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Removal of Mn(II) is an essential step for addressing water discoloration in water treatment utilities worldwide. However, conventional chlorination suffers from poor oxidation of Mn(II) due to its low homogeneous oxidation kinetics. This study explored the oxidation capability of a new chemical dosing strategy employing peroxymonosulfate (PMS) to assist the chlorination process (PMS@Cl2) for effective Mn(II) oxidation. The study comprehensively explored both oxidation kinetics and underlying mechanisms associated with homogeneous and heterogeneous oxidation within the PMS@Cl2 system. At an [Mn(II)]0 of 1 mg/L, chlorination demonstrated inability in oxidizing Mn(II), with <10 % oxidation even at an elevated [Cl2] of 150 µM (â¼10 mg/L). By contrast, PMS completely oxidized 100 % Mn(II) within a 30-minute reaction at a much lower [PMS] of 60 µM (kobs = 0.07 min-1 and t1/2 = 9 min), demonstrating its superior Mn(II) oxidation kinetics (over one order of magnitude faster than conventional chlorine). PMS@Cl2 exhibited an interesting synergistic benefit when combining a lower dose PMS with a higher routine dose Cl2 (loPMS@hiCl2), e.g. [PMS]:[Cl2] at 15:30 or 30:30 µM. Both conditions achieved 100 % Mn(II) oxidation, with even better values of kobs and t1/2 (0.16-0.17 min-1 and â¼4 min) relative to PMS alone at 60 µM. The synergic benefit of PMS@Cl2 was attributed to distinct functions played by PMS and Cl2 in both homogeneous and heterogeneous oxidation processes. Reactive species identification excluded the possible involvement of SO4â¢-, OHâ¢, or chlorine radicals in the homogeneous oxidation of the PMS@Cl2 system. Instead, the dominant species was O2â¢- radical generated during the reaction of Mn(II) and PMS. Furthermore, the heterogeneous oxidation emphasized the important role of combining Cl2 dosing, which demonstrated an increased reactivity and electron transfer with the Mn-O-Mn complex, surpassing PMS. Overall, heterogeneous oxidation accelerated the oxidation kinetics of the PMS@Cl2 system by 1.1-2 orders of magnitude relative to the homogeneous oxidation of Cl2 alone. We here demonstrated that PMS@Cl2 could offer a more efficient mean of soluble Mn(II) mitigation, achieved with a relatively low routine dose of oxidant in a short reaction period. The outcomes of this study would address the existing limitations of traditional chlorine oxidation, minimizing the trade-offs associated with high residual chlorine levels after treatments for soluble manganese-containing water.
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BACKGROUND: This study evaluated the impact of the tax increase in January 2019 on changes in intention to quit and the effect of cigarette prices on quit attempts and successful quitting among male cigarette smokers in Vietnam. METHODS: Data were derived from the ITC project in Vietnam, which included 1585 adult smokers at baseline (Wave 1, Aug-Oct 2018) followed up to waves 2 (Sep-Nov 2019) and 3 (Sep-Dec 2020). Generalized estimating equations regression was performed to estimate changes in the intention to quit. Multiple logistic regression analysis was used to evaluate the cigarette price of a cigarette pack in relation to quit attempts and successful quitting. RESULTS: The increase in cigarette tax in 2019 did not significantly increase the likelihood of the intention to quit. After the tax increase, 63.6% of participants who smoked made a quit attempt, and 27.6% successfully quit smoking in the follow-up waves. However, the price of a cigarette pack was not significantly associated with quit attempts and successful quitting. The study did not observe a significant impact of cigarette prices on quit attempts and successful quitting in all subgroups of household income. Factors associated with quit attempts included the number of cigarettes smoked and the intention to quit, while those associated with successful quitting included age, dual use of cigarettes and other tobacco products, and the intention to quit. CONCLUSION: Current cigarette prices were not associated with cessation behaviors even within the lowest household income group. Therefore, a sharp rise in cigarette tax is required to incentivize smokers to quit smoking.
