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Multiview clustering has become a prominent research topic in data analysis, with wide-ranging applications across various fields. However, the existing late fusion multiview clustering (LFMVC) methods still exhibit some limitations, including variable importance and contributions and a heightened sensitivity to noise and outliers during the alignment process. To tackle these challenges, we propose a novel regularized instance weighting multiview clustering via late fusion alignment (R-IWLF-MVC), which considers the instance importance from various views, enabling information integration to be more effective. Specifically, we assign each sample an importance attribute to enable the learning process to focus more on the key sample nodes and avoid being influenced by noise or outliers, while laying the groundwork for the fusion of different views. In addition, we continue to employ late fusion alignment to integrate base clustering from various views and introduce a new regularization term with prior knowledge to ensure that the learning process does not deviate too much from the expected results. After that, we design a three-step alternating optimization strategy with proven convergence for the resultant problem. Our proposed approach has been extensively evaluated on multiple real-world datasets, demonstrating its superiority to state-of-the-art methods.
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Background: The COVID-19 pandemic underscored the critical importance of biosafety in microbiology laboratories worldwide. In response, China has ramped up its efforts to enhance biosafety measures within its Centers for Disease Control and Prevention (CDC) laboratories. This study provides the first comprehensive assessment of biosafety practices across provincial, city, and county levels of CDC microbiology laboratories in China. Methods: We conducted a nationwide cross-sectional survey from 2021 to 2023, targeting staff from microbiology laboratories within CDCs at all administrative levels in China. Stratified sampling was employed to select respondents, ensuring a representative mix across different CDC hierarchies, job titles, and academic qualifications. The survey encompassed questions on biosafety training, the presence of BSL-2 and BSL-3 laboratories, adherence to general biosafety guidelines, and management practices regarding specimens, reagents, and consumables. Statistical analysis was performed to identify significant differences in biosafety practices among different CDC levels. Results: A total of 990 valid responses were received, highlighting a nearly universal presence (98.69%) of BSL-2 laboratories and a significant yet varied presence of BSL-3 laboratories across the CDC network. The survey revealed high levels of biosafety training (98.69%) and adherence to biosafety protocols. However, challenges remain in the consistent application of certain safety practices, especially at lower administrative levels. Notable differences in the management of specimens, reagents, and consumables point to areas for improvement in ensuring biosecurity. Conclusion: Our findings indicate a robust foundation of biosafety practices within CDC microbiology laboratories in China, reflecting significant advancements in the wake of the Biosecurity Law's implementation. Nevertheless, the variability in adherence to specific protocols underscores the need for ongoing training, resources allocation, and policy refinement to enhance biosafety standards uniformly across all levels. This study's insights are crucial for guiding future improvements in laboratory biosafety, not just in China but potentially in other countries enhancing their public health infrastructures.
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Contenção de Riscos Biológicos , Laboratórios , China , Humanos , Estudos Transversais , Laboratórios/normas , Contenção de Riscos Biológicos/normas , Inquéritos e Questionários , COVID-19/prevenção & controleRESUMO
OBJECTIVE: This study aimed to establish a highly sensitive and rapid single-tube, two-stage, multiplex recombinase-aided qPCR (mRAP) assay to specifically detect the khe, blaKPC-2, and blaNDM-1 genes in Klebsiella pneumoniae. METHODS: mRAP was carried out in a qPCR instrument within 1 h. The analytical sensitivities of mRAP for khe, blaKPC-2, and blaNDM-1 genes were tested using recombinant plasmids and dilutions of reference strains. A total of 137 clinical isolates and 86 sputum samples were used to validate the clinical performance of mRAP. RESULTS: mRAP achieved the sensitivities of 10, 8, and 14 copies/reaction for khe, blaKPC-2, and blaNDM-1 genes, respectively, superior to qPCR. The Kappa value of qPCR and mRAP for detecting khe, blaKPC-2, and blaNDM-1 genes was 1, 0.855, and 1, respectively (p < 0.05). CONCLUSION: mRAP is a rapid and highly sensitive assay for potential clinical identification of khe, blaKPC-2, and blaNDM-1 genes in K. pneumoniae.
