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The article discusses the findings of a study which determined the bioactivity of ascophyllan on splenic natural killer (NK) cells and RAW264.7 cells. It notes that the effects of ascophyllan were tested in vivo for NK cells, while it was in vitro cytotoxic analysis was done for the mouse macrophage RAW264.7 cells. The experiment confirmed ascophyllan's immunopotentiating characteristic through inducement of high nitric oxide (NO) levels in macrophages.

Genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR) have been suggested as being associated with cerebral palsy (CP) but the evidence is uncertain. The purpose of this study was to investigate whether MTHFR gene polymorphisms contribute to the development of CP in Chinese infants. For this study, 169 health controls and 159 infants with CP including 43 cases also suffering from mental retardation (MR) were recruited. Genomic DNA was prepared from venous blood and all five single nucleotide polymorphisms in MTHFR (rs4846049, rs1476413, rs1801131, rs1801133 and rs9651118) were genotyped using TaqMan technology. There were no significant differences in allele or genotype frequencies between the CP patients and controls at any of the five genetic polymorphisms. Subgroup analysis found statistically significant difference in allele and genotype frequencies between cases with both CP and MR (CP + MR) compared with both CP-only cases and controls at rs4846049, rs1476413 and rs1801131. The frequencies of the T alleles of rs4846049, rs1476413 and the G allele of rs1801131 were greater in the CP + MR patients than in the CP-only patients and controls. This study provides the first evidence pointing to a MTHFR gene polymorphism as a potential risk factor for CP combined with MR. [ABSTRACT FROM AUTHOR]

AbstractAstaxanthin, a ketone carotenoid known for its high antioxidant activity, holds significant potential for application in nutraceuticals, aquaculture, and cosmetics. The increasing market demand necessitates a higher production of astaxanthin using Phaffia rhodozyma. Despite extensive research efforts focused on optimizing fermentation conditions, employing mutagenesis treatments, and utilizing genetic engineering technologies to enhance astaxanthin yield in P. rhodozyma, progress in this area remains limited. This review provides a comprehensive summary of the current understanding of rough metabolic pathways, regulatory mechanisms, and preliminary strategies for enhancing astaxanthin yield. However, further investigation is required to fully comprehend the intricate and essential metabolic regulation mechanism underlying astaxanthin synthesis. Specifically, the specific functions of key genes, such as crtYB, crtS, and crtI, need to be explored in detail. Additionally, a thorough understanding of the action mechanism of bifunctional enzymes and alternative splicing products is imperative. Lastly, the regulation of metabolic flux must be thoroughly investigated to reveal the complete pathway of astaxanthin synthesis. To obtain an in-depth mechanism and improve the yield of astaxanthin, this review proposes some frontier methods, including: omics, genome editing, protein structure-activity analysis, and synthetic biology. Moreover, it further elucidates the feasibility of new strategies using these advanced methods in various effectively combined ways to resolve these problems mentioned above. This review provides theory and method for studying the metabolic pathway of astaxanthin in P. rhodozyma and the industrial improvement of astaxanthin, and provides new insights into the flexible combined use of multiple modern advanced biotechnologies. [ABSTRACT FROM AUTHOR]

Due to the heavy reliance on computers and networks, security issues have become a major concern for individuals, companies, and nations. Traditional security measures such as personal identification numbers, tokens, or passwords only provide limited protection. With the development of intelligent keyboard (IKB), this paper proposes a deep‐learning‐based keystroke dynamics identification method for increased security. The IKB is a kind of self‐powered, nonmechanical‐punching keyboard, which converts mechanical stimuli applied to the keyboard into local electronic signals. Multilayer deep belief network (DBN) is established to mine the useful information from raw electronic signals and output the keystroke dynamics identification result. The contributions include development of a novel solution that does not rely on manual feature extraction, and provides promising recognition accuracy on large amount of typing samples. One significant advantage of the proposed method is that it extracts features adaptively from the raw current signals and automatically recognizes the typing pattern, which simplifies the design of verification and identification system. The experimental results on 104 typing samples demonstrate the effectiveness of the proposed method. The proposed method has extensive applications in keyboard‐based information security. A novel keystroke dynamics identification method is developed for intelligent keyboard using deep learning technologies. Experiment results on 104 typing datasets show that the proposed method has high identification accuracy, stable and reliable performance. [ABSTRACT FROM AUTHOR]

The GH78 α-L-rhamnosidase from Aspergillus tubingensis (AT-Rha) was proved to be a new clade of Aspergillus α-L-rhamnosidases in the previous study. A putative α-L-rhamnosidase from A. kawachii IFO 4308 (AK-Rha) has 92 % identity in amino acid sequence with AT-Rha. In this study, AK-Rha was expressed in P. pastoris and characterized. Similar to AT-rRha, the recombinant AK-Rha (AK-rRha) showed a narrow substrate specificity to naringin. Interestingly, the enzyme activity of AK-rRha was 0.816 U/mg toward naringin, significantly lower than 125.142 U/mg of AT-rRha. Their large differences in catalytic efficiency was mainly due to their differences in k cat values between AK-rRha (0.67 s−1) and AT-rRha (4.89 × 104 s−1). The molecular dynamics simulation exhibited that the overall conformation of AK-Rha was rigid and that of AT-Rha was flexible; the Loop Y-L located above the catalytic domain formed different steric hindrances to naringin, and interacted with the flavonoid matrices at different strengths. The polar solvation energy analysis implied that the glycosidic bond was more easily hydrolysed in AT-Rha. The comparative study verified that the main feature of AK-Rha and AT-Rha represented Aspergillus α-L-rhamnosidase was the narrow substrate specificity toward naringin, and provided an insight of the relationships between their catalytic abilities and structures. • A putative α-L-rhamnosidase AK-Rha has 92 % identity with AT-Rha. • AK-rRha enzyme activity was 0.65 % of AT-rRha enzyme activity. • k cat value of AK-rRha was 3 orders of magnitude lower than AT-rRha. • Overall and local conformation flexibility was essential to high enzyme activity. • Steric hindrance effect of Loop Y-L was closely related to enzyme activity. [ABSTRACT FROM AUTHOR]

