Recent development of carrier materials in anthocyanins encapsulation applications: A comprehensive literature review

Anthocyanins are natural polyphenols belonging to the flavonoid family that possess a variety of putative health benefits when consumed in a balanced diet. However, applications of anthocyanins in, for example, functional foods are limited due to poor stability, degradation, and low transmembrane efficiency. To maintain bioactivities of anthocyanins and optimize their use, various carrier materials have been developed. Here, we reviewed the uses of the different carrier materials (organic/inorganic, micro/nano) for anthocyanin encapsulation and delivery over the past five years. The performance of different materials and interactions between anthocyanins and these materials are described. Lastly, we give our perspective on the future development trend of anthocyanin encapsulation strategies.

Co-encapsulation of curcumin and anthocyanins in bovine serum album-fucoidan nanocomplex with a two-step pH-driven method

BACKGROUND

Curcumin (CUR) and anthocyanins (ACN) are recommended due to their bioactivities. However, their nutritional values and health benefits are limited by their low oral bioavailability. The incorporation of bioactive substances into polysaccharide-protein composite nanoparticles is an effective way to enhance their bioavailability. Accordingly, this study explored the fabrication of bovine serum albumin (BSA)-fucoidan (FUC) hybrid nanoparticles using a two-step pH-driven method for the delivery of CUR and ACN.

RESULTS

Under a 1:1 weight ratio of BSA to FUC, the point of zero charge moved from pH ⁓ 4.7 for BSA to around 2.5 for FUC-coated BSA, and the formation of BSA-FUC nanocomplex was pH-dependent by showing the maximum CUR emission wavelength shifting from 546 nm (CUR-loaded BSA-FUC at pH 4.7) and 544 nm (CUR/ACN-loaded BSA-FUC nanoparticles at pH 4.7) to 540 nm (CUR-loaded BSA-FUC at pH 6.0) and 539 nm (CUR/ACN-loaded BSA-FUC nanoparticles at pH 6.0). Elevated concentrations of NaCl from 0 to 2.5 mol L-1 caused particle size increase from about 250 to about 800 nm, but showing no effect on the encapsulation efficiency of CUR. The CUR and ACN entrapped, respectively, in the inner and outer regions of the BSA-FUC nanocomplex were released at different rates. After incubation for 10 h, more than 80% of ACN was released, while less than 25% of CUR diffused into the receiving medium, which fitted well to Logistic and Weibull models.

CONCLUSION

In summary, the BSA-FUC nanocomposites produced by a two-step pH-driven method could be used for the co-delivery of hydrophilic and hydrophobic nutraceuticals. © 2023 Society of Chemical Industry.

Stereoselective Synthesis of Xylodonin A and 22-Hydroxyxylodonin A and Discovery of Analogues with Cytotoxic Activity

The first and stereoselective synthesis of xylodonin A and 22-hydroxyxylodonin A, two drimane-type sesquiterpenoid natural products, was developed from the readily available (+)-sclareolide. This route features an allylic oxidation and acid-promoted dehydration for construction of the key intermediate 6-hydroxyisodrimenin. Representative analogues were synthesized, and their previously unknown bioactivities were revealed after biological evaluation. The analogue 19a exhibited cytotoxic activity against liver cancer HepG2 cells (IC50: 8.8 vs 5.9 μM) that was comparable to that of the clinical anticancer drug etoposide with lower toxicity to normal liver HL7702 cells (IC50 > 100 μM).

[The application of human genetic technology in the medical field urgently needs standardization]

Human gene editing technology is a hot spot and focus in the development of biotechnology, but it has also caused controversies over technical risks, genetic biosecurity, ethical dignity of human society and the legality of application, causing people to worry about the application of this technology. Gene editing for reproductive purposes is generally prohibited internationally, and countries have established legal regulatory systems to regulate the application of gene editing technology according to their own conditions. China shall establish a security risk access system for gene editing technology, ensure national biosecurity, establish and improve the system of ethical norms for scientific research, improve the construction of legislative standardization, and provide legal guarantees for the research and application of gene editing technology.

Chemical constituents from Uncaria laevigata and their anti-inflammatory activities and action mechanism

A new alkaloid 1* (scandine Z) and fourteen known natural products were isolated from 95% ethanol extract of Uncaria laevigata for the first time. Besides compound 1*, these fourteen compounds were firstly isolated from Uncaria laevigata. Excitedly, compound 4 exhibited strong anti-inflammatory activity (IC50 = 8.12 μmol/L), which wasn't described before. Moreover, compound 1* also de--monstrated certain anti-inflammatory activity (IC50 = 10.34 μmol/L). Network pharmacology suggested that compound 4 was involved in the IL-17 signalling pathway and the regulation of inflammation pathway. Molecular docking confirmed that it showed strong binding activity with the target protein (peroxisome proliferator-activated receptor γ, PPAR). Overall, compounds 1* and 4 exhibited strong anti-inflammatory activity and served as lead compounds and anti-inflammatory molecules for further study in vivo.

Antifouling and Self-Healing Performance of Marine Coatings Based on Hydrogen-Bond Interactions

Biofouling is an urgent problem that has to be solved in marine industries. As the traditional antifouling coating loses its antifouling ability after being damaged, the introduction of self-healing performance into the antifouling coating becomes a high priority. Accordingly, we report here a self-healing and antifouling polyurethane composite coating (PCL/MPU-Si/M) with the use of its carbonyl groups as multiple hydrogen bond acceptors. Its fabrication is carried out under mild and solvent-free conditions, forming a "cross-linking" network structure composed of alternately strong and weak bonds based on multiple carbonyl groups. The self-healing efficiency of PCL/MPU-Si/M in tensile strength is 85% after 48 h at room temperature, and higher temperatures can accelerate this self-healing process. Lubricant polydimethylsiloxane and antifoulant medetomidine endow the material with antifouling properties. The maximum antibacterial ability and algae inhibition coverage ability are 91.7 and 90.9%, respectively. This work provides a possible perspective for the design of antifouling and self-healing marine coatings.

