Determination of moxifloxacin in milk using a ratiometric fluorescent sensor based on Ag-MOF@curcumin.

Moxifloxacin (MFX) has attracted increasing public concern recently, and the development of a simple and effective analysis method has become a research focus. In this work, a simple, sensitive and ratiometric fluorescent sensor based on Ag-MOF@curcumin was designed and investigated. Ag-MOF@curcumin displays emission at 410 nm and 475 nm under excitation at 330 nm. When MFX is added, a new emission peak appears at 500 nm, and the F500/F410 ratio has a linear relationship with the MFX concentration in the range 0-35 µmol L-1 with a low LOD (0.179 µmol L-1). Finally, the developed sensor was used for the determination of MFX in milk. This work provides an excellent fluorescent sensor for highly selective and rapid detection of MFX residues.

Silver nanoparticles coated cellulose-based flexible membrane with excellent UV resistance, high infrared reflection and water resistance for personal thermal management.

Designing of a green and multifunctionally integrated cellulose-based flexible wearable material with personal thermoregulation, water and ultraviolet (UV) resistance is essential for the development of personal thermal management and smart textiles. Herein, a hydrophobic silver nanoparticles cellulose-based membrane (H-AgNPs/CEPCM) was prepared through simple solution blending, spin-coating process and chemical vapor modification. The prepared membrane exhibited excellent UV resistance due to the synergistic effect of carbon quantum dots (CQDs) as well as UV-absorbing functional groups. The spin-coated AgNPs layer with high infrared reflectivity has great radiant insulation, and temperature was reduced by 3.4 °C compared with H-CEPCM in indoor environment. Furthermore, the mechanical properties of H-AgNPs/CEPCM were significantly improved by the introduction of amide and ether bonds, as well as a large number of hydrogen bonds. This led to a tensile strength of 23.21 MPa and an elongation at break of 16.57 %, while also providing water resistance. Additionally, the H-AgNPs/CEPCM exhibited outstanding thermal stability and hydrophobicity. This work may provide a feasible and promising strategy for the construction of multifunctional integrated cellulose membrane materials for radiant insulation, outdoor textiles and novel UV protection applications.

Selection of regioselective DNA aptamer for detection of homocysteine in nondeproteinized human plasma.

Small molecule-binding aptamers often suffer from high cross reactivity to structure analogues in biological samples, limiting their value for clinical diagnosis. Herein, we present a method to overcome this issue, by performing binding-inhibited organic reaction-based regioselective selection of aptamers against homocysteine (Hcy), which is a marker for diagnosing many disorders including stroke and Alzheimer's. This approach has led to isolation of a DNA aptamer that binds to the alkane thiol chain of Hcy with exceptional specificity against cysteine. It also binds with oxidized Hcy at weaker affinity. Using this new aptamer, we produced a reusable fluorescent optical fiber aptasensor for direct and validated detection of both free and total Hcy in nondeproteinized patient plasma in the diagnostic concentration range. The binding site-specific aptamer selection and optical-fiber-sensing strategy can expand the practical utility of aptamers in clinical diagnosis.

Light-mediated anthocyanin biosynthesis in rose petals involves a balanced regulatory module comprising transcription factors RhHY5, RhMYB114a, and RhMYB3b.

Roses are significant botanical species with both ornamental and economic value, displaying diverse floral traits, particularly an extensive array of petal colors. The red pigmentation of rose petals is predominantly attributed to anthocyanin accumulation. However, the underlying regulatory mechanism of anthocyanin biosynthesis in roses remains elusive. This study presents a novel light-responsive regulatory module governing anthocyanin biosynthesis in rose petals, which involves the transcription factors RhHY5, RhMYB114a, and RhMYB3b. Under light conditions (1000-1500 µmol m-2 s-1), RhHY5 represses RhMYB3b expression and induces RhMYB114a expression, positively regulating anthocyanin biosynthesis in rose petals. Notably, activation of anthocyanin structural genes probably involves an interaction and synergy between RhHY5 and the MYB114a-bHLH3-WD40 complex. Additionally, RhMYB3b is activated by RhMYB114a to prevent excessive accumulation of anthocyanin. Conversely, under low light conditions (<10 µmol m-2 s-1), the degradation of RhHY5 leads to down-regulation of RhMYB114a and up-regulation of RhMYB3b, which in turn inhibits the expression of both RhMYB114a and anthocyanin structural genes. Additionally, RhMYB3b competes with RhMYB114a for binding to RhbHLH3 and the promoters of anthocyanin-related structural genes. Overall, our study uncovers a complex light-mediated regulatory network that governs anthocyanin biosynthesis in rose petals, providing new insights into the molecular mechanisms underlying petal color formation in rose.

