An engineered Pichia pastoris platform for the biosynthesis of silk-based nanomaterials with therapeutic potential.

Silk fibroin (SF) from the cocoon of silkworm has exceptional mechanical properties and biocompatibility and is used as a biomaterial in a variety of fields. Sustainable, affordable, and scalable manufacturing of SF would enable its large-scale use. We report for the first time the high-level secretory production of recombinant SF peptides in engineered Pichia pastoris cell factories and the processing thereof to nanomaterials. Two SF peptides (BmSPR3 and BmSPR4) were synthesized and secreted by P. pastoris using signal peptides and appropriate spacing between hydrophilic sequences. By strain engineering to reduce protein degradation, increase glycyl-tRNA supply, and improve protein secretion, we created the optimized P. pastoris chassis PPGSP-8 to produce BmSPR3 and BmSPR4. The SF fed-batch fermentation titers of the resulting two P. pastoris cell factories were 11.39 and 9.48 g/L, respectively. Protein self-assembly was inhibited by adding Tween 80 to the medium. Recombinant SF peptides were processed to nanoparticles (NPs) and nanofibrils. The physicochemical properties of nanoparticles R3NPs and R4NPs from the recombinant SFs synthesized in P. pastoris cell factories were similar or superior to those of RSFNPs (Regenerated Silk Fibroin NanoParticles) originating from commercially available SF. Our work will facilitate the production by microbial fermentation of functional SF for use as a biomaterial.

Sinomenine attenuates pulmonary fibrosis by downregulating TGF-ß1/Smad3, PI3K/Akt and NF-κB signaling pathways.

BACKGROUND: Since COVID-19 became a global epidemic disease in 2019, pulmonary fibrosis (PF) has become more prevalent among persons with severe infections, with IPF being the most prevalent form. In traditional Chinese medicine, various disorders are treated using Sinomenine (SIN). The SIN's strategy for PF defense is unclear. METHODS: Bleomycin (BLM) was used to induce PF, after which inflammatory factors, lung histological alterations, and the TGF-/Smad signaling pathway were assessed. By administering various dosages of SIN and the TGF- receptor inhibitor SB-431,542 to human embryonic lung fibroblasts (HFL-1) and A549 cells, we were able to examine proliferation and migration as well as the signaling molecules implicated in Epithelial-Mesenchymal Transition (EMT) and Extra-Cellular Matrix (ECM). RESULTS: In vivo, SIN reduced the pathological changes in the lung tissue induced by BLM, reduced the abnormal expression of inflammatory cytokines, and improved the weight and survival rate of mice. In vitro, SIN inhibited the migration and proliferation by inhibiting TGF-ß1/Smad3, PI3K/Akt, and NF-κB pathways, prevented the myofibroblasts (FMT) of HFL-1, reversed the EMT of A549 cells, restored the balance of matrix metalloenzymes, and reduced the expression of ECM proteins. CONCLUSION: SIN attenuated PF by down-regulating TGF-ß/Smad3, PI3K/Akt, and NF-κB signaling pathways, being a potential effective drug in the treatment of PF.

Central venous-to-arterial carbon dioxide partial pressure difference as a guiding parameter for cardiotonic drug administration in patients with early-stage septic shock.

OBJECTIVE: This study aimed to investigate the effect of the central venous-to-arterial carbon dioxide partial pressure difference (Pcv-aCO2) on the administration of cardiotonic drugs in patients with early-stage septic shock. METHODS: A retrospective study was conducted on 120 patients suffering from septic shock. At admission, the left ventricular ejection fraction (LVEF) and Pcv-aCO2 of the patients were obtained. On the premise of mean arterial pressure (MAP) ≥ 65 mmHg, the patients were divided into two groups according to the treatment approaches adopted by different doctors-Control group: LVEF ≤50%; Observation group: Pcv-aCO2 ≥ 6. Both groups received cardiotonic therapy. RESULTS: The two groups of patients had similar general conditions and pre-resuscitation conditions (P > 0.05). Compared to the Control group, the Observation group had a higher MAP, Lac clearance rate, and urine output after six hours of resuscitation (P < 0.05), but a lower absolute value of Lac, total fluid intake in 24 hours, and a lower number of patients receiving renal replacement therapy during hospitalization (P < 0.05). After six hours of resuscitation, the percentages of patients meeting central venous oxygen saturation and central venous pressure targets were not significantly different between the Control and Observation groups (P > 0.05). There was no difference in the 28-day mortality rate between the two groups (P > 0.05). CONCLUSION: Pcv-aCO2 is more effective than LVEF in guiding the administration of cardiotonic drugs in the treatment of patients with septic shock.

