Mechanical activation-enhanced metal-organic coordination strategy to fabricate high-performance starch/polyvinyl alcohol films by extrusion blowing.

The production of high-performance starch-based packaging films by extrusion blowing is challenging, ascribed to poor processability of the blend precursors. In this study, a new strategy of mechanical activation (MA)-enhanced metal-organic coordination was proposed to improve the processability of starch (St)/polyvinyl alcohol (PVA) blend precursor, with calcium acetate (CA) as a chelating agent and glycerol as a plasticizer. MA pretreatment activated the hydroxyl groups of starch and PVA for constructing strong metal-organic coordination between CA and St/PVA during reactive extrusion, which effectively enhanced the melt processing properties of the blend precursor, contributing to the fabrication of high-performance St/PVA films by the extrusion-blowing method. The as-prepared St/PVA films exhibited excellent mechanical properties (tensile strength of 34.5 MPa; elongation at break of 271.8 %), water vapor barrier performance (water vapor permeability of 0.704 × 10-12 g·cm-1·s-1·Pa-1), and oxygen barrier performance (oxygen transmission rate of 0.7 cm3/(m2·day·bar)), along with high transmittance and good uniformity. These outstanding characteristics and performances can be attributed to the improved interfacial interaction and compatibility between the two matrix phases. This study uncovers the mechanism of MA-enhanced metal-organic coordination for improving the properties of starch-based films, which provides a convenient and eco-friendly technology for the preparation of high-performance biodegradable films.

Fabrication of a poly(N-isopropylacrylamide)-grafted alginate composite aerogel for efficient treatment of emulsified oily wastewater.

The treatment of emulsion wastewater poses significant challenges. In this study, a novel porous material, namely esterified bagasse/poly(N, N-dimethylacrylamide)/sodium alginate (SBS/PDMAA/Alg) aerogel, was developed for efficient demulsification and oil recovery. By grafting a poly(N-isopropylacrylamide) (PNIPAM) brush onto the SBS/PDMAA/Alg skeleton through free radical polymerization, the resulting aerogel exhibits both surface charge and a molecular brush structure. The aerogel demonstrates remarkable demulsification efficiency for cationic surfactant-stabilized emulsions at various concentrations, achieving a demulsification efficiency of 95.6% even at an oil content of 100 g L-1. Furthermore, the molecular brush structure extends the application range of the aerogel, enabling a demulsification efficiency of 98.3% for anionic and non-ionic surfactant-stabilized emulsions. The interpenetrating polymer network (IPN) structure formed by SBS, PDMAA, and alginate enhances the mechanical stability of the aerogel, enabling a demulsification efficiency of 91.3% even after 20 repeated cycles. The demulsification ability of the composite aerogel is attributed to its surface charge, high interfacial activity, and unique brush-like structure. A demulsification mechanism based on the synergistic effect of surface charge and molecular brush is proposed to elucidate the efficient demulsification process.

Construction and validation of a prognosis signature based on the immune microenvironment in gastric cancer.

Background: Gastric cancer (GC) is an aggressive malignant tumor with a high degree of heterogeneity, and its immune microenvironment is closely associated with tumor growth, development and drug resistance. Therefore, a classification system of gastric cancer based explicitly on the immune microenvironment context might enrich the strategy for gastric cancer prognosis and therapy. Methods: A total of 668 GC patients were collected from TCGA-STAD (n = 350), GSE15459 (n = 192), GSE57303 (n = 70) and GSE34942 (n = 56) datasets. Three immune-related subtypes (immunity-H, -M, and -L) were identified by hierarchical cluster analysis based on the ssGSEA score of 29 immune microenvironment-related gene sets. The immune microenvironment-related prognosis signature (IMPS) was constructed via univariate Cox regression, Lasso-Cox regression and multivariate Cox regression, and nomogram model combining IMPS and clinical variables was further constructed by the "rms" package. RT-PCR was applied to validate the expression of 7 IMPS genes between two human GC cell lines (AGS and MKN45) and one normal gastric epithelial cell line (GES-1). Results: The patients classified as immunity-H subtype exhibited highly expressed immune checkpoint and HLA-related genes, with enriched naïve B cells, M1 macrophages and CD8 T cells. We further constructed and validated a 7-gene (CTLA4, CLDN6, EMB, GPR15, ENTPD2, VWF and AKR1B1) prognosis signature, termed as IMPS. The patients with higher IMPS expression were more likely to be associated with higher pathology grade, more advanced TNM stages, higher T and N stage, and higher ratio of death. In addition, the prediction values of the combined nomogram in predicting 1-year (AUC = 0.750), 3-year (AUC = 0.764) and 5-year (AUC = 0.802) OS was higher than IMPS and individual clinical characteristics. Conclusions: The IMPS is a novel prognosis signature associated with the immune microenvironment and clinical characteristics. The IMPS and the combined nomogram model provide a relatively reliable predictive index for predicting the survival outcomes of gastric cancer.