Lower dose of metformin combined with artesunate induced autophagy-dependent apoptosis of glioblastoma by activating ROS-AMPK-mTOR axis.

Glioblastoma multiform (GBM), one of the most common, aggressive primary brain tumours, demonstrates resistance to radiotherapy and chemotherapy after surgical resection and treatment failure. Metformin (MET) has been shown to suppress the proliferative capacity and invasion ability of GBM cells by activating AMPK and inhibiting mTOR, but the effective dose exceeded the maximum tolerated dose. Artesunate (ART) can exert certain anti-tumour effects by activating the AMPK-mTOR axis and inducing autophagy in tumour cells. Therefore, this study investigated the effects of MET combined with ART combination therapy on autophagy and apoptosis in GBM cells. MET combined with ART treatment effectively suppressed the viability, mono-cloning ability, migration and invasion capacities, as well as metastatic ability of GBM cells. The underlying mechanism involved modulation of the ROS-AMPK-mTOR axis, which was confirmed using 3-methyladenine and rapamycin to inhibit or promote the effects of MET combined with ART, respectively. The study findings suggest that MET used in combination with ART can induce autophagy-dependent apoptosis in GBM cells by activating the ROS-AMPK-mTOR pathway, providing a potential new treatment for GBM.

Development and Validation of a Modified QuEChERS Method for Simultaneous Analysis of 250 Flavor Constituents in Tobacco by Gas Chromatography Tandem Mass Spectrometry.

BACKGROUND: Flavor constituents play an important role in the flavor characteristics of tobacco leaves and cigarettes. Sensitive, selective, and high-throughput multi-analyte analytical methods are needed to satisfy the demand for analyzing trace-level flavor constituents in tobacco. However, trace analysis of multi-targets in a complex tobacco matrix is significantly challenging. OBJECTIVE: This study was undertaken to develop and validate a fast, selective, sensitive, and accurate GC-tandem mass spectrometry (GC-MS/MS) method for the simultaneous analysis of 250 flavor constituents in tobacco using a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction procedure and backflushing technique. METHODS: The samples were extracted with a mixture of acetonitrile and phosphate buffer. GC-MS/MS served as a reliable tool to quantify the flavor constituents due to its high sensitivity, selectivity, and good repeatability. RESULTS: Our evaluation showed that 243 flavor constituents presented good linearity. Average recoveries of 216 target compounds in tobacco ranged from 70 to 120% with RSDs less than 20% at three fortification levels. The limits of quantitation of 225 and 25 compounds were in the range of 2-50 and 51-112 µg/kg, respectively. This method was then successfully applied to the analysis of 15 commercial cigarette samples with different style characteristics. CONCLUSION: The modified QuEChERS method worked very well for a wide range of flavor constituents that have not been reported by QuEChERS pretreatment previously, and the use of concurrent backflushing offered significant increase in system robustness and sample throughput. The method greatly improved the detection performance and the range of the flavor constituents, and proved to be more accurate, sensitive, selective, convenient, and practical than the reported method, and thus, can be applied in routine analysis. HIGHLIGHTS: A validated QuEChERS-based GC-MS/MS method for multiple flavor constituents analysis in tobacco was reported for the first time. The use of concurrent backflushing markedly improved the instrument robustness and sample throughput.

Ultrasensitive evanescent wave optical fiber aptasensor for online, continuous, type-specific detection of sulfonamides in environmental water.