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Comércio , Abandono do Hábito de Fumar , Impostos , Produtos do Tabaco , Humanos , Masculino , Vietnã , Abandono do Hábito de Fumar/economia , Abandono do Hábito de Fumar/estatística & dados numéricos , Abandono do Hábito de Fumar/psicologia , Adulto , Produtos do Tabaco/economia , Pessoa de Meia-Idade , Comércio/estatística & dados numéricos , Impostos/estatística & dados numéricos , Intenção , Fumantes/estatística & dados numéricos , Fumantes/psicologia , Adulto Jovem , Inquéritos e Questionários , AdolescenteRESUMO
Dissolved organic matter (DOM) in landfill leachate impacts the toxicity, bioavailability, and migration of heavy metals. The present study investigated the complexation of heavy metals (Cu2+ and Pb2+) with DOM from two landfill leachate samples, representing an old landfill site containing incineration residues and incombustible waste. The logarithms of the stability constant (log KM) and percentage of complexed fluorophores were calculated using both the Ryan-Weber non-linear model and the modified Stern-Volmer model, yielding good agreement. The log KM values (at pH = 6.0 ± 0.1) calculated using both methods for the two sampling points were 5.02-5.13 and 4.85-5.11 for Cu2+-DOM complexation, and 5.01-5.13 and 4.46-4.87 for Pb2+-DOM complexation, respectively. Log KM was slightly higher for binding of DOM with Cu2+ than Pb2+, and the quenching degree was stronger for complexation with Cu2+ (28.5-30.6% and 38.0-45.9%) than Pb2+ (6.5-7.1% and 10.0-15.4%) in both leachate samples. While log KM values were similar, differences in the contributions of functional groups and molecular composition led to varying degrees of quenching. This study reveals the potential for heavy metal binding by DOM in landfill leachate with a unique solid waste composition and emphasizes variations in fluorescence quenching between Cu2+ and Pb2+ despite similar log KM levels. These findings may be useful for assessing heavy metal behavior in landfill leachate and its impacts on the surrounding environment.
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The ability to predict or detect colorectal cancer (CRC) recurrence early after surgery enables physicians to apply appropriate treatment plans and different follow-up strategies to improve patient survival. Overall, 30-50% of CRC patients experience cancer recurrence after radical surgery, but current surveillance tools have limitations in the precise and early detection of cancer recurrence. Circulating tumor cells (CTCs) are cancer cells that detach from the primary tumor and enter the bloodstream. These can provide real-time information on disease status. CTCs might become novel markers for predicting CRC recurrence and, more importantly, for making decisions about additional adjuvant chemotherapy. In this review, the clinical application of CTCs as a therapeutic marker for stage II CRC is described. It then discusses the utility of CTCs for monitoring cancer recurrence in advanced rectal cancer patients who undergo neoadjuvant chemoradiotherapy. Finally, it discusses the roles of CTC subtypes and CTCs combined with clinicopathological factors in establishing a multimarker model for predicting CRC recurrence.
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Hydrogen peroxide (H2O2) production via oxygen (O2) reduction reaction (ORR) in pure water (H2O) through graphitic carbon nitrides (g-C3N4)-based piezo-photocatalysts is an exciting approach in many current studies. However, the low Lewis-acid properties of g-C3N4 limited the catalytic performance because of the low O2 adsorption efficacy. To overcome this challenge, the interaction of g-C3N4 precursors with various solvents are utilized to synthesize g-C3N4, possessing multiple nitrogen-vacant species via thermal shocking polymerization. These results suggest that the lack of nitrogen in g-C3N4 and the incident introduction of oxygen-functional groups enhance the Lewis acid-base interactions and polarize the g-C3N4 lattices, leading to the enormous enhancement. Furthermore, the catalytic mechanisms are thoroughly studied, with the formation of H2O2 proceeding via radical and water oxidation pathways, in which the roles of light and ultrasound are carefully investigated. Thus, these findings not only reinforce the potential view of metal-free photocatalysts, accelerating the understanding of g-C3N4 working principles to generate H2O2 based on the oxygen reduction and water oxidation reactions, but also propose a facile one-step way for fabricating highly efficient and scalable photocatalysts to produce H2O2 without using sacrificial agents, pushing the practical application of in situ solar H2O2 toward real-world scenarios.
