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Nucleic acid modifications have attracted increasing attention in recent years since they have been found to be related to a number of diseases including cancer. Previous studies have shown that the early development of endometrial cancer (EC) is often accompanied by changes in methylation levels of related genes, and the expression of related proteins that regulate reactive oxygen species (ROS) shows significant differences in EC cells and tissues. However, it has not been reported whether nucleic acid modifications related to methylation or ROS can serve as biomarkers for EC. Accurate quantification of these nucleic acid modifications still has challenges because their amounts in urine are very low and the interferences in urine are complicated. In this study, a novel dispersive solid-phase extraction (DSPE) method based on chitosan-carbon nanotube-Al2O3 (CS-CNT-Al2O3) has been established for the analysis of 5-hydroxymethyluracil (5 mU), 5-methyl-2'-deoxycytidine (5-mdC), 5-hydroxymethyl-2'-deoxycytidine (5-hmdC), 5-formyl-2'-deoxycytidine (5-fdC), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in EC patient urine samples coupled with UHPLC-QE-Orbitrap-MS/MS and HPLC-UV. Firstly, the synthesis of the CS-CNT-Al2O3 nanocomposite was conducted by a sono-coprecipitation method and was characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), and Fourier transform infrared (FTIR). Under the optimal extraction conditions of DSPE, we successfully quantified 5 mU, 5-mdC, 5-hmdC, 5-fdC, and 8-OHdG in urine samples from 37 EC patients and 39 healthy controls. The results showed that there were significant differences in the levels of 5-mdC, 5-hmdC, 5-fdC, and 8-OHdG in EC patients compared to the healthy control group. The receiver operator characteristic (ROC) curve analysis was carried out to evaluate the potential of 5-mdC, 5-hmdC, 5-fdC, and 8-OHdG to distinguish EC patients from healthy volunteers. The area under the curve (AUC) for 5-mdC, 5-hmdC, 5-fdC, and 8-OHdG was 0.7412, 0.667, 0.8438, and 0.7981, respectively. It indicated that 5-mdC, 5-hmdC, 5-fdC, and 8-OHdG had certain potential in distinguishing between EC patients and healthy volunteers and they could act as potential non-invasive biomarkers for early diagnosis of EC. Moreover, the present study would stimulate investigations of the effects of nucleic acid modifications on the initiation and progression of EC.
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Neoplasias do Endométrio , Ácidos Nucleicos , Humanos , Feminino , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Espécies Reativas de Oxigênio , 8-Hidroxi-2'-Desoxiguanosina , Neoplasias do Endométrio/diagnóstico , Extração em Fase Sólida , BiomarcadoresRESUMO
Zn-Mn batteries with two-electron conversion reactions simultaneously on the cathode and anode harvest a high voltage plateau and high energy density. However, the zinc anode faces dendrite growth and parasitic side reactions while the Mn2+/MnO2 reaction on the cathode involves oxygen evolution and possesses poor reversibility. Herein, a novel nanomicellar electrolyte using methylurea (Mu) has been developed that can encapsulate ions in the nanodomain structure to guide the homogeneous deposition of Zn2+/Mn2+ in the form of controlled release under an external electric field. Consecutive hydrogen bonding network is broken and a favorable local hydrogen bonding system is established, thus inhibiting the water-splitting-derived side reactions. Concomitantly, the solid-electrolyte interface protective layer is in situ generated on the Zn anode, further circumventing the corrosion issue resulting from the penetration of water molecules. The reversibility of the Mn2+/MnO2 conversion reaction is also significantly enhanced by regulating interfacial wettability and improving nucleation kinetics. Accordingly, the modified electrolyte endows the symmetric Znâ¥Zn cell with extended cyclic stability of 800 h with suppressed dendrites growth at an areal capacity of 1 mAh cm-2. The assembled Zn-Mn electrolytic battery also demonstrates an exceptional capacity retention of nearly 100% after 800 cycles and a superior energy density of 800 Wh kg-1 at an areal capacity of 0.5 mAh cm-2.
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Supported bimetallic nanoparticle catalysts with small size have attracted wide research attention in catalysis but are difficult to synthesize because high-temperature annealing required for alloying inevitably accelerates metal sintering and leads to larger particles. Here, we report a simple and scalable "critical interparticle distance" method for the synthesis of a family of bimetallic nanocluster catalysts with an average particle size of only 1.5 nm by using large-surface-area carbon black supports at high temperatures, which consist of 12 diverse combinations of 3 noble metals (Pt, Ru, and Rh) and 4 other metals (Cr, Fe, Zr, and Sn). In this strategy, high-temperature treatments ensure the formation of alloyed bimetallic nanoparticles and enlargement of the interparticle distance on high-surface-area supports significantly suppresses metal sintering. The prepared ultrafine Pt2Sn and RuSn nanocluster catalysts exhibited enhanced performance in catalyzing the synthesis of aromatic secondary amines and the selective hydrogenation of furfural, respectively.
