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Artificial ion channel membranes hold high promise in water treatment, nanofluidics, and energy conversion, but it remains a great challenge to construct such smart membranes with both reversible ion-gating capability and desirable ion selectivity. Herein, we constructed a smart MXene-based membrane via p-phenylenediamine functionalization (MLM-PPD) with highly stable and aligned two-dimensional subnanochannels, which exhibits reversible ion-gating capability and ultrahigh metal ion selectivity similar to biological ion channels. The pH-sensitive groups within the MLM-PPD channel confers excellent reversible Mg2+-gating capability with a pH-switching ratio of up to 100. The mono/divalent metal-ion selectivity up to 1243.8 and 400.9 for K+/Mg2+ and Li+/Mg2+, respectively, outperforms other reported membranes. Theoretical calculations combined with experimental results reveal that the steric hindrance and stronger PPD-ion interactions substantially enhance the energy barrier for divalent metal ions passing through the MLM-PPD, and thus leading to ultrahigh mono/divalent metal-ion selectivity. This work provides a new strategy for developing artificial-ion channel membranes with both reversible ion-gating functionality and high-ion selectivity for various applications.
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Canais Iônicos , Metais , Nitritos , Elementos de Transição , Íons , Cátions Bivalentes , Membranas Artificiais , Concentração de Íons de HidrogênioRESUMO
Efficient capture of 99TcO4- is the focus in nuclear waste management. For laboratory operation, ReO4- is used as a nonradioactive alternative to 99TcO4- to develop high-performance adsorbents for the treatment. However, the traditional design of new adsorbents is primarily driven by the chemical intuition of scientists and experimental methods, which are inefficient. Herein, a machine learning (ML)-assisted material genome approach (MGA) is proposed to precisely design high-efficiency adsorbents. ML models were developed to accurately predict adsorption capacity from adsorbent structures and solvent environment, thus predicting and screening the 2450 virtual pyridine polymers obtained by MGA, and it was found that halogen functionalization can enhance its adsorption efficiency. Two halogenated functional pyridine polymers (F-C-CTF and Cl-C-CTF) predicted by this approach were synthesized that exhibited excellent acid/alkali resistance and selectivity for ReO4-. The adsorption capacity reached 940.13 (F-C-CTF) and 732.74 mg g-1 (Cl-C-CTF), which were better than those of most reported adsorbents. The adsorption mechanism is comprehensively elucidated by experiment and density functional theory calculation, showing that halogen functionalization can form halogen-bonding interactions with 99TcO4-, which further justified the theoretical plausibility of the screening results. Our findings demonstrate that ML-assisted MGA represents a paradigm shift for next-generation adsorbent design.
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PURPOSE: To enhance the understanding of histological healing after repairing medial meniscal posterior root tear (MMPRT) at an early stage, utilizing a goat model. METHODS: Eighteen adult goats, totaling thirty-six knee joints, were allocated into three groups (n = 12): Sham group (Sham), Root Tear group (RT), and Root Tear with Transosseous Suture group (RTS). At 12- and 24-week intervals post-surgery, all the knees were harvested for imaging, macroscopic, histological, and biomechanical assessments. RESULTS: The intact root served as a meniscus-bone interface which connected the tibial and the circular fibers of the meniscus, with a bony insertion and a root-meniscus transition. A direct-fibrous-connection displayed at the bony insertion proximal to the synovium in the RTS group, while the remaining regions of the root displayed indirect-fibrous healing. The healing in the RT group was disjointed and reminiscent of scar tissue. The RTS group exhibited a more pronounced coronal extrusion compared to the Sham group (0.42 ± 0.09 vs. 0.19 ± 0.02, P = 0.0012) but was improved relative to that of the RT group (0.49 ± 0.02, P = 0.0028). The failure load and stiffness of the RTS group were notably higher than those of the RT group, with a strength of 42.67% and a stiffness of 83.75% of the intact root. All the samples ruptured at the root-meniscus transitions. CONCLUSION: The incomplete healing may be attributed to the histological factors underlying the low healing rate and persistent MME. Notably, the region attached to the posterior-cruciate-ligament exhibited superior healing compared to other regions of the bony insertion in the repaired group. Conversely, the root-meniscus transition displayed discontinuity, representing a mechanical weakness in the healing process. CLINICAL RELEVANCE: Modifications of bone tunnel positioning and suture placement could be undertaken in subsequent studies to particularly enhance the healing of the root-meniscus transition.