Divergent and Stereoselective Synthesis of Ustusal A, (-)-Albrassitriol, and Elegansin D

The first synthesis of ustusal A as well as expeditious access to (-)-albrassitriol is described as featuring a singlet oxygen [4 + 2] cycloaddition, achieving the desired stereoselectivity for the 1,4-cis-hydroxyl groups. Transformation of (+)-sclareolide to III followed by a key Horner-Wadsworth-Emmons (HWE) reaction and stereospecific allylic oxidation facilitated the first synthesis of elegansin D. The biological evaluation of these natural products together with seven elegansin D analogues was performed, among which several elegansin D analogues exhibited potential anticancer activity against liver cancer HepG2 cells (IC50 = 11.99-25.58 μM) with low cytotoxicity on normal liver HL7702 cells (IC50 > 100 μM).

Comprehensive analysis of different types of ginsenosides in the different parts of American ginseng by targeted and nontargeted MS/MS scanning

To comprehensively study the ginsenosides distribution in the various tissues of American ginseng, the qualitative and quantitative-targeted and nontargeted mass spectroscopic methods were established using the high-performance liquid chromatography coupled with Qtrap triple quadrupole mass spectrometry (HPLC-QtrapQQQ-MS). The total ginsenosides of the root, stem, and leaf of American ginseng were determined by a colorimetric method, and the contents showed the order from high to low root, stem, and leaf. Eighty-two kinds of ginsenosides were detected in the different parts of American ginseng by enhanced mass scan-information-dependent data acquisition (IDA)-enhanced product ion (EPI) scan mode, including 69 from the root, 62 from the stem, and 48 from the leaf. An HPLC-multiple reaction monitoring (MRM) method was established, and 28 representative ginsenosides were further quantified in the three parts. Nearly all ginsenosides had the highest contents in the root and the lowest content in the leaf. Three types of ginsenosides (protopanaxadiol [PPD]-, protopanaxatiol [PPT]-, and oleanolic acid [OA]-types) were analyzed by precursor ion-IDA-EPI and MRM-IDA-EPI scan modes. Root had the most abundant ginsenosides in PPD- and PPT-type ginsenosides. Meanwhile, the OA-type ginsenosides are significantly enriched in the stem and leaf of American ginseng. The results provided a supplement to the quality assessment of American ginseng. PRACTICAL APPLICATION: The distribution profile of ginsenosides in the parts of American ginseng is different. Except for the root, the stem, and leaf of American ginseng have the most abundant ginsenosides in oleanolic acid type. The results reported herein can help the manufacturers choose appropriate materials to extract the ginsenosides.

Comprehensive evaluation of corrosion inhibition performance and ecotoxicological effect of cinchona IIa as a green corrosion inhibitor for pickling of Q235 steel

Here, to prevent the corrosion of Q235 steel in the pickling and discover novel green corrosion inhibitors, the corrosion inhibition performance and eco-toxicity of cinchonain IIa were evaluated. Electrochemical experiments confirms that 200 mg/L cinchonain IIa reveals good corrosion inhibition performance with 94.08% on Q235 steel in HCl for 48 h. Scanning electron microscope (SEM) and atomic force microscope (AFM) observations suggest that cinchonain IIa can be firmly attached to the metal surface by forming a barrier film. The X-ray photoelectron spectroscopy (XPS) results further verify the bonding interaction between the functional groups and the steel matrix, and indicate the existence of protective film on the steel. Meanwhile, the inhibition mechanism at the molecular/atomic level is revealed through molecular dynamics simulation. Additionally, acute toxicity test shows that cinchonain IIa is a low toxic corrosion inhibitor. Moreover, the antioxidant enzyme activity experiments confirm that cinchonain IIa discloses no obvious damage to the antioxidant system of zebrafish. Overall, cinchonain IIa exhibits low potential risks to the healthy development of aquatic organisms and ecosystems. As a proven green and low toxic corrosion inhibitor, cinchonain IIa has a sustainable application in the anti-corrosion industry.

Processing technologies, phytochemistry, bioactivities and applications of black ginseng-a novel manufactured ginseng product: A comprehensive review

Black ginseng is a novel manufactured ginseng product, and the application of black ginseng products in market is increasing in recent years. Black ginseng is prepared by steaming and fermentation, but not as mature as processing red ginseng. Therefore, complete proposals for preparation techniques are firstly presented. Additionally, there are also abundant chemical components in black ginseng, including ginsenosides, polysaccharides, amino acids, polyphenols, flavonoids, etc. Among them, ginsenosides, polysaccharides and phenolic compounds are the main ingredients, making health benefits of black ginseng stronger than other ginseng products. Therefore, black ginseng as a functional food has come to the market in various forms, such as candies, tea, porridge, soup, etc. The improvement in nutrition, flavor, and safety has exhibited a broad prospect for black ginseng products in food industry. Accordingly, preparation technologies, phytochemistry, health benefits and application of black ginseng are comprehensively evaluated.

