Raman silent region - based method for detection of pesticides with cyano group.

Based on the fact that not all chemical substances possess good Raman signals, this article focuses on the Raman silent region signals of pesticides with cyano group. Under the optimized conditions of methanol-water (1:1, v/v) as the solvent, irradiation at 302 nm light source for 20 min, and the use of 0.5 mol/L KI as the aggregating agent, Surface-enhanced Raman spectroscopy (SERS) method for azoxystrobin detection was developed by the Raman silent region signal of 2230 cm-1, and verified by detecting the spiked grapes with different concentrations of azoxystrobin. Other four pesticides with cyano group also could be identified at the peak of 2180 cm-1, 2205 cm-1, 2125 cm-1, and 2130 cm-1 for acetamiprid, phoxim, thiacloprid and cymoxanil, respectively. When azoxystrobin or acetamiprid was mixed respectively with chlorpyrifos without cyano group, their SERS signals in the Raman silent region of chlorpyrifos were not interfered, while mixed with cymoxanil in different ratios (1:4, 1:1 and 4:1), respectively, each two pesticides with cyano group could be distinguished by the changes in the Raman silent region. In further, four pesticides with or without cyano group were mixed together in 1:1:1:1 (acetamiprid, cymoxanil, azoxystrobin chlorpyrifos), and each pesticide still could be identified even at 0.5 mg/L. The results showed that the SERS method combined with UV irradiation may provide a new way to monitor the pesticides with C≡N performance in the Raman silent region without interference from the food matrix.

Effect of tannic acid binding on the thermal degradation behavior and product toxicity of boscalid.

The effect of tannic acid (TA) binding on the thermal degradation of boscalid was studied in this work. The results revealed that TA binding has a significant impact on boscalid degradation. The degradation rate constant of bound boscalid was reduced, and its corresponding half-life was significantly prolonged compared to the free state. Four identical degradation products were detected in both states through UHPLC-Q-TOF-MS, indicating that degradation products were not affected by TA binding. Based on DFT and MS analysis, the degradation pathways of boscalid included hydroxyl substitution of chlorine atoms and cleavage of CN and CC bonds. The toxicity of B2 and B3 exceeded that of boscalid. In summary, the binding of TA and boscalid significantly affected the thermal degradation rate of boscalid while preserving the types of degradation products. This study contributed to a fundamental understanding of the degradation process of bound pesticide residues in complex food matrices.

Echinacea purpurea polysaccharide intervene in hepatocellular carcinoma via modulation of gut microbiota to inhibit TLR4/NF-κB pathway.

Echinacea purpurea polysaccharide (EPP) exhibit various pharmacological activities, including immunomodulatory, anti-inflammatory, and anti-tumor effects. In this study, we investigated the potential mechanism of EPP intervention in hepatocellular carcinoma (HCC). The results demonstrated that EPP effectively mitigated liver injury caused by HCC, inhibited the proliferation of HCC, and induced apoptosis. Following EPP intervention, there was a significant increase in propionic acid and butyric acid-producing gut microbiota such as Coprococcus, Clostridium and Roseburia, leading to enhanced expression of intestinal tight junction proteins and the repair of the intestinal barrier. This controls lipopolysaccharide (LPS) leakage, which in turn inhibits the TLR4/NF-κB pathway and reduces the expression of inflammatory factors such as IL-6, as well as migration factors like MMP-2. Metabolomics revealed the downregulation of pyrimidine metabolism and nucleotide metabolism, along with the upregulation of butyrate metabolism in tumor cells. This study demonstrated that EPP effectively regulated LPS leakage by modulating gut microbes, and this modulation influenced the TLR4/NF-κB pathway, ultimately disrupting tumor cell survival induced by HCC in mice.

Coupling dynamics of respiration, gas exchange, and Pseudomonas fluorescens growth on fresh-cut cucumber (Cucumis sativus L.) in passive modified atmosphere packing.