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This study comprehensively compared the effects of laparoscopic and open radical cystectomies on postoperative wound infections and complications in patients with bladder cancer. We conducted a systematic search for relevant studies in PubMed, Embase, Google Scholar, Cochrane Library, China National Knowledge Infrastructure, and Wanfang databases, from database inception to October 2023. Two researchers independently screened the literature, extracted data, and assessed the quality based on the inclusion and exclusion criteria. Data analysis was performed using Stata 17.0 software. Overall, 16 studies involving 1427 patients with bladder cancer were included. The analysis revealed that, compared with open radical cystectomy, laparoscopic radical cystectomy significantly reduced the incidence of wound infections (odds ratio [OR] = 0.38, 95% confidence interval [CI]: 0.23-0.64, p < 0.001) and complications (OR = 0.35, 95%CI: 0.26-0.47, p < 0.001) and significantly shortened the hospital stay duration (standardised mean difference [SMD] = -1.85, 95%CI: -2.34 to -1.36, p < 0.001). Thus, this study determined that laparoscopic radical cystectomy for the treatment of bladder cancer effectively reduced the occurrence of wound infections and complications, and significantly shortened the patient's hospital stay, demonstrating notable therapeutic effectiveness worthy of clinical application.
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Cistectomia , Laparoscopia , Infecção da Ferida Cirúrgica , Neoplasias da Bexiga Urinária , Humanos , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/epidemiologia , Neoplasias da Bexiga Urinária/cirurgia , Laparoscopia/métodos , Laparoscopia/efeitos adversos , Cistectomia/efeitos adversos , Cistectomia/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Tempo de Internação/estatística & dados numéricos , Idoso de 80 Anos ou maisRESUMO
Chemical tagging via possible derivatization reagents alters metabolites' retention times, leading to different retention behavior during liquid chromatography-mass spectrometry (LC-MS) analysis. Incorporation of the retention time dimension can dramatically reduce false-positive structural elucidation in chemical-tagging-based metabolomics. However, few studies predict the retention times of chemically labeled metabolites, especially requiring a simple, easy-to-access, accurate, and universal predictor or descriptor. This pilot study demonstrates the application of volume-corrected free energy (VFE) calculation and region mapping as a new criterion to describe the retention time for structure elucidation in chemical-tagging-based metabolomics. The universality of VFE calculation is first evaluated with four different types of submetabolomes including hydroxyl-group-, carbonyl-group-, carboxylic-group-, and amino-group-containing compounds and oxylipins with similar chemical structures and complex isomers on reverse-phase LC. Results indicate a good correlation (r > 0.85) between VFE values and their corresponding retention times using different technicians, instruments, and chromatographic columns, describing retention behavior in reverse-phase LC. Finally, the VFE region mapping is described for identifying 1-pentadecanol from aged camellia seed oil using three proposed steps, including public database searching, VFE region mapping for its 12 isomers, and chemical standard matching. The possibility of VFE calculation of nonderivatized compounds in retention time prediction is also investigated, demonstrating its effectiveness on retention times with different influence factors.
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Metabolômica , Projetos Piloto , Metabolômica/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , IsomerismoRESUMO
Achieving long-term stable deep desulfurization at room temperature and recovering high value-added sulfone products is a challenge at present. Herein, a series of catalysts [Cnmim]5VW12O40Br (CnVW12, 1-alkyl-3-methylimidazolium bromide tungstovanadate, n = 4, 8, 16) were presented for the room temperature catalytic oxidation of dibenzothiophene (DBT) and its derivatives. Factors affecting the reaction process, such as the amount of catalyst, oxidant, and temperature, were systematically discussed. C16VW12 showed higher catalytic performance, and 100% conversion and selectivity could be achieved in 50 min with only 10 mg. The mechanism study showed that the hydroxyl radical was the active radical in the reaction. Benefiting from the "polarity strategy", the sulfone product accumulated after 23 cycles in a C16VW12 system, and the yield and purity were about 84% and 100%, respectively.