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Elucidating the properties of landfill leachate and the relationships among leachate parameters is crucial for efforts to determine appropriate landfill leachate monitoring activity and management strategies. This study investigated the physical, chemical and optical parameters of leachate in an old Japanese landfill over a 13-month period. The parameters were explored based on their relationships with the maximum fluorescence (Fmax) of three components (microbial humic-like C1, terrestrial humic-like C2 and protein-like C3) deconvoluted from excitation-emission matrix fluorescence spectroscopy coupled with parallel factor analysis. Dissolved organic carbon (DOC), chemical oxygen demand (COD), Cl- and SO42- concentrations and pH ranged from 2.6 to 38.2 mg C L-1, 9 to 324 mg L-1, 14 to 972 mg L-1, 26 to 1554 mg L-1 and 6.9 to 11.6, respectively. Linear regression analysis suggested that the Fmax values of C2 and C3 represented DOC, whereas the Fmax value of C2 alone could serve as a COD indicator. Hierarchical cluster analysis and principal component analysis were employed to successfully categorise leachate samples based on their locations. Higher dissolved organic matter levels were observed in leachate within the old disposal area, whereas elevated levels of inorganic components such as SO42- and Cl- were found in leachate collected from the extended disposal area and at a treatment facility. Statistical analysis provides crucial tools for assessing and managing various areas of a landfill, supporting targeted and effective waste management strategies.
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Dissolved organic matter (DOM) influences the bioavailability and behavior of trace metals and other pollutants in landfill leachate. This research characterized fluorescent dissolved organic matter (FDOM) in leachate from an old landfill in Japan during a 13-month investigation. We employed excitation-emission matrix (EEM) fluorescence spectroscopy with parallel factor analysis (PARAFAC) to deconvolute the FDOM complex mixture into three fluorophores: microbial humic-like (C1), terrestrial humic-like (C2), and tryptophan-like fluorophores (C3). These FDOM components were compared with findings from other studies of leachate in landfills with different waste compositions. The correlations among EEM-PARAFAC components, dissolved organic carbon (DOC) concentration, and ultraviolet-visible and fluorescence indices were evaluated. The FDOM in leachate varied spatially among old and extended leachate collected in the landfill and leachate treatment facility. The FDOM changed temporally and decreased markedly in August 2019, November 2019, and April 2020. The strong positive correlation between HIX and %C2 (r = 0.87, ρ = 0.91, p < 0.001)) implies that HIX may indicate the relative contribution of terrestrial humic-like components in landfill leachate. The Fmax of C1, C2, and C3 and the DOC concentration showed strong correlations among each other (r > 0.72, ρ > 0.78, p < 0.001) and positive correlations with leachate level (r > 0.41, p < 0.001), suggesting the importance of hydrological effects and leachate pump operation on FDOM.
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Instalações de Eliminação de Resíduos , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Espectrometria de Fluorescência/métodos , Incineração , Japão , Substâncias Húmicas/análise , Fluorescência , Monitoramento Ambiental/métodosRESUMO
AIM: To explore the health beliefs and health behaviours of older Vietnam-born people living with chronic disease in Western Australia. DESIGN: This study was designed as a focused ethnography guided by the interpretative research paradigm and Leininger's Theory of Culture Care. METHODS: Data were collected through participant observation and interviews undertaken at participants' homes in Western Australia over 7 months in 2019. Data were analysed using Wolcott's approach for transferring qualitative data, comprising three phases: description, thematic analysis and interpretation. RESULTS: This study included 12 participants. The health perspectives and practices of older Vietnam-born Australians significantly reflected the traditional Vietnamese values. These included the stigma towards chronic disease as an inevitable consequence of ageing; self-blame thoughts about chronic disease causations and maintained traditional dietary practices. However, some aspects of their health behaviours such as beliefs and practices in traditional medicine, Western medicine and physical exercise reflected a blended approach combining both Vietnamese-oriented and Westernized-orientated practices. Individual factors were also identified as contributing to chronic disease self-care among participants. CONCLUSION: This study emphasizes culture played a significant role in shaping the way that older Vietnam-born Australians believed and behaved while living with chronic conditions. However, it also indicates that culture is not a stationary concept, it evolves gradually and is socially constructed. IMPLICATIONS: A better understanding of the health beliefs and practices of older Vietnam-born Australians is expected to contribute to the delivery of culturally safe and effective support for this population. The achievement of culturally safe care requires a systemic approach and collaboration of strategies across sectors. PATIENT AND PUBLIC CONTRIBUTION: This study encompassed the contribution of 12 older Vietnam-born Australians who offered the researcher the privilege to enter their world and the staff of social care organization who opened the gate for the researcher to approach participants.
