Effects of Temperature, Ionic Strength and Humic Acid on the Transport of Graphene Oxide Nanoparticles in Geosynthetic Clay Liner.

With the wide application of graphene oxide nanoparticles (GONPs), a great amount of GONP waste is discarded and concentrated in landfills. It has been proven that GONPs have strong toxicity and could gather toxic substances due to their high adsorption capacity. GONPs will seriously pollute the surrounding environment if they leak through the geosynthetic clay liner (GCL) in landfills. To investigate various factors (temperature, ionic strength (IS) and humic acid (HA)) on the transport and retention of GONPs in the GCL, a self-designed apparatus was created and column tests were carried out. The experimental results show that GONPs could be transported through the GCL. The mobility and sorption ratio of GONPs in GCL decreased with an increase in temperature and IS, and increased with an increase in HA. The temperature had little effect on the deposition ratio of GONPs in the GCL. The deposition ratio of GONPs in the GCL increased with IS, and decreased with an increase in HA. The transport of GONPs in GCL, glass beads and quartz sand was compared, and the results show that the retention ability of the GCL is much better than other porous materials. The experimental results could provide significant references for the pollution treatment in landfills.

Astrocyte-mediated regulation of BLAWFS1 neurons alleviates risk-assessment deficits in DISC1-N mice.

Assessing and responding to threats is vital in everyday life. Unfortunately, many mental illnesses involve impaired risk assessment, affecting patients, families, and society. The brain processes behind these behaviors are not well understood. We developed a transgenic mouse model (disrupted-in-schizophrenia 1 [DISC1]-N) with a disrupted avoidance response in risky settings. Our study utilized single-nucleus RNA sequencing and path-clamp coupling with real-time RT-PCR to uncover a previously undescribed group of glutamatergic neurons in the basolateral amygdala (BLA) marked by Wolfram syndrome 1 (WFS1) expression, whose activity is modulated by adjacent astrocytes. These neurons in DISC1-N mice exhibited diminished firing ability and impaired communication with the astrocytes. Remarkably, optogenetic activation of these astrocytes reinstated neuronal excitability via D-serine acting on BLAWFS1 neurons' NMDA receptors, leading to improved risk-assessment behavior in the DISC1-N mice. Our findings point to BLA astrocytes as a promising target for treating risk-assessment dysfunctions in mental disorders.

Influence of Electrospinning Parameters on the Morphology of Electrospun Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Fibrous Membranes and Their Application as Potential Air Filtration Materials.

A large number of non-degradable materials have severely damaged the ecological environment. Now, people are increasingly pursuing the use of environmentally friendly materials to replace traditional chemical materials. Polyhydroxyalkonates (PHAs) are receiving increasing attention because of the unique biodegradability and biocompatibility they offer. However, the applications of PHAs are still limited due to high production costs and insufficient study. This project examines the optimal electrospinning parameters for the production of PHA-based fibrous membranes for air filtration. A common biodegradable polyester, Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), was electrospun into a nanofibrous membrane with a well-controlled surface microstructure. In order to produce smooth, bead-free fibers with micron-scale diameters, the effect of the process parameters (applied electric field, solution flow rate, inner diameter of hollow needle, and polymer concentration) on the electrospun fiber microstructure was optimized. The well-defined fibrous structure was optimized at an applied electric field of 20 kV, flow rate of 0.5 mL/h, solution concentration of 12 wt.%, and needle inner diameter of 0.21 mm. The morphology of the electrospun PHBV fibrous membrane was observed by scanning electron microscopy (SEM). Fourier transform infrared (FTIR) and Raman spectroscopy were used to explore the chemical signatures and phases of the electrospun PHBV nanofiber. The ball burst strength (BBS) was measured to assess the mechanical strength of the membrane. The small pore size of the nanofiber membranes ensured they had good application prospects in the field of air filtration. The particle filtration efficiency (PFE) of the optimized electrospun PHBV fibrous membrane was above 98% at standard atmospheric pressure.

B cells in head and neck squamous cell carcinoma: current opinion and novel therapy.

