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The discovery of natural adhesion phenomena and mechanisms has advanced the development of a new generation of tissue adhesives in recent decades. In this study, we develop a natural biological adhesive from snail mucus gel, which consists a network of positively charged protein and polyanionic glycosaminoglycan. The malleable bulk adhesive matrix can adhere to wet tissue through multiple interactions. The biomaterial exhibits excellent haemostatic activity, biocompatibility and biodegradability, and it is effective in accelerating the healing of full-thickness skin wounds in both normal and diabetic male rats. Further mechanistic study shows it effectively promotes the polarization of macrophages towards the anti-inflammatory phenotype, alleviates inflammation in chronic wounds, and significantly improves epithelial regeneration and angiogenesis. Its abundant heparin-like glycosaminoglycan component is the main active ingredient. These findings provide theoretical and material insights into bio-inspired tissue adhesives and bioengineered scaffold designs. Natural adhesives have received a lot of attention recently. Here, the authors develop a natural biological adhesive from snail mucus that can adhere to wet tissue and be used to accelerate healing of skin wounds.

Hydraulic fracturing, as a critical technology for reservoir stimulation, has functioned as a central stimulation technique in the large-scale development of shale gas and coalbed methane. During hydraulic fracturing operations, the movement and distribution of proppants within fractures serve as the key determinant of both fracture conductivity created by fracturing and long-term sustained production performance. Meanwhile, the settling and packing mechanisms of proppants greatly affects proppant transportation efficiency and distribution within fractures, which in turn determines the level of oil and gas production. However, current research on settling and packing mechanisms of proppants has primarily focused on spherical proppants, while some aspects of the non-spherical shaped proppants with different shapes and structures have not yet been fully considered. In this study, 3D printing technology was utilized to fabricate various non-spherical proppants, including cube, rhombohedron, tetrahedron, cuboid, and cylinder shapes. Compared to spherical proppants, these non-spherical counterparts were examined in terms of their settling, transport, and packing mechanisms using visualized proppant settling and transport setup. The result show that proppants with irregular shapes, such as rhombohedrons and tetrahedrons, experienced greater turbulent effects in the fluid, while proppants with regular shapes, such as cuboids, cubes, cylinders, and spheres, generated much less turbulence. For instance, under a low viscosity of 1 mPa·s, the settling velocity of spherical proppants was measured at 0.086 m/s, significantly higher than the 0.046 m/s for rhombohedron and 0.052 m/s for tetrahedron proppants. More importantly, the angle variation during the settlement process was much larger for the irregular-shaped proppants than for the regular ones. Moreover, the results also indicate that under low-viscosity conditions (< 3 mPa·s), non-spherical shape has a more significant effect on settling velocity. However, this effect becomes less apparent when the viscosity increases to the range of 6–9 mPa·s. Porosity measurements further revealed that rhombohedron and tetrahedron proppants achieved higher porosities (approximately 40–45%) compared to spheres and cubes (~ 35%), suggesting potential for enhanced fracture permeability. Finally, six new mathematical models were developed to predict the terminal settling velocity of different types of non-spherical shape proppants. The study of non-spherical proppants might provide a new idea for proppants application with new structures in the future.

Fucoidan, a sulfated glycan derived from brown algae, has garnered significant attention for its anticoagulant properties. However, the structural complexity and heterogeneity of naturally extracted fucoidan have hindered a comprehensive understanding of its structure-activity relationship, limiting the development of fucoidan-based anticoagulant drugs. To address this challenge, we synthesize a diverse library of 58 distinct fucoidans with multiple contiguous 1,2- cis glycosidic bonds, ranging from disaccharides to dodecasaccharides, using a highly efficient preactivation-based one-pot glycosylation strategy. This library includes compounds with various sulfation patterns (2,3- O - di- , 3,4- O - di- , and 2,3,4- O - tri -sulfation) encompassing nearly all possible fucoidan structures. In vitro anticoagulant assays demonstrate that both molecular size and degree of sulfation play crucial roles in anticoagulant potency. Notably, compounds 29 , 30 , 37 , and 58 significantly prolong human plasma activated partial thromboplastin time (APTT), comparable to the effect of enoxaparin, without affecting prothrombin time (PT) or thrombin time (TT). This selective inhibition of the intrinsic coagulation pathway suggests a reduced risk of bleeding, highlighting the therapeutic potential of these fucoidans as safer anticoagulant agents. Fucoidan is a sulfated glycan with anticoagulant properties, but its structural complexity and heterogeneity hinders understanding of its structure-activity relationship. Here, the authors synthesize a diverse library of 58 distinct fucoidans with multiple contiguous 1,2- cis glycosidic bonds and various sulfation patterns, and investigate their anticoagulant activity.