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Comportamentos Relacionados com a Saúde , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Austrália , Doença Crônica/psicologia , Doença Crônica/etnologia , Comportamentos Relacionados com a Saúde/etnologia , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Pesquisa Qualitativa , Vietnã/etnologia , Austrália Ocidental , População do Sudeste AsiáticoRESUMO
INTRODUCTION: Understanding smokers' purchasing patterns can aid in customizing tobacco control initiatives aimed at reducing the tobacco smoking prevalence. Therefore, this study identified cigarette purchase behavior among Vietnamese male smokers and associated demographic and consumption factors. METHODS: We analyzed a secondary dataset of male current tobacco smokers (n=3983) who participated in the Vietnam Global Adult Tobacco Survey in 2015. We applied the latent class analysis (LCA) to identify the classes of purchase behavior among cigarette smokers (n=1241). Multinomial logistic regression was performed to identify demographics (education level, ethnicity, partnership status, and household socioeconomic status) and cigarette consumption variables (smoking years and heavy smoking status) related to purchase behavior classes. The results are reported as an adjusted relative risk ratio (ARRR). RESULTS: The LCA identified four cigarette purchase behaviors classes: Class 1 (price-insensitive and purchased international brand: 44.4%), Class 2 (price-sensitive and purchased domestic brand: 27.6%), Class 3 (price-sensitive and purchased cigarettes in a street vendor: 18.6%), and Class 4: price-sensitive and purchased loose/carton cigarette: 9.4%). The poorer economic groups were more likely to belong to the three price-sensitive classes. Heavy smokers and those who had smoked for a longer period were more likely to belong to Class 3 (ARRR=2.33; 95% CI: 1.51-3.58 and ARRR=1.02; 95% CI: 1.001-1.05, respectively) and Class 4 (ARRR=2.94; 95% CI: 1.71-5.06 and ARRR=1.05; 95% CI: 1.02-1.08, respectively). CONCLUSIONS: Varied purchasing behaviors among male cigarette smokers, influenced by divergent price sensitivities and economic backgrounds, underscore the need for comprehensive tobacco control. Future efforts should include targeted policy interventions, behavior modification, and reshaping social norms.
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Background: Trans women in Vietnam are among the most vulnerable groups with high HIV risk and limited access to care. TransAction is an evidence-based intervention to reduce trans women's HIV risks and increase social support and access to care.Aims: The aim of this study was to adapt TransAction to the specific needs of trans women in Vietnam. Methods: This study was conducted in Ho Chi Minh City from November 2020 through June 2021 Using the ADAPT-ITT framework, interviews, focus groups, and community advisory board meetings were conducted with trans women, service providers, and community members to better understand Vietnamese contexts of gender transition, HIV risks, and service gaps. Feedback was solicited on TransAction content and format adaptation. Results: Trans women in Vietnam faced unique challenges related to family norms, policy and regulatory constraints, and limited transgender-specific or gender-inclusive services. TransAction was modified to accommodate identified challenges and needs, and intervention components to enhance family support were added. Strategies to cope with stigma and seek support and services were adapted to Vietnamese culture and policies. Discussion: Post-adaptation interviews and focus groups demonstrated strong feasibility and acceptability for the adapted intervention, which can potentially be used to reduce Vietnamese trans women's HIV risks and increase their social support.