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Klebsiella pneumoniae , Reação em Cadeia da Polimerase Multiplex , beta-Lactamases , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , beta-Lactamases/genética , Humanos , Reação em Cadeia da Polimerase Multiplex/métodos , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/diagnóstico , Sensibilidade e Especificidade , Reação em Cadeia da Polimerase em Tempo Real/métodos , Proteínas de Bactérias/genética , Recombinases/genética , Recombinases/metabolismoRESUMO
The simple preparation of mesoporous NiS2//MoS2 composite catalyst through a one-pot solvothermal method is presented. The improvement of the specific surface area (220 m2/g) and the construction of the porous structure are realized by this method in the case of no support. The organics acts as a microscopic binder contribute to uniform stacking of MoS2 with NiS2 clusters. The composite structure including NiS2 and MoS2 was obtained (proved by XRD, XPS, TEM, IR, UV-vis and RAMAN) and changed the microelectronic environment of the active metal surface (DFT calculation). The mesoporous NiS2//MoS2 catalyst (Ni1Mo1-200) showed an excellent hydrodesulfurization performance of dibenzothiophene (DBT conversion: 78 % at 260 °C) and a high ratio of direct desulfurization pathway (SDDS/HYD = 16.6) at a low reaction temperature. By combining the characterization and theoretical calculation results, the advantages of this NiS2//MoS2 composite structure in synergistic catalysis was further confirmed.
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Monitoring the spatiotemporal dynamics of cancer biomarkers within the tumor microenvironment (TME) is critical to understanding their roles in tumorigenesis. Here, we reported a multifunctional fusion protein (collagen-binding domain and duck circovirus tag fused to mCherry, CBD-mCherry-DCV) capable of binding collagen with high affinity and covalently binding specific nucleic acids with exceptional efficiency. We then constructed a chimeric protein-nucleic acid nanodevice (CPNN) using CBD-mCherry-DCV and an aptamer-based sensing module to enable spatially controlled ratiometric imaging of cancer biomarkers in the TME. The collagen-anchoring module CBD-mCherry-DCV allowed specific immobilization of CPNN on 3D multicellular tumor spheroids, enabling the sensing module to achieve "off-on" fluorescence imaging of cancer biomarkers upon specific target recognition by an aptamer. Taking advantage of the constant fluorescence signal of mCherry and the activatable fluorescence response of Cy5 to specific cancer biomarkers, the detection sensitivity and reliability of CPNN were improved by self-calibrating the signal intensity. Specifically, CPNN enabled ratiometric fluorescence imaging of varying concentrations of exogenous PDGF-BB and ATP in tumor spheroids with a high signal-to-background ratio. Furthermore, it allowed the visual monitoring of endogenous PDGF-BB and ATP released from cells. Overall, this study demonstrates the potential of the nanodevice as a versatile approach for the visualization and imaging of cancer biomarkers in the TME.
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The rapid recombination of photogenerated carriers of photocatalysts greatly limits their actual application in CO2 conversion into valuable chemicals. Herein, dual CuOx and MnOx cocatalysts are decorated on g-C3N4 nanosheets via a one-step photodeposition strategy. Benefiting from the repulsion between Cu2+ and Mn2+ cations, a novel g-C3N4-based heterostructure loaded with spatially separated CuOx and MnOx nanoparticle dual cocatalysts has been successfully fabricated. Cu favors the trapping of electrons, while MnOx tends to collect holes. Moreover, the Cu2O/g-C3N4 p-n heterojunction also accelerates the charge separation. As a result, the photogenerated holes and electrons flow into and out of the photocatalyst, respectively, resulting in enhanced charge separation for achieving efficient CO2 photoreduction over CuOx/g-C3N4/MnOx. Accordingly, the optimized CuOx/g-C3N4/MnOx exhibits an improved CO production rate of 5.49 µmol g-1 h-1, which is 27.5 times higher than that of bare g-C3N4.