This study established microbial growth models for fresh-cut cucumber packaged with different O2 transmission rate (OTR) films. Biaxially oriented polyamide/low-density polyethylene (BOPA/LDPE) film (Ⅰ: OTR5, Ⅳ: OTR48) and polyethylene (PE) film (Ⅱ: OTR2058, Ⅲ: OTR3875) were used to construct a passive modified atmosphere packaging (MAP). Mathematic models have been established to account for dynamic variations in the O2/CO2 concentration and their impacts on Pseudomonas fluorescens growth. The coupling models included: 1) respiration models of cucumber and P. fluorescens based on Michaëlis-Menten equation, 2) coupling gas exchange models based on Fick's law that contained models of P. fluorescens growth and respiration, 3) coupling microbial growth models contained respiration and gas exchange models. Coupling model with Baranyi function successfully fitted variations of O2/CO2 concentration and P. fluorescens growth in the two packaging. In addition, quality properties of packed fresh-cut cucumber were determined. The film Ⅳ (OTR48) as a high barrier film showed the highest inhibition of P. fluorescens growth, adequately retained its colour, firmness and total soluble solid (TSS) concentration in contrast to the PE films packaging. The constructed coupling models can be utilized for assessing the shelf life and microbial growth of fresh-cut vegetables with spoilage dominated by pseudomonads.

A Review on Gold Nanoclusters for Cancer Phototherapy.

Cancer phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), has been extensively studied in recent years because of its noninvasive properties, high efficiency, improved selectivity, and reduced side effects. Gold nanoclusters (AuNCs) have the advantages of high biocompatibility, high biosafety, excellent photoresponse, and high tumor penetration ability. This review analyzes the use of AuNCs in tumor phototherapy in recent years from three aspects, namely, AuNCs in PDT, AuNCs in PTT, and AuNCs in combination therapy, and presents the high potential of AuNCs in cancer phototherapy. This review aims to provide readers with the unique advantages, diversified application approaches, and bright application prospects of AuNCs in phototherapy and to provide insights into strategies for applying AuNCs to tumor phototherapy.

Ultrasound-Assisted Fermentation to Remove Cadmium from Rice and Its Application.

Rice, which is a major part of the daily diet, is becoming more and more contaminated by cadmium (Cd). This study combined low-intensity ultrasonic waves with the Lactobacillus plantarum fermentation method and optimized this technique by a single-factor and response surface experiment, aiming to solve the practical problems that the current Cd removal methods for rice cannot address, due to the fact that they require a long time (nearly 24 h), which prevents meeting the rice production demands. The described technique required a short time (10 h), and the highest Cd removal reached 67.05 ± 1.38%. Further analysis revealed that the maximum adsorption capacity of Lactobacillus plantarum for Cd increased by nearly 75%, and the equilibrium adsorption capacity increased by almost 30% after the ultrasonic intervention. Additionally, a sensory evaluation and other experiments proved that the properties of the rice noodles prepared from Cd-reduced rice obtained by ultrasound-assisted fermentation were comparable to those of traditional rice noodles, indicating that this method can be used in actual rice production.

Sulfhydryl-functionalized carbon dots as effective probes for fluorescence enhancement detection of patulin.

In this study, sulfydryl-functionalized nitrogen-doped carbon dots (SH-NCDs) was synthesized by amide reaction of hydrothermally synthesized carbon dots with l-cysteine and used to detect patulin selectively. The SH-NCDs exhibited excitation wavelength-independent fluorescence in the range 300-360 nm. The modified sulfhydryl group (-SH) on the surface of NCDs served as a specific recognition site to capture patulin. The addition reaction between patulin and the -SH on the SH-NCDs surface resulted in enhanced fluorescence. SH-NCDs was used as a fluorescent probe for label-free detection of patulin, showing excellent sensitivity in the linear range of 0.1-400 ng mL-1, with detection limits as low as 0.053 ng mL-1. The fluorescent probe has specific selectivity for patulin. The recoveries of patulin in apple juice and grape juice were 88.9 %-99.2 % and 92.5 %-101.8 %, respectively. These results showed that the sensor designed in this experiment selectively detected the target patulin from complex food systems.

