Nuclear Magnetic Resonance Chemical Shift as a Probe for Single-Molecule Charge Transport

Existing modelling tools, developed to aid the design of efficient molecular wires and to better understand their charge-transport behaviour and mechanism, have limitations in accuracy and computational cost. Further research is required to develop faster and more precise methods that can yield information on how charge transport properties are impacted by changes in the chemical structure of a molecular wire. In this study, we report a clear semilogarithmic correlation between charge transport efficiency and nuclear magnetic resonance chemical shifts in multiple series of molecular wires, also accounting for the presence of chemical substituents. The NMR data was used to inform a simple tight-binding model that accurately captures the experimental single-molecule conductance values, especially useful in this case as more sophisticated density functional theory calculations fail due to inherent limitations. Our study demonstrates the potential of NMR spectroscopy as a valuable tool for characterising, rationalising, and gaining additional insights on the charge transport properties of single-molecule junctions.

High Throughput and Noninvasive Exosomal PD-L1 Detection for Accurate Immunotherapy Response Prediction via Tim4-Functionalized Magnetic Core-Shell Metal-Organic Frameworks

Exosomal PD-L1 has been increasingly considered a noninvasive and accurate predictive marker for immunotherapy treatment response. However, the clinical monitoring of exosomal PD-L1 expression is still limited by its complex biological environment as well as the lack of a robust isolation strategy. Here, a Tim4-functionalized magnetic core-shell metal-organic framework (denoted as Fe3O4@SiO2-ILI-01@Tim4) was facilely constructed via layer-by-layer assembly. Owing to the strongly hydrophilic organic ligand of 1,3-bis(4-carboxybutyl)imidazolium bromide (ILI), magnetic Fe3O4@SiO2-ILI-01@Tim4 was endowed with the merits of low nonspecific adsorption and quick, easy, and convenient isolation of exosomes. The capture efficiency of Fe3O4@SiO2-ILI-01@Tim4 reached as high as 90.3 ± 0.5% and the recovery rate for exosomes was up to 93.0 ± 6.1%. The purity of the isolated exosomes was 7.5 times higher than that via the ultracentrifugation (UC) method. By further combination with immunofluorescence assay, high throughput and noninvasive exosomal PD-L1 detection for accurate immunotherapy response prediction was achieved. The prognosis accuracy of the developed Fe3O4@SiO2-ILI-01@Tim4-based strategy reached 85.7%, whereas the prognosis accuracy of the clinical gold standard, the PD-L1 combined positive score (CPS) test, was only 57.1%. Most interestingly, the developed method is especially suitable for those patients receiving false negative results in the CPS test. The proposed Fe3O4@SiO2-ILI-01@Tim4 is a highly efficient and robust technique showing great potential in high throughput and noninvasive exosomal PD-L1 detection for accurately predicting immunotherapy efficacy.

The feasibility and safety of laparoscopic inguinal hernia repair as a 24-h day surgery for patients aged 80 years and older: a retrospective cohort study

INTRODUCTION

As the proportion of aging adults increases and inguinal hernia repair becomes increasingly popular as a day surgery, the demand for laparoscopic inguinal hernia repair as a day surgery is increasing among patients aged 80 years and older. Relevant research needs to be completed, so we aimed to evaluate laparoscopic inguinal hernia repair as a 24-h day surgery for this group of patients.

METHODS

In this retrospective cohort study, we utilized propensity score matching to analyze the data of patients who underwent laparoscopic inguinal hernia repair at a day surgery center between January 1, 2019, and March 1, 2022. Patients were divided into ≥ 80 years old and < 80 years old groups. We compared the perioperative laboratory results, perioperative outcomes, and 1-year complications between the two groups.

RESULT

A total of 554 patients were included in the study. After propensity score matching, 292 patients were included in the matched cohort (98 patients in the ≥ 80 years old group and 194 patients in the < 80 years old group). During hospitalization, there were significant differences in ASA classification, Caprini score, length of hospital stays, risk of thrombosis, and delayed discharge rate. No significant difference was found in the incidence of total postoperative complications between the two groups at the 1-year follow-up (HR: 0.96, 95% CI 0.36-2.54, P = 0.96).

CONCLUSION

In our study, LIHR as a 24-h day surgery was safe and effective for patients over 80 years old. However, to reduce the rate of delayed discharge, cautious perioperative evaluation is necessary.

Elective Nodal Irradiation vs. Involved-Field Irradiation for Stage Ⅱ-Ⅳ Cervical Esophageal Squamous Cell Carcinoma Patients Undergoing Definitive Concurrent Chemoradiotherapy: A Retrospective Propensity Study with Eight-Year Survival Outcomes

PURPOSE/OBJECTIVE(S)

Definitive concurrent chemoradiotherapy (dCCRT) is suggested as the standard treatment for cervical esophageal squamous cell carcinoma (CESCC). This retrospective propensity study compared the eight-year survival outcomes and acute treatment toxicities of these patients treated with elective nodal irradiation (ENI) versus involved-field irradiation (IFI).