Sensors capable for online continuous monitoring of total sulfonamides in environmental waters are highly desired due to their adverse effects on ecosystem, unexpected concentration fluctuation, and diversity. At present, no sensor with this capability has been reported. In this study, we evaluated the cross reactivity (CR) of the previously reported sulfadimethoxine-binding aptamer using DNase I assay and found that the aptamer was type-specific to sulfonamides. We then fabricated the first type-specific sulfonamide sensor, where the aptamer was immobilized on the optical fiber of the evanescent wave sensor, followed by the surface coating with Tween 80. The competitive binding of sulfonamides and Cy5.5 labeled complementary DNA enabled the low femtomolar to picomolar sensitivity and the detection of total 14 sulfonamides spiked in the lake water. The sensor also exhibited high selectivity, regeneration capability (40 cycles), stability (65 days), and short detection time (5 min). In addition, we found that the CRs were greatly dependent on the buffer composition. By performing the parallel detections in two buffers, the sensors detected 18 out of the 24 sulfonamides with the diversity coverage higher than commercial ELISA kits. Our aptasensor fills the technical gap for continuous monitoring of total sulfonamides in environmental waters.

Thiazolidinedione-Based Structure Modification of Celastrol Provides Thiazolidinedione-Conjugated Derivatives as Potent Agents against Non-Small-Cell Lung Cancer Cells through a Mitochondria-Mediated Apoptotic Pathway.

In order to improve the potential of celastrol against non-small-cell lung cancer cells, the privileged structure, thiazolidinedione, was introduced into its C-20 carboxylic group with acetylpiperazine as a linker, and the thiazolidinedione-conjugated compounds 10a-10t were prepared. The target compounds were evaluated for their cytotoxic activities against the A549 cell line, and the results showed that most of the compounds 10a-10t displayed improved potency over celastrol, and compound 10b exhibited significant activity against the A549 cell line, with an IC50 value of 0.08 µM, which was 13.8-fold more potent than celastrol (IC50 = 1.10 µM). The mechanistic studies suggested that 10b could induce A549 cell apoptosis, as evidenced by Hoechst 33342 staining and annexin V-FITC/propidium iodide dual staining assays. Western blot analysis suggested that compound 10b could upregulate Bax expression, downregulate Bcl-2 expression, and activate the mitochondria-mediated apoptotic pathway. Furthermore, compound 10b could effectively inhibit tumor growth when tested in an A549 cell xenograft mouse model. Collectively, compound 10b is worthy of further investigation to support the discovery of effective agents against non-small-cell lung cancer.

Discovery of a Colon-Targeted Azo Prodrug of Tofacitinib through the Establishment of Colon-Specific Delivery Systems Constructed by 5-ASA-PABA-MAC and 5-ASA-PABA-Diamine for the Treatment of Ulcerative Colitis.

To mitigate the systemic adverse effects of tofacitinib, 5-ASA-PABA-MAC and 5-ASA-PABA-diamine colon-specific delivery systems were constructed, and tofacitinib azo prodrugs 9 and 20a-20g were synthesized accordingly. The release studies suggested that these systems could effectively release tofacitinib in vitro, and the 5-ASA-PABA-diamine system could successfully realize the colon targeting of tofacitinib in vivo. Specifically, compound 20g displayed a 3.67-fold decrease of plasma AUC(tofacitinib, 0-∞) and a 9.61-fold increase of colonic AUC(tofacitinib, 0-12h), compared with tofacitinib at a molar equivalent oral dose. Moreover, mouse models suggested that compound 20g (1.5 mg/kg) could achieve roughly the same efficacy against ulcerative colitis compared with tofacitinib (10 mg/kg) and did not impair natural killer cells. These results demonstrated the feasibility of compound 20g as an effective alternative to mitigate the systemic adverse effects of tofacitinib, and 5-ASA-PABA-MAC and 5-ASA-PABA-diamine systems were proven to be effective for colon-specific drug delivery.

Scaffold hopping of celastrol provides derivatives containing pepper ring, pyrazine and oxazole substructures as potent autophagy inducers against breast cancer cell line MCF-7.

Three series of celastrol derivatives, namely, 6a-6i, 11a-11i and 15a-15i, were designed based on the scaffold hopping strategy. The derivatives were synthesized and biologically evaluated against five human tumor cell lines (i.e. A549, MCF-7, Bel7402, HT-29 and PC3) using MTT assay in vitro. Results showed that compound 11i exhibited apparent antiproliferative activity against the MCF-7 cell line with an IC50 value of 1.31 µM and could remarkably inhibit the colony formation of the MCF-7 cells. Transmission electron microscopy assay, monodansylcadaverine incorporation assay and the expression of LC3 A/B, p62 and Beclin-1 in MCF-7 cells suggested that the potent antiproliferative activity of compound 11i was mainly due to its autophagy-inducing effect. Moreover, compound 11i could arrest the MCF-7 cells in the G2/M phase by regulating the cell-cycle-related proteins Cdk-1 and Cyclin B1. In the zebrafish xenograft model, compound 11i could obviously inhibit the proliferation of the MCF-7 cells. Thus, compound 11i could serve as a promising lead compound for breast cancer therapy.