Characterization of the interaction between boscalid and tannic acid and its effect on the antioxidant properties of tannic acid.

The binding of pesticide residues and fruit components may have a profound impact on pesticide dissipation and the functional characteristics of the corresponding components. Therefore, the interaction between boscalid and tannic acid (TA, a representative phenolic in fruit) was systematically investigated using spectroscopic, thermodynamic, and computational chemistry methods. A separable system was designed to obtain the boscalid-TA complex. Fourier transform infrared and 1 H-NMR spectroscopies indicated the formation of hydrogen bonds in the complex. Isothermal titration calorimetry showed that the complex bound spontaneously through hydrophobic interactions (ΔG < 0, ΔH > 0, ΔS > 0), with a binding constant of 6.0 × 105  M-1 at 298 K. The molecular docking results further confirmed the formation of hydrogen bonds and hydrophobic interactions in the complex at the molecular level, with a binding energy of -8.43 kcal mol-1 . In addition, the binding of boscalid to TA significantly decreased the antioxidant activity of TA. The binding of boscalid residue to TA was characterized at the molecular level, which significantly reduced the in vitro antioxidant properties of TA. PRACTICAL APPLICATION: This study provides a reference for the molecular mechanisms of the interaction between pesticide residues and food matrices, as well as a basis for regulating bound-state pesticide residues in food.

Polyethylenimine-functionalized nitrogen and sulfur co-doped carbon dots as effective fluorescent probes for detection of Hg2+ ions.

Surface modification of nitrogen and sulfur co-doped carbon quantum dots (N, S-CDs) were performed using cysteine and polyethylenimine as raw materials. The prepared N, S-CDs exhibited excitation-independent in the range of 300-380 nm. Furthermore, mercury(II) ions (Hg2+) can effectively quench the fluorescence intensity of the N, S-CDs. Based on this, we developed a fluorescence sensor with high sensitivity and selectivity to detect Hg2+. Under optimized conditions, the sensor showed good linearity in the range of 0-500 nM, and the limit of detection is 9.2 nM. Further, the sensor showed high sensitivity to Hg2+ in lake water and rice samples. The recovery of the Hg2+ in lake water and rice samples ranged between 98.2 % and 109.5 % with a relative standard deviation below 5.8 %. With outstanding sensitivity and selectivity, the fluorescence sensor provides a promising platform for monitoring Hg2+ in real samples.

Cadmium in food: Source, distribution and removal.

Since its discovery, cadmium (Cd) has played an important role in industry and brought certain conveniences to mankind, used for electroplating and making rechargeable batteries, etc. Cd is also a harmful pollutant, which will enter the food chain and cause damage to human tissues and organs. Food is the main source of Cd in the human body, so various technologies for removing Cd from food have been studied. These technologies are based on the binding mechanism between Cd and proteins. In this work, the enrichment of Cd and the harm of Cd are described. And the binding mechanism between Cd and protein is summarized. Finally, the removal technologies of Cd are prospected. This review analyzes the methods of removing cadmium from food from the perspective of the combination of cadmium and protein, which provides insights for ensuring food safety and reducing the harm of heavy metals to the human body.

G-quadruplex based biosensors for the detection of food contaminants.

G-quadruplex (G4) is a very interesting DNA structure, commonly associated with cancer and its treatment. With flexible binding ability, G4 has been extended as a significant component in biosensors. On account of its simple operation, high sensitivity and low cost, G4-based biosensors have attracted considerable interest for the detection of food contaminants. In this review, research published in recent 5 years is collated from a principle perspective, that is target recognition and signal transduction. Contaminants with G4 binding capacity are illustrated, emerging G4-based biosensors including colorimetric, electrochemical and fluorescent sensors are also elaborated. The current review indicates that G4 has provided an efficient and effective solution for the rapid detection of food contaminants. A distinctive feature of G4 as recognition unit is the simple composition, but the selectivity is still unsatisfactory. As signal reporter, G4/hemin DNAzyme has not only achieved amplified signals, but also enabled visualized detection, which offers great potential for on-site measurement. With improved selectivity and visualized signal, the combination of aptamer and G4 seems to be an ideal strategy. This promising combination should be developed for the real-time monitor of multiple contaminants in food matrix.