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BACKGROUND: Lymph node metastasis can independently predict oral squamous cell carcinoma patients' survival. This study would investigate the genetic and cellular differences between oral squamous cell carcinoma with positive and negative lymph node metastases. METHODS: We gathered single-cell RNA sequencing and bulk gene expression data from the Cancer Genome Atlas and Gene Expression Omnibus databases. Sixty lymph node-metastasis-related genes were discovered with refined single-cell RNA sequencing data analysis, and consensus clustering provided three molecular subtypes of oral squamous cell carcinoma. Least absolute shrinkage and selection operator analyses were then utilized to establish a five-gene risk model. CIBERSORT analysis revealed the immune infiltration profile of different risk subgroups. RESULTS: Oral squamous cell carcinoma patients were classified into three subtypes based on the 60 lymph node-metastasis-related key genes identified by single-cell RNA sequencing data. Patients in Subtype 3 showed a tendency for lymph node metastasis and poorer prognosis. Moreover, five biomarkers were selected from the 60 genes to construct a five-gene risk model evaluating the risk of lymph node metastasis. A lower probability of lymph node metastasis and a better prognosis was observed in the low-risk group. The immune infiltration of three different risk groups was explored with CIBERSORT. Besides, further analysis implied different sensitivities of anticancer drugs, including immunotherapy drugs and targeted compounds, in the three risk groups. CONCLUSION: In view of intratumoral heterogeneity, we found 60 genes associated with lymph node metastasis of oral squamous cell carcinoma. Subsequently, we constructed a five-gene signature that could improve the prediction of lymph node metastasis, clinical outcome, and promote individualized treatment strategies for oral squamous cell carcinoma.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Metástase Linfática/genética , Prognóstico , RNA-SeqRESUMO
Exploring the vegetation carbon cycle and the factors influencing vegetation carbon sequestration in areas with complex plateau-basin topography and fragile ecosystems is crucial. In this study, spatial and temporal characteristics of carbon sequestration by vegetation in Sichuan and Chongqing from 2010 to 2020 and the influencing factors were investigated through simulations of net primary productivity (NPP) using the modified Carnegie-Ames-Stanford approach (CASA) and the Thornthwaite Memorial (TM) model and using chemical equations of photochemical reactions. The results indicated that: The spatial distribution of carbon sequestration capacity (CSC) trends showed an increase in the east (the most prominent increased trend along the mountainous areas of the basin) and a decrease in the west (western Sichuan plateau). Differences exist in the impact factors of CSC in different regions. In the basin margins and mountainous areas, where the proportion of forests was high, a combination of climate change and human activities contributed to the increase in CSC. The relatively warm and humid meteorological conditions in the hinterland of the basin were more conducive to the increase in CSC, and climate change also affected the region more significantly. In contrast, in the relatively high altitude of western Sichuan, controlled human activities were the key to improving CSC. The results of the study contribute to the understanding of the basic theory of vegetation carbon cycle in areas with complex plateau-basin topography and fragile ecosystems, as well as to provide suggestions for ecological shelter construction and ecological restoration in the upper Yangtze River.