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Encephalitis and meningitis are notable global public health concerns, especially among infants or children. Metagenomic next-generation sequencing (mNGS) has greatly advanced our understanding of the viruses responsible for these diseases. However, the detection rate of the aetiology remains low. We conducted RNA sequencing and virome analysis on cerebrospinal fluid (CSF) and serum samples commonly used in the clinical diagnosis to detect viral pathogens. In total, 226 paired CSF and serum samples from 113 children with encephalitis and meningitis were enrolled. The results showed that the diversity of viruses was higher in CSF, with a total of 12 viral taxa detected, including one case each of herpesvirus, coronavirus and enterovirus, and six cases of adenovirus related to human diseases. In contrast, the Anelloviridae was the most abundant viral family detected in serum, and only a few samples contained human viral pathogens, including one case of enterovirus and two cases of adenovirus. The detection rate for human viral pathogens increases to 10.6â%(12/113) when both types of samples are used simultaneously, compared to CSF along 7.9â% (9/113) or serum alone 2.6â% (3/113). However, we did not detect these viruses simultaneously in paired samples from the same case. These results suggest that CSF samples still have irreplaceable advantages for using mNGS to detect viruses in patients with meningitis and encephalitis, and serum can supplement to improve the detection rate of viral encephalitis and meningitis. The findings of this study could help improve the etiological diagnosis, clinical management and prognosis of patients with meningitis and encephalitis in children.
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Encefalite , Enterovirus , Meningite , Vírus , Lactente , Humanos , Criança , Encefalite/líquido cefalorraquidiano , Encefalite/diagnóstico , Vírus/genética , Enterovirus/genética , Análise de Sequência de RNA , RNARESUMO
Objective: The worldwide incidence of primary small intestinal lymphoma (PSIL) is increasing. However, little is known about the clinical and endoscopic characteristics of this disease. The aim of this study was to investigate the clinical and endoscopic data of patients with PSIL, with the goal of enhancing our understanding of the disease, improving diagnostic accuracy, and facilitating more accurate prognosis estimation. Methods: Ninety-four patients diagnosed with PSIL were retrospectively studied at Qilu Hospital of Shandong University between 2012 and 2021. The clinical data, enteroscopy findings, treatment modalities, and survival times were collected and analyzed. Results: Ninety-four patients (52 males) with PSIL were included in this study. The median age of onset was 58.5 years (range: 19-80 years). Diffuse large B-cell lymphoma (n=37) was the most common pathological type. Abdominal pain (n=59) was the most frequent clinical presentation. The ileocecal region (n=32) was the most commonly affected site, and 11.7% of patients had multiple lesions. At the time of diagnosis, the majority of patients (n=68) were in stages I-II. A new endoscopic classification of PSIL was developed, including hypertrophic type, exophytic type, follicular/polypoid type, ulcerative type, and diffusion type. Surgery did not show a significant increase in overall survival; chemotherapy was the most commonly administered treatment. T-cell lymphoma, stages III-IV, "B" symptoms, and ulcerative type were associated with poor prognosis. Conclusion: This study provides a comprehensive analysis of the clinical and endoscopic features of PSIL in 94 patients. This highlights the importance of considering clinical and endoscopic characteristics for accurate diagnosis and prognosis estimation during small bowel enteroscopy. Early detection and treatment of PSIL is associated with a favorable prognosis. Our findings also suggest that certain risk factors, such as pathological type, "B" symptoms, and endoscopic type, may affect the survival of PSIL patients. These results underscore the need for careful consideration of these factors in the diagnosis and treatment of PSIL.
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BACKGROUND: Polymerase chain reaction (PCR) has been widely used for many pathogen detection. However, PCR technology still suffers from long detection time and insufficient sensitivity. Recombinase-aided amplification (RAA) is a powerful nucleic acid detection tool with high sensitivity and amplification efficiency, but its complex probes and inability of multiplex detection hinder the further application of this technology. METHODS: In this study, we developed and validated the multiplex reverse transcription recombinase-aided PCR (multiplex RT-RAP) assay for human adenovirus 3 (HADV3), human adenovirus 7 (HADV7), and human respiratory syncytial virus (HRSV) within 1 h with Human RNaseP protein as a reference gene to monitor the whole process. RESULTS: Using recombinant plasmids, the sensitivity of multiplex RT-RAP for the detection of HADV3, HADV7, and HRSV was 18, 3, and 18 copies per reaction, respectively. The multiplex RT-RAP showed no cross-reactivity with other respiratory viruses, demonstrating its good specificity. A total of 252 clinical specimens were tested by multiplex RT-RAP and the results were found to be consistent with those of corresponding RT-qPCR assays. After testing serial dilutions of selected positive specimens, the detection sensitivity of multiplex RT-RAP was two to eightfold higher than that of corresponding RT-qPCR. CONCLUSION: We conclude the multiplex RT-RAP is a robust, rapid, highly sensitive, and specific assay with the potential to be used in the screening of clinical samples with low viral load.
