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BACKGROUND: Although laparoscopic colorectal cancer resection is an oncologically safe procedure equivalent to open resection,the effects of conversion of a laparoscopic approach to an open approach remain unclear.This study evaluated the cancer characteristic and oncological outcomes associated with conversion of laparoscopic colorectal resection to open surgery. METHOD: We conducted searches on PubMed, EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Trials. We included the literature published until 2018 that examined the impact of laparoscopic conversion to open colorectal resection. Only randomized control trials and prospective studies were included. Each study was reviewed and the data were extracted. Fixed-effects methods were used to combine data, and 95% confidence intervals (CIs) were used to evaluate the outcomes. RESULTS: Twelve studies with 5427 patients were included. Of these, 4672 patients underwent complete laparoscopic resection with no conversion (LAP group), whereas 755 underwent conversion to an open resection (CONV group). The meta-analysis showedsignificant differences between the LAP group and converted (CONV) group with respect to neoadjuvant therapy (P = .002), location of the rectal cancer (P = .01), and recurrence (P = .01). However, no difference in local recurrence (P = .17) was noted between both groups. CONCLUSION: Conversion of laparoscopic to open colorectal cancer resection is influenced by tumor characteristics. Conversion of laparoscopic surgery for colorectal cancer is associated with a worse oncological outcome.

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Large-scale industrial applications of barrier films and coatings that prevent permeation of degradative gases and moisture call for the development of cost-efficient and ecofriendly polymer nanocomposites. Herein, we report the facile fabrication of latex nanocomposites (LNCs) by incorporating surface-modified graphene oxide (mGO) at various loadings (0.025-1.2 wt %) into a styrene-acrylic latex using water as the processing solvent. LNCs fabricated with mGO exhibited significant reductions (up to 67%) in water vapor sorption, resulting in greater environmental stability when compared to LNCs fabricated with equivalent loading of hydrophilic, unmodified GO. The assembly and coalescence of the exfoliated latex/mGO dispersions during the film formation process produced highly dispersed and well-ordered mGO domains with high aspect ratios, where alignment and overlap of the mGO domains improved with increasing mGO content. The addition of only 0.7 vol % (1.2 wt %) mGO led to an 84% decrease (relative to the neat polymer latex film) in oxygen permeability of the LNC films, an excellent barrier performance attributed to the observed LNC film morphologies. This work enables ecofriendly development of mechanically flexible mGO/LNC films with superior barrier properties for many industrial applications including protective coatings, food packaging, and biomedical products.