There has been ongoing interest in improving the efficiency of glycoside hydrolase for synthesizing glycoside compounds through protein engineering, given the potential applications of glycoside compounds. In this study, a strategy of modifying the substrate access tunnel was proposed to enhance the efficiency of reverse hydrolysis catalyzed by Aspergillus niger α-L-rhamnosidase. Analysis of the tunnel dynamics identified Tyr299 as a key modifiable residue in the substrate access tunnel. The location of Tyr299 was near the enzyme surface and at the outermost end of the substrate access tunnel, suggested its role in substrate recognition and throughput. Based on the properties of side chains, six mutants were designed and expressed by Pichia pastoris. Compared to WT, the reverse hydrolysis efficiencies of mutants Y299P and Y299W were increased by 21.3 % and 11.1 %, respectively. The calculation results of binding free energy showed that the binding free energy was inversely proportional to the reverse hydrolysis efficiency. Further, when binding free energy levels were comparable, the mutants with shorter side chains displayed a higher reverse hydrolysis efficiency. These results proved that substrate access tunnel modification was an effective method to improve the reverse hydrolysis efficacy of α-L-rhamnosidase and also provided new insights for modifying other glycoside hydrolases. • Enhancing reverse hydrolysis efficiency of α-L-rhamnosidase by altering specific site in the substrate tunnel. • The reverse hydrolysis efficiencies of Y299P and Y299W were raised by 21.3 % and 11.1 %, respectively, compared with the WT. • Low binding free energy and short side chain of the mutants contributed to the efficiency of the reverse hydrolysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • CRTS (4-ketolase/3-hydroxylase) was in dicyclic pathway of astaxanthin biosynthesis. • CRTYB (lycopene beta-cyclase) played a role in dicyclic and monocyclic pathway. • CRTS and CRTYB were possible rate-limiting enzymes of carotenoids biosynthesis. Phaffia rhodozyma is a potential industrial source of natural astaxanthin. Dicyclic and monocyclic pathways of carotenoid synthesis are important nodes in Phaffia rhodozyma , but the relationship between the two pathways and astaxanthin production remains unclear. Eight genes related to dicyclic and monocyclic pathways in three different strains of P. rhodozyma were analysed, and the relationship between expression and astaxanthin biosynthesis was explored. Among these genes, CRTS genes (R = 0.69, P < 0.05) and CRTYB (R = 0.75, P < 0.05) showed the closest correlations with carotenoid and astaxanthin biosynthesis, respectively. To further study these relationships in detail, the CRTYB and CRTS genes were knocked out by homologous recombination. After CRTYB knockout, astaxanthin was decreased to an undetectable level. This result suggested that CRTYB plays a role in dicyclic and monocyclic pathways. Meanwhile, the CRTS gene was in the dicyclic pathway of astaxanthin biosynthesis, and its knockout promoted the monocyclic pathway and resulted in a 25 % increase in astaxanthin production at 120 h. The possible rate-limiting enzymes were the enzymes encoding CRTS and CRTYB by regression analysis. Knockout of the CRTS and CRTYB genes was helpful in understanding the synthetic pathway of astaxanthin and significant to the industrial application of astaxanthin production. [ABSTRACT FROM AUTHOR]

The bacterium Microbulbifer sp. ALW1 was previously characterized with the capability to break down the cell wall of brown algae into fine pieces. The biological functions of strain ALW1 were yet to be elucidated. In this study, a gene, namely MaCel5A, was isolated from the ALW1 strain genome, encoding an endo-β-1,4-glucanase. MaCel5A was phylogenetically categorized under the glycoside hydrolase family GH5, with the highest identity to a putative cellulase of Microbulbifer thermotolerans. The recombinant MaCel5A protein purified from heterologous expression in E. coli exhibited maximum activity at 50 °C and pH 6.0, respectively, and functioned selectively toward carboxymethyl cellulose and barley β-glucan. Recombinant MaCel5A demonstrated considerable tolerance to the exposure to high temperature up to 80 °C for 30 min retaining 49% residual activity. In addition, MaCel5A showed moderate stability against pH 5.0–11.0 and strong stability in the presence of nonionic surfactant. MaCel5A exhibited strong halo-stability and halotolerance. The activity of the enzyme increased about tenfold at 0.5 M NaCl, and about fivefold even at 4.0 M NaCl compared to the enzyme activity without the addition of salt. The two conserved glutamic acid residues in MaCel5A featured the typical catalytic acid/base and nucleophile machinery of glycoside hydrolases. These characteristics highlight the industrial application potential of MaCel5A. [ABSTRACT FROM AUTHOR]

• P. haitanensis polysaccharides (PHP) were extracted by ultra-high pressure (UHP). • UHP increased total sugar, uronic acid, and 3,6-anhydro-ʟ-galactose contents of PHP. • UHP resulted in a more rough and porous structure for PHP. • UHP especially 500–600 MPa increased antioxidant and hypolipidemic abilities of PHP. Porphyra haitanensis polysaccharides (PHPs) have potential antioxidant and hypolipidemic activities, but still need improvement. Therefore, ultra-high pressure (UHP) assisted extraction was applied to modify the structure, antioxidant, and hypolipidemic activities of PHPs. UHP assisted extraction increased the total sugar, uronic acid, and 3,6-anhydro-ʟ-galactose contents of PHP, which increased by 15.85 %–16.12 %, 18.95 %–24.32 %, 20.54 %–23.66 % with 500–600 MPa UHP, respectively. Meanwhile, UHP modified PHP became more rough and porous than native PHP. Besides, UHP assisted extracted PHP showed better in vitro antioxidant and hypolipidemic abilities. Especially, 500–600 MPa UHP increased 72.43 %–86.42 % 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacities, 12.32 %–12.82 % pancreatic lipase inhibitory ability, and 14.93 %–15.23 % glycocholate binding abilities of PHP (p < 0.05). Moreover, UHP assisted extracted PHP greatly decreased the lipid droplet and triglyceride contents of 3T3-L1 adipocytes (p < 0.05). Our findings can provide the theoretical basis for the high value utilization of Porphyra haitanensis and its polysaccharides with UHP modification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hypoglycaemic and antioxidant activities of PPE during digestion were detected. • 143 phenolic metabolites were identified based on widely targeted metabolomics. • The hypoglycaemic activity of P. haitanensis was strongest at the fourth harvest. • In vitro digestion processes promoted the hypoglycaemic activity of PPE. • Apigenin and genistein were strongly correlated with the hypoglycaemic activity. The hypoglycemic effect of Porphyra is well known. Based on in vitro digestion and metabolomics, the bioaccessibility, antidiabetic activity and phenolic conversion of P. haitanensis were investigated at different harvests. Total polyphenol content (TPC), α -glucosidase inhibition and oxygen radical absorbance capacity (ORAC) increased with harvesting and digestion stages, reaching maximum at the fourth harvest. TPC and α -glucosidase inhibition after digestion reached 130–150 mg/g and 50–90 %, ORAC was 8.7–13.5 times higher than the undigestion. However, bioaccessibility in the first and second harvests was 10–80 % higher than other harvests. The phenolic content in the fourth harvest was up-regulated to 2–30 times than the first and mostly were citrus flavonoids. Redundancy analysis indicated significant correlation between phenolic metabolites and bioactivities in different harvests of P. haitanensis during digestion, with the strongest correlation coefficients were apigenin and genistein. This study provides reference for the application of P. haitanensis in treating type 2 diabetes. [ABSTRACT FROM AUTHOR]

In this study, the antimicrobial activity on Escherichia coli (E. coli) of a polysaccharide (BFP) prepared from Bangia fusco-purpurea with the underlying mechanism was investigated. The results showed that BFP could against the growth of E. coli in a concentration-dependent manner. The inhibitory effect of BFP on E. coli might be through disrupting the morphology, increasing the intracellular reactive oxygen species levels, and decreasing the Ca2+-Mg2+-ATPase activity in E. coli. Furthermore, BFP significantly reduced the biofilm formation in E. coli by down-regulating the critical biofilm-related genes, including flhD , flhC , fliM , csgA , and csgD , especially fliM , and weakened the bacteria's infection and pathogenic potentials. Notably, the metabolomic analysis demonstrated that BFP performed antimicrobial activity mainly by up-regulating the sphingosine and phospholipids metabolites, down-regulating the amino acid metabolites, and the two-component system in E. coli. The findings advance the understanding on the underlying mechanisms of red seaweed polysaccharide BFP against E. coli , and further provide the scientific basis for developing BFP as a natural antimicrobial agent applied in food additives or pharmaceutical ingredients. • B. fusco-purpurea polysaccharide (BFP) showed antimicrobial activity on E. coli. • BFP reduced biofilm formation in E. coli and weakened their infection potential. • BFP achieved antimicrobial activity by regulating the metabolites in E. coli cells. • BFP reduced biofilm formation in E. coli by down-regulating two-component system. • BFP can be used as a natural antibacterial agent in food or pharmaceuticals. [ABSTRACT FROM AUTHOR]