Formation of chlorinated halobenzoquinones during chlorination of free aromatic amino acids.

Chlorinated halobenzoquinones (HBQs) widely exist in drinking water as emerging disinfection byproducts (DBPs), which have attracted significant attention due to their wide occurrence and high toxicity. In this study, the formation of chlorinated HBQs from the three free aromatic amino acids, tryptophan (Trp), tyrosine (Tyr) and phenylalanine (Phe), during chlorination was investigated, the formation pathways of chlorinated HBQs were explained based on the detected intermediates and influence factors. The results revealed that four chlorinated HBQs, including 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ), 2,3,5-trichloro-1,4-benzoquinone, 2,3,5,6-tetrachloro-1,4-benzoquinone and 2,6-dichloro-3-methyl-1,4-benzonquinone, were formed in chlorination of the three free aromatic amino acids, and 2,6-DCBQ was the dominant species among the formed chlorinated HBQs. Of the three free aromatic amino acids, Trp and Tyr presented relatively high yields of chlorinated HBQs than Phe. Moreover, ten intermediates were successfully detected (e.g., N,2-dichloroaniline from Trp, 2,4,6-trichlorophenol from Tyr) according to the isotope and fragment information obtained using high resolution mass spectrometry. The formation pathways of chlorinated HBQs from Trp and Tyr were proposed to include electrophilic addition, electrophilic substitution, oxidation, deacidification and dehydration reaction, and further validated using theoretical calculation. The yields of chlorinated HBQs during chlorination of the free aromatic amino acids were significantly affected by free chlorine dosage, pH and temperature.

Cell-Based Ambient Venturi Autosampling and Matrix-Assisted Laser Desorption Ionization Mass Spectrometric Imaging of Secretory Products.

A cell-based ambient Venturi autosampling device was established for the monitoring of dynamic cell secretions in response to chemical stimulations in real time with temporal resolution on the order of a second. Detection of secretory products of cells and screening of bioactive compounds are primarily performed on an ambient autosampling probe and matrix-assisted laser desorption ionization (MALDI) mass spectrometry. It takes advantage of the Venturi effect in which the fluid flowing through an inlet capillary tube is automatically fed into a parallel array of multiple outlet capillaries. Cells are incubated inside the inlet capillary tube that is connected with either a syringe pump or liquid chromatography (LC) for the transfer of single compounds or mixtures, respectively. Secretory products were continuously pushed into the outlet capillaries and then spotted into a compressed thin film of the matrix material 9-aminoacridine for MALDI mass spectrometric imaging. In physiological pH, without the use of high voltages and without the use of chemical derivatizations, this platform can be applied to the direct assay of neurotransmitters or other secretory products released from cells in response to the stimulation of individual compounds or LC-separated eluates of natural mixtures. It provides a new way to identify bioactive compounds with a detection limit down to 0.04 fmol/pixel.

Intramolecular hydrogen bond interruption and scaffold hopping of TMC-5 led to 2-(4-alkoxy-3-cyanophenyl)pyrimidine-4/5-carboxylic acids and 6-(4-alkoxy-3-cyanophenyl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-ones as potent pyrimidine-based xanthine oxidase inhibitors.