Braille recognition by E-skin system based on binary memristive neural network

Braille system is widely used worldwide for communication by visually impaired people. However, there are still some visually impaired people who are unable to learn Braille system due to various factors, such as the age (too young or too old), brain damage, etc. A wearable and low-cost Braille recognition system may substantially help these people recognize Braille or assist them in Braille learning. In this work, we fabricated polydimethylsiloxane (PDMS)-based flexible pressure sensors to construct an electronic skin (E-skin) for the application of Braille recognition. The E-skin mimics human touch sensing function for collecting Braille information. Braille recognition is realized with a neural network based on memristors. We utilize a binary neural network algorithm with only two bias layers and three fully connected layers. Such neural network design remarkably reduces the calculation burden and, thus, the system cost. Experiments show that the system can achieve a recognition accuracy of up to 91.25%. This work demonstrates the possibility of realizing a wearable and low-cost Braille recognition system and a Braille learning-assistance system.

A concise synthesis of marine natural product (-)-15-oxopuupehenol from (+)-sclarelide

A step-economical synthesis of (-)-15-oxopuupehenol from cheap and readily available (+)-sclarelide is achieved with 20.3% overall yield in 9 steps. The key features of this synthetic mythology include a palladium catalyzed tandem carbine migratory insertion reaction to construct the key skeleton, a DDQ-mediated isomerization/oxidation of allyl alcohol to afford α, β-unsaturated ketone, and a NaOH-induced intramolecular Michael addition followed by acetonide deprotection to give (-)-15-oxopuupehenol.

Co-encapsulation of curcumin and resveratrol in zein-bovine serum albumin nanoparticles using a pH-driven method

In the present study, zein-bovine serum albumin (BSA) composite nanoparticles (NPs) are produced with the use of a pH-driven method. The mass ratio of BSA to zein has a significant impact on the particle size, but exhibits a limited effect on the surface charge. With an optimal zein/BSA weight ratio of 1 : 2, zein-BSA core-shell NPs are fabricated for the single/co-loading of curcumin and resveratrol. The incorporation of curcumin or/and resveratrol into zein-BSA NPs changes the configuration of the proteins (zein and BSA), and zein NPs transform resveratrol and curcumin from the crystalline structure to the amorphous state. Compared with resveratrol, curcumin has higher binding strength with zein BSA NPs, showing higher encapsulation efficiency and storage stability. The co-encapsulation of curcumin is found to be an effective method to improve the encapsulation efficiency and shelf-stability of resveratrol. Through this co-encapsulation technology, curcumin and resveratrol are retained in different NP regions via polarity mediation and released at different rates. The hybrid NPs formed from zein and BSA through a pH-driven method exhibit the potential of co-delivery of resveratrol and curcumin.

Total Synthesis of Marine Natural Products (+)-Strongylin A and Corallidictyal D by Regio- and Stereoselective Cyclization of Alkenyl Benzenes

An expeditious access to marine natural products (+)-strongylin A and corallidictyal D is described. A TFA/Et₃SiH-induced reductive isomerization of enols I to alkenyl benzenes II followed by a selectivity-controlled cyclization in the presence of HCl and BF₃·Et₂O affords benzofuran III and benzopyran IV, respectively. The applicability of this HCl-induced cyclization is showcased by a regio- and stereoselective synthesis of corallidictyal D, while BF₃·Et₂O-promoted cyclization posterior to rearrangement of an alkenyl benzene provides a regioselectively different benzopyran, (+)-strongylin A.

Environmentally benign cinchonain IIa from Uncaria laevigata for corrosion inhibition of Q235 steel in HCl corrosive medium: Experimental and theoretical investigation

Traditional corrosion inhibitors make great contribution to metal protection, but also cause environmental pollution. To solve the problem, plant extracts as green corrosion inhibitors have attracted much attention in recent years. Plants are good raw materials for corrosion inhibitors and also meet the requirements of industry. However, they have not been successfully applied in industry due to the unknown composition of the effective corrosion inhibitors and large dosage thereof. Therefore, cinchonain IIa was separated from Uncaria laevigata with abundant sources and low cost from nature in this work. Here we hypothesized that cinchonain IIa could show good corrosion inhibition performance for Q235 steel in the acidic medium. Through experiments and theoretical calculation, we studied the corrosion inhibition effect of cinchonain IIa on Q235 in 1 M HCl solution at 298 K for 48 h. Electrochemical experiments revealed that the inhibition efficiency of 200 mg/L cinchonain IIa in 1 M HCl for Q235 steel was 94.08% for 48 h. It even showed over 93% corrosion inhibition efficiency and durable protection performance to 28 d. Surface observations indicated that cinchonain IIa were firmly attached to the steel surface by forming a protective film. Moreover, quantum chemical calculation and molecular dynamics simulation revealed the inhibition mechanism at molecular and atomic level. Compared with some plant extracts, here we demonstrate that the outstanding advantages of cinchonain IIa include sustained protective effect, small dosage, and low toxicity. Accordingly, it may be used as a green industrial corrosion inhibitor with great potential in oilfield acidification and acid pickling.

Constraints on Sub-GeV Dark Matter-Electron Scattering from the CDEX-10 Experiment

We present improved germanium-based constraints on sub-GeV dark matter via dark matter-electron (χ-e) scattering using the 205.4  kg·day dataset from the CDEX-10 experiment. Using a novel calculation technique, we attain predicted χ-e scattering spectra observable in high-purity germanium detectors. In the heavy mediator scenario, our results achieve 3 orders of magnitude of improvement for m_{χ} larger than 80  MeV/c^{2} compared to previous germanium-based χ-e results. We also present the most stringent χ-e cross-section limit to date among experiments using solid-state detectors for m_{χ} larger than 90  MeV/c^{2} with heavy mediators and m_{χ} larger than 100  MeV/c^{2} with electric dipole coupling. The result proves the feasibility and demonstrates the vast potential of a new χ-e detection method with high-purity germanium detectors in ultralow radioactive background.