A large amount of carrageenan residue containing perlite is produced in carrageenan process. Management of carrageenan residue is an environmental issue in carrageenan green and clean production. Repeated recovery of perlite from carrageenan residue could reduce resource waste and environmental pollution. However, research on methods, reuse characteristics, and mechanisms of repeatedly recovered perlite remains lacking. In this study, a green recovery scheme was obtained to recover perlite by combining food-grade hydrochloric acid and hydrogen peroxide, and influence of elemental structure changes on gel structure during repeated recovery was investigated. The permeability of recovered perlite (2.61/Darcy) reached reuse standard, showing good economic value. The C–O–C bond of polysaccharide and inner ether galactose ring in carrageenan residue were degraded by hydrogen peroxide and hydrochloric acid. More importantly, gel strength and transparency of carrageenan increased by 42.86% and 16.46% with recycling times, probably due to repeated adsorption and release of K+ from recovered perlite. The C–K bond effectively shielded electrostatic repulsion between carrageenan segments and promotes formation of gel network. The characteristics of carrageenan and recycling times were consistent with gaussian model, y = y 0 + A w π / 2 e − 2 (x − x c) 2 w 2 , with a maximum number of cycles of 4.21. It provides a technical research basis for green and clean carrageenan extraction. [Display omitted] • Perlite was repeatedly recovered from carrageenan residue by combining extraction with low concentration of food-grade hydrogen peroxide and hydrochloric acid treatment method and reused for extraction of carrageenan. • The industrial production profit of recovered perlite could reach ¥ 1065.3/ton. • Management of carrageenan residue could improve the utilization rate of waste and reduce the waste of resources. • Recovered perlite was used to extract carrageenan, gel strength and transparency of carrageenan increased by 42.86% and 16.46%. • The characteristics of carrageenan and recycling times were consistent with gaussian model, y = y 0 + A w π / 2 e − 2 (x − x c) 2 w 2 , with a maximum number of cycles of 4.21. [ABSTRACT FROM AUTHOR]

Platinum-based chemotherapy remains the first-line treatment for ovarian carcinoma by inducing DNA damage. The therapeutic impact of clonal and subclonal somatic mutations in DNA damage repair (DDR) pathways remains unexplored. We performed an integrated analysis to infer the clonality of somatic deleterious mutations in 385 ovarian carcinomas treated with platinum-based chemotherapy. The Kaplan–Meier method was performed for visualization and the differences between survival curves were calculated by log-rank test. Proportional hazards models were used to estimate relative hazards for platinum-free interval (PFI), progression-free survival (PFS) and overall survival (OS). We found that somatic deleterious mutations in DDR pathways exhibited widespread clonal heterogeneity, and that patients with DDR clonal mutations exhibited a "hypermutator phenotype". Clonal somatic mutations in homologous recombination repair (HRR) pathway were significantly associated with better OS (HR = 0.19 (95% CI, 0.06–0.59), P = 0.0044) and PFS (HR = 0.20 (95% CI, 0.08–0.49), P = 0.0005) than HRR wild-type, while HRR subclonal mutations were not associated with prognosis. Moreover, HRR clonal mutations were associated with significantly higher chemotherapy sensitive rate (P = 0.0027) and longer PFI (HR = 0.20 (95% CI, 0.08–0.49), P = 0.0005) than HRR wild-type, while HRR subclonal mutations were not. We validated our findings using an independent cohort of 93 ovarian cancer patients that received platinum-based chemotherapy. HRR clonal mutations, but not subclonal mutations, were associated with improved survival, chemotherapy response, and genome instability compared with HRR wild-type. • Somatic mutations in homologous recombination repair (HRR) pathway exhibit widespread clonal heterogeneity. • HRR clonal mutations, but not subclonal mutations, are associated with chemotherapy response and improved survival. • HRR clonal mutation needs further validating as biomarker to identify patients that benefit from platinum-based chemotherapy. [ABSTRACT FROM AUTHOR]

κ-Carrageenase can degrade κ-carrageenan to produce bioactive κ-carrageenan oligosaccharides (KCOs) that have potential applications in pharmaceutical, food, agricultural, and cosmetics industries. Immobilized enzymes gain their popularity due to their good reusability, enhanced stability, and tunability. In this study, the previously characterized catalytic domain of Pseudoalteromonas purpurea κ-carrageenase was covalently immobilized on the synthesized amine-modified zeolitic imidazolate framework-8 nanoparticles with the formation of cross-linked enzyme aggregates, and the immobilized κ-carrageenase was further characterized. The immobilized κ-carrageenase demonstrated excellent pH stability and good reusability, and exhibited higher optimal reaction temperature, better thermostability, and extended storage stability compared with the free enzyme. The KCOs produced by the immobilized κ-carrageenase could significantly decrease the TC, TG, and LDL-C levels in HepG2 cells, increase the HDL-C level in HepG2 cells, and reduce the free fatty acids level in Caco-2 cells. Biochemical assays showed that the KCOs could activate AMPK activity, increase the ratios of p-AMPK/AMPK and p-ACC/ACC, and downregulate the expression of the lipid metabolism related proteins including SREBP1 and HMGCR in the hyperlipidemic HepG2 cells. This study provides a novel and effective method for immobilization of κ-carrageenase, and the KCOs produced by the immobilized enzyme could be a potential therapeutic agent to prevent hyperlipidemia. • κ-Carrageenase-CLEA is immobilized on amine-modified ZIF-8. • Stability and reusability of immobilized κ-carrageenase are enhanced. • Immobilized κ-carrageenase efficiently produces κ-carrageenan oligosaccharides. • κ-Carrageenan oligosaccharides show hypolipidemic activity in HepG2 cells. • κ-Carrageenan oligosaccharides can regulate lipid metabolism by activating AMPK pathway. [ABSTRACT FROM AUTHOR]

Highlights • β-Agarase was immobilized on tannic acid modified-Fe 3 O 4 magnetic nanoparticles. • The immobilized β-agarase showed excellent pH, thermal stability and reusability. • Neoagaro-oligosaccharide were successfully prepared by immobilized β-agarase. • Neoagaro-oligosaccharide obtained revealed varying activity in antioxidant. Abstract β-Agarase was immobilized by using tannic acid modified-Fe 3 O 4 magnetic nanoparticles (TA-MNPs) as a support material. The MNPs were synthesized by improved chemical coprecipitation method and modified with TA for agarase immobilization. TA-MNPs and immobilized β-agarase were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and thermal gravimetric analysis (TGA), all of which indicated the successful surface modification of MNPs with TA and the immobilization of β-agarase. The optimal immobilization conditions for 25 mg TA-MNPs included 100 r/min oscillation speed, immobilization time of 2 h, immobilization temperature of 15 °C, and initial β-agarase concentration of 3 mL (480 U). Immobilized β-agarase showed better pH and thermal stability and excellent reusability than the free enzyme. Results revealed the promising application of β-agarase-TA-MNPs for the preparation of neoagaro-oligosaccharides with different average polymerization degrees and varying activities in the antioxidant. [ABSTRACT FROM AUTHOR]