Many pyrimidine-based xanthine oxidase (XO) inhibitors with diverse chemotypes have been reported recently. Our previous study revealed that 2-(4-alkoxy-3-cyano)phenyl-6-imino-1,6-dihydropyrimidine-5-carboxylic acid derivatives exhibited remarkable XO inhibitory potency. Notably, an intramolecular hydrogen bond (IMHB) formed between amino and carboxylic groups could be observed. With the hope to expand the structure-activity relationships (SARs) and obtain potential pyrimidine-based XO inhibitors, IMHB interruption and scaffold hopping were carried out on these compounds to design 2-(4-alkoxy-3-cyanophenyl)pyrimidine-4/5-carboxylic acids (11a-11n and 15a-15j) and 6-(4-alkoxy-3-cyanophenyl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-ones (19a-19j). Among them, compound 19a (IC50 = 0.039 µM) was identified as the most promising compound with substantially higher in vitro inhibitory potency than allopurinol (IC50 = 7.590 µM) and comparable to febuxostat (IC50 = 0.028 µM). The SAR analysis revealed that interrupting the IMHB through the removal of the amino group could damage the XO inhibitory potency; pyrimidine-4-carboxylic acid moiety was more beneficial for the XO inhibitory potency than the pyrimidine-5-carboxylic acid moiety. Additionally, enzyme kinetics studies suggested that compounds 11a, 15a and 19a acted as mixed-type inhibitors for XO and the removal of 6-position amino group resulted in a weakened affinity to the free enzyme, but an enhanced binding to the enzyme-substrate complex. Molecular modeling provided a reasonable explanation for the SARs observed in this study. Furthermore, in vivo hypouricemic effects demonstrated that compounds 15a and 19a could effectively reduce serum uric acid levels at an oral dose of 10 mg/kg, with 19a demonstrating a stronger effect than 15a. Therefore, our study proved that 6-(4-alkoxy-3-cyanophenyl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-ones were potent pyrimidine-based XO inhibitors and compound 19a required further structural optimization as a potential and efficacious agents for the treatment of hyperuricemia and gout.

Synthesis and biological evaluation of celastrol derivatives as potential anti-glioma agents by activating RIP1/RIP3/MLKL pathway to induce necroptosis.

Celastrol, a quinone methide triterpenoid, possesses potential anti-glioma activity. However, its relatively low activity limit its application as an effective agent for glioma treatment. In search for effective anti-glioma agents, this work designed and synthesized two series of celastrol C-3 OH and C-20 COOH derivatives 4a-4o and 6a-6o containing 1, 2, 3-triazole moiety. Their anti-glioma activities against four human glioma cell lines (A172, LN229, U87, and U251) were then evaluated using MTT assay in vitro. Results showed that compound 6i (IC50 = 0.94 µM) exhibited substantial antiproliferative activity against U251 cell line, that was 4.7-fold more potent than that of celastrol (IC50 = 4.43 µM). In addition, compound 6i remarkably inhibited the colony formation and migration of U251 cells. Further transmission electron microscopy and mitochondrial depolarization assays in U251 cells indicated that the potent anti-glioma activity of 6i was attributed to necroptosis. Mechanism investigation revealed that compound 6i induced necroptosis mainly by activating the RIP1/RIP3/MLKL pathway. Additionally, compound 6i exerted acceptable BBB permeability in mice and inhibited U251 cell proliferation in an in vivo zebrafish xenograft model, obviously. In summary, compound 6i might be a promising lead compound for potent celastrol derivatives as anti-glioma agents.

A Soft Evaporation and Ionization Technique for Mass Spectrometric Analysis and Bio-Imaging of Metal Ions in Plants Based on Metal-Iodide Cluster Ionization.

Protonation/deprotonation is the well-recognized mass spectrometric mechanism in matrix-assisted laser desorption ionization of organic molecules but not for metal ions with different oxidation states. We describe herein a soft evaporation and ionization technique for metal ions based on iodination/de-iodination in metal-iodide cluster ionization (MICI). It is not only able to determine identities and oxidation states of metal ions but also reveal spatial distributions and isotope ratios in response to physiological or environmental changes. A long chain alcohol 1-tetradecanol with no functional groups that can absorb laser irradiation was used to cover and prevent samples from direct laser ablation. Upon the irradiation of the third harmonic Nd3+:YAG (355 nm, 3 ns), iohexol containing three covalently bonded iodine atoms instantly generates negative iodide ions that can quantitatively form clusters with at least 14 essential metal ions present in plants. The detection limits vary with different metal ions down to low fmol. MICI eliminates the atomization process that obscures metal charges in inductively coupled plasma mass spectrometry. Because only metal ions can be iodinated with iohexol, interferences from the abundant organic molecules of plants that are confronted by secondary ion mass spectrometry (SIMS) are also greatly decreased.

A highly specific aptamer probe targeting PD-L1 in tumor tissue sections: Mutation favors specificity.