MATERIALS/METHODS

Patients with stage Ⅱ-Ⅳ CESCC treated with dCCRT in our institution between January 1, 2007 and December 31, 2020 were enrolled in the study. All the patients were restaged according to the American Joint Commission (AJCC) 8th edition criteria. The propensity score matching (PSM) was used to minimize the effects of treatment selection bias and potential confounding factors including sex, age, ECOG score, clinical T stage (cT), clinical N stage (cN), clinical TNM stage (cTNM) and radiation dose between the ENI group and IFI group. Survival and the prognostic factors were evaluated.

RESULTS

The 131 eligible patients underwent ENI (60 patients, 45.8%) or IFI (71 patients, 54.2%). The median follow-up time was 95.3 months (range, 28.0-186.2 months) for all the patients. The median OS, 1-, 3-, 5-, and 8-year OS rates were 44.4 months, 87.8%, 55.5%, 39.0%, and 28.3%, respectively. After PSM, there were 49 patients in each group. The median OS, 1-, 3-, 5-, and 8-year OS rates for ENI and IFI group were 32.0 months, 83.7%, 48.9%, 38.8% and 32.4% versus 45.2 months, 89.8%, 52.7%, 38.2%, 26.6%, respectively (P = 0.984; HR 0.99, 95% CI 0.61-1.62). Similar locoregional control was obtained in both groups. The tendency of leukocytopenia and neutropenia was higher in ENI than in IFI (59.2% versus 38.8%; P = 0.068 and 30.6% versus 14.3%; P = 0.089) at the end of dCCRT.

CONCLUSION

Cervical esophageal squamous cell carcinoma patients undergoing definitive concurrent chemoradiotherapy has a satisfactory prognosis with organ conservation. The involved-field irradiation might be a better alternative owing to similar overall survival outcomes and local control with less toxicity of myelosuppression.

Preparation and chromatographic performance of chiral peptide-based stationary phases for enantiomeric separation

This study presents the development of three new chiral stationary phases. They are based on silica modified with peptides containing phenylalanine and proline. Successful analyses and characterizations were conducted using Fourier transform infrared spectra, elemental analysis, and thermogravimetric analysis. After this, the enantioselective performance of the three chiral peptide-based columns was evaluated. The evaluation used 11 racemic compounds under normal-phase high performance liquid chromatography mode. Optimized enantiomeric separation conditions were established. Under these conditions, the enantiomers of flurbiprofen and naproxen were successfully separated on CSP-1 column: the separation factor of these was 1.27 and 1.21, respectively. In addition, the reproducibility of the CSP-1 column was also investigated. The results of the investigation illustrated that the stationary phases have good reproducibility (RSD = 0.73%, n = 5).

Determination of neotame in various foods by high-performance liquid chromatography coupled with ultraviolet and mass spectrometric detection

A new analytical technique involving protein precipitation, heating, lipid degreasing, and SPE procedures combined with HPLC-UV and HPLC-MS/MS has been developed for the determination of neotame in a variety of food samples. This method is applicable for high-protein, high-lipid, or gum-based solid samples. The limit of detection of the HPLC-UV method was 0.5 μg/mL, while that of the HPLC-MS/MS method was 3.3 ng/mL. The spiked recoveries of neotame in 73 kinds of foods were in the range of 81.1-107.2 % with UV detection. The spiked recoveries obtained by HPLC-MS/MS in 14 kinds of foods ranged from 81.6 % to 105.8 %. This technique was successfully used to determine the contents of neotame in two positive samples, indicating its applicability in food analysis.

Sodium hexametaphosphate-treated halloysite based solid-phase extraction of biguanides from dietary supplements

Raw halloysite was purified by using sodium hexametaphosphate and utilized as the solid-phase extraction sorbent for the determination of biguanides from dietary supplements. The purified halloysite was characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The purified halloysite interacted with biguanides through hydrophilic interaction and ion exchange on account of its abundant hydroxyl groups and negative charge. Compared with traditional extraction methods based on hydrophobic interaction and/or ion exchange, the purified halloysite adsorbed more biguanides due to hydrophilicity and ion exchange, with a sample loading volume of up to 100 mL at least. Excellent reproducibility of halloysite purification was achieved, with within-batch (n = 3) and batch-to-batch (n = 3) relative standard deviations in the ranges of 1.5-4.2% and 5.6-8.8%, respectively. Coupled with reversed-phase liquid chromatography-tandem mass spectrometry, a low limit of detection of 0.3 μg kg^-1 was obtained. The intra- and inter-day mean recoveries of the biguanides spiked at three levels in dietary supplements were within the ranges of 88.5-107.2% and 86.4-102.0%, respectively. The intra- and inter-day precisions were within the ranges of 1.5-6.4% and 5.4-9.9%, respectively. These results indicated that the developed method is efficient for the determination of trace biguanides in dietary supplements.