Exotic Dark Matter Search with the CDEX-10 Experiment at China's Jinping Underground Laboratory

A search for exotic dark matter (DM) in the sub-GeV mass range has been conducted using 205 kg day data taken from a p-type point contact germanium detector of the CDEX-10 experiment at China's Jinping underground laboratory. New low-mass dark matter searching channels, neutral current fermionic DM absorption (χ+A→ν+A) and DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), have been analyzed with an energy threshold of 160 eVee. No significant signal was found; thus new limits on the DM-nucleon interaction cross section are set for both models at the sub-GeV DM mass region. A cross section limit for the fermionic DM absorption is set to be 2.5×10^{-46}  cm^{2} (90% C.L.) at DM mass of 10  MeV/c^{2}. For the DM-nucleus 3→2 scattering scenario, limits are extended to DM mass of 5 and 14  MeV/c^{2} for the massless dark photon and bound DM final state, respectively.

Mesoporous crosslinked chitosan-activated clinoptilolite biocomposite for the removal of anionic and cationic dyes

A mesoporous crosslinked chitosan-activated clinoptilolite biocomposite (CS-GA/ACP) was prepared with chitosan (CS) as the substrate and glutaraldehyde (GA) as the crosslinking agent. Structural analysis of the CS-GA/ACP composite beads was performed using FTIR, SEM, and BET techniques. The adsorption properties of the CS-GA/ACP for Congo red (CR) and methylene blue (MB) removal were examined using a batch method. The effects of CS loading, CS-GA/ACP dosages (0.005-0.25 g), pH values (3-11), initial concentrations (30-300 mg/L), contact time (5-120 min), ionic strength, and temperatures (25-65 ℃) on the adsorption of CR and MB on the CS-GA/ACP composite beads were investigated. The pseudo-second-order kinetics could better describe the adsorption process than the pseudo-first-order kinetics, and the Langmuir isotherms model agreed well with the experimental data. The maximum adsorption capacities of the CS-GA/ACP for CR and MB were 180.59 mg/g and 143.67 mg/g at 25 ℃, respectively. The proposed mechanism studies showed that the possible interaction between the adsorbent and dye molecules were Yoshida H-bonding, dipole-dipole H-bonding, electrostatic interaction and n-π interaction. The CS-GA/ACP can be recycled to remove dyes without significant loss of efficacy, and the adsorption of dyes on the CS-GA/ACP is spontaneous endothermic adsorption. Overall, the CS-GA/ACP showed an excellent performance for dyes removal in aqueous solution and could be a practical candidate for industrial applications.

Immunological effect of fucosylated chondroitin sulfate and its oligomers from Holothuria fuscogilva on RAW 264.7 cells

Fucosylated chondroitin sulfate was obtained from the sea cucumber Holothuria fuscogilva (FCShf). The structure was elucidated by NMR and HILIC-FTMS analysis. FCShf contained a chondroitin core chain [→3)-β-D-GalNAc-(1 → 4)-β-D-GlcA-(1→]_n, where the sulfation positions were the O-4 or O-6 of the GalNAc residues. The ratio of sulfated and non-sulfated GalNAc at O-6 was 1:2, while the ratio of GalNAc at O-4 was 1:1. 2,4-disulfated-fucose (Fuc2,4S), 4-sulfated-fucose (Fuc4S) and 3,4-disulfated-fucose (Fuc3,4S) were attached to the O-3 of GlcA with a molar ratio of 1.00: 0.62: 1.32. The FCShf could significantly promote the proliferative rate, NO production and neutral red uptake of RAW 264.7 cells within the concentration range of 10-300 μg/mL. Compared with the fucosylation and deacetylation degrees, the molecular weight of FCShf had markedly influence on the activation of RAW 264.7 cells. A decrease in molecular weight dramatically improved the immunoregulatory activities. Furthermore, FCShf activated RAW 264.7 cells through TLR-2/4-NF-κB pathway.

Structure and hypoglycemic effect of a neutral polysaccharide isolated from sea cucumber Stichopus japonicus

In addition to its high nutritious value, sea cucumber has been recognized by folk medicine for a long time. This study investigated the structure and hyperglycemic activity of a neutral polysaccharide (NPsj) from sea cucumber Stichopus japonicus, whose molecular weight was determined as 301.75 kDa by HPGPC method. Monosaccharide composition analysis indicated that NPsj is a glucan. The structure of NPsj was obtained by combining the analysis of methylation analysis, FTIR, NMR, periodate oxidation, Smith degradation and ESI-MS, which is mainly composed of (1 → 4)-α-d-glucoses with β-d-glucose(1→) branches substituted at O-6 every 7-9 of 1,4 linked glucoses. An in vitro insulin resistance Hep G2 cells model and a 3 T3-L1 cells model were established, and the NPsj has significant effect to increase glucose consumption with no toxicity at 10-100 μg/mL. Furthermore, NPsj upregulates the phosphorylation of Akt1 and down-regulated GSK3β, and then reduces the phosphorylation of GS, indicating its mechanism of ameliorating insulin resistance via Akt/GSK3β/GS signaling pathway.