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Size control of supported Pd-based intermetallic nanoparticles (i-NPs) remains a major challenge because the required high-temperature annealing for atomic diffusion and ordering easily causes metal sintering. Here, we described a pentacoordinate Al3+ site (Al3+penta) anchoring approach for the preparation of Pd-based i-NPs with controlled size, which takes advantage of the strong chemical interaction between Al3+penta sites and Pd-based i-NPs to realize size control. We synthesized six types of Pd-based i-NPs, and four of them can remain an average particle size of <6 nm. Furthermore, one of our prepared Pd-based i-NPs (that is, Pd3Pb) demonstrated outstanding performance in catalyzing the semihydrogenation of phenylacetylene.
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BACKGROUND: Bacterial infection of adenoid is currently considered to be an important cause of adenoid hypertrophy (AH) in children. Although several bacteriology studies on adenoid diseases have been reported, the aerobic bacterial study regarding risk factors and antibiotic sensitivity of AH in Chinese children is lacking. This study aims to investigate the risk factors for aerobic bacterial colonization of AH in Chinese children and to elucidate aerobic bacterial profiles and antibiotic sensitivity. METHODS: Samples were collected from the adenoid core and surface tissue of 466 children undergoing adenoidectomy. Aerobic cultures and antibiotic sensitivity were observed. The risk factors for bacterial colonization of adenoid were analyzed statistically. RESULTS: A total of 143 children could be detected opportunistic pathogens in adenoid surface and/or core tissue, with a carriage rate of 30.7%. The presence of chronic rhinosinusitis, tonsillar hypertrophy and adenoidal size were the risk factors for aerobic bacterial colonization of adenoid in univariate analysis. Multivariate analysis showed that chronic rhinosinusitis and tonsil hypertrophy were significant variables associated with the aerobic bacterial colonization. The most frequently isolated aerobic bacteria were Haemophilus influenzae, followed by Staphylococcus aureus and Streptococcus pneumoniae. There was no statistically significant difference in bacterial species between the adenoid surface and core. The above common bacteria were more sensitive to cephalosporins and quinolones antibiotics, and significantly resistant to penicillin antibiotics and non-ß-lactamase inhibitors. CONCLUSION: Our results provide recent aerobic bacterial profiles for AH among Chinese children and confirm the risk factors and antibiotic sensitivity. This study contributes to understanding the role of different risk factors in the development of AH and will be helpful to the treatment of AH among Chinese children.
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Tonsila Faríngea , Quinolonas , Infecções Estafilocócicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias Aeróbias , Cefalosporinas , Criança , China , Humanos , Hipertrofia , Penicilinas , Fatores de RiscoRESUMO
Catalytic biomass conversions are sustainable processes to produce value-added fuels and chemicals but need stable catalysts that can tolerate harsh hydrothermal conditions. Herein, we report a hydrothermally stable catalyst by alloying Pt with a high-melting-point metal Nb. The Pt/Nb alloy catalysts are prepared by H2 reduction at a high temperature of 900 °C with a high-surface-area carbon black support, which can suppress metal sintering at high temperatures and thus lead to small-sized alloyed Pt/Nb particles of only 2.2 nm. Taking the advantages of surface acid property provided by the Nb sites and the size effect, the prepared C-supported small-sized Pt/Nb alloy catalysts exhibit attractive activities for the hydrogenation of levulinic acid into γ-valerolactone and the water-gas shift reaction. More significantly, benefiting from the inherent stability of high-melting-point Nb, the Pt/Nb alloy catalysts show much enhanced hydrothermal stability compared to commercial Pt/C and Ru/C catalysts.
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Here, we report a "critical distance" method for the synthesis of 9 kinds of sub-5 nm rhodium (Rh)-based intermetallic catalysts. Enlarging the distance between intermetallic particles on high-surface-area carbon black supports could significantly suppress the metal sintering in high-temperature annealing. The prepared Rh2Sn intermetallic catalysts exhibited enhanced activity in catalyzing the hydrogenation of nitrobenzene.