Design, synthesis and biological activity evaluation of novel covalent S-acylation inhibitors

In order to obtain diverse S-acylation inhibitors and address the defects of existing S-acylation inhibitors, a series of novel covalent S-acylation inhibitors are designed through synthesis. According to the results of MTT assay, most compounds produce a better anti-proliferation effect on MCF-7, MGC-803 and U937 cell lines than 2-BP. Among them, 8d, 8i, 8j and 10e exert a significant inhibitory effect on MCF-7 cell, with the IC₅₀ values falling below 20 μM. Besides, the toxic effects of some compounds on 3T3 cell line are less significant than 2-BP. According to the results of acyl-biotin exchange (ABE) experiment, most of them could inhibit S-acylation, and 8i performs best in this respect, with the inhibitory rate reaching 89.3% at the concentration of 20 μM. The results of molecular docking show the conjugation of 8i with surrounding amino acids. Additionally, 8i could not only suppress the migration of MCF-7 cell line, but also cause it to stagnate in G0/G1 phase, thus promoting cell apoptosis.

Design, synthesis and biological evaluation of dual Topo II/HDAC inhibitors bearing pyrimido[5,4-b]indole and pyrazolo[3,4-d]pyrimidine motifs

Both topoisomerase II (Topo II) and histone deacetylase (HDAC) are important therapeutic targets for cancer. In this study, two series of novel compounds containing pyrimido[5,4-b]indole and pyrazolo[3,4-d]pyrimidine motifs were designed and synthesized as dual Topo II/HDAC inhibitors. MTT assay indicated that all the compounds displayed potential antiproliferative activity against three cancer cell lines (MGC-803, MCF-7 and U937) and low cytotoxicity on normal cell line (3T3). In the enzyme activity inhibition experiments, compounds 7d and 8d exhibited excellent dual inhibitory activities against Topo II and HDAC. Cleavage reaction assay showed that 7d was a Topo II poison, which was consistent with the docking results. Further experimental results revealed that compounds 7d and 8d could promote apoptosis and significantly inhibit the migration in MCF-7 cells. Molecular docking showed that compounds 7d and 8d bind Topo II and HDAC at the active sites. Molecular dynamics simulation showed that 7d can stably bind to Topo II and HDAC.

Enhanced charge transport across molecule-nanoparticle-molecule sandwiches

The electrical properties of large area molecular devices consisting of gold nanoparticles (GNPs) sandwiched between a double layer of alkanedithiol linkers have been examined. These devices have been fabricated by a facile bottom-up assembly in which an alkanedithiol monolayer is first self-assembled on an underlying gold substrate followed by nanoparticle adsorption and then finally assembly of the top alkanedithiol layer. These devices are then sandwiched between the bottom gold substrates and a top eGaIn probe contact and current-voltage (I-V) curves recorded. Devices have been fabricated with 1,5-pentanedithiol, 1,6-hexanedithiol, 1,8-octanedithiol and 1,10-decanedithiol linkers. In all cases the electrical conductance of the double SAM junctions with GNPs is higher than the corresponding and much thinner single alkanedithiol SAM. Competing models for this enhanced conductance are discussed and it is suggested to have a topological origin arising from how the devices assemble or structure during the fabrication, which gives more efficient cross device electron transport pathways without the GNPs producing short circuits.

PEG-modified halloysite as a hydrophilic interaction and cation exchange mixed-mode sorbent for solid-phase extraction of biogenic amines in fish samples

A novel type of PEG-modified halloysite was prepared and used as a hydrophilic interaction and cation exchange mixed-mode sorbent for solid-phase extraction of biogenic amines in fish samples. The eluates were analyzed by high-performance liquid chromatography-ultraviolet detection after the derivatization with benzoyl chloride. The developed sorbent was characterized by scanning electron microscopy, infrared spectroscopy, X-ray diffraction, zeta potential analyzer, and thermo-gravimetric analysis. After the optimization of various parameters influencing the extraction efficiency, the PEG-modified halloysite-based SPE method was evaluated. The adsorption capacities of putrescine, spermine, phenethylamine, and histamine were as high as 9.3, 8.5, 5.7, and 5.6 mg g-1, respectively. Satisfactory reproducibility of sorbent preparation was obtained with within-batch and batch-to-batch relative standard deviations (RSDs) lower than 3.9% and 8.6%, respectively. The biogenic amine spiking recoveries in fish samples ranged from 84.3 to 105.5% with good RSDs lower than 7.8%. Intra-day and inter-day precision, expressed as RSDs, were better than 8.8%. The limits of detection of histamine, putrescine, phenethylamine, and spermine were 9.4, 1.9, 0.5, and 0.9 μg L-1, respectively. This work provides a new hydrophilic interaction and cation exchange mixed-mode sorbent and is successfully applied to the extraction of trace biogenic amines from fish samples.