Establishment of a prognostic model for gastric cancer patients who underwent radical gastrectomy using machine learning: a two-center study.

Objective: Gastric cancer is a prevalent gastrointestinal malignancy worldwide. In this study, a prognostic model was developed for gastric cancer patients who underwent radical gastrectomy using machine learning, employing advanced computational techniques to investigate postoperative mortality risk factors in such patients. Methods: Data of 295 patients with gastric cancer who underwent radical gastrectomy at the Department of General Surgery of Affiliated Hospital of Xuzhou Medical University (Xuzhou, China) between March 2016 and November 2019 were retrospectively analyzed as the training group. Additionally, 109 patients who underwent radical gastrectomy at the Department of General Surgery Affiliated to Jining First People's Hospital (Jining, China) were included for external validation. Four machine learning models, including logistic regression (LR), decision tree (DT), random forest (RF), and gradient boosting machine (GBM), were utilized. Model performance was assessed by comparing the area under the curve (AUC) for each model. An LR-based nomogram model was constructed to assess patients' clinical prognosis. Results: Lasso regression identified eight associated factors: age, sex, maximum tumor diameter, nerve or vascular invasion, TNM stage, gastrectomy type, lymphocyte count, and carcinoembryonic antigen (CEA) level. The performance of these models was evaluated using the AUC. In the training group, the AUC values were 0.795, 0.759, 0.873, and 0.853 for LR, DT, RF, and GBM, respectively. In the validation group, the AUC values were 0.734, 0.708, 0.746, and 0.707 for LR, DT, RF, and GBM, respectively. The nomogram model, constructed based on LR, demonstrated excellent clinical prognostic evaluation capabilities. Conclusion: Machine learning algorithms are robust performance assessment tools for evaluating the prognosis of gastric cancer patients who have undergone radical gastrectomy. The LR-based nomogram model can aid clinicians in making more reliable clinical decisions.

Brassica rapa L. (Tibetan turnip) prevents sleep-deprivation induced cognitive deficits via the inhibition of neuroinflammation and mitochondrial depolarization.

Brassica rapa L., an edible, feeding and medicinal plant cultivated on the Tibetan plateau with altitudes above 3800 m, has several pharmacological effects. However, its therapeutic effects against memory impairment and central fatigue have yet to be conclusively established. In this study, the Y-maze and Morris water maze tasks revealed that Brassica rapa L. aqueous extract (BE) significantly ameliorated cognitive deficits of sleep deprivation (SD)-treated mice. Moreover, BE treatment partially alleviated SD-induced reductions in the levels of peripheral energy metabolism, and significantly decreased inflammatory factor levels in serum and hippocampus. In addition, BE treatment significantly relieved central fatigue and stabilized the excitability as well as activities of neurons by regulating the levels of hypothalamus tryptophan metabolites and striatum neurotransmitters. The neuroprotective effects of BE were also confirmed using glutamate-treated HT22 cells, whereby BE pretreatment significantly attenuated intracellular ROS production and mitochondrial depolarization via adenosine 5'-monophosphate activated protein kinase/peroxisome proliferators-activated receptors (AMPK/PPAR-γ) signaling pathways. Thus, BE might probably prevent SD-induced learning and memory deficits by inhibiting neuroinflammation and restoring mitochondrial energy metabolism in the hippocampus. These findings imply that BE is a potential complementary therapy for those suffering from deficient sleep or neurometabolic disorders, although this needs verification by prospective clinical studies.

Preparation and characterization of chitosan-based antimicrobial films containing encapsulated lemon essential oil by ionic gelation and cranberry juice.

