"Five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in laparoscopic pancreaticoduodenectomy.

BACKGROUND: Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment, the feasibility and safety of this approach for laparoscopic pancreaticoduodenectomy (LPD) require further clinical evaluation and investigation. AIM: To explore the application value of the "five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients. METHODS: A total of 52 patients who underwent LPD via the "five steps four quadrants" modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively. The patients' body mass index (BMI), preoperative laboratory indices, intraoperative variables and postoperative complications were recorded. The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed. RESULTS: Among the 52 patients, 36 were males and 16 were females, and the average age was 62.2 ± 11.0 years. There were 26 patients with pancreatic head cancer, 16 patients with periampullary cancer, and 10 patients with distal bile duct cancer. The BMI was 22.3 ± 3.3 kg/m², and the median total bilirubin (TBIL) concentration was 57.7 (16.0-155.7) µmol/L. All patients successfully underwent the "five steps four quadrants" modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage. Correlation analysis revealed significant associations between preoperative BMI (r = 0.3581, P = 0.0091), TBIL level (r = 0.2988, P = 0.0341), prothrombin time (r = 0.3018, P = 0.0297) and lymph node dissection time. Moreover, dissection time was significantly correlated with intraoperative blood loss (r = 0.7744, P < 0.0001). Further stratified analysis demonstrated that patients with a preoperative BMI ≥ 21.9 kg/m² and a TIBL concentration ≥ 57.7 µmol/L had significantly longer lymph node dissection times (both P < 0.05). CONCLUSION: The "five steps four quadrants" modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD. This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve; thus, it is worthy of further clinical promotion and application.

Sensitive Organic Vapor Sensors Based on Flexible Porous Conductive Composites with Multilevel Pores and Thin, Rough, Hollow-Wall Structure.

Advanced organic vapor sensors that simultaneously have high sensitivity, fast response, and good reproducibility are required. Herein, flexible, robust, and conductive vapor-grown carbon fibers (VGCFs)-filled polydimethylsiloxane (PDMS) porous composites (VGCFs/PDMS sponge (CPS)) with multilevel pores and thin, rough, and hollows wall were prepared based on the sacrificial template method and a simple dip-spin-coating process. The optimized material showed outstanding mechanical elasticity and durability, good electrical conductivity and hydrophobicity, as well as excellent acid and alkali tolerance. Additionally, CPS exhibited good reproducible sensing behavior, with a high sensitivity of ~1.5 × 105 s-1 for both static and flowing organic vapor, which was not affected in cases such as 20% squeezing deformation or environment humidity distraction (20~60% RH). Interestingly, both the reproducibility and sensitivity of CPS were better than those of film-shaped VGCFs/PDMS (CP), which has a thickness of two hundred microns. Therefore, the contradiction between the reproducibility and high sensitivity was well-solved here. The above excellent performance could be ascribed to the unique porous structures and the rough, thin, hollow wall of CPS, providing various gas channels and large contact areas for organic vapor penetration and diffusion. This work paves a new way for developing advanced vapor sensors by optimizing and tailoring the pore structure.

Green and Rapid Preparation of Fluorosilicone Rubber Foam Materials with Tunable Chemical Resistance for Efficient Oil-Water Separation.

Polydimethylsiloxane (PDMS) foam materials with lightweight, excellent oil resistance and mechanical flexibility are highly needed for various practical applications in aerospace, transportation, and oil/water separation. However, traditional PDMS foam materials usually present poor chemical resistance and easily swell in various solvents, which greatly limits their potential application. Herein, novel fluorosilicone rubber foam (FSiRF) materials with different contents of trifluoropropyl lateral groups were designed and fabricated by a green (no solvents used) and rapid (<10 min foaming process) foaming/crosslinking approach at ambient temperature. Typically, vinyl-terminated poly(dimethyl-co-methyltrifluoropropyl) siloxanes with different fluorine contents of 0−50 mol% were obtained through ring-opening polymerization to effectively adjust the chemical resistance of the FSiRFs. Notably, the optimized FSiRF samples exhibit lightweight (~0.25 g/cm−3), excellent hydrophobicity/oleophilicity (WCA > 120°), reliable mechanical flexibility (complete recovery ability after stretching of 130% strain or compressing of >60%), and improved chemical resistance and structural stability in various solvents, making them promising candidates for efficient and continuous oil−water separation. This work provides an innovative concept to design and prepare advanced fluorosilicone rubber foam materials with excellent chemical resistance for potential oil−water separation application.