A highly selective dual-signal response ratiometric fluorescence sensing strategy for malachite green in fish based on carbon dots/copper nanoclusters nanocomposite.

Malachite green (MG), a widely used antiparasitic agent, poses health risks to human due to its genotoxic and carcinogenic properties. Herein, a stable dual-emission fluoroprobe of carbon dots/copper nanoclusters is prepared for highly selective detection of MG based on the inner filter effect. This probe exhibits characteristic emission bands at 435 and 625 nm when excited at 376 nm. After adding MG, the both emission signals were significantly quenched, and the ratio of fluorescence intensity (F435/F625) was linearly related to the concentration of MG in the range of 0.05-40 µmol L-1 with a limit of detection of 18.2 nmol L-1. Meanwhile, the two signals exhibit linear relationships with the concentration of MG, respectively, and the corresponding detection results were consistent. The fluoroprobe was successfully used for the detection of MG in fish samples with the recoveries ranging from 96.0% to 103.8% and a relative standard deviation of <3.3%.

[Clinical and Mechanism Research Progress in Amelioration of Mild Cognitive Impairment via Meditation].

Mild cognitive impairment(MCI)has a high risk of progressing to dementia,with no recommended therapies.Recent studies have shown that meditation has huge potential to improve the cognitive function,with low cost and high safety,being suitable to be applied in the treatment of neurological and psychotic disorders.This paper reviews the application and prospects of meditation in treating MCI from the concept,clinical efficacy,and mechanism of meditation,aiming to provide reference for future clinical studies.

Impact of transcranial electrical stimulation on serum neurotrophic factors and language function in patients with speech disorders.

BACKGROUND: Speech disorders have a substantial impact on communication abilities and quality of life. Traditional treatments such as speech and psychological therapies frequently demonstrate limited effectiveness and patient compliance. Transcranial electrical stimulation (TES) has emerged as a promising non-invasive treatment to improve neurological functions. However, its effectiveness in enhancing language functions and serum neurofactor levels in individuals with speech disorders requires further investigation. AIM: To investigate the impact of TES in conjunction with standard therapies on serum neurotrophic factor levels and language function in patients with speech disorders. METHODS: In a controlled study spanning from March 2019 to November 2021, 81 patients with speech disorders were divided into a control group (n = 40) receiving standard speech stimulation and psychological intervention, and an observation group (n = 41) receiving additional TES. The study assessed serum levels of ciliary neurotrophic factor (CNTF), glial cell-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), and nerve growth factor (NGF), as well as evaluations of motor function, language function, and development quotient scores. RESULTS: After 3 wk of intervention, the observation group exhibited significantly higher serum levels of CNTF, GDNF, BDNF, and NGF compared to the control group. Moreover, improvements were noted in motor function, cognitive function, language skills, physical abilities, and overall development quotient scores. It is worth mentioning that the observation group also displayed superior performance in language-specific tasks such as writing, reading comprehension, retelling, and fluency. CONCLUSION: This retrospective study concluded that TES combined with traditional speech and psychotherapy can effectively increase the levels of neurokines in the blood and enhance language function in patients with speech disorders. These results provide a promising avenue for integrating TES into standard treatment methods for speech disorders.

The requirement of the mitochondrial protein NDUFS8 for angiogenesis.