Research about biodegradable antimicrobial films continues to receive a lot of attention due to the plastic pollution crisis and the need for environment-friendly and safe food products. In this study, we developed chitosan-based antimicrobial films using a combination of encapsulated lemon essential oil (LEO) by ionic gelation and cranberry juice and evaluated the performance of the films. Our results indicated that the incorporation of LEO microspheres and cranberry juice into the chitosan films improved the UV barrier and thermal properties as well as antioxidant activity of the films. The increase in antioxidants was consistent with the chemical components in LEO and cranberry juice as determined by GC-MS; some of which possess antioxidant properties. Furthermore, following antimicrobial activity test, considerable inhibition halo of 11 and 20 mm were observed respectively against fungi Candida albicans and Penicillium roqueforti, particularly in presence of the film containing both LEO microspheres and cranberry juice.

Simultaneous Determination of Antibiotics, Mycotoxins, and Hormones in Milk by an 8-17 DNAzyme-Based Enzyme-Linked Immunosorbent Assay.

The simultaneous detection of three kinds of small-molecule contaminants (antibiotics, mycotoxins, and hormones) in milk was realized by using an 8-17 DNAzyme-based fluorescent enzyme-linked immunosorbent assay (ELISA), in which 8-17 DNAzyme was utilized as the catalytic enzyme for amplifying the signal. Compared with the conventional ELISA in which horseradish peroxidase is used as the catalyzing factor, this 8-17 DNAzyme-based ELISA could achieve multicolor signal output with lower detection limits. The linearities for chloramphenicol, 17ß-estradiol, and aflatoxin M1 were in the range of 0.3 ng/mL-3 µg/mL, 3 ng/mL-3 µg/mL, and 3 pg/mL-3 ng/mL with quantitation limits of 0.3, 3, and 0.003 ng/mL, respectively. This proposed scheme demonstrated that the 8-17 DNAzyme might be an effective substitute for horseradish peroxidase in ELISA for the development of ultrasensitive and multicolor fluorescence immunoassay, which would stimulate the development of ELISA in a new orientation.

Feasibility and reproducibility of a plasma-based multiplex DNA methylation assay for early detection of gastric cancer.

BACKGROUND: Gastric cancer (GC) is a leading cause of cancer death and an important barrier to increasing life expectancy in China. Early detection of GC can significantly reduce its mortality rate. METHODS: A new plasma-based multiplex DNA methylation assay combining simultaneous detection of three biomarkers (KCNQ5, C9orf50 and CLIP4) and one control gene (ACTB) was developed. It was used to examine 12 paired tissue samples and a training cohort of 151 plasma samples. Its performance was subsequently confirmed in validation cohort 1 (n = 105) and validation cohort 2 (n = 139). RESULTS: Three methylation markers showed significantly higher methylation levels in GC tissues than in paired adjacent tissues. The assay showed a sensitivity of 67.9 % with a specificity of 86.6 % for GC detection in the training cohort, and the AUC was 0.786 (95 % CI: 0.701-0.855). The methylation levels in GC patients were significantly higher than those in benign gastric tumors and in control group. Meanwhile, the assay achieved a sensitivity of 65.5 % with a specificity of 90.0 % in the validation cohort 1, and the AUC was 0.805 (95 % CI: 0.716-0.876). In the validation cohort 2, its sensitivity and specificity were 73.7 % and 84.1 %, respectively, and the AUC was 0.851 (95 % CI: 0.776-0.909). CONCLUSION: The plasma-based multiplex DNA methylation assay was highly specific for GC early detection. It has the potential to become an alternative approach to improve diagnosis of GC in the clinics.

A Study on the Mechanism of the Sedative-hypnotic Effect of Cinnamomum camphora chvar. Borneol Essential Oil Based on Network Pharmacology.