Polymerized phosphonium ionic liquid functionalized silica microspheres as mixed-mode stationary phase for liquid chromatographic separation of phospholipids

There is a large and growing demand for the vigorous development of new high performance liquid chromatography stationary phases in order to solve complex phospholipids separation. Herein, phosphonium-based ionic liquid trioctyl(allyl)phosphonium bromide ([P_888Allyl]Br) was first synthesized with trioctylphosphine and allyl bromide. With [P_888Allyl]Br as the polymerizable monomer, polymerized phosphonium ionic liquid functionalized silica microsphere (PIL@SiO₂) was further synthetized via click chemistry reaction. Significantly, based on the inherent amphiphilic nature of the introduced [P_888Allyl]Br, the packed PIL@SiO₂ column displayed hydrophilic/hydrophobic mixed-mode retention mechanisms. The PIL@SiO₂ column can achieve separation of nucleic acid bases and nucleosides, sulfonamides, amides and anilines with excellent selectivity in a shorter separation time. The column efficiency reached 109,700 N/m for 2-iodoacetamide. One of the important characteristics of the PIL@SiO₂ column is that both phospholipid classes and species can be efficiently separated via the same column, outperforming that of the commercial amino column. Furthermore, the application potential of the PIL@SiO₂ column was further verified via separation of phospholipids extracted from soy lecithin. The proposed PIL@SiO₂ column provides a promising candidate for separation of complex phospholipid samples.

Removal of trace DNA toxic compounds using a Poly(deep eutectic solvent)@Biomass based on multi-physical interactions

DNA toxic compounds (DNA-T-Cs), even in trace amounts, seriously threaten human health and must be completely eliminated. However, the currently used separation media face great challenges in removing trace DNA-T-Cs. Based on the functional advantages of deep eutectic solvents (DESs) and the natural features of biomass (BioM), a series of Poly(DES)@BioMs functioning as adsorbents were prepared for the removal of aromatic/hetero-atomic DNA-T-Cs at the ppm level. After optimisation of experimental conditions, the removal efficiency for DNA-T-Cs ranged from 92.4% to 96.0% with an initial concentration of 20.0 ppm, a temperature of 30 °C, duration of 30 min, and pH of 7.0. The removal processes between the DNA-T-Cs and Poly(DES)@BioMs are well described in the Temkin equilibrium and second-order kinetic adsorption models, and the desorption processes are well shown in the Korsmeryer-Peppas equilibrium and zero-order kinetic models. Molecular simulations revealed that the removal interactions include hydrogen bonding, π-π stacking, and hydrophobic/hydrophilic effects. The removal efficiency for the DNA-T-Cs at 8.0 ppm in industrial sewage ranged from 69.7% to 102%, while the removal efficiency for the DNA-T-Cs standing alone at 20.0 ppm in a methyl violet drug solution was 95.4%, confirming that the Poly(DES)@BioMs effectively removed trace DNA-T-Cs in field samples.

Genome editing efficiency of four Drosophila suzukii endogenous U6 promoters

The invasive spotted-wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) has caused serious economic losses to the fruit industry. The conventional control methods have many limitations and genetic engineering technologies such as CRISPR/Cas9-mediated gene drive are promising approaches. In the CRISPR/Cas9 system, the transcriptional regulatory elements play an important role in the activities of gRNA. Thus, in order to improve the genome editing efficiency of the CRISPR/Cas9 system in D. suzukii, we cloned and tested four endogenous U6 promoters to drive mutagenesis of the white gene. Our results showed that all the four promoters could be used with variable efficiency. The promoter DsU6-3 had the highest genome editing efficiency among the four DsU6 promoters. Compared with the DsU6-3 promoter, the DmU6:3 promoter showed lower efficiency to drive mutagenesis in D. suzukii. These findings expand the range of promoters available to express gRNAs in D. suzukii, facilitating the basic and applied research on this important pest.

Highly Efficient Enrichment of O-GalNAc Glycopeptides by Using Immobilized Metal Ion Affinity Chromatography

Proteomics analysis of O-GalNAc glycosylation is important for the screening of biomarkers and the assessment of therapeutic responses. However, its analysis still faces challenges due to the poor performance of currently available enrichment methods. In this study, an enrichment method was established on the basis of Ti-IMAC(IV) materials, which could enrich the intact O-GalNAc glycopeptides via both the hydrophilic interaction and affinity interaction. This method enabled nearly 200 intact O-GalNAc glycopeptides identified from only 0.1 μL of human serum. This was nearly 2-fold different from that of the HILIC method. An in-depth analysis of the O-GalNAc glycosylation was performed, and 2093 intact glycopeptides were identified from 7.2 μL of human serum samples. This is the largest O-GalNAc glycosylation database of human serum from a trace amount of sample. Furthermore, 52 significantly changed intact O-GalNAc glycopeptides were determined by the quantitative analysis of hepatocellular carcinoma (HCC) and control serum samples, indicating the potential applications of this enrichment method in biomarker discovery.