Head and neck squamous cell carcinoma (HNSCC) is a common malignant tumour. Despite advancements in surgery, radiotherapy and chemotherapy, which have improved the prognosis of most patients, a subset of patients with poor prognoses still exist due to loss of surgical opportunities, postoperative recurrence, and metastasis, among other reasons. The tumour microenvironment (TME) is a complex organization composed of tumour, stromal, and endothelial cells. Communication and interaction between tumours and immune cells within the TME are increasingly being recognized as pivotal in inhibiting or promoting tumour development. Previous studies on T cells in the TME of HNSCC have yielded novel therapeutic possibilities. However, the function of B cells, another adaptive immune cell type, in the TME of HNSCC patients has yet to be determined. Recent studies have revealed various distinct subtypes of B cells and tertiary lymphoid structures (TLSs) in the TME of HNSCC patients, which are believed to impact the efficacy of immune checkpoint inhibitors (ICIs). Therefore, this paper focuses on B cells in the TME to explore potential directions for future immunotherapy for HNSCC.

Non-targeted effects of nitrification inhibitors on soil free-living nitrogen fixation modified with weed management.

Biological nitrogen fixation and nitrification inhibitor applications contribute to improving soil nitrogen (N) availability, however, free-living N fixation affected by nitrification inhibitors has not been effectively evaluated in soils under different weed management methods. In this study, the effects of the nitrification inhibitors dicyandiamide (DCD) and 3, 4-dimethylpyrazole phosphate (DMPP) on the nitrogenase, nifH gene，and diazotrophic communities in soils under different weed management methods (AMB, weeds growth without mowing or glyphosate spraying; GS, glyphosate spraying; MSG, mowing and removing weeds and glyphosate spraying; and WM, mowing aboveground weeds) were investigated. Compared to the control counterparts, the DCD application decreased soil nitrogenase activity and nifH gene abundance by 4.5 % and 37.9 %, respectively, under the GS management method, and the DMPP application reduced soil nitrogenase activity by 20.4 % and reduced the nifH gene abundance by 83.4 % under the MSG management method. The application of nitrification inhibitors significantly elevated soil NH4+-N contents but decreased NO3--N contents, which had adverse impacts on soil nifH gene abundance and nitrogenase activity. The nifH gene abundances were also negatively impacted by dissolved organic N and Geobacter but were positively affected by available phosphorus and diazotrophic community structures. Nitrification inhibitors significantly inhibited Methylocella but stimulated Rhizobiales and affected soil diazotrophic communities. The nitrification inhibitors DCD and DMPP significantly altered soil diazotrophic community structures, but weed management outweighed nitrification inhibitors in reshaping soil diazotrophic community structures. The non-targeted effects of the nitrification inhibitors DMPP and DCD on soil free-living N fixation were substantially influenced by the weed management methods.

Spatial and temporal variations of vegetation cover and its influencing factors in Shandong Province based on GEE.

Economic development has rapidly progressed since the implementation of reform and opening up policies, posing significant challenges to sustainable development, especially to vegetation, which plays a crucial role in maintaining ecosystem service functions and promoting green low-carbon transformations. In this study, we estimated the fractional vegetation cover (FVC) in Shandong Province from 2000 to 2020 using the Google Earth Engine (GEE) platform. The spatial and temporal changes in FVC were analyzed using gravity center migration analysis, trend analysis, and geographic detector, and the vegetation changes of different land use types were analyzed to reveal the internal driving mechanism of FVC changes. Our results indicate that vegetation cover in Shandong Province was in good condition during the period 2000 to 2020. The high vegetation cover classes dominated, and overall changes were relatively small, with the center of gravity of vegetation cover generally shifting towards the southwest. Land use type, soil type, population density, and GDP factors had the most significant impact on vegetation cover change in Shandong Province. The interaction of these factors enhanced the effect on vegetation cover change, with land use type and soil type having the highest degree of influence. The observational results of this study can provide data support for the policy makers to formulate new ecological restoration strategies, and the findings would help facilitate the sustainability management of regional ecosystem and natural resource planning.

Nighttime light perspective in urban resilience assessment and spatiotemporal impact of COVID-19 from January to June 2022 in mainland China.