Chondroitin sulfate deposited on foxtail millet prolamin/caseinate nanoparticles to improve physicochemical properties and enhance cancer therapeutic effects

In this study, curcumin (Cur)-loaded chondroitin sulfate (CS)-sodium caseinate (NaCas)-stabilized foxtail millet prolamin (FP) composite nanoparticles (NPs) were fabricated via a one-pot process. FP is capable of self-assembly via liquid antisolvent precipitation under neutral and alkaline conditions (pH 7.0-11.0). Under this condition, the microstructures of hydrophobic FP cores, amphiphilic NaCas and hydrophilic CS shells were fabricated readily by a one-pot method. With an optimal FP/NaCas/CS weight ratio of 3 : 2 : 4, FP-NaCas-CS NPs shared globular microstructures at about 145 nm, and hydrophobic interactions, electrostatic forces, and hydrogen bonds were the main driving forces for the formation and maintenance of stable FP-NaCas-CS NPs. CS coating enhanced the pH stability but reduced the ionic strength stability. The formed NPs were stable over a wide pH range from 2.0 to 8.0 and elevated salt concentrations from 0 to 3 mol L^-1 NaCl. FP-NaCas-CS NPs exhibited a higher Cur encapsulation efficiency of 93.4% and re-dispersion capability after lyophilization. Moreover, CS coating promoted selective accumulation in CD44-overexpressing HepG2 cells, resulting in higher inhibition of tumor growth compared to free Cur and FP-NaCas NP-encapsulated Cur. As for comparison, encapsulated Cur exhibited reduced cytotoxicity on normal liver cells L-O2. This preclinical study suggests that FP-NaCas-CS NPs could be very beneficial in terms of encapsulating hydrophobic drugs, improving the effectiveness of cancer therapies and reducing side effects on normal tissues.

A specifically triggered turn-on fluorescent probe platform and its visual imaging of HClO in cells, arthritis and tumors

Understanding disease-related processes at the molecular level is of great importance for the prevention and treatment of diseases. However, due to the lack of effective analytical tools, it is challenging to gain insight into the relationships between a specific bioactive molecule and the associated disease. Herein, a rapid turn-on resorufin-based fluorescent probe platform utilizing the HClO-specific oxidative cleavage of the amide was constructed, allowing the visualization of HClO in vitro and in vivo. These probes could quickly respond to HClO (< 50 s) with high selectivity and sensitivity (12-153 nM). The probe REClO-6 had the fastest response (30 s) and the highest sensitivity (12 nM), and was successfully used for the imaging of endogenous and exogenous HClO in cells and zebrafish. Notably, it was also successfully applied to the imaging of HClO in mouse arthritis and solid tumors. This study provided a rapid imaging analysis tool, which would be used to investigate the relationship between HClO and the disease-related physiological processes.

Concise synthesis of marine natural products smenodiol and (-)-pelorol

A facile synthesis of marine natural product smenodiol has been achieved in 23.2% overall yield within 8 steps from readily available starting materials, which facilitates a concise synthesis of the marine natural product (-)-pelorol by employing a TMSOTf-mediated Friedel-Crafts reaction with a methyl ester in the aryl as the key step.

[Clinicopathological analysis and surgical strategy of primary appendiceal neoplasms]

Objective: To investigate the clinicopathological features, surgical methods and prognosis of primary appendiceal neoplasms. Methods: A descriptive case series study was performed. Clinical data of patients diagnosed with primary appendiceal neoplasms in Peking University First Hospital from 2006 to 2017 were retrospectively analyzed. Patients who underwent surgery and were confirmed as appendiceal neoplasms by postoperative pathology were included. Cases of cecal tumor invading the appendix and other organ tumors implanting in the appendix and cases of recurrent appendix tumors were excluded Pathological classification was based on the 4th edition of the WHO classification of digestive tract tumors (2010 edition), and the efficacy of operation methods of low grade appendiceal mucinous neoplasm (LAMN) were analyzed. Results: A total of 115 patients were enrolled, including 52 males and 63 females with a median age of 59 (51, 71) years. Clinical symptoms usually manifested as dormant pain in the right lower quadrant, migrating right lower abdominal pain, fever and bloating. Twenty-four cases were accidentally discovered during surgery, and 21 cases were found by physical examination. The preoperative diagnosis rate of CT and ultrasound was 40.2% (43/107) and 25.5% (24/94) respectively. The postoperative pathological types contained 83 cases of LAMN, 12 cases of mucinous adenocarcinoma, 9 cases of appendiceal neuroendocrine neoplasms (aNEN), 2 cases of mucinous adenocarcinoma with signet ring cells, 3 cases of serrated adenoma, 2 cases of goblet cell carcinoid, 2 cases of lymphoma, 1 case of leiomyoma and 1 case of schwannomas. All the patients underwent surgical resection, including 41 cases of appendectomy, 21 cases of partial cecectomy, 48 cases of right hemicolectomy, and 5 cases of combined organ resection due to appendiceal tumor infiltration or dissemination. Eighteen cases were diagnosed with pseudomyxoma peritonei (PMP) during operation. A total of 98 patients were enrolled for follow-up. The median follow-up time was 58 (5-172) months. The 5-year disease-free survival (DFS) rate was 84.5% and 5-year overall survival (OS) was 88.2%. Multivariate analysis revealed that high-grade malignancy tumors (HR=25.881, 95% CI: 2.827-236.935, P=0.004) and PMP formation (HR=42.166, 95% CI: 3.470-512.439,P=0.003) were independent risk factors for prognosis. Patients undergoing right hemicolectomy presented longer operation time, more blood loss and higher morbidity of complication as compared to those undergoing appendectomy and partial cecectomy (all P<0.05), while no significant differences in 5-year DFS (P=0.627) and 5-year OS (P=0.718) were found. Conclusions: Primary appendiceal neoplasms usually have no typical features, accompanied with low preoperative diagnosis rate. The common pathological types are LAMN, mucinous adenocarcinoma and aNEN. Appendectomy or partial cecectomy for LAMN may achieve satisfactory prognosis. High-grade malignancy tumors and PMP formation are independent risk factors for prognosis.

