P ＞ 0.05).The anastomotic stoma was smooth and well bealed in the CAR group,while nail residues and inflammatory polyp (1 patient) were found at the anastomosis stoma in the stapler group.ConclusionNickel titanium CAR is safe and effective in colorectal anastomosis.