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Lung squamous cell carcinoma (LSCC) is a deadly cancer in the world. Histone demethylase Jmjd2c is a key epigenetic regulator in various tumors, while the molecular mechanism underlying Jmjd2c regulatory in LSCC is still unclear. We used the aldehyde dehydrogenasebright (ALDHbri+) subtype as a research model for cancer stem cells (CSCs) in LSCC and detected the sphere formation ability and the proportion of ALDHbri+ CSCs with Jmjd2c interference and caffeic acid (CA) treatment. Additionally, we carried out bioinformatic analysis on the expression file of Jmjd2c RNAi mice and performed western blotting, qRT-PCR, Co-IP and GST pull-down assays to confirm the bioinformatic findings. Moreover, we generated Jmjd2c-silenced and Jmjd2c-SOX2-silenced ALDHbri+ tumor-bearing BALB/c nude mice to detect the effects on tumor progression. The results showed that Jmjd2c downregulation inhibited the sphere formation and the proportion of ALDHbri+ CSCs. The SOX2 decreased expression significantly in Jmjd2c RNAi mice, and they were positively co-expressed according to the bioinformatic analysis. In addition, SOX2 expression decreased in Jmjd2c shRNA ALDHbri+ CSCs, Jmjd2c and SOX2 proteins interacted with each other. Furthermore, Jmjd2c interference revealed significant blocking effect, and Jmjd2c-SOX2 interference contributed even stronger inhibition on ALDHbri+ tumor progression. The Jmjd2c and SOX2 levels were closely related to the development and prognosis of LSCC patients. This study indicated that Jmjd2c played key roles on maintaining ALDHbri+ CSC activity in LSCC by interacting with transcription factor SOX2. Jmjd2c might be a novel molecule for therapeutic targets and biomarkers in the diagnosis and clinical treatment of lung cancer.
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Carcinoma de Células Escamosas , Histona Demetilasas con Dominio de Jumonji , Neoplasias Pulmonares , Células Madre Neoplásicas , Factores de Transcripción SOXB1 , Animales , Femenino , Humanos , Masculino , Ratones , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Histona Demetilasas con Dominio de Jumonji/metabolismo , Histona Demetilasas con Dominio de Jumonji/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamiento farmacológico , Ratones Endogámicos BALB C , Ratones Desnudos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Factores de Transcripción SOXB1/metabolismo , Factores de Transcripción SOXB1/genéticaRESUMEN
South and Southeast Asia (SSA) emitted black carbon (BC) exerts potential effects on glacier and snow melting and regional climate change in the Tibetan Plateau. In this study, online BC measurements were conducted for 1 year at a remote village located at the terminus of the Mingyong Glacier below the Meili Snow Mountains. The Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) was used to investigate the contribution and potential effect of SSA-emitted BC. In addition, variations in the light absorption characteristics of BC and brown carbon (BrC) were examined. The results indicated that the annual mean concentration of BC was 415 ± 372 ngm-3, with the highest concentration observed in April (monthly mean: 930 ± 484 ngm-3). BC exhibited a similar diurnal variation throughout the year, with two peaks observed in the morning (from 8:00 to 9:00 AM) and in the afternoon (from 4:00 to 5:00 PM), with even lower values at nighttime. At a short wavelength of 370 nm, the absorption coefficient (babs) reached its maximum value, and the majority of babs values were < 20 Mm-1, indicating that the atmosphere was not overloaded with BC. At the same wavelength, BrC substantially contributed to babs, with an annual mean of 25.2 % ± 12.8 %. SSA was the largest contributor of BC (annual mean: 51.1 %) in the study area, particularly in spring (65.6 %). However, its contributions reached 20.2 % in summer, indicating non-negligible emissions from activities in other regions. In the atmosphere, the SSA BC-induced radiative forcing (RF) over the study region was positive. While at the near surface, the RF exhibited a significant seasonal variation, with the larger RF values occurring in winter and spring. Overall, our findings highlight the importance of controlling BC emissions from SSA to protect the Tibetan Plateau against pollution-related glacier and snow cover melting.