Mitochondria are important for the activation of endothelial cells and the process of angiogenesis. NDUFS8 (NADH:ubiquinone oxidoreductase core subunit S8) is a protein that plays a critical role in the function of mitochondrial Complex I. We aimed to investigate the potential involvement of NDUFS8 in angiogenesis. In human umbilical vein endothelial cells (HUVECs) and other endothelial cell types, we employed viral shRNA to silence NDUFS8 or employed the CRISPR/Cas9 method to knockout (KO) it, resulting in impaired mitochondrial functions in the endothelial cells, causing reduction in mitochondrial oxygen consumption and Complex I activity, decreased ATP production, mitochondrial depolarization, increased oxidative stress and reactive oxygen species (ROS) production, and enhanced lipid oxidation. Significantly, NDUFS8 silencing or KO hindered cell proliferation, migration, and capillary tube formation in cultured endothelial cells. In addition, there was a moderate increase in apoptosis within NDUFS8-depleted endothelial cells. Conversely, ectopic overexpression of NDUFS8 demonstrated a pro-angiogenic impact, enhancing cell proliferation, migration, and capillary tube formation in HUVECs and other endothelial cells. NDUFS8 is pivotal for Akt-mTOR cascade activation in endothelial cells. Depleting NDUFS8 inhibited Akt-mTOR activation, reversible with exogenous ATP in HUVECs. Conversely, NDUFS8 overexpression boosted Akt-mTOR activation. Furthermore, the inhibitory effects of NDUFS8 knockdown on cell proliferation, migration, and capillary tube formation were rescued by Akt re-activation via a constitutively-active Akt1. In vivo experiments using an endothelial-specific NDUFS8 shRNA adeno-associated virus (AAV), administered via intravitreous injection, revealed that endothelial knockdown of NDUFS8 inhibited retinal angiogenesis. ATP reduction, oxidative stress, and enhanced lipid oxidation were detected in mouse retinal tissues with endothelial knockdown of NDUFS8. Lastly, we observed an increase in NDUFS8 expression in retinal proliferative membrane tissues obtained from human patients with proliferative diabetic retinopathy. Our findings underscore the essential role of the mitochondrial protein NDUFS8 in regulating endothelial cell activation and angiogenesis.

Increased miR-3074-5p expression promotes M1 polarization and pyroptosis of macrophages via ERα/NLRP3 pathway and induces adverse pregnancy outcomes in mice.

Decidual macrophages (dMϕs) play critical roles in regulation of immune-microhomeostasis at maternal-fetal interface during pregnancy, but the underlying molecular mechanisms are still unclear. In this study, it was found that litter size and fetal weight were significantly reduced, whereas the rate of embryo resorption was increased in miR-3074-5p knock-in (3074-KI) pregnant mice, compared to that of wild-type (WT) pregnant mice. Plasma levels of pro-inflammatory cytokines in 3074-KI pregnant mice were also significantly elevated compared to WT pregnant mice at GD7.5. The quantity of M1-Mϕs in uterine tissues of 3074-KI pregnant mice was significantly increased compared to WT pregnant mice at GD13.5. Estrogen receptor-α (ERα) was validated to be a target of miR-3074-5p. Either miR-3074-5p overexpression or ERα knockdown promoted transcriptional activity of NF-κB/p65, induced M1-polarization and pyroptosis of THP1-derived Mϕs, accompanied with increased intracellular levels of cleaved Caspase-1, cleaved IL-1ß, NLRP3, cleaved GSDMD and ASC aggregation. Furthermore, ERα could not only bind to NLRP3 or ASC directly, but also inhibit the interaction between NLRP3 and ASC. The endometrial miR-3074-5p expression level at the middle secretory stage of repeated implantation failure (RIF) patients was significantly decreased compared to that of control fertile women. These data indicated that miR-3074-5p could promote M1 polarization and pyroptosis of Mϕs via activation of NLRP3 inflammasome by targeting ERα, and the dysregulation of miR-3074-5p expression in dMϕs might damage the embryo implantation and placentation by interfering with inflammatory microenvironment at the maternal-fetal interface during early pregnancy.