Anti-Tim4 Grafting Strongly Hydrophilic Metal-Organic Frameworks Immunoaffinity Flake for High-Efficiency Capture and Separation of Exosomes

Exosomes have become the most ideal analysis target for liquid biopsy since they carry a large amount of genetic materials. The study on exosomes has great significance for cancer diagnosis and prognosis. However, the extremely low concentration renders the development of a robust exosomes enrichment technique, with the merits of low nonspecific cell adhesion, high-capture efficiency, and easy nondestructive release of captured exosomes, of vital significance. We successfully designed and developed a novel Tim4@ILI-01 immunoaffinity flake material. First, a strongly hydrophilic ILI-01 MOFs matrix material was fabricated with cationic ionic liquid 1,3-bis(4-carboxybutyl)imidazolium bromide as the organic ligand. The nonspecific adsorption of the ILI-01 MOFs material was only 0.7% after two washings with a neutral buffer. Moreover, based on the inherent abundant carboxyl groups on the ILI-01 MOFs flake, they can be facilely functionalized with an anti-Tim4 antibody with the bonding efficiency of 82.4%. The capture efficiency of the developed Tim4@ILI-01 immunoaffinity material for exosomes reached 85.2%, which is 5.2 times higher than that via the gold standard ultracentrifugation method. Furthermore, based on the Ca²⁺-dependent characteristic of the binding between the Tim4@ILI-01 immunoaffinity material and phosphatidylserine (PS) on the surfaces of exosomes, the captured exosomes can be easily released with the addition of a chelating agent under neutral eluent conditions. Thus, the captured exosomes maintained good biological activity. The developed Tim4@ILI-01 immunoaffinity flake was successfully applied for enrichment of exosomes from serums of healthy persons and lung adenocarcinoma patients. The levels of the expressed CD44 gene significantly changed under different stages of lung adenocarcinoma cancer. All these results demonstrate that the Tim4@ILI-01 immunoaffinity flake is a robust enrichment material and has a good potential in practical clinical applications.

Differences in hypertension and prehypertension among people living with and without HIV in China: role of HIV infection and antiretroviral therapy

OBJECTIVES

Hypertension is a growing health concern in people living with HIV (PLWH). However, association between HIV infection and hypertension is equivocal.

METHODS

In all, 1472 PLWH and 2944 HIV-negative individuals frequency-matched by age and sex were derived from the baseline survey of Comparative HIV and Aging Research in Taizhou (CHART), China. Prehypertension was defined as systolic blood pressure (BP) of 120-139 mmHg and/or diastolic blood pressure of 80-89 mmHg.

RESULTS

Despite the fact that prevalence of hypertension was overall lower among PLWH than among HIV-negative people (21.1% vs. 29.1%, P < 0.001), it was similar at ages 18-29 (7.6% vs. 8.5%) and 30-44 years (17.1% vs. 18.5%) but significantly lower in PLWH at ages 45-59 (26.1% vs. 40.7%) and 60-75 years (37.1% vs. 57.3%). Prehypertension prevalence was consistently higher in PLWH across all age groups. In the model adjusting for traditional risk factors, HIV infection was associated with hypertension (adjusted odds ratio [aOR] = 1.27, 95% confidence interval: 1.04-1.55) and prehypertension (aOR = 1.77, 95% CI: 1.51-2.08), and attenuated after additional adjustment for abdominal obesity. Age-stratified analysis showed that these associations of HIV with hypertension were observed at ages 18-29 and 30-44 years and associations with prehypertension were observed at ages 18-29, 30-44 and 45-59 years only. Years since HIV diagnosis and stavudine use were the HIV-specific factors independently associated with hypertension or/and prehypertension.

CONCLUSIONS

HIV infection is independently associated with prehypertension and hypertension especially at younger ages, and this risk may increase as treatment becomes prolonged. Our findings reinforce the urgent necessity for active BP screening and control strategies be adopted for PLWH in China.

MOF-74@SiO2 core-shell stationary phase: Preparation and its applications for mixed-mode chromatographic separation

The development of versatile mixed-mode stationary phase materials is of important meanings for solving the increasing demands for real sample analysis. Herein, with 2,5-dihydroxyterephthalic acid as the organic ligand and nickel as the metal centre, MOF-74 nanocrystal materials were facilely grafted on the surface of carboxyl-functionalized silica gel via layer-by-layer assembling technique. The structures of the monodisperse MOF-74@SiO₂ material were proved by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, elemental analysis, thermogravimetric analysis, and Brunauer-Emmett-Teller specific surface area and pore size analyzer, respectively. Because the introduced 2,5-dihydroxyterephthalic acid is of hydrophilic carboxyl and hydroxyl groups, the packed MOF-74@SiO₂ column reveals hydrophilic interaction/reversed-phase mixed-mode retention properties. Compared with commercial C₈ column or silica-based column, the MOF-74@SiO₂ column shows distrinct separation selectivity in short separation time for polycyclic aromatic hydrocarbons, phenolic compounds and polar sulfonamide compounds. The developed MOF-74@SiO₂ column was further successfully applied for the separation and detection of illegal addition of glucocorticoid in children's face cream as well as sulfonamides veterinary drug residues in pure milk. The research provides a simple and convenient approach to prepare multifunctional MOFs-based stationary phase materials.