[Clinical analysis of 554 patients with colorectal diverticulosis]

Objective: Most patients with asymptomatic colorectal diverticulosis are easily overlooked. However, some of diverticulosis become diverticulitis, bleeding and even perforation, which cause extensive harm to patients. The purpose of this study is to analyze the incidence, clinical features, diagnosis and treatment of colorectal diverticulosis in order to improve the clinical understanding of diverticulosis and its related complications. Methods: A descriptive cohort study was carried out. Clinical data of 554 patients with colorectal diverticulosis confirmed by CT, colonoscopy, digestive tract radiography or operation in Peking University First Hospital from January 2009 to June 2019 were retrospectively analyzed. Patients with malignant tumors, autoimmune diseases, long term use of immunosuppressive drugs, chronic liver diseases and renal diseases, and mental disorders were excluded. The analysis parameters included gender, onset age, clinical symptoms, location of diverticulitis, treatment and prognosis. According to the criteria established by the World Society of Emergency Surgery (WSES), acute diverticulitis was divided into 5 stages based on the extension of the infectious process. Stage 0 was simple diverticulitis and stage 1-4 was complicated diverticulitis. Results: Among the 554 patients with colorectal diverticulosis, 358 (64.6%) were males, the median onset age was 63 years; 191 patients (34.5%) had various digestive symptoms, of whom 113 (20.4%) had chronic constipation and abdominal distension, 78 (14.1%) had chronic diarrhea and abdominal pain; the other 363 patients had no obvious abdominal symptoms. Four hundred and six patients were found by colonoscopy and 465 patients were found by CT. Twenty-five patients were diagnosed by lower gastrointestinal tract radiography and 3 were confirmed during operation. There were 339 patients with multiple diverticula (61.2%) and 215 patients with single diverticulum (38.8%). 76.5% (424/554) of diverticula were located in colon, 37.0% (205/554) in ascending colon, 21.3% (118/554) in multiple sites, and 2.2% (12/554) in rectum. The median diameter of diverticulum was 7 mm, and 78 cases (14.1%) was ≥30 mm. Forty-nine patients (8.8%) developed acute diverticulitis, including 13 patients with simple diverticulitis and 36 patients with complicated diverticulitis. Among 36 patients with complicated diverticulitis, 29 (80.6%) were males, 27 (75.0%) had recurrent abdominal pain and fever before onset; diverticula of 25 cases were located in sigmoid colon; 11 cases in ascending colon. Nine cases developed sigmoid colon perforation and 8 cases developed vesicocolonic fistula, and these 17 patients underwent surgical treatment. The other 19 cases with complicated diverticulitis developed gastrointestinal bleeding, of whom 18 cases were male, 11 cases were located in ascending colon; 13 cases were healed after conservative treatment, 4 cases received endoscopic hemostatic intervention, and 2 cases underwent surgery. Conclusions: Colorectal diverticulosis is more common in male patients, and CT and colonoscopy are main diagnostic methods. The symptoms of complicated colonic diverticulitis are related to the location of diverticulum. In addition to symptomatic treatment, surgical procedures are the most important treatments.

A modular strategy for the synthesis of marine originated meroterpenoid-type natural products

A modular strategy for meroterpenoid-type marine natural products has been developed from commercially available (+)-sclareolide using a palladium-catalyzed tandem carbene migratory insertion as one of the key steps. Its applicability is showcased by the formal synthesis of (-)-pelorol and 9-epi-pelorol and the concise total synthesis of (+)-yahazunone and (+)-yahazunol. It is worth noting that the formal synthesis of (-)-pelorol and 9-epi-pelorol was achieved by controlling the reaction sequence of hydrogenation and cyclization.

Rational design of an HClO-specific triggered self-immolative fluorescent turn-on sensor and its bioimaging applications

The development of a rapid and intuitive method for the detection of a specific small molecule biomarker is important for understanding the pathogenesis of relevant diseases. Described here is the design and evaluation of an HClO-specific triggered self-immolative fluorescent sensor (RESClO) based on the structure of an N-protected Resorufin dye. Due to the interrupted π-conjugated structure of the Resorufin dye, the free sensor showed very weak absorption and fluorescence. It can quickly complete the response to HClO (within 10 s) with high selectivity and sensitivity (LOD = 16.8 nM) in aqueous solution. The sensor can be made into test strips to quickly detect HClO in the environment by obvious changes in color and fluorescence. It was successfully used for bioimaging of exogenous and endogenous HClO in cells and zebra fish. More importantly, it can also be used for visual imaging of mouse arthritis models. Thus, sensor RESClO can provide a simple and promising visual analytical tool for the detection of HClO in the environment and the early diagnosis of HClO-mediated related diseases.

Direct conversion of sulfinamides to thiosulfonates without the use of additional redox agents under metal-free conditions

Direct conversion of sulfinamides to thiosulfonates is described. Without the use of additional redox agents, the reaction proceeds smoothly in the presence of TFA under metal-free conditions. This protocol possesses many advantages such as odourless and stable starting materials, broad substrate scope, selective synthesis, and mild reaction conditions.