Formulation of arginine-loaded mesoporous silica nanoparticles (Arg@MSNs) modified orthodontic adhesive.

OBJECTIVES: The objective of this study was to synthesize arginine loaded mesoporous silica nanoparticles (Arg@MSNs), develop a novel orthodontic adhesive using Arg@MSNs as modifiers, and investigate the adhesive performance, antibacterial activity, and biocompatibility. METHODS: Arg@MSNs were synthesized by immobilizing arginine into MSNs and characterized using transmission electron microscope (TEM), dynamic light scattering (DLS), and Fourier Transform Infrared Spectrometer (FT-IR). Arg@MSNs were incorporated into Transbond XT adhesive with different mass fraction to form functional adhesives. The degree of conversion (DC), arginine release behavior, adhesive performance, antibacterial activity against Streptococcus mutans biofilm, and cytotoxicity were comprehensively evaluated. RESULTS: TEM, DLS, and FT-IR characterizations confirmed the successful preparation of Arg@MSNs. The incorporation of Arg@MSNs did not significantly affect DC and exhibited clinically acceptable bonding strength. Compared to the commercial control, the Arg@MSNs modified adhesives greatly suppressed the metabolic activity and polysaccharide production while increased the biofilm pH values. The cell counting kit (CCK)-8 test indicated no cytotoxicity. CONCLUSIONS: The novel orthodontic adhesive containing Arg@MSNs exhibited significantly enhanced antibacterial activities and inhibitory effects on acid production compared to the commercial adhesive without compromising their bonding strength or biocompatibility. CLINICAL SIGNIFICANCE: The novel orthodontic adhesive containing Arg@MSNs exhibits potential clinical benefits in preventing demineralization of enamel surfaces around or beneath orthodontic brackets due to its enhanced antibacterial activities and acid-producing inhibitory effects.

The Orbicularis Oculi Muscle Sparing Full-Incision Double-Eyelid Blepharoplasty.

BACKGROUND: Double-eyelid blepharoplasty was the most prevailing cosmetic procedures in China. To reduce the visible scar and unnatural crease after the removal of the OOM in the traditional full-incision double-eyelid technique. This research tried to introduce and promote the orbicularis oculi muscle sparing full-incision double-eyelid blepharoplasty with more conservative resection of upper eyelid soft tissue. METHODS: The orbicularis oculi muscle sparing full-incision double-eyelid blepharoplasty was operated and evaluated in 227 patients (454 eyes), and the esthetic results, the satisfaction of patients and complications were scored and analyzed at 6-12 months postoperative. RESULTS: Of the 227 patient, 164 (72.25%) patients were very satisfied, and 49 (21.59%) patients were satisfied, 14 (6.17%) patients were unsatisfied mainly because of the loss of palpebral fold or shallow folds. The average subjective scar score was 4.92 with 209 (92.1%) patients scored very satisfied, 18 patients scored satisfied. No patients experienced the eyelid numbness, dry eyes, and stitch abscess. 8 patients (3.52%) developed mild eye irritation in early postoperative period, however the symptoms resolved spontaneously in 2 weeks. CONCLUSION: The orbiculars oculi muscle sparing full-incision double-eyelid blepharoplasty contributes to the conservation of the physiology of the eyelid structure, producing a reliable, nature, dynamic double-eyelid crease with a light scar and less complication. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Sex differences in the association of the uric acid to high-density lipoprotein cholesterol ratio with coronary artery disease risk among Chinese nondialysis patients with CKD stages 3-5.