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BACKGROUND: Whether hyperbaric oxygen therapy (HBOT) can cause paradoxical herniation is still unclear. CASE SUMMARY: A 65-year-old patient who was comatose due to brain trauma underwent decompressive craniotomy and gradually regained consciousness after surgery. HBOT was administered 22 d after surgery due to speech impairment. Paradoxical herniation appeared on the second day after treatment, and the patient's condition worsened after receiving mannitol treatment at the rehabilitation hospital. After timely skull repair, the paradoxical herniation was resolved, and the patient regained consciousness and had a good recovery as observed at the follow-up visit. CONCLUSION: Paradoxical herniation is rare and may be caused by HBOT. However, the underlying mechanism is unknown, and the understanding of this phenomenon is insufficient. The use of mannitol may worsen this condition. Timely skull repair can treat paradoxical herniation and prevent serious complications.
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BACKGROUND: Autologous fat transplantation, widely used in cosmetic and reparative surgery for volumetric enhancements, faces challenges with its inconsistent long-term survival rates. The technique's efficacy, crucial for its development, is hindered by unpredictable outcomes. Enriching fat grafts with adipose-derived stem cells (ADSCs) shows promise in improving survival efficiency. OBJECTIVES: This study aimed to explore the potential of receptor-interacting protein kinase 3 (RIP3) kinase inhibitors as a pretreatment for ADSCs in enhancing autologous fat graft retention over a long term. METHODS: ADSCs were isolated, cultured under normal or oxygen-glucose deprivation conditions, and mixed with particulate fat grafts to form distinct experimental groups in female nude mice. Fat graft mass and volume, along with underlying mechanisms, were evaluated using quantitative reverse transcription polymerase chain reaction (RT-qPCR), immunohistochemistry, and Western blot analysis. RESULTS: The experimental group, pretreated with RIP3 kinase inhibitors, had higher graft mass and volume, greater adipocyte integrity, and increased peroxisome proliferator-activated receptor gamma (PPARγ) mRNA levels than control groups. Furthermore, the experimental group demonstrated lower expression of necroptosis pathway proteins in the short term and an ameliorated inflammatory response as indicated by interleukin-1 beta (IL-1ß), interleukin-10 (IL-10) mRNA levels, and histological analyses. Notably, enhanced neovascularization was evident in the experimental group. CONCLUSIONS: These findings suggest that RIP3 kinase inhibitor pretreatment of ADSCs can improve fat graft survival, promote adipocyte integrity, potentially decrease inflammation, and enhance neovascularization. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. 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 .
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BACKGROUND: Breast cancer is a commonly diagnosed cancer worldwide. Human MutT homolog 1 (MTH1) is found to be elevated in breast tumors and cancer cells need MTH1 for survival. Pharmacological inhibition of MTH1 may be potentially beneficial in the treatment of breast cancer. METHODS: MA-24 was screened by malachite green colorimetric assay for MTH1 inhibitors and the kinetic characteristics of MA-24 were assessed. The features of MA-24's binding with MTH1 were ascertained through molecular docking, and the cytotoxic activity of MA-24 was validated in vitro and in vivo. Target engagement assays, comet assay, and Western blot confirmed the intracellular target and mechanism of MA-24. RESULTS: MA-24 shows potent antitumor bioactivity both in vitro and in vivo. MA-24 competitively inhibited the MTH1 and further induced DNA strand breaks, leading to increased apoptosis of cancer cells depending on the upregulation of the cleaved-caspase 3-cleaved-PARP axis. In particular, MA-24 exhibited a powerful efficacy and safety in vivo (tumor growth inhibition rate: 61.8%). CONCLUSIONS: MA-24 possesses a broad spectrum of breast cancer cytotoxicity and offered valuable insights for overcoming the challenges of chemotherapy-related toxicity, which holds great potential for the further development MA-24 as an anti-cancer drug.