Enzymatic browning is one of the major problems in food industry, especially for damaged fruits and vegetables during post-harvest handling and processing. An efficient approach to reduce enzymatic browning is to inhibit key polyphenol oxidases causing browning reactions, for example tyrosinase. Tyrosinase inhibitors from natural sources are more attractive considering the importance of food safety and application. B. fusco-purpurea is a edible alga with potential inhibiting tyrosinase. Therefore, we purified and characterized new tyrosinase inhibitors from the seaweed. Phytol, identified in the crude extract of B. fusco-purpurea inhibited tyrosinase with half maximal inhibitory concentration (IC 50) of 32.4 ± 3.06 μg/mL as a reversible and competitive inhibitor. Phytol acted as tyrosinase inhibitor, antioxidant, and reducing agent in inhibition of enzymatic browning mechanisms. Then, with the increase concentration of phytol added in homogenates squeezed from apple, pear, and potato, higher browning inhibition was observed with browning index increased. Our findings suggest that phytol isolated from edible red alga could be a potential anti-browning agent. • Phytol of natural origin stronger inhibited tyrosinase. • Inhibition of tyrosinase is a new anti-browning effect of phytol. • Inhibition of tyrosinase by phytol is reversable and dose-dependent. • Phytol altered structure of tyrosinase. • Phytol is a potential food additive with anti-browning for food preservation. [ABSTRACT FROM AUTHOR]

This study was aimed to investgate the effects of steam explosion (SE) with different temperatures at 120–220 °C on the physicochemical, functional and structural properties of pomelo fruitlets. SE treatment changed monosaccharide composition, increased total dietary fiber (TDF) and soluble dietary fiber (SDF) contents of pomelo fruitlets. Especially at 160 °C SE treatment, TDF and SDF content was 13.57% and 25.94% higher than that of the control one (p < 0.05). Moreover, water- and oil-holding capacity, swelling capacity, and in vitro hypolipidemic activity (based on bile acid salt binding capacities increased by 7.95%–17.13% and pancreatic lipase inhibition capacities increased by 2.46%–6.75%) of pomelo fruitlets were significantly increased by appropriate SE conditions at 140–160 °C. This might be related to the fragmentation and porous surface structure of SE treated sample. In addition, SE treated pomelo fruitlets had higher crystallinity and thermal stability due to the rearrangement of cellulose molecular chains. It was revealed that SE treatment can effectively improve the physicochemical properties and hypolipidemic activity of pomelo fruitlets through structural changes. Our findings can provide the theoretical basis for the high value application of pomelo fruitlets as functional products through SE modification. • SE increased TDF and SDF contents in pomelo fruitlets especially at 160 °C. • SE changed microstructure of pomelo fruitlets with more fragmentation and porous structure. • SE treated pomelo fruitlets had higher crystallinity and thermal stability. • SE improved hydration capacity and hypolipidemic activity of pomelo fruitlets. [ABSTRACT FROM AUTHOR]

This study was to investigate the structure and antioxidant activity of Porphyra haitanensis polysaccharides (PHPs) extracted by different methods, including water extraction (PHP), ultra-high pressure (UHP-PHP), ultrasonic (US-PHP) and microwave assisted water extraction (M-PHP). Compared with water extraction, the total sugar, sulfate and uronic acid contents of PHPs was enhanced by ultra-high pressure, ultrasonic and microwave assisted treatments, especially those of UHP-PHP were increased by 24.35 %, 12.84 % and 27.51 %, respectively (p < 0.05). Meanwhile, these assisted treatments affected the monosaccharide ratio of polysaccharides and significantly reduced the protein content, molecular weight as well as particle size of PHPs (p < 0.05), and resulted in a loose microstructure with more porosity and fragments. PHP, UHP-PHP, US-PHP, and M-PHP all possessed in vitro antioxidant capacity. Among them, UHP-PHP had the strongest oxygen radical absorbance capacity, DPPH and ·OH radicals scavenging capacities, which increased by 48.46 %, 116.24 %, and 14.98 % respectively. Moreover, PHPs particularly UHP-PHP effectively increased the cell viability and reduced ROS levels of H 2 O 2 induced RAW264.7 cells (p < 0.05), indicating their good effects against cell oxidative damage. The findings suggested that PHPs with ultra-high pressure assisted treatments has the better potential to develop natural antioxidant. [ABSTRACT FROM AUTHOR]

In this study, high-pressure homogenization (HPH) technique was applied for the pretreatment of Bangia fusco-purpurea , and the effect of HPH on the composition, physiochemical and functional properties, and in vitro anti-glycation activity of dietary fiber from this seaweed (B. fusco-purpurea dietary fiber, BDF) was studied. Results showed that HPH significantly increased water-soluble dietary fiber (SDF) content in BDF. Water-holding capacity, oil-holding capacity, and glucose delay dialysis index of BDF were significantly enhanced after HPH treatment. Additionally, HPH significantly improved the in vitro anti-glycation activity of BDF by inhibiting the formation of advanced glycation end products (AGEs) and mitigating damage induced by AGEs on intestinal cells. These improvements could be attributed to the formation of the coarse and porous structure and greater exposure of hydroxyl groups of BDF caused by HPH treatment. These results implied the potential of HPH in seaweed processing and provided a scientific basis for the in-depth, comprehensive utilization of B. fusco-purpurea. HPH is an emerging non-thermal food processing technique with promising application potential in food industry. In this study, we found that HPH technique could significantly change the composition, improve physiochemical and functional properties and enhance anti-glycation activity of dietary fiber from seaweed B. fusco-purpurea. Our results validated the efficiency of HPH on dietary fiber modification, implying the potential of HPH in food industry and healthy industry. [Display omitted] • SDF content in DF from Bangia fusco-purpurea after HPH treatment (HBDF) was increased. • HPH treatment led to the formation a porous and loose structure of HBDF. • HBDF exhibited better water holding capacity and oil holding capacity. • HPH treatment significantly increased glucose delay retention index of HBDF. • In vitro anti-glycation activity of HBDF was increased after HPH treatment. [ABSTRACT FROM AUTHOR]

κ-Carrageenase provides an attractive enzymatic approach to preparation of κ-carrageenan oligosaccharides. Pseudoalteromonas tetraodonis κ-carrageenase is active at the alkaline conditions but displays low thermostability. To further improve its enzymatic performance, two mutants of Q42V and I51H exhibiting both improved thermostability and enzyme activity were screened by the PoPMuSiC algorithm. Compared with the wild-type κ-carrageenase (WT), Q42V and I51H increased the enzyme activity by 20.9% and 25.4%, respectively. After treatment at 50 ℃ for 40 min, Q42V and I51H enhanced the residual activity by 31.1% and 25.9%, respectively. The T m values of Q42V, I51H, and WT determined by differential scanning calorimetry were 58.2 ℃, 54.8 ℃, and 51.2 ℃, respectively. Compared with untreated and HCl-treated κ-carrageenans, Q42V-treated κ-carrageenan exhibited higher pancreatic lipase inhibitory activity. Molecular docking analysis indicated that the additional pi-sigma force and hydrophobic interaction in the enzyme-substrate complex could account for the increased catalytic activity of Q42V and I51H, respectively. Molecular dynamics analysis indicated that the improved thermostability of mutants Q42V and I51H could be attributed to the less structural deviation and the flexible changes of enzyme conformation at high temperature. This study provides new insight into κ-carrageenase performance improvement and identifies good candidates for their industrial applications. • Mutant κ-carrageenases Q42V and I51H are screened by the PoPMuSiC algorithm. • Q42V and I51H increase the thermostability and catalytic activity simultaneously. • Q42V-treated κ-carrageenan exhibits high pancreatic lipase inhibitory activity. [ABSTRACT FROM AUTHOR]