[Thirty years' changes of the strategy of lateral lymph node dissection in low rectal cancer: treatment experience and prognostic analysis of 289 cases in one single center]

Objective: The surgical indications, resection extent and management principle of lateral lymph node dissection (LLND) in lower rectal cancer have been controversial between Eastern and Western countries. This study aims to provide a theoretical basis for the rational implementation of LLND by reviewing the changes of LLND strategy over the past 30 years in a single-center, and analyzing prognostic factors for the survival outcomes of patients with lateral lymph node metastasis (LLNM). Methods: A retrospective observational study was performed. Clinical data of 289 patients with rectal cancer who received LLND at the Department of General Surgery of Peking University First Hospital from 1990 to 2019 were collected. Patients were divided into three groups based on decades. There were 89 cases in 1990-1999 group, 92 cases in the 2000-2009 group, and 108 cases in the 2010-2019 group. Data analyzed: (1) patient baseline data; (2) surgery and postoperative recovery; (3) lateral lymph node dissection; (4) postoperative survival and prognosis of patients with positive lateral lymph nodes. The surgical methods and pathological results of LLND were compared between groups, and the prognostic risk factors of patients with LLNM were analyzed. Results: A total of 289 patients underwent radical resection with LLND' accounting for 6.3% of the 4542 patients with rectal cancer during the same period in our hospital. Except decade-by-decade increase in tumors with distance from anal verge ≤ 7 cm, the proportion of ulcerated tumors, and the proportion of neoadjuvant radiochemotherapy, the differences in other baseline data were not statistically significant among 3 decade groups (all P>0.05). The proportion of LLND in the 3 groups decreased decade by decade [9.9% (89/898) vs. 8.0% (92/1154) vs. 4.3% (108/2490), χ(2)=40.159, P<0.001]. The proportion of laparoscopic surgery and unilateral LLND increased, while the mean operative time, intraoperative blood loss, surgical complications above grade III and postoperative hospital stay decreased decade by decade. These 289 patients completed a total of 483 lateral dissections, including 95 cases of the unilateral dissection and 194 cases of the bilateral dissection. The proportion of LLND in the 3 groups decreased decade by decade [9.9% (89/898) vs. 8.0% (92/1154) vs. 4.3% (108/2510), P<0.001]. The median number of dissected lymph nodes in the internal iliac artery and obturator regions increased (2 vs. 3 vs. 3, P<0.001), but those in the common iliac and external iliac regions decreased significantly (4 vs. 3 vs. 2, P=0.014). A total of 71 patients with LLNM were identified. The rate of LLNM in the 2010-2019 group was significantly higher than that in the previous two groups [37.0% (40/108) vs. 16.9% (15/89) vs. 17.4% (16/92), P=0.001]. The patients with LLNM showed a poorer overall survival (OS) and disease-free survival (DFS) compared with negative lateral lymph nodes (P<0.001). There were statistically significant differences in 5-year OS rate (30.9% vs. 27.2% vs. 0, P=0.028) and 5-year DFS rate (28.3% vs. 16.0% vs. 0, P=0.038) among patients with only internal iliac lymph node metastasis, patients with only obturator lymph node metastasis, and patients with external iliac or common iliac lymph node metastasis. Multivariate analysis of prognostic factors showed that external iliac or common iliac lymph node metastasis was an independent risk factor for OS (HR=1.649, 95%CI: 1.087-2.501) and DFS (HR=1.714, 95%CI: 1.173-2.504) in patients with LLNM (all P<0.05) . The OS and DFS were not significant different in patients with LLNM among 3 decade groups. Conclusions: In the past decade, the proportion of LLND in rectal cancer has decreased significantly. However, LLNM rate has been significantly increased due to preoperative imaging assessments focusing on suspicious LLNM without compromising the survival. Internal iliac artery and obturator lymph nodes can be regarded as regional lymph nodes with a satisfactory prognosis after LLND. For suspected external iliac or common iliac lymph node metastasis, the significance of LLND remains to be further evaluated.

Corrosion resistance and antibacterial activity of procyanidin B2 as a novel environment-friendly inhibitor for Q235 steel in 1 M HCl solution

Flavonoids, alkaloids, glucosides and tannins with good corrosion inhibition are the main natural components in plants. In this work, procyanidin B2 (PCB2), a natural flavonoid, was firstly isolated from Uncaria laevigata. Corrosion inhibition, chemical reactivity and adsorption of PCB2 on Q235 carbon steel were described by experimental and theoretical studies. The inhibition performance of PCB2 as a green corrosion inhibitor was evaluated by electrochemical and gravimetric tests. The binding active sites and activities thereof on the steel surface were illustrated by quantum chemistry, and the equilibrium configuration was predicted by molecular dynamics simulation. PCB2 exhibits good corrosion inhibition on Q235 steel over a wide temperature range. The electrochemical results show that PCB2 is a mixed inhibitor, and its inhibition efficiency increases with the addition of PCB2 concentration. Moreover, the protective film is formed on the steel and the active corrosion sites are blocked significantly by surface analysis. Additionally, the theoretical calculation proves a strong interaction between PCB2 molecule and carbon steel. Besides, the antimicrobial activity was also preliminarily studied. This suggests that PCB2 exhibits better antimicrobial activity against many Gram-positive and Gram-negative bacteria. As a novel green corrosion inhibitor and antimicrobial agent, PCB2 is worthy of further exploitation.

Stress analysis of the thoracolumbar junction in the process of backward fall: An experimental study and finite element analysis

The aim of the present study was to evaluate the biomechanical mechanism of injuries of the thoracolumbar junction by the methods of a backward fall simulation experiment and finite element (FE) analysis (FEA). In the backward fall simulation experiment, one volunteer was selected to obtain the contact force data of the sacrococcygeal region during a fall. Utilizing the fall data, the FEA simulation of the backward fall process was given to the trunk FE model to obtain the stress status of local bone structures of the thoracolumbar junction during the fall process. In the fall simulation test, the sacrococcygeal region of the volunteer landed first; the total impact time was 1.14±0.58 sec, and the impact force was up to 4,056±263 N. The stress of thoracic (T)11 was as high as 42 MPa, that of the posterior margin and the junction of T11 was as high as 70.67 MPa, and that of the inferior articular process and the superior articular process was as high as 128 MPa. The average stress of T12 and the anterior margin of lumbar 1 was 25 MPa, and that of the endplate was as high as 21.7 MPa, which was mostly distributed in the back of the endplate and the surrounding cortex. According to the data obtained from the fall experiment as the loading condition of the FE model, the backward fall process can be simulated to improve the accuracy of FEA results. In the process of backward fall, the front edge of the vertebral body and the root of vertebral arch in the thoracolumbar junction are stress concentration areas, which have a greater risk of injury.