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Food safety represents a critical global public health issue, with safety challenges posed by foodborne pathogens garnering extensive attention. Therefore, we introduce a co-recognition, enrichment and sensing (CES) all-in-one strategy for analysis of bacteria with low background and high specificity. This method employs antimicrobial peptide (AMP) functionalized magnetic nanoparticles (MNPs) to enrich bacteria and uses aptamer@Au@PBA (KxMFe(CN)6 (M = Pb and Ni)) NPs as silent SERS tags. When both S. aureus and E. coli O157:H7 are present, the silent SERS probes could specifically label the target bacteria, forming a sandwich-like structure. This binding induces silent Raman shifts (2139 cm-1 and 2197 cm-1), enabling quantification of two bacteria. Coupling with the modular flexible microfluidics and magnetic control slider device, this platform facilitates rapid switching between magnetic loading and elution. The CES SERS method demonstrated linear relationships for both S. aureus and E. coli O157:H7 at 50-1600 cfu mL-1, with detection limits of 14 and 18 cfu mL-1, respectively. The method achieved recovery rates of 85.6-112% and relative standard deviations of 1.5-8.6%. Validation using the ELISA method revealed relative errors between -7.5 and 4.3%. The CES approach has potential applications in food safety, environmental monitoring, and biomedical diagnosis.
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Técnicas Biosensibles , Nanopartículas del Metal , Nanopartículas del Metal/química , Staphylococcus aureus , Escherichia coli , Microfluídica , Técnicas Biosensibles/métodos , Bacterias , Fenómenos Magnéticos , Espectrometría Raman/métodos , Oro/químicaRESUMEN
Background: The application of chimeric antigen receptor (CAR) NK cells in solid tumors is hindered by lack of tumor-specific targets and inefficient CAR-NK cell efficacy. Claudin-6 (CLDN6) has been reported to be overexpressed in ovarian cancer and may be an attractive target for CAR-NK cells immunotherapy. However, the feasibility of using anti-CLDN6 CAR-NK cells to treat ovarian cancer remains to be explored. Methods: CLDN6 expression in primary human ovarian cancer, normal tissues and cell lines were detected by immunohistochemistry and western blot. Two types of third-generation CAR NK-92MI cells targeting CLDN6, CLDN6-CAR1 NK-92MI cells with domains containing self-activated elements (NKG2D, 2B4) and CLDN6-CAR2 NK-92MI cells with classical domains (CD28, 4-1BB) were constructed by lentivirus transfection, sorted by flow cytometry and verified by western blot and qPCR. OVCAR-3, SK-OV-3, A2780, Hey and PC-3 cells expressing the GFP and luciferase genes were transduced. Subcutaneous and intraperitoneal tumor models were established via NSG mice. The ability of CLDN6-CAR NK cells to kill CLDN6-positive ovarian cancer cells were evaluated in vitro and in vivo by live cell imaging and bioluminescence imaging. Results: Both CLDN6-CAR1 and CLDN6-CAR2 NK-92MI cells could specifically killed CLDN6-positive ovarian cancer cells (OVCAR-3, SK-OV-3, A2780 and Hey), rather than CLDN6 negative cell (PC-3), in vitro. CLDN6-CAR1 NK-92MI cells with domains containing self-activated elements (NKG2D, 2B4) exhibited stronger cytotoxicity than CLDN6-CAR2 NK-92MI cells with classical domains (CD28, 4-1BB). Furthermore, CLDN6-CAR1 NK cells could effectively eliminate ovarian cancer cells in subcutaneous and intraperitoneal tumor models. More importantly, CAR-NK cells combined with immune checkpoint inhibitors, anti-PD-L1, could synergistically enhance the antitumor efficacy of CLDN6-targeted CAR-NK cells. Conclusions: These results indicate that CLDN6-CAR NK cells possess strong antitumor activity and represent a promising immunotherapeutic modality for ovarian cancer.