BACKGROUND AND AIMS: Evidence has indicated that serum uric acid (UA) and high-density lipoprotein cholesterol (HDL-C) are positively and negatively associated with coronary artery disease (CAD). The UA to HDL-C ratio (UHR) has recently drawn attention as a new predictor for metabolic syndrome, inflammation and atherosclerosis. However, the association between the UHR and CAD in nondialysis chronic kidney disease (CKD) patients is still unclear. METHODS AND RESULTS: We retrospectively analysed 733 733 nondialysis patients with CKD stage 3-5 who received their first coronary artery angiography (CAG), including 510 participants with CAD. All laboratory indicators were collected within one week before CAG. The median UHR of CAD and non-CAD patients was 15.52% and 12.29%, respectively. In multivariate analysis, female patients with a high UHR were 4.7 times more at risk of CAD than those with a lower UHR. Meanwhile, the positive association of the UHR with the severity of coronary artery stenosis (CAS) persisted significantly in female CAD subjects but not in males. In addition, receiver operating characteristic (ROC) curves were constructed for CAD and severe CAS. The area under the curve (AUC) for the UHR was higher than that for UA and HDL-C alone in female patients [UHR (AUC): 0.715 for CAD and 0.716 for severe CAS]. CONCLUSIONS: An elevated UHR was independently related to an increased CAD risk and the severity of CAS in nondialysis female patients with CKD stage 3-5, and was more predictive of the onset of CAD and the severity of CAS than UA or HDL-C alone.

Advances in Pediatric Toe Transfers.

Microsurgery is undoubtedly the pinnacle of hand surgery. Significant advancement in recent years has stretched the indications for toe-to-hand transfer in both acquired and congenital hand defects to restore function, esthetics, and motion, with minimal morbidity to the donor site. There is no one fixed microsurgical transfer technique but a surgeon's versatility and innovation in using what one could spare because each case is unique. Esthetic refinements and reducing donor site morbidities have taken a front seat in recent years. We present a few cases to put forward the senior author's preferred techniques with this objective in mind.

Microwave-assisted esterification and electro-enhanced solid-phase microextraction of omega-3 polyunsaturated fatty acids in eggs.

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs), a type of fatty acid that has many health benefits, are of increasing concern. Herein, we developed a method for the rapid esterification and enrichment of ω-3 PUFAs in eggs, which includes microwave-assisted esterification (MAE) and electrically enhanced solid-phase microextraction (EE-SPME). Combined with gas chromatographic, efficient detection of ω-3 PUFAs was achieved in eggs. Under microwave radiation, the esterification efficiency exhibited a significant increase ranging from 5.06 to 10.65 times. The EE-SPME method reduced extraction time from 50 to 15 min. In addition, improvements in extractive fiber coating materials were explored, which ensured efficient extraction of ω-3 PUFAs. Under the optimal conditions, the method displayed a low detection limit (1.01-1.54 µg L-1), good recoveries (85.82%-106.01%), and wide linear range (7.5-1000 µg L-1), which was successfully applied to determine ω-3 PUFAs in real egg samples.

TBK1, a prioritized drug repurposing target for amyotrophic lateral sclerosis: evidence from druggable genome Mendelian randomization and pharmacological verification in vitro.