In this paper, we investigated the sedative-hypnotic effect of Cinnamomum camphora chvar. Borneol essential oil (BEO, 16.4% borneol), a by-product of steam distillation of Cinnamomum camphora chvar. Borneol, from which natural crystalline borneol (NCB, 98.4% borneol) is obtained. Using locomotor activity tests and pentobarbital sodium-induced sleep test, it was found that BEO significantly reduced locomotor activity (p < 0.05), shortened sleep latency (p < 0.0001), prolonged sleep duration (p < 0.05), and had a sedative-hypnotic effect. We constructed the "components-targets-signaling pathways" and "proteinprotein interaction" (PPI) network of BEO using network pharmacology. The results show that the 24 active components of BEO acted on 17 targets, mainly through response to alkaloid and catecholamine transport, and neuroactive ligand-receptor interaction. The PPI network identified 12 key proteins, mainly dopamine receptor (DR)D2, opioid receptor mu 1 (OPRM1), and opioid receptor kappa 1 (OPRK1), and we further analyzed the active components and targets of BEO through molecular docking. The results showed that the active components and targets obtained by network pharmacology analyses had good binding activity, which reflected their multi-component, multi-target, multi-pathway action characteristics. This paper provides a theoretical basis for further study of the mechanism of action of BEO in the treatment of insomnia.

Ultrasonic stimulation of milk fermentation: effects on degradation of pesticides and physiochemical, antioxidant, and flavor properties of yogurt.

BACKGROUND: Ultrasound has the potential to increase microbial metabolic activity, so this study explored the stimulatory effect of ultrasound pre-treatment on the degradation of four common pesticides (fenitrothion, chlorpyrifos, profenofos, and dimethoate) during milk fermentation by Lactobacillus plantarum and its effect on yogurt quality. RESULTS: Appropriate ultrasound pretreatment significantly enhanced the growth of L. plantarum. The degradation percentages of pesticides increased by 19-38% under ultrasound treatment. Ultrasonic intensity, pulse duty cycle, and duration time were key factors affecting microbial growth and pesticide degradation. Under optimal ultrasonic pre-treatment conditions, the degradation rate constants of four pesticides were at least 3.4 times higher than those without sonication. In addition, such ultrasound pretreatment significantly shortened yogurt fermentation time, increased the water holding capacity, hardness and antioxidant activity of the yogurt, and improved the flavor quality of the yogurt. CONCLUSION: Ultrasonic pretreatment significantly accelerated the degradation of the four pesticides during yogurt fermentation. In addition, such ultrasound pretreatment increased the efficiency of yogurt making and improved the quality of yogurt in terms of water holding capacity, firmness, antioxidant activity, and flavor. These findings provide a basis for the application of ultrasound to the removal of pesticide residues and quality improvement of yogurt. © 2022 Society of Chemical Industry.

Construction of fluorescent logic gates for the detection of mercury(II) and ciprofloxacin based on phycocyanin.

Chemical pollutants such as heavy metals and antibiotics in the environment pose a huge threat to humans and animals. Our studies have demonstrated that the fluorescence of phycocyanin showed quenching responses towards both mercury (Hg2+) and ciprofloxacin (CIP), which acted in accordance with the 'OR' molecular logic gate. In order to discriminate Hg2+and CIP in application scenarios, cysteine (Cys) was utilized to design another 'INHIBIT' logic gate, in which Hg2+and Cys were the two inputs. Thus, an intelligent biosensor with dual-target identification capacity was successfully developed by using a fluorescent natural protein in an ingenious logic gate system.

Targeting tumor associated macrophages in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) contains numerous immune cell stroma, which constitutes the tumor microenvironment (TME). Tumor-associated macrophages (TAMs) represent the major compartment of immune cell stroma of HCC and play an important role in HCC pathogenesis, involving in immunosuppressive, angiogenesis, tumor invasion and metastasis, metabolic support, drug resistance, and HCC stem cells malignant transformation. Current targeting TAMs to treat HCC have been achieved a promising therapeutic outcome by eliminating TAMs present, blocking recruitment of TAMs, reprogramming TAMs polarization, modulating TAMs products and restoring TAMs phagocytic capacity. This review summarizes what we have known on TAMs and HCC, discussing the roles of TAMs in HCC development and the possible approaches for TAMs-targeted therapy as potential targets for HCC treatment.