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Claudinas , Neoplasias Ováricas , Receptores Quiméricos de Antígenos , Humanos , Animales , Ratones , Femenino , Receptores Quiméricos de Antígenos/genética , Neoplasias Ováricas/terapia , Neoplasias Ováricas/metabolismo , Línea Celular Tumoral , Apoptosis , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Antígenos CD28/metabolismo , Células Asesinas Naturales , Inmunoterapia/métodos , Inmunoterapia Adoptiva/métodosRESUMEN
The combined application of nanozymes and surface-enhanced Raman scattering (SERS) provides a promising approach to obtain label-free detection. However, developing nanomaterials with both highly efficient enzyme-like activity and excellent SERS sensitivity remains a huge challenge. Herein, we proposed one-step synthesis of Mo2N nanoparticles (NPs) as a "two-in-one" substrate, which exhibits both excellent peroxidase (POD)-like activity and high SERS activity. Its mimetic POD activity can catalyze the 3,3',5,5'-tetramethylbenzidine (TMB) molecule to SERS-active oxidized TMB (ox-TMB) with high efficiency. Furthermore, combining experimental profiling with theory, the mechanism of POD-like activity and SERS enhancement of Mo2N NPs was explored in depth. Benefiting from the outstanding properties of Mo2N NPs, a versatile platform for indirect SERS detection of biomarkers was developed based on the Mo2N NPs-catalyzed product ox-TMB, which acts as the SERS signal readout. The feasibility of this platform was validated using glutathione (GSH) and target antigens alpha-fetoprotein antigen (AFP) and carcinoembryonic antigen (CEA) as representatives of small molecules with a hydroxyl radical (·OH) scavenging effect and proteins with a low Raman scattering cross-section, respectively. The limits of detection of GSH, AFP, and CEA were as low as 0.1 µmol/L, 89.1, and 74.6 pg/mL, respectively. Significantly, it also showed application in human serum samples with recoveries ranging from 96.0 to 101%. The acquired values based on this platform were compared with the standard electrochemiluminescence method, and the relative error was less than ±7.3. This work not only provides a strategy for developing highly active bifunctional nanomaterials but also manifests their widespread application for multiple biomarkers analysis.
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The lockdowns implemented during the coronavirus disease 2019 (COVID-19) pandemic provide a unique opportunity to investigate the impact of emission sources and meteorological conditions on the trans-boundary transportation of black carbon (BC) aerosols to the Tibetan Plateau (TP). In this study, we conducted an integrative analysis, including in-situ observational data, reanalysis datasets, and numerical simulations, and found a significant reduction in the trans-boundary transport of BC to the TP during the 2020 pre-monsoon season as a result of the lockdowns and restrictive measures. Specifically, we observed a decrease of 0.0211 µgm-3 in surface BC concentration over the TP compared to the 2016 pre-monsoon period. Of this reduction, approximately 6.04 % can be attributed to the decrease in emissions during the COVID-19 pandemic, surpassing the 4.47 % decrease caused by changes in meteorological conditions. Additionally, the emission reductions have weakened the trans-boundary transport of South Asia BC to the TP by 0.0179 µgm-2s-1; indicating that the recurring spring atmospheric pollution from South Asia to the TP will be alleviated through the reduction of anthropogenic emissions. Moreover, it is important to note that BC deposition on glaciers contributes significantly to glacier melting due to its enrichment, posing a threat to the water sustainability of the TP. Therefore, urgent measures are needed to reduce emissions from adjacent regions to preserve the TP as the "Asian Water Tower."
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Contaminantes Atmosféricos , COVID-19 , Humanos , Tibet/epidemiología , Pandemias , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , COVID-19/epidemiología , Control de Enfermedades Transmisibles , Aerosoles y Gotitas Respiratorias , Hollín/análisis , Carbono/análisis , Agua/análisisRESUMEN
Electrolysis for producing hydrogen powered by renewable electricity can be dramatically expanded by adapting different electrolytes (brine, seawater or pure water), which means the anode materials must stand up to complex electrolyte conditions. Here, a novel catalyst/support hybrid of binary Ru3.5Ir1Ox supported by barium strontium sulfate (BaSrSO4) was synthesized (RuIrOx/BSS) by exchanging the anion ligands of support. The as-synthesized RuIrOx/BSS exhibits compelling oxygen evolution (OER) and chlorine evolution (CER) performances, which affords to 10 mA cm-2 with only overpotential of 244 mV and 38 mV, respectively. The performed X-ray adsorption spectra clearly indicate the presence of an interface charge transfer effect, which results in the assignment of more electrons to the d orbitals of the Ru and Ir sites. The theoretical calculations demonstrated that the electronic structures of the catalytic active sites were modulated to give a lower overpotential, confirming the intrinsically high OER and CER catalytic activity.