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Sequestro de Carbono , Ecossistema , Humanos , Mudança Climática , Florestas , Atividades Humanas , China , CarbonoRESUMO
The toxicity and environmental persistence of perfluorooctanoic acid (PFOA), and perfluorooctane sulfonate (PFOS) are of great concern for food intake in humans. However, PFASs conversion or conjugation to other substances in rice grown on PFASs polluted soil has not been explored clearly. These unknown transformed or conjugated products of PFOA and PFOS could be harmful to human health. The restriction factor in evaluating the possible transformation of PFOA and PFOS is mainly attributed to the lack of an efficient method for screening PFOA and PFOS and their related metabolites. To circumvent this challenge, we established a non-targeted screening method by combining a fluoro-cotton fiber-based solid phase extraction (FC-SPE) and liquid chromatography-high resolution mass spectrometry (LC-HRMS) to monitor the formation of possible organic fluorine compounds from rice (Oryza sativa L.) grown on PFASs. We synthesized fluoro-cotton fibers to serve as the FC-SPE packing material and characterized by field-emission scanning electron-microscope, Fourier transform infrared, and X-ray photoelectron spectroscopy measurements. The optimal extraction conditions for the prepared FC-SPE were investigated. The performance of FC-SPE in LC-MS analysis was validated by linearity, precision, recovery, and matrix effect. Then the FC-SPE combined with LC-HRMS was used to specifically capture organic fluorine compounds from complex matrices via F-F interaction, including rice seedlings grown in PFOA and PFOS polluted soil and soil samples. By the established FC-SPE LC-HRMS method, in total 429 features were found as the possible organic fluorine compounds from rice seedlings grown in PFOA polluted soil among the 1781 features from the rice seedlings. Finally, we employed a13C metabolic tracing analysis of organic fluorine compounds in combination with the FC-SPE LC-HRMS method to further identify the features that detected from rice seedlings grown in PFOA polluted soil. The final result indicated that there were not any new organic fluorine metabolites screened out from rice grown in PFOA or PFOS polluted soil.
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Ácidos Alcanossulfônicos , Compostos de Flúor , Fluorocarbonos , Oryza , Humanos , Fluorocarbonos/análise , Solo/química , Flúor , Ácidos Alcanossulfônicos/análise , CaprilatosRESUMO
The purpose of this study was to explore the effects of Rice straw and King grass on apparent digestibility, ruminal bacterial, and fungus composition in buffaloes. Three ruminal fistulated buffaloes were used in a 3 × 2 Latin square design. The dietary treatments were king grass and straw hay. Experimental animals were kept in individual pens and concentrate was offered at 1 kg/d while roughage was fed ad libitum. Each period lasted for 15d, with the first 12d for an adaptation period, followed by a 3-day formal trial period. King grass has higher digestibility of protein. Rice straw has higher digestibility to cellulose. The results showed that when buffaloes were fed king grass and straw, Bacteroidetes were dominant in the rumen normal flora, but firmicutes were not. In addition, the results of this experiment suggest that increasing protein content in diets may be beneficial to increase the relative abundance of Proteobacteria. Similarly, higher dietary fiber content may be beneficial for increasing relative abundance of Prevotella and Staphylococcus. The dominant fungi in ruminal fluid 2 h after ingestion were aerobic fungi. These aerobic fungi most likely entered the rumen with food. Whether and how long aerobic fungi can survive in the rumen needs more research.
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Oryza , Poaceae , Animais , Búfalos/metabolismo , Ração Animal/análise , Rúmen/metabolismo , DietaRESUMO
The first copper-catalyzed enantioselective [4 + 1] annulation of yne-allylic esters with 1,3-dicarbonyl compounds was realized through an elegant remote stereocontrol strategy. The very remote ε regioselective nucleophilic substitution was developed by employing a novel chiral copper-vinylvinylidene species from the new C4 synthon yne-allylic esters. Thus, greatly diverse spirocycles were obtained with ample scope and excellent levels of chemo-, regio-, and enantioselectivities. Moreover, detailed mechanistic studies suggest an yne-allylic substitution and Conia-ene cascade pathway on the remote stereochemical induction progress.
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Cobre , Ésteres , Cobre/química , Estereoisomerismo , Catálise , Estrutura MolecularRESUMO
Distinct regio- and enantioselectivity control in copper-catalyzed vinylogous and bisvinylogous propargylic substitution has been accomplished by using a novel chiral N,N,P ligand. The developed method provides an efficient and selective approach to an array of highly enantioenriched alkynyl unsaturated carbonyl compounds. Salient features include excellent functional group tolerance and broad substrate scope. The synthetic utility of the developed method is further demonstrated by a gram-scale synthesis and by application to a range of transformations including enantioselective synthesis of unique challenging compounds.