Ultrafast Flame-Induced Pyrolysis of Poly(dimethylsiloxane) Foam Materials toward Exceptional Superhydrophobic Surfaces and Reliable Mechanical Robustness.

Superhydrophobic surfaces are imperative in flexible polymer foams for diverse applications; however, traditional surface coatings on soft skeletons are often fragile and can hardly endure severe deformation, making them unstable and highly susceptible to cyclic loadings. Therefore, it remains a great challenge to balance their mutual exclusiveness of mechanical robustness and surface water repellency on flexible substrates. Herein, we describe how robust superhydrophobic surfaces on soft poly(dimethylsiloxane) (PDMS) foams can be achieved using an extremely simple, ultrafast, and environmentally friendly flame scanning strategy. The ultrafast flame treatment (1-3 s) of PDMS foams produces microwavy and nanosilica rough structures bonded on the soft skeletons, forming robust superhydrophobic surfaces (i.e., water contact angles (WCAs) > 155° and water sliding angles (WSAs) < 5°). The rough surface can be effectively tailored by simply altering the flame scanning speed (2.5-15.0 cm/s) to adjust the thermal pyrolysis of the PDMS molecules. The optimized surfaces display reliable mechanical robustness and excellent water repellency even after 100 cycles of compression of 60% strain, stretching of 100% strain, and bending of 90° and hostile environmental conditions (including acid/salt/alkali conditions, high/low temperatures, UV aging, and harsh cyclic abrasion). Moreover, such flame-induced superhydrophobic surfaces are easily peeled off from ice and can be healable even after severe abrasion cycles. Clearly, the flame scanning strategy provides a facile and versatile approach for fabricating mechanically robust and surface superhydrophobic PDMS foam materials for applications in complex conditions.

[A randomized controlled trial of postoperative artificial nutrition in malnourished patients with gastrointestinal cancer].

OBJECTIVE: To investigate the potential benefits of postoperative nutrition in malnourished patients with gastrointestinal cancer. METHODS: A total of 646 malnourished patients with gastrointestinal cancer defined by the subjective global assessment (SGA) were randomly divided into parenteral nutrition group (n=215), enteral nutrition group (n=215) and conventional group (n=216). Two nutritional regimens were designed to be isocaloric 125.5 kJ(30 kcal).kg(-1).d(-1) and isonitrogenous 0.25 g.kg(-1).d(-1) for 7 postoperative days. Conventional group did not receive artificial nutrition before and after surgery. Postoperative complications, mortality and postoperative length of hospital stay were compared. RESULTS: All baseline and surgical characteristics were comparable among 3 groups. Overall postoperative mortality was 1.5%, and no difference was observed among 3 groups. Postoperative complications occurred in 61(28.4%) patients in enteral nutrition group, 72(33.5%) in parenteral nutrition group, and 97 (44.9%) in conventional group (P=0.000 vs enteral nutrition group; P=0.001 vs parenteral nutrition group). Postoperative length of hospital stay was (9.8+/-3.4) d in enteral nutrition group, (11.2+/-5.0) d in parenteral nutrition group, and (14.5+/-7.1) d in conventional group (P=0.001 vs enteral nutrition group; P=0.003 vs parenteral nutrition group). CONCLUSIONS: Postoperative artificial nutrition support is beneficial to the malnourished patients with gastrointestinal cancer, which improves postoperative outcome. Early enteral nutrition significantly reduces the infectious complication rate and length of postoperative hospital stay as compared with parenteral nutrition.