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Invasive aspergillosis (IA) is a severe disease, the pathogenesis of which remains unclear. The present study aimed to determine the molecular mechanism of IA and to identify potential biomarkers using bioinformatics analysis. The GSE78000 dataset, which includes data from patients with IA and healthy individuals, was downloaded from Gene Expression Omnibus. Differentially expressed genes (DEGs) between the IA and control groups were identified with the 'affy' package in R software. The Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) databases were then used to analyse the function and pathway enrichment of DEGs. The protein-protein interaction network was analysed with the Search Tool for the Retrieval of Interacting Genes (STRING) website. In addition, DEGs were confirmed using reverse transcription-quantitative PCR and western blotting in samples with IA (n=6) and control samples (n=6) collected from the Department of Respiratory and Critical Care Medicine of the First Affiliated Hospital of Henan University of Science and Technology (Luoyang, China). The present study identified 735 DEGs, including 312 upregulated and 423 downregulated genes. Through GO and KEGG analyses of the DEGs, macrophage activation and hypoxia-inducible factor 1 (HIF-1) signalling pathways were revealed to be significantly upregulated and downregulated, respectively, in patients with IA compared with that of the healthy individuals. Subsequently, correlation analysis of macrophage activation and HIF-1 signalling pathways was revealed using correlation as a distance metric for hierarchical clustering correlation analysis. However, there was no protein-protein interaction between the macrophage activity regulation and HIF-1 signalling pathways based on STRING analysis. In summary, the present study identified candidate genes and associated molecules that may be associated to IA and revealed potential biomarkers and therapeutic targets for IA.
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In enantiomer recognition and separation, a highly enantioselective approach with universal applicability is urgently desired but hard to realize, especially in the case of chiral molecules. To resolve the trade-off between enantioselectivity and universality, a glutathione (GSH) and methylated cyclodextrins (MCD)-functionalized covalent organic framework (GSH-MCD COF) with porosity and abundant chiral surfaces is presented that was designed and synthesized for recognition and separation of various enantiomers. As expected, the GSH-MCD COF can be used as chiral stationary phases for the separation of various enantiomers, including aromatic alcohols, aromatic acids, amides, amino acids, and organic acids, with performance and versatility even superior to some widely used commercial chiral chromatographic columns. Furthermore, the synthesized GSH-MCD COF shows high enantioselectivity for the rapid recognition and identification of enantiomers and chiral metabolites when coupling to Raman spectroscopy. Molecular simulations suggest that the COF provides a confined microenvironment for cyclodextrins and peptides that dictates the separation and recognition capability. This work provides a strategy to synthesize synergetic multichiral COF and achieve separations and recognitions of enantiomers in complex samples.
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PURPOSE: This study aimed to compare the effect of gonadotropin-releasing hormone agonist (GnRHa) trigger alone versus dual trigger comprising GnRHa and low-dose human chorionic gonadotropin (hCG) on reproductive outcomes in patients with polycystic ovary syndrome (PCOS) who received the freeze-all strategy. METHODS: A total of 615 cycles were included in this retrospective cohort study. Propensity score matching (PSM) was performed to control potential confounding factors between GnRHa-trigger group (0.2 mg GnRHa) and dual-trigger group (0.2 mg GnRHa plus 1000/2000 IU hCG) in a 1:1 ratio. Multivariate logistic regression was applied to estimate the association between trigger methods and reproductive outcomes. RESULTS: After PSM, patients with dual trigger (n = 176) had more oocytes retrieved, mature oocytes, and 2PN embryos compared to that with GnRHa trigger alone. However, the oocytes maturation rate, normal fertilization rate, and frozen embryos between the two groups were not statistically different. The incidence of ovarian hyperstimulation syndrome (OHSS) (14.8% vs. 2.8%, P < 0.001) and moderate/severe OHSS (11.4% vs. 1.7%, P < 0.001) were significantly higher in dual-trigger group than in GnRHa-alone group. Logistic regression analysis showed the adjusted odds ratio of dual trigger was 5.971 (95% confidence interval 2.201-16.198, P < 0.001) for OHSS. The pregnancy and single neonatal outcomes were comparable between the two groups (P > 0.05). CONCLUSION: For PCOS women with freeze-all strategy, GnRHa trigger alone decreased the risk of OHSS without damaging oocyte maturation and achieved satisfactory pregnancy outcomes.