Red seaweed contains abundant bioactive ingredients with health benefits. Fermentation is widely used in improving the bioactive ingredients of seaweed materials. However, the types of the active metabolite and changes in biological activity components by the fermentation process remain unknown. In this study, red seaweed Bangia fusco-purpurea was inoculated with Lactobacillus delbrueckii and Lactobacillus plantarum to study bioactive components in supernatants. Results showed that Lactobacillus -fermentation dramatically increased free essential amino acid, trace mineral elements, flavonoids, and polyphenols contents, while decreasing protein and sugar in supernatants. Meanwhile, inhibitions of pancreatic lipase enzyme activities and antibacterial activities against oral pathogenic bacteria were significantly increased by Lactobacillus -fermentation, up to 93.48% and 98.2%, respectively. It might be caused by the increase of polyphenols and flavonoids contents in fermentation supernatants. Also, the biological functions of L. delbrueckii -fermentation were better than that of L. plantarum. Overall, B. fusco-purpurea with Lactobacillus -fermentation has the potential to be special dietary food for improving hyperlipidemia and obesity. [Display omitted] • B. fusco-purpurea was inoculated with Lactobacillus to study bioactive components. • Lactobacillus -fermentation increased polyphenols, essential amino acid and minerals. • Inhibition of pancreatic lipase activity and antibacterial activity were increased. • Fermentation of B. fusco-purpurea is special dietary for hyperlipidaemia and obesity. [ABSTRACT FROM AUTHOR]

Alginate lyases can depolymerize alginate to oligomers with potential applications in many fields. Here a new alginate lyase, namely AlgL6, was characterized from Microbulbifer sp. ALW1, phylogenetically classified into the polysaccharide lyase family 6 (PL6). The recombinant alginate lyase AlgL6 exerted enzymatic activities towards polymannuronate, polyguluronate, and sodium alginate in an exolytic manner. AlgL6 had an optimum temperature of 35 °C and good stability at 30 °C or below. Its optimum pH was 8.0, and it had good stability over the pH range of 5.0–9.0. AlgL6 exhibited excellent halo-stability against Na+, and its activity can be increased up to about 1.8 times by 0.5 M NaCl. AlgL6 also showed strong stability in the presence of some nonionic detergents such as Tween 20 and Tween 80. The degradation products of sodium alginate by AlgL6 exhibited more effective antioxidant activities than the undigested polysaccharides. Structure analysis illustrated the catalytic mechanism defined by the coordination of the acid/base residues Arg269 and Lys248 of AlgL6. The replacement of Ca2+-interacting amino acid residues in AlgL6 and depletion of Ca2+ suggested the involvement of Ca2+ in the enzyme's catalytic activity. These properties of AlgL6 supply support to its industrial application for development of alginate bioresource. • AlgL6 exhibits excellent halo-stability against Na+. • AlgL6 has calcium-dependence catalysis property. • AlgL6 has a great potential as an exo-type tool to produce bioactive AOS. [ABSTRACT FROM AUTHOR]

In this study, Discovery Studio was employed to predict the potential disulfide bond mutants of the catalytic domain of Pseudoalteromonas porphyrae κ-carrageenase to improve the catalytic activity and thermal stability. The mutant N205C-G239C was identified with significantly increased catalytic activity toward κ-carrageenan substrate, with activity 4.28 times that of WT. The optimal temperature of N205C-G239C was 55 °C, 15 °C higher than that of WT. For N205C-G239C, the t 1/2 value at 50 °C was 52 min, 1.41 times that of WT. The microstructural analysis revealed that the introduced disulfide bond N205C-G239C could create a unique catalytic environment by promoting favorable interactions with κ-neocarratetraose. This interaction impacted various aspects such as product release, water molecule network, thermodynamic equilibrium, and tunnel size. Molecular dynamics simulations demonstrated that the introduced disulfide bond enhanced the overall structure rigidity of N205C-G239C. The results of substrate tunnel analysis showed that the mutation led to the widening of the substrate tunnel. The above structure changes could be the possible reasons responsible for the simultaneous enhancement of the catalytic activity and thermal stability of mutant N205C-G239C. Finally, N205C-G239C exhibited the effective hydrolysis of the κ-carrageenan industrial waste residues, contributing to the recycling of the oligosaccharides and perlite., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cardiac myxoma is a commonly encountered tumor within the heart that has the potential to be life-threatening. However, the cellular composition of this condition is still not well understood. To fill this gap, we analyzed 75,641 cells from cardiac myxoma tissues based on single-cell sequencing. We defined a population of myxoma cells, which exhibited a resemblance to fibroblasts, yet they were distinguished by an increased expression of phosphodiesterases and genes associated with cell proliferation, differentiation, and adhesion. The clinical relevance of the cell populations indicated a higher proportion of myxoma cells and M2-like macrophage infiltration, along with their enhanced spatial interaction, were found to significantly contribute to the occurrence of embolism. The immune cells surrounding the myxoma exhibit inhibitory characteristics, with impaired function of T cells characterized by the expression of GZMK and TOX, along with a substantial infiltration of tumor-promoting macrophages expressed growth factors such as PDGFC. Furthermore, in vitro co-culture experiments showed that macrophages promoted the growth of myxoma cells significantly. In summary, this study presents a comprehensive single-cell atlas of cardiac myxoma, highlighting the heterogeneity of myxoma cells and their collaborative impact on immune cells. These findings shed light on the complex pathobiology of cardiac myxoma and present potential targets for intervention., (© 2024. The Author(s).)