Foxtail millet prolamin as an effective encapsulant deliver curcumin by fabricating caseinate stabilized composite nanoparticles

The development of food proteins as effective delivery systems is of great significance for the encapsulation of active compounds. Foxtail millet prolamin (FP) has a high level of hydrophobic amino acids and proline, meets the basic characteristics of delivery system, and was described here for the first time as an effective delivery system for the encapsulation of curcumin. The interaction between FP and curcumin was confirmed by fluorescence spectroscopy, showing the joint driving of hydrophobic forces and hydrogen bonds. Curcumin-loaded caseinate-stabilized FP nanodispersions were prepared by anti-solvent/evaporation method. The mean particle size was about 220-235 nm, sharing features of a spherical shape, uniform particle size, and smooth surfaces. High level of curcumin was encapsulated in the FP-based nanoparticles, exhibiting high particle yield (>88.4%) and encouraging encapsulation efficiency (>71.3%). X-ray diffraction and Fourier transform infrared spectroscopy demonstrated that the encapsulated curcumin was amorphous state and interacted with proteins via non-covalent bonds. The nano-sized particles can effectively prevent the degradation of curcumin during heat treatment, and significantly enhance the antioxidant and anti-tumor properties. This study provides a new encapsulant for effective protection and targeted delivery of hydrophobic active biomolecules.

Inhibition of mild steel corrosion in 1 M HCl by chondroitin sulfate and its synergistic effect with sodium alginate

The development of effective and environment-friendly corrosion inhibitors is of great significance for the protection of mild steel in hydrochloric acid media. Accordingly, a natural polysaccharide mixture inhibitor composed of chondroitin sulfate derived from pig cartilage (CS-PC) and sodium alginate (SA) is developed here, and the synergistic effect of the two polysaccharides towards adsorption on mild steel in 1 M HCl is studied. The inhibition performance has been studied using weight loss test, electrochemical investigations, SEM, SECM and UV methods. The results indicate that the mixtures of CS-PC and SA strongly inhibit the corrosion of mild steel compared to individual inhibitors (i.e., 95.18 % versus 72.78 %), and show a synergistic inhibition effect. The structure-activity relationship between the molecular structure of the CS-PC + SA mixture and its corrosion inhibition performance has been discussed by using the quantum chemistry calculation and molecular dynamics simulations. It is believed that these results have certain guiding significance for the rational design of efficient corrosion inhibitor.

Structural elucidation and antidiabetic activity of fucosylated chondroitin sulfate from sea cucumber Stichopus japonicas

A fucosylated chondroitin sulfate was isolated from the body wall of sea cucumber Stichopus japonicus (FCSsj), whose structure was characterized by NMR spectroscopy and HILIC-FTMS. At the ratio of 1.00:0.26:0.65, three fucosyl residues were found: 2,4-disulfated-fucose (Fuc2,4S), 4-sulfated-fucose (Fuc4S) and 3,4-disulfated-fucose (Fuc3,4S), which were only linked to the O-3 of glucuronic acid residues (GlcA). Besides mono-fucosyl moieties, di-fucosyl branches, namely Fuc2,4Sα(1→3)Fuc4S, were also found to be attached to the O-3 of GlcA. The antidiabetic activity of FCSsj was evaluated using glucosamine induced insulin resistant (IR) Hep G2 cells in vitro. It was found that FCSsj significantly promoted the glucose uptake and glucose consumption of IR-Hep G2 cells in a dose-dependent manner, and could alleviate the cell damage. Furthermore, FCSsj could promote the glycogen synthesis in the glucosamine-induced IR-Hep G2 cells. These results provided a supplement for studying the antidiabetic activity of FCSsj.

Direct C2-arylation of N-acyl pyrroles with aryl halides under palladium catalysis

C2-arylation of N-acyl pyrroles with aryl halides is developed for the first time using Pd(PPh3)4 as a catalyst in combination with Ag2CO3 under air, which allowed the application of a good compatibility catalytic system. This protocol provides a straightforward method for the preparation of valuable arylated pyrroles in moderate to good yields under the standard conditions with good substrate tolerance. Interestingly, while N-benzoyl pyrroles reacted well, the use of substrates with a thiophene or furan ring indicated that the thiophene and furan rings are more reactive than pyrrole for the present catalytic system.

Switchable and efficient conversion of 2-amido-aryl oxazolines to quinazolin-4(3H)-ones and N-(2-chloroethyl)benzamides

Switchable chemoselective conversion of 2-amido-aryl oxazolines to quinazolin-4(3H)-ones or N-(2-chloroethyl)benzamides is achieved.

Synthesis of difluorinated 3-oxo-N,3-diarylpropanamides from 4-arylamino coumarins mediated by Selectfluor

An expeditious approach to synthesize difluorinated 3-oxo-N,3-diarylpropanamides from 4-arylamino coumarins has been accomplished in the presence of Selectfluor, which plays the dual role of a mild oxidant and a source of fluorine.

Adlay seed hull polysaccharide as a green corrosion inhibitor for mild steel in acid solution: surface analyses and theoretical calculations

Adlay seed hull polysaccharide was developed here as a green corrosion inhibitor for mild steel in 1 M HCl solution, and its inhibition effect was studied with electrochemical experiments, theoretical calculations, etc.