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Síndrome de Hiperestimulación Ovárica , Síndrome del Ovario Poliquístico , Embarazo , Recién Nacido , Humanos , Femenino , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Fertilización In Vitro/métodos , Inducción de la Ovulación/métodos , Estudios Retrospectivos , Puntaje de Propensión , Hormona Liberadora de Gonadotropina/farmacología , Gonadotropina Coriónica/farmacología , Síndrome de Hiperestimulación Ovárica/epidemiología , Síndrome de Hiperestimulación Ovárica/prevención & control , Oocitos , Índice de EmbarazoRESUMEN
Supramolecular macrocycle-based covalent organic frameworks (COFs) are promising adsorbents for adsorption of hazards due to their host-guest recognition property. However, most supramolecular macrocycles are conformationally flexible, making them challenging to introduce into COFs. In this work, a calix[6]arene-based COF (CX6-BD COF) was fabricated with a unique flower-like morphology and high crystallinity. Especially, the cavity of CX6 exhibited host-guest inclusion interaction for sulfonamides (SAs), which was verified by quantum chemistry calculation. The integration of the porosity of COFs with the recognition cavity of CX6 made CX6-BD COF display excellent enrichment performance for SAs, with good enrichment factors (EFs) between 77 and 96. The material was employed as an adsorbent for COF membrane filter extraction, coupled with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) to simultaneously enrich and determine seven SAs in animal-derived food. The analytical method showed a wide linear range (0.01-100 µg/L and 0.05-100 µg/L) and low detection limits (3-10 ng/L). The established method was successfully applied to sensitively determine SAs in chicken, pork and beef samples, which achieved satisfactory recoveries (73.8-113%). These results demonstrated CX6-BD COF has good application potential in determination of trace and ultra-trace SAs in complex food matrices as an adsorbent.
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Estructuras Metalorgánicas , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Estructuras Metalorgánicas/química , Espectrometría de Masas en Tándem , Sulfonamidas/análisis , Extracción en Fase Sólida/métodos , Sulfanilamida/análisis , Límite de DetecciónRESUMEN
In order to reduce the impact of greenhouse gases on the environment, the development of various new CO2 capture materials has become a hot spot. In this work, a novel composite amine solid adsorbent was prepared by simultaneously using tetraethylenepentamine (TEPA) and 2-[2-(dimethylamino) ethoxy] ethanol (DMAEE) for amine functionalization on the polyester microsphere carrier. The introduction of methyl methacrylate (MMA) with high glass transition temperature into the polyester carrier makes the carrier microspheres have high hardness. At the same time, the carrier also contains active epoxy groups and hydrophobic glycidyl methacrylate (GMA, which can undergo ring-opening reaction with composite amines to achieve high-load and low-energy chemical grafting of amines on the carrier. The composite aminated polyester microspheres were used as an efficient adsorbent for CO2 in simulated flue gas. The results show that the synergistic effect of TEPA-DMAEE composite amine system in the adsorbent is beneficial to the improvement of CO2 capture capacity. When the total amine content in the impregnating solution is 45 wt% and the composite amine ratio is TEPA: DMAEE = 6: 4, the CO2 adsorption capacity can reach the optimal value of 2.45 mmol/ g at 70 °C. In addition, the composite amine microsphere adsorbent has cyclic regeneration performance. Importantly, through kinetic fitting, the Avrami kinetic model fits the CO2 adsorption better than the quasi-first-order and quasi-second-order kinetic models, which proves that physical adsorption and chemical adsorption coexist in the adsorption process. This simple, long-term stable and excellent selective separation performance makes amine-functionalized adsorbents have potential application prospects in CO2 capture.