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Adenovírus Humanos , Vírus Sincicial Respiratório Humano , Humanos , Vírus Sincicial Respiratório Humano/genética , Adenovírus Humanos/genética , Transcrição Reversa , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Reação em Cadeia da Polimerase Multiplex , Sensibilidade e EspecificidadeRESUMO
Objectives: The World Health Organization (WHO) Global tuberculosis Report 2021 stated that rifampicin-resistant tuberculosis (RR-TB) remains a major public health threat. However, the in-practice diagnostic techniques for RR-TB have a variety of limitations including longer time, lack of sensitivity, and undetectable low proportion of heterogeneous drug resistance. Methods: Here we developed a multiplex LNA probe-based RAP method (MLP-RAP) for more sensitive detection of multiple point mutations of the RR-TB and its heteroresistance. A total of 126 clinical isolates and 78 sputum samples collected from the National Tuberculosis Reference Laboratory, China CDC, were tested by MLP-RAP assay. In parallel, qPCR and Sanger sequencing of nested PCR product assay were also performed for comparison. Results: The sensitivity of the MLP-RAP assay could reach 5 copies/µl using recombinant plasmids, which is 20 times more sensitive than qPCR (100 copies/µl). In addition, the detection ability of rifampicin heteroresistance was 5%. The MLP-RAP assay had low requirements (boiling method) for nucleic acid extraction and the reaction could be completed within 1 h when placed in a fluorescent qPCR instrument. The result of the clinical evaluation showed that the MLP-RAP method could cover codons 516, 526, 531, and 533 with good specificity. 41 out of 78 boiled sputum samples were detected positive by MLP-RAP assay, which was further confirmed by Sanger sequencing of nested PCR product assay, on the contrary, qPCR was able to detect 32 samples only. Compared with Sanger sequencing of nested PCR product assay, both the specificity and sensitivity of the MLP-RAP assay were 100%. Conclusion: MLP-RAP assay can detect RR-TB infection with high sensitivity and specificity, indicating that this assay has the prospect of being applied for rapid and sensitive RR-TB detection in general laboratories where fluorescent qPCR instrument is available.
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Human immunodeficiency virus 1 (HIV-1) attacks the immune system, making people susceptible to various diseases, thus increasing their risk of death. Comprehensive detection of major HIV-1 strains circulating in China is vital for effective HIV-1 infection prevention and treatment. HIV-1 nucleic acid detection is considered effective for HIV-1 diagnosis since traditional immunological testing may fail to detect HIV-1 infection during the window period. This work demonstrates a one-pot two-stage amplification assay (RT-RAP), a combination of reverse transcription recombinase (RT- RAA), and quantitative real-time polymerase chain reaction (qRT-PCR). The turn-around time of the assay is only 50 min and can be performed with commonly available laboratory equipment, the qPCR devices. The RT-RAP assay could detect approximately 5 and 14 copies/reaction of HIV-1 DNA and RNA using recombinant plasmids and standard reference strains, respectively. Additionally, we found that the clinical performance of RT-RAP (detected 169 samples out of 170 specimens) was consistent with that of qRT-PCR. The sensitivity and specificity of RT-RAP were 100.00% (99/99) and 98.59% (70/71), respectively, while its positive and negative predictive values were 99.00% (99/100) and 100.00% (70/70), respectively. The total coincidence rate of the RT-RAP was 99.41% (169/170), with a kappa value of 0.988 (p < 0.05). We demonstrated that RT-RAP could rapidly detect the common HIV-1 subtypes commonly circulating in China with comparable sensitivity and specificity to qRT-PCR.
