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1.
Phys Med ; 124: 103422, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38981169

RESUMEN

PURPOSE: Interdisciplinary scientific communities have shown large interest to achieve a mechanistic description of radiation-induced biological damage, aiming to predict biological results produced by different radiation quality exposures. Monte Carlo track-structure simulations are suitable and reliable for the study of early DNA damage induction used as input for assessing DNA damage. This study presents the most recent improvements of a Geant4-DNA simulation tool named "dsbandrepair". METHODS: "dsbandrepair" is a Monte Carlo simulation tool based on a previous code (FullSim) that estimates the induction of early DNA single-strand breaks (SSBs) and double-strand breaks (DSBs). It uses DNA geometries generated by the DNAFabric computational tool for simulating the induction of early single-strand breaks (SSBs) and double-strand breaks (DSBs). Moreover, the new tool includes some published radiobiological models for survival fraction and un-rejoined DSB. Its application for a human fibroblast cell and human umbilical vein endothelial cell containing both heterochromatin and euchromatin was conducted. In addition, this new version offers the possibility of using the new IRT-syn method for computing the chemical stage. RESULTS: The direct and indirect strand breaks, SSBs, DSBs, and damage complexity obtained in this work are equivalent to those obtained with the previously published simulation tool when using the same configuration in the physical and chemical stages. Simulation results on survival fraction and un-rejoined DSB are in reasonable agreement with experimental data. CONCLUSIONS: "dsbandrepair" is a tool for simulating DNA damage and repair, benchmarked against experimental data. It has been released as an advanced example in Geant4.11.2.

2.
Heliyon ; 10(11): e31950, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38882347

RESUMEN

Background: Lung cancer is the second most diagnosed cancer and the leading cause of cancer death in 2020, representing approximately one in 10 (11.4 %) cancers diagnosed and one in 5 (18.0 %) deaths. There are currently very few studies evaluating the prevalence and related factors of lung cancer detected using low-dose CT scans. Objective: Evaluate the prevalence and related factors of lung cancer using low-dose CT scans in high-risk populations in Vietnam. Materials and methods: A cross-sectional analysis study of 169 high-risk patients was conducted to assess the lung cancer prevalence and related factors. Enrolled patients received a physical examination, low-dose computerized tomography scan, and biopsy if abnormalities were found through the CT scan. Univariable and Multivariable analysis through Odd Ratio (OR) to assess the related risk of lung cancer. Results: A total of 169 high-risk patients with a mean age of 62.93 ± 9.31 (years), and the majority were male (91.7 %). Of which 4 cases (2.37 %) were recorded with lung cancer, 3 cases of adenocarcinoma, and 1 case of squamous cell carcinoma. A history of smoking and Chronic Obstructive Pulmonary Disease (COPD) were associated with an increased risk of abnormalities on lung CT scans. Multivariate regression analysis revealed that smoking over 30 pack-years and COPD significantly increased the risk of abnormalities on lung CT scans, p < 0.05.100 % of lung cancer-detected cases were male and smoking ≥30 pack - years. Conclusion: The prevalence of lung cancer in the Vietnamese high-risk population was relatively high. Relative factors such as smoking ≥30 pack - years, and COPD had increased risk of CTscan abnormalities.

3.
J Nucl Med ; 65(7): 1043-1050, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38782457

RESUMEN

The incidence of androgen receptor (AR)-negative (AR-) prostate cancer, including aggressive neuroendocrine prostate cancer (NEPC), has more than doubled in the last decade, but its timely diagnosis is difficult as it lacks typical prostate cancer hallmarks. The carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) has recently been identified as an upregulated surface antigen in NEPC. We developed an immuno-PET agent targeting CEACAM5 and evaluated its ability to delineate AR- prostate cancer in vivo. Methods: CEACAM5 expression was evaluated in a panel of prostate cancer cell lines by immunohistochemistry and Western blotting. The CEACAM5-targeting antibody labetuzumab was conjugated with the chelator desferrioxamine (DFO) and radiolabeled with 89Zr. The in vivo distribution of the radiolabeled antibody was evaluated in xenograft prostate cancer models by PET imaging and ex vivo organ distribution. Results: The NEPC cell line H660 exhibited strong CEACAM5 expression, whereas expression was limited in the AR- cell lines PC3 and DU145 and absent in the AR-positive cell line LNCaP. [89Zr]Zr-DFO-labetuzumab imaging was able to clearly delineate both neuroendocrine H660 xenografts and AR- DU145 in vivo but could not detect the AR-positive xenograft LNCaP. Conclusion: Immuno-PET imaging with [89Zr]Zr-DFO-labetuzumab is a promising diagnostic tool for AR- prostate cancer.