The outbreak of the coronavirus disease 2019 (COVID-19) epidemic has resulted in large threats and damage to society and the economy. In this study, we evaluate and verify the comprehensive resilience and spatiotemporal impact of the COVID-19 epidemic from January to June 2022 in mainland China based on multisource data. First, we adopt a combination of the mandatory determination method and the coefficient of variation method to determine the weight of the urban resilience assessment index. Furthermore, Beijing, Shanghai, and Tianjin were selected to verify the feasibility and accuracy of the resilience assessment results based on the nighttime light data. Finally, the epidemic situation was dynamically monitored and verified with population migration data. The results show that urban comprehensive resilience of mainland China is shown in the distribution pattern of higher resilience in the middle east and south and lower resilience in the northwest and northeast. Moreover, the average light intensity index is inversely proportional to the number of newly confirmed and treated cases of COVID-19 in the local area. This study provides a scientific reference to improve the comprehensive resilience of cities to achieve the goals of sustainable development (SDGs 11): make cities and human settlements resilient and sustainable.

A novel tyrosine tRNA-derived fragment, tRFTyr, induces oncogenesis and lactate accumulation in LSCC by interacting with LDHA.

BACKGROUND: Transfer (t)RNA-derived small RNA (tsRNA), generated from precursor or mature tRNA, is a new type of small non-coding RNA (sncRNA) that has recently been shown to play a vital role in human cancers. However, its role in laryngeal squamous cell carcinoma (LSCC) remains unclear. METHODS: We elucidated the expression profiles of tsRNAs in four paired LSCC and non-neoplastic tissues by sequencing and verified the sequencing data by quantitative real-time PCR (qRT-PCR) of 60 paired samples. The tyrosine-tRNA derivative tRFTyr was identified as a novel oncogene in LSCC for further study. Loss-of-function experiments were performed to evaluate the roles of tRFTyr in tumorigenesis of LSCC. Mechanistic experiments including RNA pull-down, parallel reaction monitoring (PRM) and RNA immunoprecipitation (RIP) were employed to uncover the regulatory mechanism of tRFTyr in LSCC. RESULTS: tRFTyr was significantly upregulated in LSCC samples. Functional assays showed that knockdown of tRFTyr significantly suppressed the progression of LSCC. A series of mechanistic studies revealed that tRFTyr could enhance the phosphorylated level of lactate dehydrogenase A (LDHA) by interacting with it. The activity of LDHA was also activated, which induced lactate accumulation in LSCC cells. CONCLUSIONS: Our data delineated the landscape of tsRNAs in LSCC and identified the oncogenic role of tRFTyr in LSCC. tRFTyr could promote lactate accumulation and tumour progression in LSCC by binding to LDHA. These findings may aid in the development of new diagnostic biomarkers and provide new insights into therapeutic strategies for LSCC.

Long-term exposure of polytetrafluoroethylene-nanoplastics on the nitrogen removal and extracellular polymeric substances in sequencing batch reactor.

The impact of polytetrafluoroethylene-nanoplastics (PTFE-NPs) on biological sewage disposal was delved, containing nitrogen remotion, microbiological activity and composition of extracellular polymer (EPS). The addition of PTFE-NPs reduced the removal efficiencies of chemical oxygen demand (COD) and ammonia nitrogen (NH4+-N) by 3.43 % and 2.35 %, respectively. In comparison with no PTFE-NPs, the specific oxygen uptake rate (SOUR), specific ammonia oxidation rate (SAOR), specific nitrite oxidation rate (SNOR) and specific nitrate reduction rate (SNRR) decreased by 65.26 %, 65.24 %, 41.77 % and 54.56 %, respectively. The PTFE-NPs inhibited the activities of nitrobacteria and denitrobacteria. It was worth noting that, nitrite oxidized bacterium was more resistant to adverse environments than ammonia oxidizing bacterium. Compared with no PTFE-NPs, the reactive oxygen species (ROS) content and lactate dehydrogenase (LDH) grew by 130 % and 50 % under PTFE-NPs pressure. The appearance of PTFE-NPs affected the normal function of microorganisms by inducing endocellular oxidative stress and destroying the completeness of the cytomembrane. The protein (PN) and polysaccharide (PS) levels in loosely bound EPS (LB-EPS) and tightly bound EPS (TB -EPS) increased by 4.96, 0.70, 3.07 and 0.71 mg g-1 VSS, under PTFE-NPs. Meanwhile, the PN/PS ratios of LB-EPS and TB -EPS increased from 6.18 and 6.41-11.04 and 9.29, respectively. The LB-EPS might provide sufficient binding sites for PTFE-NPs adsorption due to its loose and porous structure. The defense mechanism of bacteria against PTFE-NPs was mainly the PN in loosely bound EPS. Moreover, the functional groups referred to the complexation of EPS with PTFE-NPs were mainly related to N-H, CO, and C-N in proteins and O-H in polysaccharides.