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Cobre , Catálise , Cobre/química , Ligantes , Estrutura Molecular , EstereoisomerismoRESUMO
RATIONALE: Assessing estrogen concentrations in biological systems can provide valuable information on physiological processes, which is crucial for the early diagnosis of many diseases. Because estrogens are present in the human body in low concentrations and in a wide dynamic range, analytical methods with high sensitivity and specificity are required for their determination in complex biological matrices. METHODS: To discover an appropriate derivatization reagent for estrogen mass spectrometry (MS) analysis, we compared five sulfonyl chloride derivatization reagents, namely 3-methyl-8-quinolinesulfonyl chloride (MQSCl) and 8-quinolinesulfonyl chloride (QSCl), 1-methyl-1H-pyrazole-4-sulfonyl chloride, 1,2-methyl-imidazole-5-sulfonyl chloride, and dansyl chloride. By selecting the derivatization reagent with the best performance, we developed and validated a novel chemical derivatization-assisted-liquid chromatography-electrospray ionization-tandem mass spectrometry (CD-LC-ESI-MS/MS) method to simultaneously determine the concentrations of estrone, estradiol, and estriol (E1, E2, and E3) in human serum. RESULTS: It was found that among the five investigated reagents, MQSCl-derivatized estrogens presented the highest sensitivity using LC-ESI-MS/MS. Based on this discovery, MQSCl was chosen to derivatize the analyzed estrogens to assist LC-ESI-MS/MS analysis. The limit of quantification of E1, E2, and E3 was measured as 2.7, 4.6, and 5.1 pg/mL, respectively. Inter- and intra-day precision, expressed as the coefficient of variation, was shown to be lower than 13.2% for all concentrations. The mean recovery was 72.4% overall, with good reproducibility at low, medium, and high concentrations in the calibration range. CONCLUSIONS: The developed method was successfully applied to the quantitative determination of estrogens in clinical human serum from pediatric and adult women, demonstrating the suitability of estrogen analysis in the biological matrix at low concentration (pg/mL).
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Estrogênios , Espectrometria de Massas em Tandem , Adulto , Criança , Cromatografia Líquida/métodos , Estrogênios/química , Feminino , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodosRESUMO
In recent years, dozens of halogenated disinfection byproducts (DBPs) with cyclic structures were identified and detected in drinking water globally. Previous in vivo toxicity studies have shown that a few new cyclic DBPs possessed higher developmental toxicity and growth inhibition rate than common aliphatic DBPs; however, in vitro toxicity studies have proved that the latter exhibited higher cytotoxicity and genotoxicity than the former. Thus, to provide a more comprehensive toxicity comparison of DBPs from different endpoints, 11 groups of cyclic DBPs and nine groups of aliphatic DBPs were evaluated for their comparative in vitro and in vivo toxicity using human hepatoma cells (Hep G2) and zebrafish embryos. Notably, results showed that the in vitro Hep G2 cytotoxicity index of the aliphatic DBPs was nearly eight times higher than that of the cyclic DBPs, whereas the in vivo zebrafish embryo developmental/acute toxicity indexes of the cyclic DBPs were roughly 48-50 times higher than those of the aliphatic DBPs, indicating that the toxicity rank order differed when different endpoints were applied. For a broader comparison, a Pearson correlation analysis of DBP toxicity data from nine different endpoints was conducted. It was found that the observed Hep G2 cytotoxicity and zebrafish embryo developmental/acute toxicity in this study were highly correlated with the previously reported in vitro CHO cytotoxicity and in vivo toxicity in aquatic organisms (P < 0.01), respectively. However, the observed in vitro toxicity had no correlation with the in vivo toxicity (P > 0.05), suggesting that the toxicity rank orders obtained from in vitro and in vivo bioassays had large discrepancies. According to the observed toxicity data in this study and the candidate descriptors, two quantitative structure-activity relationship (QSAR) models were established, which help to further interpret the toxicity mechanisms of DBPs from different endpoints.