Fungal infection has become a major threat to crop loss and affects food safety. The waste water from agar processing industries extraction has a number of active substances, which could be further transformed by microorganisms to synthesize antifungal active substances. In this study, Bacillus subtilis was used to ferment the waste water from agar processing industries extraction to analyze the antifungal activity of the fermentation broth on Alternaria alternata and Alternaria spp. Results showed that 25% of the fermentation broth was the most effective in inhibited A. alternata and Alternaria spp., with fungal inhibition rates of 99.9% and 96.1%, respectively, and a minimum inhibitory concentration (MIC) was 0.156 μg/mL. Metabolomic analysis showed that flavonoid polyphenols such as coniferyl aldehyde, glycycoumarin, glycitin, and procyanidin A1 may enhance the inhibitory activity against the two pathogenic fungal strains. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that polyphenols involved in the biosynthesis pathways of isoflavonoid and phenylpropanoid were upregulated after fermentation. The laser confocal microscopy analyses and cell conductivity showed that the cytoplasm of fungi treated with fermentation broth was destroyed. This study provides a research basis for the development of new natural antifungal agents and rational use of seaweed agar waste. KEY POINTS: • Bacillus subtilis fermented waste water has antifungal activity • Bacillus subtilis could transform active substances in waste water • Waste water is a potential raw material for producing antifungal agents., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Poor thermostability reduces the industrial application value of κ-carrageenase. In this study, the PoPMuSiC algorithm combined with site-directed mutagenesis was applied to improve the thermostability of the alkaline κ-carrageenase from Pseudoalteromonas porphyrae. The mutant E154A with improved thermal stability was successfully obtained using this strategy after screening seven rationally designed mutants. Compared with the wild-type κ-carrageenase (WT), E154A improved the activity by 29.4% and the residual activity by 51.6% after treatment at 50 °C for 30 min. The melting temperature (T m ) values determined by circular dichroism were 66.4 °C and 64.6 °C for E154A and WT, respectively. Molecular dynamics simulation analysis of κ-carrageenase showed that the flexibility decreased within the finger regions (including F1, F2, F3, F5 and F6) and the flexibility improved in the catalytic pocket area of the mutant E154A. The catalytic tunnel dynamic simulation analysis revealed that E154A led to enlarged catalytic tunnel volume and increased rigidity of the enzyme-substrate complex. The increasing rigidity within the finger regions and more flexible catalytic pocket of P. porphyrae κ-carrageenase might be a significant factor for improvement of the thermostability of the mutant κ-carrageenase E154A. The proposed rational design strategy could be applied to improve the enzyme kinetic stability of other industrial enzymes. Moreover, the hydrolysates of κ-carrageenan digested by the mutant E154A demonstrated increased scavenging activities against hydroxyl (OH) radicals and 2,2'-azinobis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) radicals compared with the undigested κ-carrageenan., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

The industrial applications of the κ-carrageenases have been restricted by their poor thermostability. In this study, based on the folding free energy change (ΔΔG) and the flexibility analysis using molecular dynamics (MD) simulation for the alkaline κ-carrageenase KCgCD from Pseudoalteromonas porphyrae (WT), the mutant S190R was identified with improved thermostability. After incubation at 50 °C for 30 min, the residual activity of S190R was 63.7%, 25.7% higher than that of WT. The T m values determined by differential scanning calorimetry were 66.2 °C and 64.4 °C for S190R and WT, respectively. The optimal temperature of S190R was 10 °C higher than that of WT. The κ-carrageenan hydrolysates produced by S190R showed higher xanthine oxidase inhibitory activity compared with the untreated κ-carrageenan. MD simulation analysis of S190R showed that the residues (V186-M194 and P196-G197) in F5 and the key residue R150 in F3 displayed the decreased flexibility, and residues of T169-N173 near the catalytic center displayed the increased flexibility. These changed flexibilities might be the reasons for the improved thermostability of mutant S190R. This study provides a useful rational design strategy of combination of ΔΔG calculation and MD simulation to improve the κ-carrageenase's thermostability for its better industrial applications., (© 2024. The Author(s).)

Herein, we studied the in vitro -simulated intestinal flora fermentation of Porphyra haitanensis polysaccharides (PHPs) with microwave, ultrasonic, ultra-high pressure-assisted extraction and the protective effect of their fermented products against HT-29 human colon cancer cells. The results showed that PHPs were largely degraded at the 18 h stage of ascending colon fermentation, further greatly increasing the contents of reducing sugars and short-chain fatty acids ( p < 0.05). Particularly, the PHPs subjected to ultra-high pressure-assisted extraction (UHP-PHP) showed the highest reducing sugar content of 1.68 ± 0.01 mg mL -1 and butyric acid content of 410.77 ± 7.99 mmol mL -1 . Moreover, UHP-PHP showed a better effect in increasing the ratio of Bacteroidetes / Firmicutes and decreasing the abundance of Proteobacteria and Escherichia coli . PHPs could protect against HT-29 cells by increasing the ROS levels in a concentration-dependent manner, especially UHP-PHP fermented in a descending colon for 24 h. This was related to the up-regulated apoptosis-related genes (Bax and Bak), down-regulated protein expression of Bcl-2 and activation of the p -AKT protein, thereby promoting the apoptosis of HT-29 cells. Our results can facilitate the modification of PHPs and their practical application in the development of intestinal health improving products.

Background: Gastroduodenal artery (GDA) stump erosion hemorrhage is a fatal complication after pancreaticoduodenectomy. This study aimed to determine whether GDA stump wrapping with the teres hepatis ligament during pancreaticoduodenectomy decreased the incidence of postpancreatectomy hemorrhage (PPH)., Methods: We reviewed 307 patients who had undergone pancreaticoduodenectomy between March 2019 and June 2022. The patients were divided into two groups according to application of GDA stump wrapping with the teres hepatis ligament: GDA wrapping group (165 patients) and no-wrapping group (142 patients). The perioperative data were compared between the groups., Results: The clinical characteristics were balanced between the two groups. Grades B and C PPH and GDA-stump-related hemorrhage were significantly reduced in the GDA wrapping group compared with the no-wrapping group (PPH B/C, 13.4% vs 6.1%, P = 0.029; GDA hemorrhage, 5.6% vs 0.6%, P = 0.014). No difference was observed in the incidence of clinically relevant postoperative pancreatic fistula, biliary leak, intra-abdominal abscess, delayed gastric emptying, 90-day mortality, and postoperative hospital stay between the two groups., Conclusion: Wrapping GDA stump with the teres hepatis ligament reduced the incidence of GDA-stump-related PPH. Therefore, the wrapping technique is a simple and effective strategy to prevent PPH. Prospective studies are needed to confirm the benefit of this procedure., (© 2023. The Author(s).)

Background: Targeting EBV-proteins with mRNA vaccines is a promising way to treat EBV-related tumors like nasopharyngeal carcinoma (NPC). We assume that it may sensitize tumors to immune checkpoint inhibitors., Results: We developed an LMP2-mRNA lipid nanoparticle (C2@mLMP2) that can be delivered to tumor-draining lymph nodes. C2@mLMP2 exhibited high transfection efficiency and lysosomal escape ability and induced an increased proportion of CD8 + central memory T cells and CD8 + effective memory T cells in the spleen of the mice model. A strong synergistic anti-tumor effect of C2@mLMP2 in combination with αPD-1 was observed in tumor-bearing mice. The mechanism was identified to be associated with a reverse of CD8 + T cell exhaustion in the tumor microenvironment. The pathological analysis further proved the safety of the vaccine and the combined therapy., Conclusions: This is the first study proving the synergistic effect of the EBV-mRNA vaccine and PD-1 inhibitors for EBV-related tumors. This study provides theoretical evidence for further clinical trials that may expand the application scenario and efficacy of immunotherapy in NPC., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Although cancer immunotherapy is a compelling approach against cancer, its effectiveness is hindered by the challenge of generating a robust and durable immune response against metastatic cancer cells. Nanovaccines, specifically engineered to transport cancer antigens and immune-stimulating agents to the lymph nodes, hold promise in overcoming these limitations and eliciting a potent and sustained immune response against metastatic cancer cells. This manuscript provides an in-depth exploration of the lymphatic system's background, emphasizing its role in immune surveillance and tumor metastasis. Furthermore, it delves into the design principles of nanovaccines and their unique capability to target lymph node metastasis. The primary objective of this review is to provide a comprehensive overview of the current advancements in nanovaccine design for targeting lymph node metastasis, while also discussing their potential to enhance cancer immunotherapy. By summarizing the state-of-the-art in nanovaccine development, this review aims to shed light on the promising prospects of harnessing nanotechnology to potentiate cancer immunotherapy and ultimately improve patient outcomes., (© 2023. The Author(s).)