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Introduction: Alzheimer's disease (AD) is the most common type of dementia, impacting approximately 50 million individuals globally. However, the current treatments available for AD are only symptomatic and have limited efficacy. This study aimed to investigate whether Leonurine could alleviate cognitive dysfunction in a mouse model of AD and explore its underlying molecular mechanisms. Methods: In this study, male APP/PS1 mice were orally administered Leonurine for two consecutive months. The cognitive functions of the mice were then evaluated using novel object recognition (NOR) and Morris water maze (MWM) tests. Hippocampal neuronal damage was observed through Nissl staining, Aß levels were determined through ELISA, oxidative stress activity was detected through biochemical methods, and the nuclear factor erythroid-2-related factor 2 (Nrf-2) pathway was analyzed using western blot and real-time quantitative polymerase chain reaction analysis. Results: Our results demonstrated that Leonurine treatment markedly improved cognitive functions, as indicated by the improved performance in the model. Additionally, histopathology showed a reduction in hippocampal neuronal damage. This can be attributed to the potential of Leonurine to reduce Aß1-40 and Aß1-42 levels and alleviate oxidative stress. Its antioxidant effect is linked to the activation of the Nrf-2 signaling pathway in APP/PS1 mice, which promotes Nrf-2 nuclear translocation and expression of HO-1 and NQO-1. Conclusion: These findings suggest that Leonurine could be explored further as it could emerge as a promising drug for AD treatment.
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Supported ordered intermetallic compounds exhibit superior catalytic performance over their disordered alloy counterparts in diverse reactions. But the synthesis of intermetallic compounds catalysts often requires high-temperature annealing that leads to the sintering of metals into larger crystallites. Herein, we report a small molecule-assisted impregnation approach to realize the general synthesis of a family of intermetallic catalysts, consisting of 18 binary platinum intermetallic compounds supported on carbon blacks. The molecular additives containing heteroatoms (that is, O, N, or S) can be coordinated with platinum in impregnation and thermally converted into heteroatom-doped graphene layers in high-temperature annealing, which significantly suppress alloy sintering and insure the formation of small-sized intermetallic catalysts. The prepared optimal PtCo intermetallics as cathodic oxygen-reduction catalysts exhibit a high mass activity of 1.08 A mgPt-1 at 0.9 V in H2-O2 fuel cells and a rated power density of 1.17 W cm-2 in H2-air fuel cells.
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To investigate the short- and long-term impacts of adenoidectomy with/without tonsillectomy on the immune functions of young children < 3 years of age.This longitudinal prospective study included 40 pediatric patients (age <3 y) undergoing adenoidectomy with/without tonsillectomy for snoring and sleep apnea. Serum immunoglobulin IgA, IgG, IgM, complement C3, and C4 levels were measured for the status of humoral immunity; CD3+, CD4+, CD8+, CD4+/CD8+, CD19+, CD56+, CD3+CD4-CD8-, and CD3+CD4+CD8+ T cells were measured for the status of cellular immunity. Blood samples were taken at 3 time points: before surgery, 1 month after surgery (short-term), and 3 months after surgery (long-term). All patients were assessed for short-term outcome at 1-month postoperation, but only 30 patients were followed at 3 months after surgery. The incidence of recurrent respiratory tract infections and other immune-related conditions were recorded at each follow-up.The levels of IgA significantly decreased from the preoperative level at 1-month follow-up (Pâ<â.05), but still within normal range. No significant changes were found in the levels of IgA, IgG, IgM, C3, C4, CD3+, CD4+, CD8+, CD4+/CD8+, CD19+, CD56+, CD3+CD4-CD8-, and CD3+CD4+CD8+ T cell at 3-month follow-up in comparison with preoperative levels. There was also no episode of recurrent respiratory tract infection and other immune-deficiency conditions.Adenoidectomy with/without tonsillectomy may result in a reduction in individual antibodies in children <3 years of age, but did not show negative impacts on their immune functions. Also, the surgery does not lead to the increased risk of upper respiratory tract infection in these children.
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Adenoidectomia/efeitos adversos , Imunidade Celular , Imunidade Humoral , Tonsilectomia/efeitos adversos , Pré-Escolar , Feminino , Humanos , Lactente , Estudos Longitudinais , Masculino , Estudos ProspectivosRESUMO
Objective: To evaluate the early stage effects of adenoidectomy with/without tonsillectomy on immune functions in children aged <3 years. Methods: Twenty-four children aged <3 years underwent adenoidectomy with/without tonsillectomy were included. The levels of IgG, IgA, IgM, C3, and C4 were measured for humoral immunity, and the levels of CD3+, CD4+, CD8+, CD19+, CD56+, CD3+CD4-CD8-, and CD3+CD4+CD8+ T cells were measured for cellular immunity before and 2 weeks after the operation. Results: The postoperative levels of IgA, IgG, IgM, C3, and C4 were significantly increased compared with the preoperative levels (P < 0.05). The levels of CD3+, CD4+, CD8+, CD56+, CD3+CD4-CD8-, and CD3+CD4+CD8+ T cells were increased, while the level of CD19+ was decreased in postoperative period compared with preoperative period. Compared with those in the control group, the preoperative levels of IgA, IgG, and CD3+CD4+CD8+ T cells were significantly increased (P < 0.05), while the levels of IgM, C3, C4 and CD3+, CD4+, CD8+, CD56+, and CD3+CD4-CD8- T cells were not significantly changed. The postoperative levels of IgA, IgG, C3, C4, CD3+CD4-CD8-, and CD3+CD4+CD8+ T cells were significantly increased (P < 0.05), while the levels of IgM, CD3+, CD4+, CD8+, and CD56+ T cells were not significantly changed compared with those in the control group. Conclusion: Adenoidectomy with/without tonsillectomy could stimulate the immune responses, which could avoid significant immune deficiency in a short period of time in children aged <3 years.