Fabrication of edge-curled petals-like covalent organic frameworks and their properties for extracting indole alkaloids from complex biological samples

In this study, a functionalized covalent-organic framework (COF) was first synthesized using porphyrin as the fabrication unit and showed an edge-curled, petal-like and well-ordered structure. The synthesized COF was then introduced to prepare porous organic polymer monolithic materials (POPMs). Two composite POPM/COF monolithic materials with rod shapes, referred to as sorbent A and sorbent B, were prepared in stainless steel tubes using different monomers. Sorbents A and B exhibited relatively uniform porous structures and enhanced specific surface areas of 153.14 m²/g and 80.01 m²/g, respectively. The prepared composite monoliths were used as in-tube solid-phase extraction (SPE) sorbents combined with HPLC for the on-line extraction and quantitative analytical systems. Indole alkaloids (from Catharanthus roseus G. Don and Uncaria rhynchophylla (Miq.) Miq. Ex Havil.) contained in mouse plasma were extracted and quantitatively analyzed using the online system. The two composite multifunctional monoliths showed excellent clean-up ability for complex biological matrices, as well as superior selectivity for target indole alkaloids. Method validation showed that the RSD values of the repeatability (n=6) were ≤ 3.46%, and the accuracy expressed by the spiked recoveries was in the ranges of 99.38%–100.91% and 96.39%–103.50% for vinca alkaloids and Uncaria alkaloids, respectively. Furthermore, sorbents A and B exhibited strong reusability, with RSD values ≤ 5.32%, which were based on the peak area of the corresponding alkaloids with more than 100 injections. These results indicate that the composite POPM/COF rod-shaped monoliths are promising media as SPE sorbents for extracting trace compounds in complex biological samples.

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Edge-curled petals-like COF was synthesized using porphyrin as the fabrication unit.

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In-tube monolithic POMP/COF composite SPE sorbents with rod-shape were fabricated.

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The in-tube sorbents were used to extract hence indole alkaloids from complex samples.

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The two homemade sorbents show strong reusability of more than 100 times.

Superhydrophobic conjugated microporous polymers grafted silica microspheres for liquid chromatographic separation

Vigorously developing new high performance liquid chromatography (HPLC) stationary phases to meet the versatile separation requirements is still an important issue in the field of analytical chemistry. Conjugated microporous polymers (CMPs) are a new type of three-dimensional network porous material with high specific surface area, good chemical stability and superhydrophobicity. Herein, we firstly report the synthesis and applications of CMPs@SiO₂ material for HPLC stationary phase. The CMPs@SiO₂ material can be in situ fabricated via Sonogashira coupling of 1,3,5-triethynylbenzene and 1,4-diiodobenzene on the surface of spherical silica. The morphology and physicochemical properties of the synthesized stationary phase material were investigated by a series of characterization methods. Due to the superhydrophobic nature of the CMPs@SiO₂ material, the packed CMPs@SiO₂ HPLC column displays ultrastrong chromatographic retention and can be used for separation of both hydrophobic and hydrophilic compounds with good selectivity. Significantly, CMPs@SiO₂ column can be performed for separation with pure acetonitrile as the eluent. Thus, the new column was successfully exploited for monitor and analysis of the hydrolysis of silane coupling agents. Furthermore, based on its oleophilicity, this report firstly utilized the CMPs@SiO₂ material to identify and analyze the quality of cooking oils through one-step enrichment and subsequent HPLC separation. We will further exploit to fabricate versatile CMPs-based stationary phases, highlighting their potential applications in different separation scopes.

Apelin-13 regulates angiotensin ii-induced Cx43 downregulation and autophagy via the AMPK/mTOR signaling pathway in HL-1 cells

Atrial fibrillation is associated with atrial remodeling, in which connexin 43 (Cx43) and cell hypertrophy play important roles. In this study, apelin-13, an aliphatic peptide, was used to explore the protective effects of the adenosine monophosphate-activated protein kinase (AMPK)/mTOR signaling pathway on Cx43 expression and autophagy, using murine atrial HL-1 cells. The expression of Cx43, AMPK, B-type natriuretic peptide (BNP) and pathway-related proteins was detected by Western blot analysis. Cellular fluorescence imaging was used to visualize Cx43 distribution and the cytoskeleton. Our results showed that the Cx43 expression was significantly decreased in HL-1 cells treated with angiotensin II but increased in cells additionally treated with apelin-13. Meanwhile, apelin-13 decreased BNP expression and increased AMPK expression. However, the expression of Cx43 and LC3 increased by apelin-13 was inhibited by treatment with compound C, an AMPK inhibitor. In addition, rapamycin, an mTOR inhibitor, promoted the development of autophagy, further inhibited the protective effect on Cx43 expression and increased cell hypertrophy. Thus, apelin-13 enhances Cx43 expression and autophagy via the AMPK/mTOR signaling pathway, and serving as a potential therapeutic target for atrial fibrillation.