Astaxanthin is a valuable carotenoid and is used as antioxidant and health care. Phaffia rhodozyma is a potential strain for the biosynthesis of astaxanthin. The unclear metabolic characteristics of P. rhodozyma at different metabolic stages hinder astaxanthin's promotion. This study is conducted to investigate metabolite changes based on quadrupole time-of-flight mass spectrometry metabolomics method. The results showed that the downregulation of purine, pyrimidine, amino acid synthesis, and glycolytic pathways contributed to astaxanthin biosynthesis. Meanwhile, the upregulation of lipid metabolites contributed to astaxanthin accumulation. Therefore, the regulation strategies were proposed based on this. The addition of sodium orthovanadate inhibited the amino acid pathway to increase astaxanthin concentration by 19.2%. And the addition of melatonin promoted lipid metabolism to increase the astaxanthin concentration by 30.3%. It further confirmed that inhibition of amino acid metabolism and promotion of lipid metabolism were beneficial for astaxanthin biosynthesis of P. rhodozyma. It is helpful in understanding metabolic pathways affecting astaxanthin of P. rhodozyma and provides regulatory strategies for metabolism., (© 2023 John Wiley & Sons Ltd.)

Background: Ex vivo liver resection and autotransplantation (ELRAT) may provide an opportunity for R0 resection of conventionally unresectable hepatobiliary cancers and hepatic metastases. To date, few studies of the surgery for malignant tumors have been conducted and there are no known reports of in vivo partial hepatectomy followed by ELRAT (IPH-ELRAT) for malignant tumors., Methods: Between December 2021 and November 2022, ten patients with malignant hepatobiliary primary cancers or hepatic metastases underwent ELRAT at our institution. We shared the surgical skills and postoperative prognoses of these patients were assessed., Results: The types of tumors were biliary tract cancer (BTC, n=8), hepatic metastasis of colonic carcinoma (n=1), and hepatic metastasis of small-bowel stromal tumor (n=1). Five patients underwent in vivo total hepatectomy followed by ex vivo liver resection and autotransplantation (ITH-ELRAT), The other five received in vivo partial hepatectomy followed by ex vivo liver resection and autotransplantation (IPH-ELRAT). Four patients underwent inferior vena cava replacement using artificial blood vessels. The survival rate of all ten patients one month after surgery was 100%. Nine patients (90%) are currently alive, with a median follow-up of 8.5 months (range 6-16.5 months). To date, seven of the nine surviving patients have had no cancer recurrence, including six with BTC., Conclusions: We report the world first five cases that received IPH-ELRAT for malignancies. We also demonstrated relatively favorable outcomes in patients who underwent ELRAT. ELRAT may be a recommendable surgical option for selected patients with conventionally unresectable hepatobiliary malignant tumors., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Xu, Hu, Jiang, Li, Zhou, Gao and Yan.)

There is a growing global demand for clean energy, driven by concerns over global warming and the need to decrease greenhouse gas emissions. This research uses a nonparametric approach to analyze the correlation between industrialization and the use of clean energy sources in 16 countries between 1995 and 2020. We utilize a technique called the local linear dummy variable estimate to monitor the effects of globalization on the development of sustainable power over time. An unfavorable and economically important link was found between industrialization and the use of sustainable energy supplies from 2003 to 2012, as determined by an examination of nonparametric econometric techniques. Still, it started moving in the opposite direction, becoming significant and positive after 2014. In addition, we discover that globalization has various effects on the various indices of the use of renewable energy sources. The research also reveals that the effects of globalization on RES vary across different regions, with some regions experiencing more significant benefits than others. Overall, the study provides valuable insights into the complex relationship between globalization and RES and highlights the need for further research to inform policy decisions and promote sustainable development., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The effect of black tea powder on the antioxidant activity and gel characteristics of fish balls from silver carp were investigated after freezing storage for 7 days. The results show that black tea powder with different concentrations of 0.1%, 0.2% and 0.3% ( w / w ) could significantly increase the antioxidant activity of fish balls ( p < 0.05). In particular, at the concentration of 0.3%, the antioxidant activity was the strongest among these samples, where the reducing power, DPPH, ABTS and OH free radical scavenging rate were up to 0.33, 57.93%, 89.24% and 50.64%, respectively. In addition, black tea powder at the level of 0.3% significantly increased the gel strength, hardness and chewiness while greatly reducing the whiteness of the fish balls ( p < 0.05). ESEM observation found that the addition of black tea powder could promote the crosslinking of proteins and reduced the pore size of the gel network structure of the fish balls. The results suggest that black tea powder could be used as a natural antioxidant and gel texture enhancer in fish balls, which we found to be much related to the phenolic compounds of black tea powder.

Background: Recently, in many Asian centers, laparoscopic anatomical liver resection (LALR) using the indocyanine green (ICG) fluorescence imaging technique has been increasingly applied in resecting hepatocellular carcinoma, even in colorectal liver metastases. However, LALR techniques have not been fully standardized, especially in right superior segments. Due to the anatomical position, prevailing positive staining using a PTCD (percutaneous transhepatic cholangial drainage) needle was superior to negative staining in right superior segments hepatectomy, while it was difficult to manipulate. Herein, we design a novel method of ICG-positive staining for LALR of right superior segments., Methods: Between April 2021 and October 2022, we retrospectively studied patients in our institute who underwent LALR of right superior segments using a novel method of ICG-positive staining, which comprised a customized puncture needle and an adaptor. Compared to the PTCD needle, the customized needle was not limited by the abdominal wall and could be punctured from the liver dorsal surface, which was more flexible to manipulate. The adapter was attached to the guide hole of the laparoscopic ultrasound (LUS) probe to ensure the precise puncture path of the needle. Guided by preoperative three-dimensional (3D) simulation and intraoperative laparoscopic ultrasound imaging, we punctured the transhepatic needle into the target portal vein through the adaptor and then slowly injected 5-10 ml of 0.025 mg/ml ICG solution into the vessel. LALR can be guided by the demarcation line under fluorescence imaging after injection. Demographic, procedural and postoperative data were collected and analyzed., Results: In this study, 21 patients underwent LALR of the right superior segments with ICG fluorescence-positive staining, and the procedures had a success rate of 71.4%. The average staining time was 13.0 ± 6.4 min, the operative time was 230.4 ± 71.7 min, R0 resection was 100%, the postoperative hospital stay was 7.1 ± 2.4 days, and no severe puncture complications occurred., Conclusions: The novel customized puncture needle approach seems to be feasible and safe for ICG-positive staining in LALR of right superior segments, with a high success rate and a short staining time., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Jiang, Zhou, Zheng, Li, Gao, Tian, Shao, Xu and Yan.)