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Background: Infection causes cirrhosis to decompensate, affecting liver function and resulting in several complications, including esophageal variceal hemorrhage, hepatic encephalopathy, and hepatorenal syndrome. Objective: This study aimed to identify the prevalence, essential features, and related factors of bacterial infection among patients with cirrhosis in Vietnam. Methods: This retrospective study included 317 patients diagnosed with cirrhosis, who were divided into two groups: group 1 including 125 patients with bacterial infection and group 2 including 192 patients without bacterial infection. Infection was diagnosed on the basis of its localization. Results: Spontaneous bacterial peritonitis (SBP; 31.2%) and pneumonia (28.8%) were the most common infections identified. The procalcitonin (PCT) level had a strong diagnostic value with an area under the curve value of 0.868. The most common type of gram-negative bacteria was Escherichia coli, while the gram-positive bacteria seen were Staphylococcus, Enterococcus, and Streptococcus among the patients with infection. In the logistic regression analysis, Child-Pugh class B and C (p<0.001, OR=4.14, CI=1.90-9.03; OR=4.76, CI=2.03-11.16, respectively) and the presence of acute kidney injury (p=0.009, OR=2.57, CI=1.27-5.22) and gastrointestinal hemorrhage (p=0.035, OR=0.39, CI=0.16-0.94) significantly differed between the groups. Conclusion: The most prevalent type of bacterial infection in patients with cirrhosis is SBP, with gram-negative bacteria being the most common cause. The PCT level is useful in identifying infection in patients with cirrhosis. Decompensated cirrhosis is linked to a higher risk of infection.
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The inhibitory effect against 5-α reductase of the ethyl acetate (EA) extract from Physalis angulata was evaluated in vitro using mouse prostate homogenates, and the suppression of benign prostatic hyperplasia (BPH) was assessed in a mouse model of testosterone-induced BPH. The EA extract exhibited a potentially inhibitory effect on 5-α reductase with an IC50 of 197 µg/ml. In BPH mice, the EA extract at a dose of 12 mg/kg was comparable to finasteride 5 mg/kg in suppressing BPH in terms of reducing absolute enlarged prostate weight (p < 0.05 vs. BPH group) and mitigating the hypertrophy of glandular elements and prostate connective tissue. Identification of chemical ingredients in the EA extract by UPLC-QTOF-MS revealed 37 substances belonging chiefly to flavonoids and physalins. Further quantification of the EA extract by HPLC-PDA methods revealed that chlorogenic acid, and rutin were the main components. Molecular docking studies of chlorogenic acid and rutin on 5-α reductase showed their high affinity to the enzyme with binding energies of -9.3 and - 9.2 kcal/mol, respectively compared with finasteride (- 10.3 kcal/mol). Additionally, chlorogenic acid inhibited 5-α reductase with an IC50 of 12.07 µM while rutin did not. The presence of chlorogenic acid in the EA extract may explain the inhibitory effects of the EA extract on 5-α reductase, and thus the suppression of BPH.
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Inibidores de 5-alfa Redutase , Simulação de Acoplamento Molecular , Physalis , Extratos Vegetais , Hiperplasia Prostática , Animais , Hiperplasia Prostática/tratamento farmacológico , Masculino , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Camundongos , Physalis/química , Inibidores de 5-alfa Redutase/farmacologia , Inibidores de 5-alfa Redutase/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Estrutura Molecular , Ácido Clorogênico/farmacologia , Ácido Clorogênico/isolamento & purificação , Próstata/efeitos dos fármacos , Modelos Animais de DoençasRESUMO
OBJECTIVES: To describe the status of using biological Disease Modifying Anti Rheumatic Drugs (bDMARDs) to treat rheumatoid arthritis (RA) and related factors. In addition, the study determined the impact of COVID-19 on the usage of bDMARDs. METHODS: This is a cross-sectional study and included 219 RA patients over 18 years old. The Kaplan-Meier method and the log-rank test (p<0.05) were used to estimate the retention time and compare between different times. Cox regression analysis was used to determine the factors affecting the retention time of biological drugs (p<0.05). RESULTS: Out of 1967 courses of treatment, there were 149 (7.6%) drug discontinuations, 760 (38.6%) doses extensions and 64 (3.3%) drug switch. Moderate disease level and choosing tumor necrosis factor (TNF) inhibitors initially were associated with retention time of COVID-19. Drug discontinuations and dose extensions increased after COVID-19 emergence. The retention time during COVID-19 was significantly different from that of pre-COVID-19. Gender, type of first-used bDMARD, conventional synthetic DMARDs (csDMARDs) and corticoid usage status, disease activity levels were associated with retention time. CONCLUSION: The presence of COVID-19 has a significant effect on usage status of the biologic drug. Further longitudinal studies are needed to clarify the relationship between COVID-19 and drug usage as well as related factors.