Facile solid-phase synthesis of starch-fatty acid complexes via mechanical activation for stabilizing curcumin-loaded Pickering emulsions.

Starch-fatty acid complexes used as emulsifiers have caught great attention because of their renewability and excellent emulsifying property, the development of a simple and efficient synthesis method for the fabrication of starch-fatty acid complexes is still greatly challenging. Herein, the rice starch-fatty acid complexes (NRS-FA) were successfully prepared by mechanical activation method using different long chain fatty acids (myristic acid, palmitic acid, and stearic acid) and native rice starch (NRS) as the raw materials. The results showed that the prepared NRS-FA with a V-shaped crystalline structure exhibited a higher digestion resistance than NRS. Moreover, when the chain length of fatty acids increased from 14 to 18 carbons, the contact angle of the complexes was much closer to 90°, and the average particle size was smaller, deriving the better emulsifying property of NRS-FA18 complexes, which were suitable to be used as an emulsifier to stabilize curcumin-loaded Pickering emulsions. The results of storage stability and in vitro digestion showed that the curcumin retention could reach 79.4 % after 28 days of storage and 80.8 % of curcumin was retained in the system after simulated gastric digestion, showing good encapsulation and delivery performance of prepared Pickering emulsions, which attributed to the enhancement of the coverage of particles at the oil-water interface.

First report of zucchini tigre mosaic virus infecting four cucurbit crops in China.

Cucurbits including ridge gourd (Luffa acutangula), Chieh-qua (Benincasa hispida Cogn. var. Chieh-qua How), Trichosanthes anguina, and sponge gourd (L. cylindrica) are important vegetables in most Asian countries. The 90 viruses known to infect cucurbits include 15 species in genus Potyvirus. In October 2020, nine cucurbit samples with leaf distortion, blister and mottle were collected from the same field of Foshan City, Guangdong Province, China. All samples were tested by western blot with potyvirus-specific antibody (Agdia lnc., Elkhart, IN) and RT-PCR with potyvirus degenerate primers Sprimer/M4T (Chen et al. 2001). Seven out of nine samples were positive for potyvirus in both tests, including one ridge gourd, one Chieh-qua, one sponge gourd, two bottle gourd (Lagenaria siceraria) and two T. anguina. All PCR products (~700-bp) were cloned and sequenced. Sequences of seven amplicons (OM522614 to OM522618, OP090158 to OP090159) containing partial nib and cp genes shared 80.3-100% nucleotide (nt) identity among themselves, and 81.2-97.7% nt identity with ZTMV isolates from China (MN267689, LC371337, MK988416). Except for one Chieh-qua sample, papaya ringspot virus (PRSV) was detected in the same samples where ZTMV was found through sequencing of the amplicons mentioned above. The obtained sequences (OM808942 to OM808945, OP090170 to OP090171) were 95.4-100% identical with PRSV isolates from China. Further RT-PCR was conducted with ZTMV-specific primers ZTMVdF/ZTMVdR targeting partial P3 and 6K1 genes, and PRSV-specific primers PRSV3778F/PRSV4630R targeting partial P3, full-length 6K1 and partial CI genes for all nine samples. Consistently, seven samples were positive for ZTMV, among which one Chieh-qua sample was infected with only ZTMV and six samples were co-infected with ZTMV and PRSV. Interspecific recombination event has been reported for ZTMV (Peng et al. 2021), to detect the recombinants, RT-PCR was conducted for all nine samples with primers ZTMV600F/ZTMV2400R covering the interspecies recombination site (Peng et al. 2021). A fragment (~1.8 kb) was amplified from one T. anguina sample and sequenced (OP090172), which had 97.0% nt identity with the reported recombinant ZTMV-KF17 (MK988415). To fulfill Koch's postulates, a Chieh-qua sample detected with ZTMV but not PRSV, was used for mechanical inoculation on Chieh-qua seedlings. Blister and leaf distortion similar to the field symptoms were observed 21 days post-inoculation. ZTMV infection was verified by RT-PCR with primer pairs Sprimer/M4T and ZTMVdF/ZTMVdR, respectively, followed by sequencing. No amplicon was detected with primer pairs PRSV3778F/PRSV4630R and ZTMV600F/ZTMV2400R. To study the incidence of ZTMV and PRSV, 33 samples including T. anguina, ridge gourd and Chieh-qua were collected from three different fields in Foshan City in May 2022, and were tested by RT-PCR with ZTMV and PRSV primers aforementioned. 30.3% (10/33) of the samples were positive for ZTMV, 39.4% (13/33) tested positive for PRSV, and 21.2% (7/33) were co-infected with the two viruses. Amplicons of ZTMV (600 bp) from all positive samples were sequenced (OP090160 to OP090169), and were 84.8-85.5% identical with ZTMV-TW (LC371337). Recombinant of ZTMV was detected in one T. anguina with primers mentioned above and was sequenced (OP090173), which had 96.2% nt identity with ZTMV-KF17. To our knowledge, this is the first report of ZTMV infecting ridge gourd, Chieh-qua, T. anguina and sponge gourd. The results implied that ZTMV had a potential risk to more cucurbit crops in the field.