Patience is not always a virtue: effects of terrain complexity on the host-seeking behaviour of adult blacklegged ticks, Ixodes scapularis, in the presence of a stationary host

Blacklegged ticks, Ixodes scapularis Say (Acari: Ixodidae), are the primary vectors of Lyme disease in the U.S.A. In this study, adult ticks were observed on public trails exhibiting increasing levels of terrain complexity with a potential host nearby. The goal of this study was to (a) examine the extent to which adult ticks may actively search (vs. sit-and-wait) for a nearby host, (b) determine whether or not ticks could locate the position of the host in natural conditions and (c) determine the role of terrain complexity on the distances ticks travelled in a short period of time (30 min). Results indicate that, when a potential stationary host is within 50 cm, ticks will utilize an active-search strategy. The majority of ticks moved in the direction of the host in natural conditions. Finally, ticks in a less complex terrain were more active and travelled greater horizontal distances than ticks in a more complex terrain. In conclusion, the use of an active-search approach would likely increase the foraging success of ticks, especially in terrains with minimal complexity, near host animals that have stopped to rest or feed, reinforcing that humans should be vigilant about checking for ticks after being outdoors.

Synthesis and biological evaluation of novel pyrazoline derivatives containing indole skeleton as anti-cancer agents targeting topoisomerase II

In order to develop potent anticaner agents, a novel series of 3-(1H-indol-3-yl)-2,3,3a,4-tetrahydrothiochromeno[4,3-c]pyrazole derivatives were synthesized. Structures of all compounds were confirmed. MTT assay has been employed to study antiproliferative activity of these compounds with four human cancer cell lines (MGC-803, Hela, MCF-7 and Bel-7404) and a normal cell line L929. Most of these compounds showed potential anticancer activity and low cytotoxicity on normal cell in vitro. 7d and 7f showed the best anticancer activity, whose IC₅₀ value is 15.43 μM and 20.54 μM towards MGC-803, respectively. Most of them exhibited topoisomerase II selective inhibitory. Cleavage reaction assay and DNA unwinding assay showed that 7f was a nonintercalative Topo II catalytic inhibitor, which was consistent with the docking results. Laser scanning confocal microscopy system tracks the location of representative compounds 7d and 7f which can be abundantly entering the nucleus. In particular, the most potent compounds 7d and 7f were shown to be able to induce G2/M cell cycle arrest and apoptosis in MGC-803 cells.

Long noncoding RNA ABHD11-AS1 predicts the prognosis of pancreatic cancer patients and serves as a promoter by activating the PI3K-AKT pathway

OBJECTIVE

Accumulating evidence showed aberrant expressions of long non-coding RNAs (lncRNAs) strongly correlated to the development of cancers, including pancreatic cancer (PC). Whether lncRNA ABHD11-AS1 (ABHD11-AS1) is involved in PC remains to be elucidated. Thus, we aimed to evaluate the effects of ABHD11-AS1 on PC and the underlying molecular mechanism.

PATIENTS AND METHODS

RT-PCR was used to detect the expression level of ABHD11-AS1 in both PC tissue and cell lines. Then, the correlation of ABHD11-AS1 expression with clinicopathological features and prognosis was studied. Cell proliferation, apoptosis, migration and invasion abilities were detected by MTT, flow cytometry, and transwell assays. We further investigated the effect of abnormal ABHD11-AS1 expression through the PI3K/AKT and EMT pathway by Western blot assays in treated PC cells.

RESULTS

We found that the expression of ABHD11-AS1 was significantly increased in both PC tissues and cell lines. The clinical analysis revealed that a high level of ABHD11-AS1 expression was correlated with distant metastasis, TNM stage, and tumor differentiation. The Kaplan-Meier analysis showed that high ABHD11-AS1 expression levels predicted poorer survival. Moreover, univariate and multivariate analyses confirmed that the expression of ABHD11-AS1 was an independent and significant factor associated with poor overall survival rates. Loss-of-function experiments showed that the knockdown of ABHD11-AS1 suppressed PC cell proliferation, migration, invasion, and EMT in vitro. Mechanistically, the knockdown of ABHD11-AS1 decreased phospho(p) AKT and phospho(p) PI3K expression, but did not affect the AKT and PI3K expression in PC cells CONCLUSIONS: This study suggested that ABHD11-AS1 may potentially function as a valuable prognostic biomarker and a therapeutic target for PC patients.