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Aminas , Dióxido de Carbono , Éteres de Etila , Etilenodiaminas , Aminas/química , Dióxido de Carbono/química , Microesferas , Poliésteres , TrietilenofosforamidaRESUMEN
Improving the sensitivity and reproducibility of surface-enhanced Raman spectroscopy (SERS) methods for the detection of bioactive molecules is crucial in biological process research and clinical diagnosis. Herein, we designed a novel SERS platform for cardiac troponin I (cTnI) detection by a chemical-chemical redox cycle signal amplification strategy combined with a dual ratiometric immunoassay. First, ascorbic acid (AA) was generated by enzyme-assisted immunoreaction with a cTnI-anchored sandwich structure. Then, oxidized 4-mercaptophenol (ox4-MP) was reacted with AA to produce 4-mercaptophenol (4-MP). Quantitative analysis of cTnI was realized by a Raman signal switch between ox4-MP and 4-MP. Specifically, AA could be regenerated by reductant (tris(2-carboxyethyl) phosphine, TCEP), which in turn produced more signal indicator 4-MP, causing significant signal amplification for cTnI analysis by SERS immunosensing. Moreover, a dual ratiometric-type SERS method was established with the intensity ratio I1077/I822 and I633/I822, which improved the reproducibility of the cTnI assay. The excellent performance of the chemical-chemical redox cycle strategy and ratio-type SERS assay endows the method with high sensitivity and reproducibility. The linear ranges of cTnI were 0.001 to 50.0 ng mL-1 with detection limits of 0.33 pg mL-1 (upon I1077/I822) and 0.31 pg mL-1 (upon I635/I822), respectively. The amount of cTnI in human serum samples yielded recoveries from 89.0 to 114%. This SERS method has remarkable analytical performance, providing an effective approach for the early diagnosis of cardiovascular diseases, and has great latent capacity in the sensitive detection of bioactive molecules.
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Técnicas Biosensibles , Nanopartículas del Metal , Humanos , Espectrometría Raman/métodos , Troponina I , Límite de Detección , Reproducibilidad de los Resultados , Inmunoensayo/métodos , Oxidación-Reducción , Nanopartículas del Metal/química , Oro/químicaRESUMEN
Nickel-iron (oxy)hydroxides (NiFeOxHy) have been validated to speed up sluggish kinetics of the oxygen evolution reaction (OER) but still lack satisfactory substrates to support them. Here, non-stoichiometric blue titanium oxide (B-TiOx) was directly derived from Ti metal by alkaline anodization and used as a substrate for electrodeposition of amorphous NiFeOxHy (NiFe/B-TiOx). The performed X-ray absorption spectroscopy (XAS) and density functional theory (DFT) calculations evidenced that there is a charge transfer between B-TiOx and NiFeOxHy, which gives rise to an elevated valence at the Ni sites (average oxidation state â¼ 2.37). The synthesized NiFe/B-TiOx delivers a current density of 10 mA cm-2 and 100 mA cm-2 at an overpotential of 227 mV and 268 mV, respectively, which are better than that of pure Ti and stainless steel. It also shows outstanding activity and stability under industrial conditions of 6 M KOH. The post-OER characterization studies revealed that the surface morphology and valence states have no significant change after 24 h of operation at 500 mA cm-2, and also can effectively inhibit the leaching of Fe. We illustrate that surface modification of Ti which has high corrosion resistance and mechanical strength, to generate strong interactions with NiFeOxHy is a simple and effective strategy to improve the OER activity and stability of non-precious metal electrodes.