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BACKGROUND: Pneumonia caused by Mycoplasma pneumoniae is common in the elderly and children, and pneumonia caused by Chlamydia trachomatis is prevalent in newborns. This study aimed to establish a rapid, sensitive, and simple method for the direct detection of M. pneumoniae and C. trachomatis in clinical samples without DNA extraction. METHODS: We established a duplex recombinase-aided amplification (RAA) assay with the RNAseP gene as an internal control for detecting the P1 gene of M. pneumoniae and the ORF8 gene of C. trachomatis, respectively. The results were obtained at 39 °C within 15-20 min. A total of 130 clinical samples suspected of M. pneumoniae or C. trachomatis infection were collected and tested by duplex RAA and PCR. DNA extracted via a commercial kit or treated with a nucleic acid-releasing agent was used and compared, respectively. Standard recombinant plasmids were used to test the sensitivity of the duplex RAA assay. In addition, other similar common pathogens were used to verify the specificity of the duplex RAA assay. RESULTS: The sensitivity of the duplex RAA assay for detecting M. pneumoniae and C. trachomatis was 10 copies/µL using recombinant plasmids. Compared with PCR, the sensitivity and specificity of duplex RAA assays for M. pneumoniae and C. trachomatis was 100% using clinical DNA samples extracted using a commercial kit and a nucleic acid-releasing agent, and the Kappa value was 1. CONCLUSION: The advantages of this duplex RAA assay include high sensitivity and specificity, short duration, and simple extraction steps, with potential for use in the on-site detection of M. pneumoniae and C. trachomatis in resource-limited settings.
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Ácidos Nucleicos , Recombinases , Idoso , Criança , Chlamydia trachomatis/genética , Humanos , Recém-Nascido , Mycoplasma pneumoniae/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Sensibilidade e EspecificidadeRESUMO
Background and study aims Bleeding is a common complication of following endoscopy sphincterotomy (EST), and antithrombotic therapy use during the procedure often increases risk of it. Although several guidelines have been released regarding the use of antithrombotic agents during EST, many issues about it remain controversial. We carried out a systematic review and meta-analysis to evaluate the effect of antithrombotic medication on the risk of EST bleeding. Methods A structured literature search was carried out in Web of Science, EMBASE, PubMed, and Cochrane Library databases. RevMan 5.2 was used for meta-analysis to investigate the rate of post-EST bleeding. Results Seven retrospective articles were included. Compared with patients who had never taken antithrombotic drugs, patients who discontinued antithrombotic drugs 1 day before the procedure had a significantly increased risk of post-EST bleeding (OR, 1.95; 95â%CI, 1.57-2.43), particularly for severe bleeding (OR, 1.83; 95â%CI, 1.44-2.34). In addition, compared with patients who discontinued antithrombotic therapy for at least 1 day, patients who continued taking antithrombotic drugs did have an increased risk of post-EST bleeding (OR, 0.70; 95â%CI, 0.40-1.23). Conclusions The use of antithrombotic drugs may increase the bleeding rate of EST, but discontinuing therapy 1 day before endoscopy does not significantly reduce the bleeding rate.
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Epstein-Barr virus (EBV), a common human γ-herpesvirus, infects more than 90% of adults worldwide. The purpose of this study was to establish a novel EBV detection method by combining the recombinase aided amplification (RAA) assay with an initial enrichment step that utilizes magnetic beads coated with a recombinant human mannan-binding lectin (rhMBL, M1 protein). An M1 protein-protein A magnetic bead complex (M1 beads) was prepared and used to achieve separation and enrichment of EBV from blood. After nucleic acid extraction, DNA was amplified by RAA. Using 388 whole blood samples and 1 serum sample, we explored the specificity, sensitivity and applicability of the newly developed detection method and compared it with commercial quantitative real-time polymerase chain reaction (qPCR) following M1 bead enrichment, traditional qPCR and traditional RAA. After enrichment, the positivity rate of EBV was increased from 15.94% to 17.74% by RAA (P < 0.05) and from 7.20% to 15.17% by qPCR (P < 0.05). The viral loads after enrichment were increased by 1.13 to 23.19-fold (P < 0.05). Our data demonstrates that an RAA assay incorporating M1 bead enrichment is a promising tool for detecting low EBV viral loads in blood samples that will facilitate an early response to EBV infection.