Silencing SOX11 Alleviates Allergic Rhinitis by Inhibiting Epithelial-Derived Cytokines

Background: Allergic rhinitis is a chronic inflammatory disease of the nasal mucosa affecting the quality of life of patients. SRY-box transcription factor 11 (SOX11) was reported to play important roles in inflammatory responses, but its role in AR is poorly understood. Aims: To explore the role of SOX11 in the development of allergic rhinitis. Study Design: Cell culture and animal study. Methods: An in vivo murine allergic rhinitis model was established using ovalbumin treatment in female mice. Interleukin-13-stimulated human nasal mucosa epithelial cells were used for in vitro studies. Expression levels of SOX11, epithelial-derived cytokines, and mucin were determined in both modesls. Results: SOX11 was highly expressed in allergic rhinitis mice. Allergy symptoms, serum ovalbumin-specific IgE, histamine, eosinophils, goblet cells, and type 2 cytokine secretion were increased in ovalbumin-treated mice. Furthermore, allergic rhinitis mice exhibited overproduction of epithelial-derived cytokines (thymic stromal lymphopoietin, interleukin-25, interleukin-33), C-C motif chemokine ligand 26 (CCL26), and mucin 5 AC (MUC5AC). Silencing SOX11 alleviated the behavioral symptoms and upregulation of epithelial-derived cytokines, CCL26, and MUC5AC. In human nasal mucosa epithelial cells, interleukin-13 enhanced SOX11 expression in a time-dependent manner, and signal transducer and activator of transcription 6 (STAT6) was involved in the interleukin-13-mediated expression of SOX11 by regulating transcription. Knockdown of SOX11 reduced epithelial-derived cytokine expression and MUC5AC levels in interleukin-13-treated human nasal mucosa epithelial cells. Conclusion: SOX11 plays a critical role in allergic rhinitis development by regulating epithelial-derived cytokines and might be a new therapeutic target for allergic rhinitis.

Effect of polytetrafluoroethylene nanoplastics on combined inhibition of ciprofloxacin and bivalent copper on nitrogen removal, sludge activity and microbial community in sequencing batch reactor.

The work aimed to explore effects of polytetrafluoroethylene nanoplastics on joint inhibitions of ciprofloxacin and bivalent copper on the nitrogen removal in a sequencing batch reactor and its potential mechanisms. The addition of bivalent copper and/or ciprofloxacin reduced the ammonia nitrogen elimination rate with or without polytetrafluoroethylene nanoplastics. Adsorption kinetics and thermodynamics showed the binary bivalent copper and ciprofloxacin promoted their adsorptions by polytetrafluoroethylene nanoplastics. Polytetrafluoroethylene nanoplastics enhanced combined toxicities of ciprofloxacin and bivalent copper to sludge activities and microbial community involved into nitrification and denitrification due to the adsorption of ciprofloxacin and bivalent copper by polytetrafluoroethylene nanoplastics. With or without polytetrafluoroethylene nanoplastics, bivalent copper and/or ciprofloxacin caused more obvious level changes of protein than polysaccharide. This study provides novel insights for understanding the effect of combined heavy metals and antibiotics on the performance in a sequencing batch reactor with the nanoplastics stress.

AGs-Unet: Building Extraction Model for High Resolution Remote Sensing Images Based on Attention Gates U Network.

Building contour extraction from high-resolution remote sensing images is a basic task for the reasonable planning of regional construction. Recently, building segmentation methods based on the U-Net network have become popular as they largely improve the segmentation accuracy by applying 'skip connection' to combine high-level and low-level feature information more effectively. Meanwhile, researchers have demonstrated that introducing an attention mechanism into U-Net can enhance local feature expression and improve the performance of building extraction in remote sensing images. In this paper, we intend to explore the effectiveness of the primeval attention gate module and propose the novel Attention Gate Module (AG) based on adjusting the position of 'Resampler' in an attention gate to Sigmoid function for a building extraction task, and a novel Attention Gates U network (AGs-Unet) is further proposed based on AG, which can automatically learn different forms of building structures in high-resolution remote sensing images and realize efficient extraction of building contour. AGs-Unet integrates attention gates with a single U-Net network, in which a series of attention gate modules are added into the 'skip connection' for suppressing the irrelevant and noisy feature responses in the input image to highlight the dominant features of the buildings in the image. AGs-Unet improves the feature selection of the attention map to enhance the ability of feature learning, as well as paying attention to the feature information of small-scale buildings. We conducted the experiments on the WHU building dataset and the INRIA Aerial Image Labeling dataset, in which the proposed AGs-Unet model is compared with several classic models (such as FCN8s, SegNet, U-Net, and DANet) and two state-of-the-art models (such as PISANet, and ARC-Net). The extraction accuracy of each model is evaluated by using three evaluation indexes, namely, overall accuracy, precision, and intersection over union. Experimental results show that the proposed AGs-Unet model can improve the quality of building extraction from high-resolution remote sensing images effectively in terms of prediction performance and result accuracy.