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Environmental pollution, especially agricultural carbon emissions (ACE), has led to public health problems to rural areas in China and accompanied by a heavy medical economic burden. However, most studies on carbon dioxide emissions and healthcare expenditures focused on the industrial sector, and the effect of ACE was overlooked. Therefore, studying the effect of ACE on rural residents' healthcare expenditures (NHCE) is not only conducive to accelerating the low-carbon transformation of agriculture but also has important implications for reducing healthcare expenditures. In addition, the effect of ACE on NHCE in different areas might be complex and nonlinear due to differences in years of schooling (EDU) leading to different awareness of environmental protection and health among farmers. Therefore, this paper used the Bayesian quantile regression (BQR) model and the panel threshold model to explore the effect of ACE on NHCE in different areas, based on the panel data of 31 provinces in China from 2007 to 2019. The results showed that ACE and NHCE experienced similar spatial distribution from 2007 to 2019. The BQR estimation results found that ACE had a significant positive effect on NHCE at different quantile levels during the sample period, public health concern, and thereby increasing the medical and economic burden of rural households. Meanwhile, ACE had a positive effect on NHCE with a significant single threshold effect from EDU. Specifically, farmers gradually realize the harm of environmental pollution to health with the continuous improvement of education level, and then ACE aggravated the improvement of NHCE after exceeding the threshold. EDU was more essential for farmers in contiguous poverty (CP) areas than in relatively developed (RD) areas and played an important role between ACE and NHCE. Furthermore, demographic structure, economic development, and public services were also positive driving factors for NHCE. The results of analysis provide a valuable reference for understanding the factors influencing NHCE and enable formulation of ACE emission reduction policies according to local conditions.
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Agricultores , Gastos en Salud , Humanos , Teorema de Bayes , Agricultura , Dióxido de Carbono/análisis , Desarrollo Económico , Escolaridad , ChinaRESUMEN
Long-term ingestion or exposure to food contaminated with per- and polyfluoroalkyl substances (PFASs) may cause potential harm to human health. Due to the low contents of PFASs in complex food matrices, it is of great significance to develop adsorbents with excellent properties to enrich PFASs before analysis. Herein, calix[4]arene (CX4) was used as building block to prepare ordered crystalline covalent organic frameworks (COFs). The perfect combination of the host-guest recognition ability of CX4 and the porosity of COFs makes the CX4-COFs selective and high adsorption capacity for linear molecular PFASs (261-1055 mg/g). The adsorption behavior and mechanism were verified by isotherm adsorption experiments and simulation calculations. The CX4-COFs were then used as adsorbents for membrane solid-phase extraction (M-SPE), combined with ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) to determine PFASs in food. The method has low detection limits (0.11-0.28 ng/kg) and good precision (1.3%-9.8%), and has been successfully applied to the simultaneous enrichment and determination of six PFASs in fish, shrimp and shellfish. Satisfactory recoveries (79.9%-118%) were obtained. This study provides a new strategy for preparing CX4-COFs containing macrocyclic molecules with different morphologies and expands the application of COFs as attractive enrichment media for sample pretreatment.
Asunto(s)
Fluorocarburos , Estructuras Metalorgánicas , Animales , Humanos , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Estructuras Metalorgánicas/química , Adsorción , Alimentos Marinos/análisis , Fluorocarburos/análisis , Extracción en Fase Sólida/métodos , Límite de DetecciónRESUMEN
As an E3 ubiquitin ligase, F-box and leucine-rich repeat protein 5 (FBXL5) participates in diverse biologic processes. However, the role of Fbxl5 in mouse oocyte meiotic maturation has not yet been fully elucidated. The present study revealed that mouse oocytes depleted of Fbxl5 were unable to complete meiosis, as Fbxl5 silencing led to oocyte meiotic failure with reduced rates of GVBD and polar body extrusion. In addition, Fbxl5 depletion induced aberrant mitochondrial dynamics as we noted the overproduction of reactive oxygen species (ROS) and the accumulation of phosphorylated γH2AX with Fbxl5 knockdown. We also found that Fbxl5-KD led to the abnormal accumulation of CITED2 proteins in mouse oocytes. Our in vitro ubiquitination assay showed that FBXL5 interacted with CITED2 and that it mediated the degradation of CITED2 protein through the ubiquitination-proteasome pathway. Collectively, our data revealed critical functions of FBXL5 in redox hemostasis and spindle assembly during mouse oocyte maturation.