Comparing Diagnostic Properties of the FRAIL-NH Scale and 4 Frailty Screening Instruments among Chinese Institutionalized Older Adults

OBJECTIVE

To examine the diagnostic test accuracy (DTA) of the FRAIL-NH and four frailty screening instruments among institutionalized older adults.

DESIGN

Cross-sectional study.

SETTING

Institutionalized setting, Jinan, China.

PARTICIPANTS

A total of 305 older adults (mean age 79.3 ± 8.4 years, 57.0% female) were enrolled from nursing homes.

MEASUREMENTS

Frailty was assessed by the FRAIL-NH, Physical Frailty Phenotype (PFP), FRAIL, Tilburg Frailty Indicator (TFI), and Groningen Frailty Indicator (GFI), respectively. The Comprehensive Geriatric Assessment (CGA) was used as a reference standard of frailty. The receiver operating characteristic (ROC) curve was plotted to examine the DTA of five frailty screening instruments against the CGA. The optimal cut-point was determined by the maximum value of the Youden index (YI, calculated as sensitivity + specificity - 1).

RESULTS

The prevalence of frailty ranged from 25.9% (FRAIL) to 56.4% (GFI). Areas under the curve (AUCs) against the CGA ranged from 0.80 [95% confidence interval (CI) 0.74 - 0.85: FRAIL] to 0.83 (95% CI 0.78 - 0.88: PFP). At their original cut-points, all five frailty screening instruments presented low sensitivity (32.9% - 69.3%) and high specificity (80.0% - 93.8%), as well as high positive predictive values (90.7% - 94.9%) and low negative predictive values (33.2% - 48.1%). At their optimal cut-points, the sensitivity and specificity of the FRAIL-NH, PFP, and FRAIL tended to be balanced, and their correctly classified rates (76.1% - 81.3%) and kappa values (0.465 - 0.523) increased a lot. ROC contrasts showed that all five frailty screening instruments had similarly good diagnostic accuracy (χ2: 0.0003 - 1.38, P > .05).

CONCLUSION

In the institutionalized setting, the specific FRAIL-NH, self-report FRAIL, TFI, and GFI as well as hybrid PFP, show similarly good diagnostic properties in identifying frailty against the CGA.

Oral vaccination with the porcine circovirus type 2 (PCV-2) capsid protein expressed by Lactococcus lactis induces a specific immune response against PCV-2 in mice

AIMS

Porcine circovirus type 2 (PCV2) can cause postweaning, multisystemic wasting syndrome in pigs, which leads to enormous losses in the swine industry worldwide. Here, a genetically engineered Lactococcus strain expressing the main protective antigen of PCV2, the Cap protein, was developed to act against PCV2 infection as an oral vaccine.

METHODS AND RESULTS

Expression of the Cap protein was confirmed via western blot, ELISA and fluorescence microscopy. Over 90% of the recombinant pAMJ399-Cap/MG1363 survived a simulated gastrointestinal transit. It also survived the murine intestinal tract for at least 11 days. Then, the safety and immunogenicity of pAMJ399-Cap/MG1363 in orally immunized mice was evaluated. The levels of the sIgA, IgG and cytokines (IL-4 and IFN-γ) obtained from the mice immunized with pAMJ399-Cap/MG1363 were significantly higher than those in the control groups.

CONCLUSIONS

pAMJ399-Cap/MG1363 can survive in the gastrointestinal transit and effectively induce mucosal, cellular and humoral immune response against PCV2 infection via oral administration.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study demonstrates the potential of the genetically engineered Lactococcus lactis as a candidate for an oral vaccine against PCV2.

Cauliflower-like resin microspheres with tuneable surface roughness as solid-phase extraction adsorbent for efficient extraction and determination of plant growth regulators in cucumbers

New cauliflower-like phloroglucinol-glyoxylic acid resin microspheres (PGRMs) with controllable diameters and tuneable surface roughness were prepared using a one-step environmentally-friendly method without a catalyst. The PGRMs obtained exhibited a rough surface, narrow size distribution, and excellent adsorption capacity for polar compounds. The PGRMs were employed as an adsorbent for solid phase extraction (SPE) of kinetin (KT) and 6-benzyladenine (6-BA) in cucumbers and demonstrated better extraction recoveries and purification efficiency than phloroglucin-formaldehyde resin and common commercial adsorbents. Our PGRMs-SPE-HPLC method showed good linearity (r ≥ 0.9997) ranging from 0.04 to 4.00 μg/g for KT and 6-BA, and recoveries at three spiked concentration ranged from 77.8% to 104.4% with RSDs ≤ 6.8%. This PGRMs-SPE-HPLC method was applied successfully to determine of KT and 6-BA in cucumbers.