Establishment of a non-squamous cell carcinoma of the larynx nomogram prognostic model and prognosis analysis.

OBJECTIVE: We aimed to compare the prognosis of laryngeal squamous cell carcinoma (LSCC) and nSCCs of the larynx.Then we established a nomogram for nSCCs of the larynx. METHODS: Prognosis between the 529 pairs nSCCs of the larynx patients and LSCC patients were compared after propensity score matching (PSM). 591 nSCCs of the larynx patients were divided into the modeling and validation groups. Univariate and multivariate Cox analyses obtain independent prognostic factors, which were then included in the nomogram to predict the 3 and 5 year survival. Prognostic accuracy of the nomogram was evaluated using the consistency index (C-index) and the calibration curve. RESULTS: Prognosis of nSCCs of the larynx was poorer than LSCC. Age, race, tumor location, tumor-node-metastasis stage, and method were independent prognostic factors of nSCCs of the larynx (P < 0.05). Internal and external validation proves the nomogram reliable CONCLUSION: The nomogram showed good prognostic accuracy and would assist clinicians in making more accurate evaluations for patients.

[Expression and significance of Treg/Th17 and CD4+/CD8+ T lymphocytes in experimental periodontitis in rats].

PURPOSE: To explore the expression of helper T cell 17/regulatory T cell (Th17/Treg) and CD4+/CD8+ T lymphocyte in experimental periodontitis in rats, and analyze its clinical significance. METHODS: Twenty SPF male SD rats were randomly divided into experimental group (inoculate Porphyromonas gingivalis suspension into gingival sulcus) and control group, with 10 rats in each group. The experimental group was smeared with Porphyromonas gingivalis suspension every other day within 1 week after operation, and the two groups were caged for 8 weeks. After the rats were sacrifical under anesthesia, the jaw tissue of the left maxillary second molar was stained with methylene blue to observe and measure the loss of alveolar bone (ABL). Hematoxylin-eosin (H-E) staining was used to observe the histopathological changes of the jaw. Rat peripheral blood mononuclear cells (PBMC) and T cells were isolated and cultured, Treg, Th17 cells and CD4+, CD8+ T lymphocytes in peripheral blood were detected by flow cytometry. The levels of serum interleukin-17(IL-17), IL-10 and IL-4, INF-γ were detected by enzyme-linked immunosorbent assay (ELISA). Expression changes of retinoic acid related orphan nuclear receptor (RORγt), forkhead wing like transcription factor 3 (Foxp3) and gap junction protein(Cx40) in jaw tissue were detected by Western blot. The data were statistically analyzed by SPSS 19.0 software package. RESULTS: Compared with the control group, ABL, peripheral blood Th17 ratio, Th17/Treg ratio, CD4+ ratio, CD4+/CD8+ T lymphocyte ratio, serum IL-17, IL-10 and IL-4 level, Foxp3 and Cx40 protein in jaw tissue were signifinantly increased in the experimental group(P<0.05), while Treg ratio, INF-γ, RORγt protein in jaw tissue significantly decreased(P<0.05) in the experimental group. CONCLUSIONS: Imbalance of Treg/Th17 and CD4+/CD8+ T lymphocytes leads to the abnormal high expression of inflammatory factors IL-17, IL-10 and IL-4, which may be closely related to the pathogenesis of experimental periodontitis.

Effects of food matrix and probiotics on the bioavailability of curcumin in different nanoformulations.