Polysaccharide extracted from red seaweed Bangia fusco-purpurea (BFP) is a novel sulfated galactan, differed from agarans and carrageenans in fine structure. In this study, in vitro fermentation characteristics of BFP by human gut microbiota and its protective effect on lipopolysaccharide (LPS)-induced injury in Caco-2 cells were investigated. Our results showed that BFP was mainly degraded at transverse colon for 18 h fermentation by gut microbiota with reduced molecular weight. Meanwhile, BFP fermentation was associated with increased short-chain fatty acids (SCFAs) as compared to control group, especially acetic acid was increased to 129.53 ± 0.24 from 82.14 ± 0.23 mmol/L, and butyric acid was up to 1.56 ± 0.004 from 0.62 ± 0.01 mmol/L. Furthermore, BFP promoted abundances of Bacteroidetes and Firmicutes, while decreased numbers of Proteobacteria. The up-regrated beneficial differential metabolites were SCFAs, L-proline, arginine, folic acid, pyridoxamine, thiamine, etc. (p < 0.05), and their related metabolic pathways mainly included mTOR, arginine biosynthesis, and vitamin metabolism. Notably, BFP fermentation products at transverse colon significantly restored cell viability of LPS-treated Caco-2 cells from 73.79 ± 0.48 % to 93.79-99.64 %, which might be caused by increased beneficial differential metabolites (e.g., SCFAs). Our findings suggest that BFP has prebiotic potential and can enhance gut health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Marine bacterium Microbulbifer sp. ALW1 was revealed to be able to effectively degrade Laminaria japonica thallus fragments into fine particles. Polysaccharide substrate specificity analysis indicated that ALW1 could produce extracellular alginate lyase, laminarinase, fucoidanase and cellulase. Based on alignment of the 16 S rRNA sequence with other reference relatives, ALW1 showed the closest relationship with Microbulbifer aggregans CCB-MM1 T . The cell morphology and some basic physiological and biochemical parameters of ALW1 cells were characterised. ALW1 is a Gram-negative, rod- or oval-shaped, non-spore-forming and non-motile bacterium. The DNA-DNA relatedness values of ALW1 with type strains of M. gwangyangensis (JCM 17,800), M. aggregans (JCM 31,875), M. maritimus (JCM 12,187), M. okinawensis (JCM 16,147) and M. rhizosphaerae (DSM 28,920) were 28.9%, 43.3%, 41.2%, 35.4% and 45.6%, respectively. The major cell wall sugars of ALW1 were determined to be ribose and galactose, which differed from other closely related species. These characteristics indicated that ALW1 could be assigned to a separate species of the genus Microbulbifer. The complete genome of ALW1 contained one circular chromosome with 4,682,287 bp and a GC content of 56.86%. The putative encoded proteins were categorised based on their functional annotations. Phenotypic, physiological, biochemical and genomic characterisation will provide insights into the many potential industrial applications of Microbulbifer sp. ALW1.Key points., (© 2022. The Author(s).)

T cells exhibit heterogeneous functional states, which correlate with responsiveness to immune checkpoint blockade and prognosis of tumor patients. However, the molecular regulatory mechanisms underlying the dynamic process of T cell state transition remain largely unknown. Based on single-cell transcriptome data of T cells in non-small cell lung cancer, we combined cell states and pseudo-times to propose a pipeline to construct dynamic regulatory networks for dissecting the process of T cell dysfunction. Candidate regulators at different stages were revealed in the process of tumor-infiltrating T cell dysfunction. Through comparing dynamic networks across the T cell state transition, we revealed frequent regulatory interaction rewiring and further refined critical regulators mediating each state transition. Several known regulators were identified, including TCF7 , EOMES , ID2 , and TOX . Notably, one of the critical regulators, TSC22D3 , was frequently identified in the state transitions from the intermediate state to the pre-dysfunction and dysfunction state, exerting diverse roles in each state transition by regulatory interaction rewiring. Moreover, higher expression of TSC22D3 was associated with the clinical outcome of tumor patients. Our study embedded transcription factors (TFs) within the temporal dynamic networks, providing a comprehensive view of dynamic regulatory mechanisms controlling the process of T cell state transition., Competing Interests: The authors declare no competing interests., (© 2021.)

Background: Triple-negative breast cancer (TNBC) is a clinically aggressive disease with abundant variants that cause homologous recombination repair deficiency (HRD). Whether TNBC patients with HRD are sensitive to anthracycline, cyclophosphamide and taxane (ACT), and whether the combination of HRD and tumour immunity can improve the recognition of ACT responders are still unknown., Methods: Data from 83 TNBC patients in The Cancer Genome Atlas (TCGA) was used as a discovery cohort to analyse the association between HRD and ACT chemotherapy benefits. The combined effects of HRD and immune activation on ACT chemotherapy were explored at both the genome and the transcriptome levels. Independent cohorts from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and Gene Expression Omnibus (GEO) were adopted to validate our findings., Results: HRD was associated with a longer ACT chemotherapy failure-free interval (FFI) with a hazard ratio of 0.16 (P = 0.004) and improved patient prognosis (P = 0.0063). By analysing both HRD status and ACT response, we identified patients with a distinct TNBC subtype (ACT-S&HR-P) that showed higher tumour lymphocyte infiltration, IFN-γ activity and NK cell levels. Patients with ACT-S&HR-P had significantly elevated immune inhibitor levels and presented immune activation associated with the increased activities of both innate immune cells and adaptive immune cells, which suggested treatment with immune checkpoint blockade as an option for this subtype. Our analysis revealed that the combination of HRD and immune activation enhanced the efficiency of identifying responders to ACT chemotherapy (AUC = 0.91, P = 1.06e-04) and synergistically contributed to the clinical benefits of TNBC patients. A transcriptional HRD signature of ACT response-related prognostic factors was identified and independently validated to be significantly associated with improved survival in the GEO cohort (P = 0.0038) and the METABRIC dataset (P < 0.0001)., Conclusions: These findings highlight that HR deficiency prolongs FFI and predicts intensified responses in TNBC patients by combining HRD and immune activation, which provides a molecular basis for identifying ACT responders., (© 2021. The Author(s).)

Alginate is a natural polysaccharide resource abundant in brown algae and it can be cleaved into alginate oligosaccharides by alginate lyase. Alginate lyases and the bioactive alginate oligosaccharides have been applied in diverse fields such as pharmaceutical therapy and nutraceutical supplementation. Immobilized enzymes greatly facilitate their industrial application owing to their reusability, stability, and tunability. In this study, magnetic Fe 3 O 4 nanoparticles were synthesized and used to immobilize an exolytic alginate lyase AlgL17 that was characterized previously. The immobilized AlgL17 demonstrated enhanced thermal and pH tolerance, extended storage stability, and moderate reusability. The mass spectrum indicated the specific activity of the immobilized AlgL17 to release alginate oligosaccharides (AOS) from alginate polysaccharide. The produced AOS exhibited their antioxidant and antiapoptotic activities in H 2 O 2 -stressed human umbilical vein endothelial cells by upregulation of reactive oxygen species scavenging activities and attenuation of the caspase-mediated apoptosis pathway., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Melanogenesis is a biosynthetic pathway to produce melanin pigment in melanocyte, involving a series of intricate enzymatic and chemical catalyzed reactions. Melanogenesis involves five signaling pathways that converge on microphthalmia-associated transcription factor. In addition, many cytokines, involved in the regulation of melanogenesis, play an important role in the development, proliferation, differentiation and migration of melanocytes. Polyoxometalate can be used as a potential inhibitor of melanin production. Hence, this paper reviews the signaling pathways of melanogenesis and their regulatory mechanism, to apply polyoxometalates in the melanin production pathway, and briefly introduces the regulatory factors of related pathways.