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Desinfetantes , Água Potável , Poluentes Químicos da Água , Purificação da Água , Animais , Desinfetantes/toxicidade , Desinfecção , Água Potável/química , Halogenação , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Peixe-ZebraRESUMO
The low methanogenic efficiency of protein wastewater during anaerobic digestion can be attributed to the hydrolysis rate-limiting caused by the complex native structure of protein. In this study, the characterization of secondary structure alterations of protein molecules under acid-base stress was investigated and the effect of structure and conformation alterations on the methanogenic efficiency of protein wastewater biotransformation was analyzed. The optimal methane yields were obtained for protein wastewater pretreated with acid and base at pH = 3 and pH = 12, which was 29.4% and 35.7% higher than that of the control group (without pretreatment), reaching 142.6 ± 4.0 mL/g protein and 149.6 ± 16.1 mL/g protein, respectively. The time economy evaluation showed that 6 h pretreatment time was scientific and reasonable whether pH = 3 or pH = 12, since the methane gain effect reached 74.4% and 82.2% longing with the anaerobic digestion proceeded to 120 h, respectively. Endogenous fluorescence characteristics illustrated that the microenvironment of protein molecules has changed regardless of acid or alkali pretreatment. The circular dichroism (CD) analysis revealed that only the content of α-helix in the secondary structure of the protein at pH = 12 decreased by 46.3%, while the contents of ß-sheet, ß-turn and unordered structure were 29.5 ± 0.8%, 18.9 ± 0.6% and 32.2 ± 1.3%, respectively. The increase in the composition of the unordered structure demonstrated an irreversible damage to the hydrogen bonding network in the protein. FTIR spectroscopy further confirmed that the stretching vibrations of CO in amide I led to the destruction of the hydrogen bonding network and the unfolding of the protein structure. Thus, the above work provides new insights into the anaerobic digestion of protein wastewater for methanogenic processes from the perspective of protein structure and conformational changes.
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Eliminação de Resíduos Líquidos , Águas Residuárias , Anaerobiose , Reatores Biológicos , Biotransformação , Ligação de Hidrogênio , Metano , Esgotos/química , Eliminação de Resíduos Líquidos/métodosRESUMO
This study developed a method to build relationships between chemical fractionations of heavy metals in soils and their accumulations in rice and estimate the respective contribution of each geochemical speciation in the soils from the Yangtze River Delta, China. In contaminated areas, residue and humic acid-bound fractions in soils were the main phases for most heavy metals. The mobility of heavy metals was in this following order: Cd > Pb ≈ Zn > Ni > As ≈ Cr > Hg. Transfer factors calculated by the ratios of specific fractionations of heavy metals in the soil-rice system were used to assess the capability of different metal speciation transfer from soil to rice. The carbonate and Fe/Mn oxyhydroxides bound phase had significant positive correlations with total metal concentrations in rice. Hg uptake by rice might be related to the exchangeable and carbonate-bound fractions of soil Hg. Results of PCA analysis of transfer factors estimated that the labile fractions (i.e. water soluble, exchangeable and carbonate bound) contributed more than 40% of the heavy metal accumulations in rice. Effect of organic matter and residue fraction on metals transfer was estimated to be ~ 25 to ~ 30% while contribution of humic acid and Fe/Mn oxyhydroxides-bound fractions was estimated to be ~ 20 to ~ 30%. Modified risk assessment code (mRAC) and ecological contamination index (ECI) confirmed that the soil samples were polluted by heavy metals. Soil Cd contributed more than 80% of mRAC. Contrarily, the main contributors to ECI were identified as As, Hg, Pb and Zn. The average values of total target hazard quotient (TTHQ) and Risktotal were above 1 and 10-4 respectively, implying people living in the study area were exposed to both non-carcinogenic and carcinogenic risk. As and Pb were the main contributor to high TTHQ value while As, Cd and Cr in rice contributed mostly to Risktotal value. Spatial changes of ecological risk indexes and human health risk indexes showed that the samples with high TTHQ values distributed in the area with high values of mRAC. Likewise, the area with high ECI values and with high carcinogenic risk overlapped.
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Metais Pesados , Oryza , Poluentes do Solo , Disponibilidade Biológica , Fracionamento Químico , China , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Medição de Risco , Solo/química , Poluentes do Solo/análiseRESUMO
An editorial decision has been made to retract this manuscript due to breach of publishing guidelines, following the identification of non-original and manipulated figures. Reference: Hua-ming Chi, Jing-dong Du, Jie Cheng, Hua-dong Mao: Taxol-Resistant Gene 1 (Txr1) Mediates Oxaliplatin Resistance by Inducing Autophagy in Human Nasopharyngeal Carcinoma Cells. Med Sci Monit 2019; 25:475-483. 10.12659/MSM.913180.