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Antirreumáticos , Artrite Reumatoide , Produtos Biológicos , COVID-19 , Humanos , Adolescente , Vietnã , Estudos Transversais , Artrite Reumatoide/tratamento farmacológico , Antirreumáticos/uso terapêutico , Produtos Biológicos/uso terapêuticoRESUMO
A new cucurbitacin, 3ß-(ß-D-glucopyranosyloxy)-5ß,6ß:16α,23α-diepoxycucurbit-24-en-11-one or hygrocucurbin A (1), along with two known compounds, including 3ß-(ß-D-glucopyranosyloxy)-16α,23α-epoxycucurbita-5,24-dien-11-one (2) and (+)-lyoniresinol (3), were isolated from the bark of Elaeocarpus hygrophilus. Their chemical structures were elucidated by spectroscopic NMR, HR-IDA- TOF-MS analysis, and by comparison with the spectral data of corresponding compounds in the literature. Two cucurbitacins (1) and (2) were evaluated for their α-glucosidase inhibitory activity and cytotoxic against KB, MCF-7, Hep G2, and A549 cancer cell lines. For the α-glucosidase inhibitory activity, compound 1 showed an equivalent effect (IC50 197.4 ± 4.1 µM) compared to the acarbose, a positive control (IC50 208.5 ± 4.7 µM). And for the cytotoxicity, 2 was inactive while 1 was slightly sensitive against KB cells (IC50 233.3 ± 2.5 µM).
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Two new triterpenoid saponins, named spermacosides A-B (1 - 2), together with two known oleanane-type triterpenoid saponins, 3-O-ß-D-xylopyranosyl-(1â3)-ß-D-glucopyranosylbayogenin (3) and 3-O-ß-D-glucopyranosylbayogenin (4), were isolated from the ethyl acetate extract of Spermacoce ocymoides Burm.f. in a phytochemical investigation. Their chemical structures were elucidated by spectroscopic data analysis (1D and 2D NMR, and HR-ESI-MS), as well as comparison with reported data. All these compounds were evaluated for inhibiting nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 cells. Among them, 1 showed a slight effect with an IC50 value of 108.65 ± 7.91 µM, and compounds 2-4 were inactive.
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3-Nitro-l-tyrosine (3NT) is an oxidative stress metabolite associated with neurodegenerative diseases such as Parkinson's disease and rheumatoid arthritis. In this study, the N, S-co-doped graphene quantum dots (NSGQDs) derived from nitrogen-doped Ti3C2Tx MXene nanosheet via the hydrothermal method in the presence of mercaptosuccinic acid was synthesized as an optical sensing probe to detect 3NT in human serum. Tetramethyl ammonium hydroxide, the nitrogen source and delamination agent, was used to prepare nitrogen-doped MXene nanosheets via one step at room temperature. The as-prepared NSGQDs are uniform with an average size of 1.2 ± 0.6 nm, and can be stable in aqueous solution for at least 90 d to serve as the fluorescence probe. The N atoms in N-MXene reduce the restacking and aggregation of MXene nanosheets, while the sulfur dopant in NSGQDs increases the quantum yield from 6.2 to 12.1 % as well as enhances the selectivity of 3NT over the other 12 interferences via coordination interaction with nitro group in 3NT. A linear range of 0.02-150 µM in PBS and 0.05-200 µM in human serum with a recovery of 97-108 % for 3NT detection is observed. Moreover, the limit of detection can be lowered to 4.2 and 7 nM in PBS and 1 × diluted human serum, respectively. Results obtained clearly indicate the potential application of the N-Ti3C2Tx derived NSGQD for effective detection of 3NT, which can open a window for the synthesis of doped GQDs via 2D MXene materials for ultrasensitive and selective detection of other biometabolites and biomarkers of neurodegenerative diseases in biological fluids.