BACKGROUND: Nanoparticles can improve the bioavailability of bioactive compounds. Concomitant intake of food can affect pharmacokinetic profiles by altering dissolution, absorption, metabolism, and elimination behavior. Studies on the effects of food and its supplements on the bioavailability of bioactives in nanoformulations are few. In this study, the effects of typical food (milk, sugar, high-fat diet, and regular kibble) and a widely consumed probiotic [Bifidobacterium lactis Bb-12® (Bb-12)] on the bioavailability of curcumin in four formulations [simply suspended curcumin (Cur-SS) and curcumin in nanoemulsions (Cur-NEs), in single-walled carbon nanotubes (Cur-SWNTs), and in nanostructured lipid carriers (Cur-NLCs)] were investigated. RESULTS: Fasting treatment and sugar co-ingestion can significantly enhance the bioavailability of curcumin in Cur-NEs and Cur-SWNTs, respectively. Compared with the fasting treatment, co-ingestion with regular kibble reduced the absorption of curcumin in Cur-NEs and Cur-SWNTs. Ingesting milk along with Cur-NE is also not recommended. The mechanisms behind these phenomena were briefly discussed. This study revealed for the first time that the intestinal colonization of Bb-12 reduces the bioavailability of curcumin and this reduction can be attenuated by nanoformulations SWNTs and NLCs, but not NEs. The reason for this difference was the protective effects of the former two nanoformulations against curcumin degradation by Bb-12 according to in vitro experiments. CONCLUSION: Dietary status (including supplementary probiotics) can dramatically influence the bioavailability of curcumin in nanoformulations. © 2021 Society of Chemical Industry.

A microscale solid-phase microextraction probe for the in situ analysis of perfluoroalkyl substances and lipids in biological tissues using mass spectrometry.

The simultaneous analysis of perfluoroalkyl substances (PFASs) and lipids in biological tissues is of importance, especially for in situ and microscale analysis, because it provides significant information to understand the relevance of content, composition, and distribution of lipids to the bioaccumulation of PFASs as well as lipid metabolism affected by the biotoxicity of PFASs. In this study, we report the development of a novel ambient mass spectrometry method for the rapid, in situ, and microscale analysis of PFASs and lipids simultaneously in biological tissues for the investigation of their biological correlation. A microscale solid-phase microextraction (SPME) probe with a probe-end diameter of several-µm was employed for in situ and microscale sampling of biological tissues after PFAS exposure. The SPME probe showed a desirable capacity for the enrichment of PFASs and lipid species simultaneously. After sampling and extraction, the loaded SPME probe was directly applied for nanoESI-MS analysis under ambient and open-air conditions. A high-resolution Fourier transform ion cyclotron resonance (FTICR) mass spectrometer operated in the field-induced mode was introduced to record mass spectra using fast polarity switching between positive and negative ion detection. Most of the lipid species were recorded in the positive ion mass spectrum, and PFASs were recorded in the negative ion mass spectrum. By using the developed method, the in situ analysis of PFASs and lipids in the muscle, brain, heart, kidney, liver, and intestine of zebrafish was realized. In addition, simultaneously imaging PFASs and lipids in individual Daphnia magna was successfully achieved for the investigation of their biological correlation.

Sensitive analysis of trace macrolide antibiotics in complex food samples by ambient mass spectrometry with molecularly imprinted polymer-coated wooden tips.

In this article, an ambient mass spectrometric method with molecularly imprinted polymer (MIP)-coated wooden tips was developed for sensitive analysis of trace macrolide antibiotics in complex food samples. A novel solid-phase microextraction (SPME) probe was prepared, via the modification of a layer MIP coating (with roxithromycin as template molecule) on the surface of wooden tips. The obtained MIP-coated wooden-tip SPME probe can be applied directly to enrich trace macrolide antibiotics from complex food samples, with enrichment factors of 244-1604, 72-370, and 12-82 folds for analysis of five investigated macrolide antibiotics in drinking water, honey, and milk samples, respectively. After extraction, a high voltage and some spray solvent were applied on the loaded SPME probe to desorb and ionize analytes enriched on the probe surface for electrospray ionization mass spectrometric (ESI-MS) analysis under ambient and open-air conditions. The method showed good linearity, with correlation coefficient values (r2) no less than 0.9904, and the calibration function was verified via Mandel's fitting test (p > 0.063). The limits of detection were in the range of 0.003-0.05, 1.1-5.1, and 1.9-15.8 ng/g for analysis of drinking water, honey, and milk samples, respectively. Recoveries of the five targeted macrolide antibiotics in honey and milk samples ranged from 73.4% to 98.1%, with the standard deviations no higher than 8.6%. As a result, MIP-coated wooden-tip ESI-MS method could be feasibly used as a sensitive method for determination of trace macrolide antibiotics in complex food samples.