Selective inhibition of the intrinsic coagulation pathway is a promising strategy for developing safer anticoagulants that do not cause serious bleeding. Intrinsic tenase, the final and rate-limiting enzyme complex in the intrinsic coagulation pathway, is an attractive but less explored target for anticoagulants due to the lack of a pure selective inhibitor. Fucosylated glycosaminoglycan (FG), which has a distinct but complicated and ill-defined structure, is a potent natural anticoagulant with nonselective and adverse activities. Herein we present a range of oligosaccharides prepared via the deacetylation–deaminative cleavage of FG. Analysis of these purified oligosaccharides reveals the precise structure of FG. Among these fragments, nonasaccharide is the minimum fragment that retains the potent selective inhibition of the intrinsic tenase while avoiding the adverse effects of native FG. In vivo, the nonasaccharide shows 97% inhibition of venous thrombus at a dose of 10 mg/kg in rats and has no obvious bleeding risk. This nonasaccharide may therefore serve as a novel promising anticoagulant.

Background Single-incision plus one-port laparoscopic surgery (SILS + 1) has been demonstrated to be minimally invasive while possessing better cosmesis and less pain compared with conventional laparoscopic surgery (CLS). However, SILS + 1 as an alternative to CLS for colorectal cancer is still controversial. Methods A total of 1071 patients who underwent curative laparoscopic surgery for colon cancer between 2015 and 2018 were included. Of these patients, 258 SILS + 1 cases and 516 CLS cases were analyzed using propensity score matching. The baseline characteristics, surgical outcomes, pathologic findings and recovery course, morbidity and mortality within postoperative 30 days and 3-year disease-free and overall survival were compared. Results Baseline characteristics were balanced between the groups. The mean operating time was significantly shorter in SILS + 1 group, with less estimated blood loss. Tumor size, tumor differentiation, number of harvested lymph nodes, resection margin and pathologic T, N, TNM stage was similar between the groups. There was no significant difference in overall perioperative complications. Uni- and multivariate analyses revealed that SILS + 1 was not a risk factor for complications. Postoperatively, SILS + 1 group showed faster recovery than CLS group in terms of ambulation, bowel function, oral intake and discharge. The 3-year disease-free survival rates of SILS + 1 and CLS groups were 90.1% and 87.3%(p = 0.59), respectively and the 3-year overall survival rates were 93.3% vs. 89.8%(p = 0.172). Discussion Our study revealed that SILS + 1 is safe, feasible, oncologically efficient, and may be considered as a surgical option for selected patients with colorectal cancer.

Background Though our previous study has demonstrated that the single-incision plus one-port laparoscopic surgery (SILS + 1) is safe and feasible for sigmoid colon and upper rectal cancer and has better short-term outcomes compared with conventional laparoscopic surgery (CLS), the long-term outcomes of SILS + 1 remains uncertain and are needed to evaluated by an RCT. Methods Patients with clinical stage T1-4aN0-2M0 rectosigmoid cancer were enrolled. The participants were randomly assigned to either SILS + 1 (n = 99) or CLS (n = 99). The 3-year DFS, 5-year OS, and recurrence patterns were analyzed. Results Between April 2014 and July 2016, 198 patients were randomly assigned to either the SILS + 1 group (n = 99) or CLS group (n = 99). The median follow-up in the SILS + 1 group was 64.0 months and in CLS group was 65.0 months. The 3-year DFS was 87.8% (95% CI, 81.6–94.8%) in SILS + 1 group and 86.9% (95% CI, 81.3–94.5%) in CLS group (hazard ratio: 1.09 (95% CI, 0.48–2.47; P = 0.84)). The 5-year OS was 86.7% (95% CI,79.6–93.8%) in the SILS + 1 group and 80.5% (95% CI,72.5–88.5%) in the CLS group (hazard ratio: 1.53 (95% CI, 0.74–3.18; P = 0.25)). There were no significant differences in the recurrence patterns between the two groups. Conclusions We found no significant difference in 3-year DFS and 5-year OS of patients with sigmoid colon and upper rectal cancer treated with SILS + 1 vs. CLS. SILS + 1 is noninferior to CLS when performed by expert surgeons. Trial registration ClinicalTrials.gov: NCT02117557 (registered on 21/04/2014).