Although DNA aptamers can show comparable affinity to antibodies and have the advantage of having high batch-to-batch consistency, they often suffer from unsatisfied specificity for complex samples. The limited library size used for aptamer in vitro isolation (SELEX) has been recognized as one of the major reasons. Programmed cell death-ligand 1 (PD-L1) is both a key protein in cancer diagnostics and also immunotherapy. We report here a DNA aptamer that highly specifically binds PD-L1 expressed on the surface of various cancer cells and multiple types of tissue sections. The aptamers were selected from a DNA library containing a type II restriction endonuclease Alu I recognition site in the middle of the 40-nt random sequences, against recombinant PD-L1 rather than the whole cell or tissue section. The library enrichment was achieved by Alu I mediated-SELEX, named as REase-SELEX, in which Alu I cut off the non-binders at the recognition site and, more importantly, induced library mutations to substantially increase the library diversity. 8-60, a representative aptamer with high affinity (KD = 1.4 nM determined by SPR) successfully detected four types of cancer cells with PD-L1 expression levels from low to high by flow cytometry, normal human tonsil (gold standard for PD-L1 antibody evaluation), clinical non-small cell lung cancer (high PD-L1 expression level), and malignant melanoma (low PD-L1 expression level) tissue sections by fluorescence microscopy imaging, showing unprecedented high specificity. The results demonstrate that 8-60 is an advanced probe for PD-L1 cancer diagnostics and mutations in SELEX greatly favor aptamer specificity.

Synthesis and biological evaluation of 2-(4-alkoxy-3-cyano)phenylpyrimidine derivatives with 4-amino or 4-hydroxy as a pharmacophore element binding with xanthine oxidase active site.

Xanthine oxidase is the rate-limiting enzyme critical for the synthesis of uric acid, and therefore xanthine oxidase inhibitors are considered as one of the promising therapies for hyperuricemia and gout. In our previous study, series of 2-(4-alkoxy-3-cyano)phenyl-6-oxo-1,6-dihydropyrimidine-5-carboxylic acids and 2-(4-alkoxy-3-cyano)phenyl-6-imino-1,6-dihydropyrimidine-5-carboxylic acids were synthesized that presented excellent in vitro xanthine oxidase inhibitory potency. Interestingly, molecular docking studies revealed that the interaction behavior of these compounds with xanthine oxidase was changed after the conversion from a hydroxy group to amine group. To further investigate the structure-activity relationships of these pyrimidine-containing xanthine oxidase inhibitors and explore the contribution of amino or hydroxy group on xanthine oxidase inhibitory potency, several 2-phenylpyrimidine derivatives with amino or hydroxy functional group were designed and synthesized. Thereafter, the structure-activity research and molecular modeling study proved that hydroxy and amino groups could be used as pharmacophore elements for the design of 2-phenylpyrimidines xanthine oxidase inhibitors. Particularly, the optimized compound, 2-(3-cyano-4-isopentoxy)phenylpyrimidine-4-ol, emerged the strongest xanthine oxidase inhibitor potency, with an IC50 value of 0.046 µM, which was approximately 120-fold more potent than that of allopurinol (IC50 = 5.462 µM). Additionally, Lineweaver-Burk plot analysis revealed that the optimized compound acted as a mixed-type inhibitor. Furthermore, the in vivo hypouricemic effect of the optimized compound was investigated in a hyperuricemia rat model induced by potassium oxonate, and the results showed that the optimized compound could effectively reduce serum uric acid levels at an oral dose of 30 mg/kg.

Alternations in the liver metabolome, skin and serum antioxidant function of silver pomfret (Pampus Argenteus) is induced by jellyfish feeding.

Many fish species are known to feed on jellyfish. Herein, we observed the effects of jellyfish feeding on silver pomfret using gas chromatography tandem time-of-flight mass spectrometry (GC-TOF-MS) based on metabolomics. We studied the effects of feeding on jellyfish on skin and serum immune of silver pomfret. Healthy silver pomfret (initial weight, 13.40 ± 1.565 g) was divided into two groups: control and feeding. The pomfrets were fed jellyfish at 2, 6, 12, 24, and 72 h, and samples were obtained. Statistical analysis revealed that after jellyfish feeding, most serum immune indicators did not show a significant change; however, skin immune indicators indicated that silver pomfret elicit a stress response on encountering jellyfish, gradually adapting to their presence. We therefore conducted further experiments involving two groups: group A, which was not fed any extra jellyfish, and group B, which was fed extra jellyfish (approximately 10% weight of silver pomfret) every day for 60 days. Orthogonal partial least squares discriminant analysis led to the identification of stronger biomarkers, with the liver metabolome showing obvious variations between the groups (group B vs. A). After feeding jellyfish by silver pomfret, some amino acids, amines, and unsaturated fatty acids in the liver tissue showed a significant increase. Our results, thus, not only reveal changes in physiological indices of silver pomfret after feeding on jellyfish but also provide a new idea for further optimizing the feed formula for silver pomfret culture.