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Grafite , Doenças Neurodegenerativas , Nitritos , Pontos Quânticos , Elementos de Transição , Tirosina/análogos & derivados , Humanos , NitrogênioRESUMO
Fructans are water-soluble polymers of fructose in which fructose units are linked by ß-(2 â 1) and/or ß-(2 â 6) linkages. In plants, they are synthesized in the vacuole but have also been reported in the apoplastic sap under abiotic stress suggesting that they are involved in plasmalemma protection and in plant-microbial interactions. However, the lack of fructan-specific antibodies currently prevents further study of their role and the associated mechanisms of action, which could be elucidated thanks to their immunolocalization. We report the production of two monoclonal antibodies (named BTM9H2 and BTM15A6) using mice immunization with antigenic compounds prepared from a mixture of plant inulins and levans conjugated to serum albumin. Their specificity towards fructans with ß-(2 â 1) and/or ß-(2 â 6) linkage has been demonstrated by immuno-dot blot tests on a wide range of carbohydrates. The two mAbs were used for immunocytolocalization of fructans by epifluorescence microscopy in various plant species. Fructan epitopes were specifically detected in fructan-accumulating plants, inside cells as well as on the surface of root tips, confirming both extracellular and intracellular localizations. The two mAbs provide new tools to identify the mechanism of extracellular fructan secretion and explore the roles of fructans in stress resistance and plant-microorganism interactions.
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Anticorpos Monoclonais , Frutanos , Animais , Camundongos , Plantas , Inulina , FrutoseRESUMO
The analysis of circulating tumor cells (CTCs) at the molecular level holds great promise for several clinical applications. For this goal, the harvest of high-purity, size-sorted CTCs with different subtypes from a blood sample are important. For this purpose, a two-step CTC isolation protocol was proposed, by which the immunomagnetic beads-based cell separation was first utilized to remove the majority of blood cells. After that, an optically induced dielectrophoresis (ODEP) microfluidic system was developed to (1) purify the CTCs from the remaining magnetic microbeads-bound blood cells and to (2) sort and separate the CTCs with different sizes. In this study, the ODEP microfluidic system was designed and fabricated. Moreover, its optimum operation conditions and performance were explored. The results exhibited that the presented technique was able to purify and sort the cancer cells with two different sizes from a tested cell suspension in a high-purity (93.5% and 90.1% for the OECM 1 and HA22T cancer cells, respectively) manner. Overall, this study presented a technique for the purification and sorting of cancer cells with different sizes. Apart from this application, the technique is also useful for other applications in which the high-purity and label-free purification and sorting of cells with different sizes is required.
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The current study aimed to identify the chemical constituents and bioactivities of the crude ethanolic extract (CEE) and its fractions (ethyl acetate (EAF), hexane (HEF), and aqueous (AEF)) from leaves of cashew (Anacardium occidentale L.) grown in Vietnam. A total of 31 compounds which belong to alkanes, hydrocarbons, iodine, terpenoids, phenolics, and flavonoids were determined by a gas chromatography-mass spectrometry (GC-MS) analysis, with bis(2-ethylhexyl) phthalate being the most prevailing compound. The highest total phenolic and flavonoid contents were obtained in the EAF, followed by HEF, CEE, and AQF. All samples showed promising in vitro antibacterial activity, enzyme inhibition, and anticancer activity. Among the samples tested, the EAF exhibited the highest enzyme inhibition activity against α-amylase and α-glucosidase (IC50 values of 51.24 µg/mL and 99.29 µg/mL, respectively), cytotoxicity activity against HeLa cells (IC50 value of 79.49 µg/mL), and antibacterial activity against Bacillus subtilis and Escherichia coli with MIC values of 5 mg/mL and 2.5 mg/mL, respectively. These findings suggest that the leaves of A. occidentale cultivated in Vietnam are a promising source of bioactive components and that EAF is a promising bioactive material warranting further pharmaceutical investigation.