In order to search for sulfated polysaccharides in different invertebrate connective tissues and to examine their biological activities, we have isolated three types of polysaccharides from the body wall of the three sea cucumbers Holothuria edulis, Apostichopus japonicas and Holothuria nobilis. The physicochemical properties and anticoagulant activities of these polysaccharides were examined and compared. The chemical composition analysis and nuclear magnetic resonance (NMR) analysis indicate that two types of polysaccharides, sulfated fucan and fucosylated chondroitin sulfate (FuCS), were found in all of the three species and in addition a neutral glycan was observed in H. edulis. The neutral α-glucan was firstly obtained from sea cucumber. The same type of polysaccharides from different species of sea cucumbers have similar physicochemical properties and anticoagulant activities, but those of different types of glycans are significantly different, possibly due to their different monosaccharide compositions, electric charges and average molecular weights. The FuCSs have stronger anticoagulant activities than the sulfated fucans, although the molecular sizes of the FuCSs are lower than those of the sulfated fucans, whereas the neutral glucan has no activity, as expected from the absence of sulfate. Thus, anticoagulant activities of the different type of polysaccharides are likely to relate to monosaccharide composition and sulfate content. Preliminary analysis suggests that the sulfation patterns of the FuCSs may result in the difference in anticoagulant activities. Our data could help elucidate the structure-activity relationship of the sea cucumber polysaccharides.

The plasma contact system sits atop the intrinsic coagulation cascade and plasma kallikrein–kinin pathway, and in vivo its activation contributes, respectively, to coagulation and inflammation mainly via two downstream pathways. This system has been widely investigated, its activation mechanisms by negatively charged surfaces and the interactions within its components, factor XII, prekallikrein and high molecular weight kininogen are well understood at the biochemical level. However, as most of the activators that have been discovered by in vitro experiments are exogenous, the physiological activators and roles of the contact system have remained unclear and controversial. In the last two decades, several physiological activators have been identified, and a better understanding of its roles and its connection with other signaling pathways has been obtained from in vivo studies. In this article, we present an overview of the contact pathway with a focus on the activation mechanisms, natural stimuli, possible physiological roles, potential risks of its excessive activation, remaining questions and future prospects.

Bacillus Calmette-Guérin polysaccharide and nucleic acid (BCG-PSN), extracted from Mycobacterium bovis, is an immunoregulatory medicine commonly used in clinic. However, the structural characteristics and potential pharmacological efficacy of the polysaccharides from BCG-PSN remain unclear. Herein, two polysaccharides (BCG-1 and BCG-2) were purified and their structures were characterized. Monosaccharide composition analysis combined with methylation analysis and NMR data indicated that BCG-1 and BCG-2 were an α-D-(1→4)-mannan with (1→2)-linked branches, and an α-D-(1→4)-glucan with (1→6)-linked branches, respectively. Herein, the mannan from BCG-PSN was first reported. Bioactivity assays showed that BCG-1 and BCG-2 dose-dependently and potently increased the production of inflammatory mediators (NO, TNF-α, IL-6, IL-1β, and IL-10), as well as their mRNA expressions in RAW264.7 cells; both have similar or stronger effects compared with BCG-PSN injection. These data suggest that BCG-1 and BCG-2 are very likely the active ingredients of BCG-PSN.

Functional wetting surfaces have excellent prospects in applications including self-cleaning, anti-fog, anti-icing, corrosion resistance, droplet control, and friction power generation. Laser micromachining technology is an advanced method for preparing such functional surfaces with high efficiency and quality. To fully exploit the potential of laser micromachining and the related hybrid methods, a wide spectrum of knowledge is needed. The present review systematically discusses the process capabilities and research developments of laser micromachining and its hybrid methods considering the research both in basic and practical fields. This paper outlines the relevant literature, summarizes the characteristics of functional wetting surfaces and also the basic scientific requirements for laser micromachining technology. Finally, the challenges and potential applications of superhydrophobic and superoleophobic surface are briefly discussed. This review fills the gap in the research literature by presenting an extended literature source with a wide coverage of recent developments.