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Recombinase aided amplification (RAA) is an emerging isothermal amplification method used for detecting various pathogens. However, RAA requires a complex and long probe to ensure high sensitivity during fluorescence assay. TaqMan probe used for quantitative PCR (qPCR) is simple and universal. Herein, we developed a new approach for detecting nucleic acids of pathogens, known as RAP (Recombinase aided PCR). The method combines RAA and qPCR to ensure a rapid and highly sensitive detection using a conventional qPCR device. RAP is a two-stage amplification process performed in a single tube within 1 hour. The method involves an RAA reaction for 10 min at 39°C (first stage) followed by 15 cycles of qPCR (second stage). Using human adenovirus 3 (HADV3) and human adenovirus 7 (HADV7) plasmids, the sensitivities of RAP assays for detecting HADV3 and HADV7 were 6 and 17 copies per reaction, respectively. The limit of RAP detection was at least 16-fold lower than the corresponding qPCR, and no-cross reaction with other respiratory viruses was observed. The results of RAP analysis revealed 100% consistency with qPCR assay. This study shows that RAP assay is a rapid, specific, and highly sensitive detection method with a potential for clinical and laboratory application.
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OBJECTIVES: To evaluate whether amide proton transfer (APT) MRI can be used to characterize gliomas in pediatric patients and whether it provides added value beyond relaxation times. METHODS: In this prospective study, APT imaging and relaxation time mapping were performed in 203 pediatric patients suspected of gliomas from February 2018 to December 2019. The region of interest (ROI) in the tumor was automatically generated with artifact detection and ROI-shrinking algorithms. Several APT-related metrics (CESTR, CESTRnr, MTRRex, AREX, and APT#) and quantitative T1 and T2 were compared between low-grade and high-grade gliomas using the student's t-test or Mann-Whitney U-test. The performance of these parameters was assessed using the receiver operating characteristic (ROC) analysis. A stepwise multivariate logistic regression model was used to combine the imaging parameters. RESULTS: Forty-eight patients (mean age: 6 ± 4 years; 23 males and 25 females) were included in the final analysis. All the APT-related metrics except APT# had significantly (p < 0.05) higher values in the high-grade group than the low-grade group. Under different ROI-shrinking cutoffs, the quantitative T1 (p = 0.045-0.200) and T2 (p = 0.037-0.171) values of high-grade gliomas were typically lower than those of low-grade ones. The stepwise multivariate logistic regression revealed that CESTRnr and APT# were combined significant predictors of glioma grades (p < 0.05), with an area under the ROC curve (AUC) of 0.86 substantially larger than those of T1 (AUC = 0.69) and T2 (AUC = 0.68). CONCLUSIONS: APT imaging can be used to differentiate high-grade and low-grade gliomas in pediatric patients and provide added value beyond quantitative relaxation times. KEY POINTS: ⢠Amide proton transfer (APT) MRI showed significantly (p < 0.05) higher values in pediatric patients with high-grade gliomas than those with low-grade ones. ⢠The area under the curve was 0.86 for APT MRI to differentiate low-grade and high-grade gliomas in pediatric patients, which was substantially higher than that for quantitative T1 (0.69) and T2 (0.68). ⢠APT MRI demonstrated added value beyond quantitative T1 and T2 mapping in characterizing pediatric gliomas.
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Neoplasias Encefálicas , Glioma , Amidas , Neoplasias Encefálicas/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Glioma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Gradação de Tumores , Estudos Prospectivos , PrótonsRESUMO
Manganese oxides (MnO2) are widely applied in heavy metal ions removal due to their low-cost, environmental-friendly and biocompatibility. However, the adsorption capacity of MnO2 need to be further improved to satisfy the demand of practical application. Herein, a highly dispersed single layer NaxKyMnO2 nanosheet was synthesized by a facile wet-chemical method with sodium dodecyl sulfonate as surfactant. The high surface specific area, excellent dispersibility and abundant oxygen vacancies endowed NaxKyMnO2 nanosheets with potential in heavy metal ions adsorption. The adsorption experiments results showed that NaxKyMnO2 nanosheets possessed high efficiency and selectivity towards lead ion (Pb2+) with a high adsorption capacity of 2091.8 µmol g-1. The NaxKyMnO2 also showed an excellent reusability with the removal rate of 95.4% for Pb2+ even after five cycles. Moreover, both the theoretical calculation and experimental data illustrated that the single layer NaxKyMnO2 nanosheets possess high selectivity to Pb2+ adsorption.
