Evaluation of commercial probiotic lactic cultures against biofilm formation by Cronobacter sakazakii

BACKGROUND/AIMS: Cronobacter sakazakii, an emergent pathogen is considered as a major concern to infants and neonates fed on reconstituted powdered infant milk formula. In conjunction with many other factors, biofilm forming capacity adds to its pathogenic potential. In view of the facts that infants are at highest risk to C. sakazakii infections, and emerging antibiotic resistance among pathogens, it is imperative to evaluate probiotic cultures for their efficacy against C. sakazakii. Therefore, pure probiotic strains were isolated from commercial probiotic products and tested for their antimicrobial and anti-biofilm activities against C. sakazakii. METHODS: A total of 6 probiotic strains were tested for their antibiotic susceptibility followed by antimicrobial activity using cell-free supernatant (CFS) against C. sakazakii. The inhibitory activity of CFS against biofilm formation by C. sakazakii was determined using standard crystal violet assay and microscopic observations. RESULTS: All the probiotic strains were sensitive to ampicillin, tetracycline, vancomycin and carbenicillin whereas most of the strains were resistant to erythromycin and novobiocin. Four of the 6 probiotic derived CFS possessed antimicrobial activity against C. sakazakii at a level of 40 μL. A higher biofilm inhibitory activity (>80%) was observed at initial stages of biofilm formation with weaker activity during longer incubation upto 48 hours (50%–60%). CONCLUSIONS: The study indicated the efficacy of isolated commercial probiotics strains as potential inhibitor of biofilm formation by C. sakazakii and could be further explored for novel bioactive molecules to limit the emerging infections of C. sakazakii.

Natural Orifice Specimen Extraction With Single Stapling Colorectal Anastomosis for Laparoscopic Anterior Resection: Feasibility, Outcomes, and Technical Considerations.

BACKGROUND: Double and triple stapling techniques to close the rectal stump in laparoscopic anterior resection are fraught with technical drawbacks that could possibly be avoided with the use of the single stapling technique. However, little is known of its safety in laparoscopic surgery or outcomes when combined with natural orifice specimen extraction. OBJECTIVE: This study aims to analyze the feasibility and the operative and immediate postoperative outcomes of single-stapled anastomosis and natural orifice specimen extraction with conventional techniques. It intends to evaluate technical variations related to colon, mesentery, and pelvic anatomy characteristics. DESIGN AND PATIENTS: A consecutive series of 188 patients underwent elective surgery for benign or malignant lesions between 10 and 40 cm from the anal verge, 5 cm or less in diameter on radiological examination, stage T1 to T3, Nx, M0, with 2 different methods of rectal stump closure (pursestring vs linear-stapled closure) associated with single or double stapling and per anus vs conventional specimen extraction. SETTING: This study was conducted at China Medical University Hospital, Taiwan, a tertiary referral center, between January 2012 and April 2015. MAIN OUTCOME MEASURES: The main outcomes measured are feasibility and operative and immediate postoperative outcomes. RESULTS: Single-stapled resection with natural orifice specimen extraction was feasible in 94% patients with an 11% perioperative morbidity rate. The patients required statistically significantly less analgesia, had earlier return of bowel movements, and shorter hospital stay, whereas there was no statistically significant difference in the overall readmission rate and overall morbidity, including anastomotic leakage. LIMITATIONS: This was a single-center, retrospective case-matched study. CONCLUSION: Anatomic variations (short colon and short mesentery) can be managed adequately with intracorporeal anvil head fixation. The single stapling technique is feasible and as safe as conventional double stapling techniques, although it is technically more demanding. The transanal endoscopic operation platform can be useful when the rectal stump is long.