A Neuropeptide Y/F-like Polypeptide Derived from the Transcriptome of Turbinaria peltata Suppresses LPS-Induced Astrocytic Inflammation.

Neuropeptides are a group of neuronal signaling molecules that regulate physiological and behavioral processes in animals. Here, we used in silico mining to predict the polypeptide composition of available transcriptomic data of Turbinaria peltata. In total, 118 transcripts encoding putative peptide precursors were discovered. One neuropeptide Y/F-like peptide, named TpNPY, was identified and selected for in silico structural, in silico binding, and pharmacological studies. In our study, the anti-inflammation effect of TpNPY was evaluated using an LPS-stimulated C8-D1A astrocyte cell model. Our results demonstrated that TpNPY, at 0.75-3 µM, inhibited LPS-induced NO production and reduced the expression of iNOS in a dose-dependent manner. Furthermore, TpNPY reduced the secretion of proinflammatory cytokines. Additionally, treatment with TpNPY reduced LPS-mediated elevation of ROS production and the intracellular calcium concentration. Further investigation revealed that TpNPY downregulated the IKK/IκB/NF-κB signaling pathway and inhibited expression of the NLRP3 inflammasome. Through molecular docking and using an NPY receptor antagonist, TpNPY was shown to have the ability to interact with the NPY Y1 receptor. On the basis of these findings, we concluded that TpNPY might prevent LPS-induced injury in astrocytes through activation of the NPY-Y1R.

Synthesis of starch-based super absorbent polymer with high agglomeration and wettability for applying in road dust suppression.

Dust pollution is an important factor restricting social development and affecting human health, especially in some developing countries. Herein, mechanical activation-assisted solid phase reaction (MASPR) and conventional liquid phase (LP) method were employed to synthesize different superabsorbent polymers (SAPs), defined as SAP-MA and SAP-LP, respectively. The rheological properties, crystal structure, changes of functional groups, and dust suppression performance of the SAPs prepared by these two methods were compared, and the dust suppression mechanism of SAPs was discussed via the adsorption experiment between dust suppressant and dust particles. The results showed that SAPs were successfully prepared by the two methods. Compared with SAP-LP, SAP-MA with lower molecular weight, higher grafting rate, and better fluidity and water absorption showed excellent suppression performance. This enhancement could be attributed to that the SAP-MA exhibited lower crystallinity and better film-forming ability, anti-evaporation, anti-consolidation, and permeability induced by MA. Furthermore, the effective chemical adsorption between SAPs and dust particles had a stable consolidation effect. This environmentally-friendly method for the preparation of starch-based super absorbent polymer for road dust suppressant may provide new insights for the valorization of cassava starch and large-scale production of dust suppressant.