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Metais Pesados , Poluentes Químicos da Água , Adsorção , Íons , Cinética , Compostos de Manganês , Modelos Teóricos , Óxidos , Sódio , Poluentes Químicos da Água/análiseRESUMO
There are challenges in developing multifunctional materials that can not only effectively adsorb but also completely eliminate organic contaminants in water. In this work, novel ZnO/biochar nanocomposites were synthesized using a facile ball-milling method. A series of characterization results showed that the ZnO nanoparticles dispersed uniformly on carbon surface within the biochar matrix. Ball milling increased the mesopores and macropores of the nanocomposites by breaking biochar and squeezing ZnO. The addition of appropriate amount of ZnO into biochar enhanced both the adsorption capacity and photocatalytic ability of the nanocomposites for methylene blue (MB) removal. When the initial concentration of MB was 160 mg/g, the nanocomposites exhibited high MB removal efficiency (up to 95.19%) under visible light through the combination of adsorption and photocatalysis. This work provides a feasible synthesis of metal oxide/biochar nanocomposites with excellent adsorption and photocatalysis properties for the treatment of organic dye wastewater.
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Colorimetric aptasensors have been intensively studied for the ochratoxin A (OTA) detection, but they mostly exhibit just one-color change, resulting in poor visual resolution and limited use for semi-quantitative analysis. Thus, we designed a high-resolution colorimetric assay on the basis of aptamer structural switching and enzyme-induced metallization of gold nanorods (AuNRs). DNA-alkaline phosphatase (ALP)-immobilized magnetic beads were prepared. The aptamer bounded to OTA to form G-quadruplexes, releasing ALP-labelled complementary DNA (cDNA-ALP). After magnetic separation, cDNA-ALP catalyzed the decomposition of ascorbic acid 2-phosphate to ascorbic acid that reduced Ag+, forming an Ag shell on the surface of AuNRs. This caused a blue-shift of the longitudinal local surface plasmon resonance peak of the AuNRs and a naked eye visible multicolor change. Under optimal conditions, the assay exhibited a 9.0 nM detection limit for OTA, with high specificity. This method is promising for the on-site visual semi-quantitative detection of mycotoxins in foods.
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Fosfatase Alcalina/metabolismo , Aptâmeros de Nucleotídeos/química , Colorimetria/métodos , Nanotubos/química , Ocratoxinas/análise , Quadruplex G , Ouro/química , Separação Imunomagnética , Limite de Detecção , Ressonância de Plasmônio de SuperfícieRESUMO
The main mechanism of hyaluronidase 1(HYAL-1) in the development of postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD) was unknown. In this study, a comprehensive inventory of pre-, intra-, and postoperative clinical and biological data of two cohorts (62 pancreatic cancer [PCa] and 111 pancreatic ductal adenocarcinoma [PDAC]) which could induce POPF were retrospectively analyzed. Then, a total of 7644 genes correlated with HYAL-1 was predicted in PDAC tissues and the enriched pathway, kinase targets and biological process of those correlated genes were evaluated. Finally, a mouse pancreatic fistula (PF) model was first built and in vitro studies were performed to investigate the effects of HYAL-1 on PF progression. Our data indicated that preoperative serum HYAL-1 level, pancreatic fibrosis score, and pancreatic duct size were valuable factors for detecting POPF of Grade B and C. The serum HYAL-1 level of 2.07 mg/ml and pancreatic fibrosis score of 2.5 were proposed as the cutoff values for indicating POPF. The bioinformatic analysis and in vitro and in vivo studies demonstrated that HYAL-1 facilitates pancreatic acinar cell autophagy via the dephosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK) and signal transducers and activators of transcription 3 (STAT3) signaling pathways, which exacerbate pancreatic secretion and inflammation. In summary, the preoperative serum HYAL-1 was a significant predictor for POPF in patients who underwent PD. Tumor-induced HYAL-1 is one of core risk in accelerating PF and then promoting pancreatic secretion and acute inflammation response through the AMPK and STAT3-induced autophagy.