BACKGROUND: There is a lack of effective therapeutic strategies for amyotrophic lateral sclerosis (ALS); therefore, drug repurposing might provide a rapid approach to meet the urgent need for treatment. METHODS: To identify therapeutic targets associated with ALS, we conducted Mendelian randomization (MR) analysis and colocalization analysis using cis-eQTL of druggable gene and ALS GWAS data collections to determine annotated druggable gene targets that exhibited significant associations with ALS. By subsequent repurposing drug discovery coupled with inclusion criteria selection, we identified several drug candidates corresponding to their druggable gene targets that have been genetically validated. The pharmacological assays were then conducted to further assess the efficacy of genetics-supported repurposed drugs for potential ALS therapy in various cellular models. RESULTS: Through MR analysis, we identified potential ALS druggable genes in the blood, including TBK1 [OR 1.30, 95%CI (1.19, 1.42)], TNFSF12 [OR 1.36, 95%CI (1.19, 1.56)], GPX3 [OR 1.28, 95%CI (1.15, 1.43)], TNFSF13 [OR 0.45, 95%CI (0.32, 0.64)], and CD68 [OR 0.38, 95%CI (0.24, 0.58)]. Additionally, we identified potential ALS druggable genes in the brain, including RESP18 [OR 1.11, 95%CI (1.07, 1.16)], GPX3 [OR 0.57, 95%CI (0.48, 0.68)], GDF9 [OR 0.77, 95%CI (0.67, 0.88)], and PTPRN [OR 0.17, 95%CI (0.08, 0.34)]. Among them, TBK1, TNFSF12, RESP18, and GPX3 were confirmed in further colocalization analysis. We identified five drugs with repurposing opportunities targeting TBK1, TNFSF12, and GPX3, namely fostamatinib (R788), amlexanox (AMX), BIIB-023, RG-7212, and glutathione as potential repurposing drugs. R788 and AMX were prioritized due to their genetic supports, safety profiles, and cost-effectiveness evaluation. Further pharmacological analysis revealed that R788 and AMX mitigated neuroinflammation in ALS cell models characterized by overly active cGAS/STING signaling that was induced by MSA-2 or ALS-related toxic proteins (TDP-43 and SOD1), through the inhibition of TBK1 phosphorylation. CONCLUSIONS: Our MR analyses provided genetic evidence supporting TBK1, TNFSF12, RESP18, and GPX3 as druggable genes for ALS treatment. Among the drug candidates targeting the above genes with repurposing opportunities, FDA-approved drug-R788 and AMX served as effective TBK1 inhibitors. The subsequent pharmacological studies validated the potential of R788 and AMX for treating specific ALS subtypes through the inhibition of TBK1 phosphorylation.

TRIM59-mediated ferroptosis enhances neuroblastoma development and chemosensitivity through p53 ubiquitination and degradation.

Neuroblastoma, predominantly afflicting young individuals, is characterized as an embryonal tumor, with poor prognosis primarily attributed to chemoresistance. This study delved into the impact of tripartite motif (TRIM) 59, an E3 ligase, on neuroblastoma development and chemosensitivity through mediating ferroptosis and the involvement of the tumor suppressor p53. Clinical samples were assessed for TRIM59 and p53 levels to explore their correlation with neuroblastoma differentiation. In neuroblastoma cells, modulation of TRIM59 expression, either through overexpression or knockdown, was coupled with doxorubicin hydrochloride (DOX) or ferrostatin-1 (Fer-1) therapy. In vivo assessments examined the influence of TRIM59 knockdown on neuroblastoma chemosensitivity to DOX. Co-immunoprecipitation and ubiquitination assays investigated the association between TRIM59 and p53. Proliferation was gauged with Cell Counting Kit-8, lipid reactive oxygen species (ROS) were assessed via flow cytometry, and protein levels were determined by Western blotting. TRIM59 expression was inversely correlated with neuroblastoma differentiation and positively linked to cell proliferation in response to DOX. Moreover, TRIM59 impeded lipid ROS generation and ferroptosis by directly interacting with p53, promoting its ubiquitination and degradation in DOX-exposed neuroblastoma cells. Fer-1 countered the impact of TRIM59 knockdown on neuroblastoma, while TRIM59 knockdown enhanced the therapeutic efficacy of DOX in xenograph mice. This study underscores TRIM59 as an oncogene in neuroblastoma, fostering growth and chemoresistance by suppressing ferroptosis through p53 ubiquitination and degradation. TRIM59 emerges as a potential strategy for neuroblastoma therapy.

Targeted Bacterial Keratitis Treatment with Polyethylene Glycol-Dithiothreitol- Boric Acid Hydrogel and Gatifloxacin.