Experimental investigation on the migration of leachate under flowing conditions through laboratory ERT.

With an increase of service time of landfills, a great amount of old landfills begin to leak and the leachate impairs the surrounding environment severely. Defining the flow of leachate is significant to the monitoring and restoration of the landfill. Field tests and laboratory tests are often used to investigate the leachate flow. However, many uncontrollable factors may affect the accuracy of field tests, and the application of field test results is usually limited. At the same time, it is difficult to simulate and monitor the migration process of leachate in real time in laboratory. To address this problem, a new physical simulating device is created to simulate the leachate migration under flowing conditions, and improved ERT device is designed to monitor the migration in laboratory tests. The results show that the improved ERT could delineate the migration range well in laboratory tests, providing a new method to investigate the leachate migration in laboratory test and providing a reference to the application of ERT in field tests. The relative variation rate of resistivity could reduce the influence of background, and is very suitable for time-lapse ERT. In addition, the effect of flowing rate, leakage rate, and time on the leachate migration is also investigated. The results show that the horizontal migration rate increases with an increase of flowing rate. The leakage rate has a significant influence on the vertical migration, but has limited effect on the horizontal migration. The curvature of migration front increases with an increase of flowing rate and time.

Coupling Paternò-Büchi Reaction with Surface-Coated Probe Nanoelectrospray Ionization Mass Spectrometry for In Vivo and Microscale Profiling of Lipid C═C Location Isomers in Complex Biological Tissues.

Lipids are important structural components of biological systems, and lipid C═C locations play important roles in their biophysical and biochemical properties. Rapid, in vivo, in situ, and microscale lipidomics investigation (including precise identification of lipid C═C locations and isomers) of biological specimen has great potential for clinical diagnosis, biological studies, and biomarker discovery. Here we report a novel lipidomics methodology by coupling Paternò-Büchi (PB) reaction with surface-coated probe nanoelectrospray ionization mass spectrometry (SCP-nanoESI-MS) for in vivo, in situ, and microscale analysis of lipid species and C═C location isomers in complex biological tissues. The proposed SCP-PB-nanoESI-MS method was performed by application of a biocompatible solid-phase microextraction (SPME) probe for in vivo, in situ, and microscale sampling and extraction of lipids from biological tissues, and then some spray solvent containing PB reagent was applied to desorb lipid species enriched on SPME probe within a nanospray tip. Subsequently, ultraviolet irradiation was employed to initiate PB reaction for unsaturated lipids within the nanospray tip. After that, a high voltage was applied on the SPME probe to induce nanoESI for MS analysis under ambient and open-air conditions, and collision-induced dissociation was performed to the PB reaction product ions for determination of lipid C═C locations and isomers. By using our proposed SCP-BP-nanoESI-MS method, microscale investigation of lipid compositions and C═C location isomers for lipid droplet of Perilla seed and human intestinal tissue were successfully achieved, and in vivo analysis of lipid species and C═C locations for zebrafish was accomplished.

The interaction between Vav1 and EBNA1 promotes survival of Burkitt's lymphoma cells by down-regulating the expression of Bim.

Vav1 is a guanine nucleotide exchange factor (GEF) predominantly expressed in hematopoietic cells, and functions in the development and antigen-stimulated response of lymphocytes. Burkitt's lymphoma (BL) is characterized as transformed B cell lymphoma, and is highly associated with Epstein-Barr virus (EBV). EBV nuclear antigen 1 (EBNA1) is the only viral protein expressed across all three types of latency and essential for the persistence of EBV genome. It is not clear yet how EBNA1 contributes to the growth advantage of latently infected cells such as in EBV+ lymphoma B cells. Here, we reported that Vav1 interacts with EBNA1 via its C-terminal SH3 domain. This interaction suppresses the expression of a pro-apoptotic Bcl-2 family member, Bim, resulting in the resistance of the BL cells to apoptotic inductions. Our data uncovered Vav1 as a novel target for EBNA1, and suggested a pro-survival role of Vav1 in the pathogenesis of EBV associated BLs.