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PURPOSE: This study aimed to analyze a Chinese institution's experience with managing cervical necrotizing fasciitis (CNF) and observe the effects of a new therapeutic approach for postoperative drainage system. METHODS: A retrospective study was established including a total of 46 CNF patients who underwent surgical debridement between April 2006 and April 2018. Analyses of demographic data, etiology, comorbidity, microbiology, complications, treatment methods, duration of treatment, and treatment outcomes were obtained. RESULTS: There were 16 kinds of microbes cultured in 29 patients. Diabetic patients were more commonly infected by microbes (P < 0.05). There was a significant reduction in the number of operative time (P < 0.05) and length of hospitalization (P < 0.01) with postoperative therapy of double-cannula irrigation-drainage (DCID) system. CONCLUSION: CNF management includes controlling for comorbidities especially glycemic control and reasonable utilization of antibiotics and aggressive postoperative therapy. DCID system can effectively reduce operative frequency and duration of hospitalization.
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Fasciite Necrosante , Cânula , China/epidemiologia , Desbridamento , Drenagem , Fasciite Necrosante/epidemiologia , Fasciite Necrosante/cirurgia , Humanos , Pescoço/cirurgia , Estudos RetrospectivosRESUMO
Identification of metabolites at the trace level in complex samples is still one of the major challenges in untargeted metabolomics. One formula in the metabolomic database is always corresponding to more than one candidate, which increases the difficulty and cost in the subsequent process of standard compound matching. In this study, we developed an effective method for amine metabolite identification by hydrogen-deuterium scrambling (HDS) based on chemical isotope labeling coupled with liquid chromatography-mass spectrometry (HDS-CIL-LC-MS). After d4-4-(N,N-dimethylamino)phenyl isothiocyanate (d4-DMAP) labeling, the labeled amine metabolites can produce HDS under collision-induced dissociation (CID). The HDS can effectively reflect the number of labile hydrogen atoms in amine metabolites and thus distinguish amine isomers with different functional groups. The developed HDS-CIL-LC-MS method was applied to the determination of amine metabolites in mice feces, in which the amine candidates obtained by the database based on chemical formula searching were reduced by 64% on average, which greatly reduces the cost of standard compound matching. Taken together, the developed HDS-CIL-LC-MS analysis was demonstrated to be a promising method for untargeted metabolomics and a novel strategy for deciphering tandem mass spectrometry (MS2) spectra.
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Aminas/análise , Aminas/metabolismo , Medição da Troca de Deutério , Metabolômica , Animais , Cromatografia Líquida , Fezes/química , Camundongos , Estrutura Molecular , Espectrometria de Massas em TandemRESUMO
The development of catalysts for oxidation of aqueous contaminants has long been relying on trial-and-error strategies due to lack of activity-tuning principles. Herein, Fenton-like oxidation of As(III) as a chemisorbed model contaminant over a series of fabricated CexTi1-xO2 catalysts with tunable structures was investigated. The activity of CexTi1-xO2 showed a volcano-shape dependency on Ce molar fraction, peaking at Ce0.25Ti0.75O2 (x = 0.25) with 6.32-6.36 times higher activity and 2.67-2.94 times higher specific activity compared with CeO2 and TiO2. The non-radical surface hydroperoxo complexes were experimentally substantiated as the dominant oxidant species on Ce0.25Ti0.75O2, which enabled a high efficiency of H2O2 utilization (99.1%). Under the verified Langmuir-Hinshelwood mechanism, the microkinetic model for the catalytic oxidation was established, and thus, the quantitative relationship between activity and adsorption energies for bimolecular chemisorption reactions was elucidated. Theoretically, a catalyst with identical adsorption energies toward both chemisorbed reactants tends to obtain the highest activity. Through DFT calculation, the highest activity of Ce0.25Ti0.75O2 was rationally interpreted by the balanced adsorption energies toward As(III) and H2O2, which was attributed to the shifted electronic density of states induced by Ce doping. This study provides a potent strategy to tune the catalytic activity of bimolecular chemisorption reactions.