HER2 transmembrane domain mutation: comprehensive characteristics and real-world evidence of treatment response in Chinese lung adenocarcinoma.

BACKGROUND: HER2 transmembrane domain (TMD) mutation has been reported as a rare driver mutation associated with advanced stage disease and a poor prognosis in patients with lung adenocarcinoma (LUAD). We aimed to comprehensively profile the genetic landscape and treatment response information of HER2 TMD-mutant LUAD. METHODS: An in-house database of 7,812 LUAD patients was screened for mutation prevalence. A multi-center cohort of 16 HER2 V659E-mutant patients and an external cohort of 38 HER2-mutant patients from cBioPortal with overall survival (OS) data were analyzed. Eight patients from the in-house cohort were included in the real-world study of treatment response. Molecular docking simulation and binding affinity prediction were performed. RESULTS: In Chinese LUAD, the prevalence of HER2 TMD mutation was 0.18% (14/7,812), and 0.14% (11/7,812) for the HER2 V659E mutation. The most recurrent co-alteration was TP53 mutation (n=4, 25%) and HER2 amplification (n=2, 12.5%). TMD-mutant patients were diagnosed at more advance stages (P<0.001) and had poorer OS (median OS 10.0 vs. 61.6 months, HR =7.9, 95% CI: 1.0-61.0, P<0.001) than non-TMD mutations. The overall response rate of targeted therapy, chemo-based therapy, and immunotherapy was 57.1%, 22.2%, and 0%, respectively. We postulated to challenge the resistance of tyrosine kinase inhibitor (TKI) with another with stronger binding energy to HER2 and supported the conclusion with a successful case. Additionally, we demonstrated a three-month response to the off-label use of pyrotinib in fifth-line therapy. CONCLUSIONS: Comapred with non-TMD mtuations, HER2 TMD mutation is a rare driver mutation with poorer prognosis in LUAD. Targeted therapy is the dominant choice for patients harboring this targetable mutation and longer OS could possibly be achieved through rechallenge with TKI of stronger binding affinity. Response to fifth-line pyrotinib was observed.

PD-L1 aptamer isolation via Modular-SELEX and its applications in cancer cell detection and tumor tissue section imaging.

PD-1/PD-L1 is an important pathway in immunotherapy and a high PD-L1 expression level in tumor tissues is an essential prerequisite for PD-1/PD-L1 blocking-based therapy. The PD-L1 expression level in tumor tissue sections is currently detected via immunohistochemistry (IHC) using anti-PD-L1 antibodies from various resources, which has the disadvantage of inconsistent results. As synthetic affinity ligands, aptamers have good batch-to-batch consistency and have been demonstrated to have great potential for use in biomedical applications. In this study, we isolated PD-L1 aptamers using a combination method, named Modular-SELEX (systematic evolution of ligands by exponential enrichment), which includes three sequentially performed modules: the affinity module, the specificity module, and the compatibility module. Three rounds of magnetic crosslinking precipitation (MCP)-SELEX, three rounds of Capture-SELEX, and two rounds of Tissue-SELEX were respectively performed in the corresponding three modules to significantly and efficiently improve the native affinity, specificity, and compatibility of the enriched library. The isolated aptamer Clon-3 had nanomolar binding affinity, as determined via both homogeneous and PD-L1 immobilized affinity assays. Clon-3 could be used to recognize various cancer cells with distinct PD-L1 expression levels using flow cytometry. The PD-L1 expression levels in normal human tonsils (the gold standard for anti-PD-L1 antibody) and non-small cell lung cancer tissue sections stained using Cy5.5-labeled Clon-3 were also successfully imaged using a confocal microscope. The fluorescence intensities of the tissue sections were in good agreement with their actual PD-L1 expression levels as confirmed via IHC.