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Corpos Estranhos , Enfisema Subcutâneo , Brônquios , Broncoscopia , Criança , Humanos , Enfisema Subcutâneo/etiologiaRESUMO
OBJECTIVE: To analyze the distribution and drug susceptibility of the pathogenic bacteria in the airway secretions in children with tracheobronchial foreign bodies so as to assist physicians in clinical prescription. METHODS: Sputum specimens of 1 125 children with tracheobronchial foreign bodies were collected in removal of the foreign bodies by rigid bronchoscope, and the drug susceptibility test was performed. RESULTS: Pathogenic bacteria were detected in 218 (19.4%) of 1 125 sputum specimens. Among the pathogenic bacteria, 126 (57.79%) strains were gram-negative bacilli, consisting of 76 (34.86%) strains of Haemophilus influenzae, 10 (4.59%) strains of Escherichia coli, 7 (3.21%) strains of Sewer enterobacter, 7 (3.21%) strains of Pseudomonas aeruginosa, and 6 (2.75%) strains of Klebsiella bacillus; and 92 (42.21%) strains were gram-positive bacilli, consisting of 80 (36.69%) strains of Streptococcus pneumonia and 10 (4.59%) strains of Escherichia coli. Most of detected gram-negative bacilli were highly sensitive to cefepime, ceftazidine, imipenem and amikacin, no strains were resistant to meropenem and ciprofloxacin. None of the detected gram-positive bacilli were resistant to cefepime, vancomycin, levofloxacin and teicoplanin. CONCLUSIONS: The Haemophilus influenzae of gram-negative bacilli and the Streptococcus pneumonia of gram-positive bacilli are the main pathogenic bacteria existing in the airway secretions of children with tracheobronchial foreign bodies. The Haemophilus influenzae were highly sensitive to cephalosporin, imipenem and amikacin, and the Streptococcus pneumonia to cefepime, vancomycin, levofloxacin and teicoplanin.
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Bactérias/crescimento & desenvolvimento , Farmacorresistência Bacteriana/genética , Corpos Estranhos/epidemiologia , Escarro/microbiologia , Bactérias/classificação , Bactérias/genética , Cefepima , Cefalosporinas , Criança , Bactérias Gram-Negativas , Humanos , Meropeném , Testes de Sensibilidade Microbiana , TienamicinasRESUMO
BACKGROUND: Thirty thousand infants are born every year with congenital hearing impairment in mainland China. Racial and regional factors are important in clinical diagnosis of genetic deafness. However, molecular etiology of hearing impairment in the Tibetan Chinese population living in the Tibetan Plateau has not been investigated. To provide appropriate genetic testing and counseling to Tibetan families, we investigated molecular etiology of nonsyndromic deafness in this population. METHODS: A total of 114 unrelated deaf Tibetan children from the Tibet Autonomous Region were enrolled. Five prominent deafness-related genes, GJB2, SLC26A4, GJB6, POU3F4, and mtDNA 12S rRNA, were analyzed. Inner ear development was evaluated by temporal CT. A total of 106 Tibetan hearing normal individuals were included as genetic controls. For radiological comparison, 120 patients, mainly of Han ethnicity, with sensorineural hearing loss were analyzed by temporal CT. RESULTS: None of the Tibetan patients carried diallelic GJB2 or SLC26A4 mutations. Two patients with a history of aminoglycoside usage carried homogeneous mtDNA 12S rRNA A1555G mutation. Two controls were homozygous for 12S rRNA A1555G. There were no mutations in GJB6 or POU3F4. A diagnosis of inner ear malformation was made in 20.18% of the Tibetan patients and 21.67% of the Han deaf group. Enlarged vestibular aqueduct, the most common inner ear deformity, was not found in theTibetan patients, but was seen in 18.33% of the Han patients. Common molecular etiologies, GJB2 and SLC26A4 mutations, were rare in the Tibetan Chinese deaf population. CONCLUSION: The mutation spectrum of hearing loss differs significantly between Chinese Tibetan patients and Han patients. The incidence of inner ear malformation in Tibetans is almost as high as that in Han deaf patients, but the types of malformation vary greatly. Hypoxia and special environment in plateau may be one cause of developmental inner ear deformity in this population.