OBJECTIVE: To prolong the ocular residence time of gatifloxacin and enhance its efficacy against bacterial keratitis, this study developed a velocity-controlled polyethylene glycol-dithiothreitol- boric acid (PDB) hydrogel loaded with gatifloxacin. MATERIALS AND METHODS: First, the basic properties of the synthesized PDB hydrogel and the gatifloxacin- loaded PDB hydrogel were assessed. Secondly, the in vitro degradation rate of the drugloaded PDB was measured in a simulated body fluid environment with pH 7.4/5.5. The release behavior of the drug-loaded PDB was studied using a dialysis method with PBS solution of pH 7.4/5.5 as the release medium. Finally, a mouse model of bacterial keratitis was established, and tissue morphology was observed using hematoxylin-eosin staining. Additionally, mouse tear fluid was extracted to observe the antibacterial effect of the gatifloxacin-loaded PDB hydrogel. RESULTS: The results showed that the PDB hydrogel had a particle size of 124.9 nm and a zeta potential of -23.3 mV, with good porosity, thermosensitivity, viscosity distribution, rheological properties, and high cell compatibility. The encapsulation of gatifloxacin did not alter the physical properties of the PDB hydrogel and maintained appropriate swelling and stability, with a high drug release rate in acidic conditions. Furthermore, animal experiments demonstrated that the gatifloxacin- loaded PDB hydrogel exhibited superior therapeutic effects compared to gatifloxacin eye drops and displayed strong antibacterial capabilities against bacterial keratitis. CONCLUSION: This study successfully synthesized PDB hydrogel and developed a gatifloxacin drug release system. The hydrogel exhibited good thermosensitivity, pH responsiveness, stability, and excellent biocompatibility, which can enhance drug retention, utilization, and therapeutic effects on the ocular surface.

Covalent organic framework reinforced hollow fiber bar for extraction and detection of bisphenols from beverages.

Bisphenols (BPs) can migrate from packaging materials into foods, resulting in potentially harmful residues. For example, accumulation of BPs is associated with endocrine disorders. Owing to matrix effects, development of an effective and eco-friendly sample pretreatment would be helpful for BPs detection in beverages packed in plastic containers. In this work, an extraction bar, composed of hollow fiber (HF) functionalized with covalent organic frameworks (COF@Tp-NDA) and 1-ocanol, was prepared for extraction of five BPs simultaneously. The synergistic effect of COF@Tp-NDA and 1-octanol improved the extraction efficiency of BPs from milk-based beverage, juice, and tea beverage. Under optimal conditions, limits of detection ranged from 0.10 to 2.00 ng mL-1 (R2 ≥ 0.9974) and recoveries ranged from 70.1 % to 106.8 %. This method has the potential to enrich BPs, supporting their accurate determination in complex beverages.

[Cloning and functional analysis of flavanone synthase â ¡ from Dendrobium huoshanense].

Flavonoid C-glycosides are a class of natural products that are widely involved in plant defense responses and have diverse pharmacological activities. They are also important active ingredients of Dendrobium huoshanense. Flavanone synthase Ⅱ has been proven to be a key enzyme in the synthesis pathway of flavonoid C-glycosides in plants, and their catalytic product 2-hydroxyflavanone is the precursor compound for the synthesis of various reported flavonoid C-glycosides. In this study, based on the reported amino acid sequence of flavanone synthase Ⅱ, a flavanone synthase Ⅱ gene(DhuFNSⅡ) was screened and verified from the constructed D. huoshanense genome localization database. Functional validation of the enzyme showed that it could in vitro catalyze naringenin and pinocembrin to produce apigenin and chrysin, respectively. The open reading frame(ORF) of DhuFNSⅡ was 1 644 bp in length, encoding 547 amino acids. Subcellular localization showed that the protein was localized on the endoplasmic reticulum. RT-qPCR results showed that DhuFNSⅡ had the highest expression in stems, followed by leaves and roots. The expression levels of DhuFNSⅡ and other target genes in various tissues of D. huoshanense were significantly up-regulated after four kinds of abiotic stresses commonly encountered in the growth process, but the extent of up-regulation varied among treatment groups, with drought and cold stress having more significant effects on gene expression levels. Through the identification and functional analysis of DhuFNSⅡ, this study is expected to contribute to the elucidation of the molecular mechanism of the formation of quality metabolites of D. huoshanense, flavonoid C-glycosides, and provide a reference for its quality formation and scientific cultivation.