Asunto(s)
Proteínas Ligadas a GPI , Tomografía de Emisión de Positrones , Neoplasias de la Próstata , Receptores Androgénicos , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Línea Celular Tumoral , Animales , Ratones , Receptores Androgénicos/metabolismo , Proteínas Ligadas a GPI/metabolismo , Antígenos CD/metabolismo , Circonio , Distribución Tisular , Moléculas de Adhesión Celular/metabolismo , Radioisótopos , Antígeno Carcinoembrionario
4.
Chemosphere ; 355: 141748, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38521109

RESUMEN

Sugarcane bagasse is one of the most common Vietnamese agricultural waste, which possesses a large percentage of cellulose, making it an abundant and environmentally friendly source for the fabrication of cellulose carbon aerogel. Herein, waste sugarcane bagasse was used to synthesize cellulose aerogel using different crosslinking agents such as urea, polyvinyl alcohol (PVA) and sodium alginate (SA). The 3D porous network of cellulose aerogels was constructed by intermolecular hydrogen bonding, which was confirmed by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen adsorption/desorption. Among the three cellulose aerogel samples, cellulose - SA aerogel (SB-CA-SA) has low density of 0.04 g m-3 and high porosity of 97.38%, leading to high surface area of 497.9 m2 g-1 with 55.67% micropores of activated carbon aerogel (SB-ACCA-SA). The salt adsorption capacity was high (17.87 mg g-1), which can be further enhanced to 31.40 mg g-1 with the addition of CNT. Moreover, the desalination process using the SB-ACCA-SA-CNT electrode was stable even after 50 cycles. The results show the great combination of cellulose from waste sugarcane bagasse with sodium alginate and carbon nanotubes in the fabrication of carbon materials as the CDI-utilized electrodes with high desalination capability and good durability.


Asunto(s)
Nanotubos de Carbono , Saccharum , Celulosa/química , Saccharum/química , Alginatos
5.
Biomed Mater ; 19(3)2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38537280

RESUMEN

The biomaterials based on chitosan andEclipta prostrataL. extract have been prepared by microemulsion method and solution method (with and without sodium tripolyphosphate (STPP) as a cross-linking agent). The main component inEclipta prostrataL. extract is flavonoid groups. The structure of the chitosan/extract biomaterials was studied by infrared spectroscopy. The chitosan/extract biomaterial using STPP cross-linker appeared an absorption band at 1152 cm-1attributed to the vibrations of C-O-P bonds, which proved that chitosan has crosslinked with STPP. The morphology of the biomaterials was investigated by the dynamic light scattering technique and field emission scanning electron microscopy. The obtained results showed that the particle size of the chitosan/extract biomaterials prepared by microemulsion method and solution method with STPP ranged from 68.06 nm to 1484 nm, with an average particle size of 304.9-1019 nm. The microemulsion method produced biomaterials with much smaller average particle size than the solution method using cross-linkers. The hemostatic ability of the biomaterials was better than that of the control sample based on the time of blood clotting formation and glomerular aggregation ability. The sample with the ratio ofE. prostrataL. extract: chitosan of 1:30 had the lowest hemostasis time (6 min 46 s) and its glomerular aggregation rate after 5 min was 13.05%. This indicated that the biomaterials based on chitosan andE. prostrataL. extract are promising for application in biomedicine as hemostatic materials.


Asunto(s)
Quitosano , Hemostáticos , Quitosano/química , Materiales Biocompatibles/química , Hemostasis , Coagulación Sanguínea
6.
Clin Case Rep ; 12(4): e8726, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38550741

RESUMEN

An epidermoid cyst is a benign tumor in many locations. The symptoms of an epidermoid cyst depend on its location. The brain or spine MRI can confirm the lesion. Removing total decompression is the first choice in treatment with a symptomatic cyst.

7.
HIV Med ; 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443319

RESUMEN

INTRODUCTION: Co-infection with HIV and mpox is a significant issue for public health because of the potential combined impact on clinical outcomes. However, the existing literature lacks a comprehensive synthesis of the available evidence. The purpose of this meta-analysis is to provide insight into the impact of HIV and mpox co-infection on clinical outcomes. METHODS: We systematically searched major electronic databases (PubMed, Embase, Cochrane Central, and Web of Science) for pertinent studies published up to June 2023. Included were studies that described the clinical outcomes of people who had both mpox and HIV. We performed the analysis using OpenMeta and STATA 17 software. RESULTS: With an overall number of participants of 35 207, 21 studies that met the inclusion criteria were considered. The greatest number of the studies (n = 10) were cohort designs, with three being cross-sectional and eight being case series studies. The meta-analysis found that people who had both HIV and mpox had a higher hospitalization rate than those who only had mpox (odds ratio [OR] 1.848; 95% confidence interval [CI] 0.918-3.719, p = 0.085, I2 = 60.19%, p = 0.020). Furthermore, co-infected patients had higher mortality rates than those who did not have HIV co-infection (OR 3.887; 95% CI 2.272-6.650, p < 0.001). Meta-regression analysis showed that CD4 levels can significantly predict the risk of hospitalization (p = 0.016) and death (p = 0.031). DISCUSSION: HIV causes immunosuppression, making it difficult for the body to mount an effective immune response against pathogens such as mpox. Individuals who are co-infected are at a higher risk of severe disease and death, according to our findings. Although hospitalization rates did not differ significantly between the two groups, it is critical to prioritize interventions and improve management strategies tailored specifically for people living with HIV. CONCLUSION: This meta-analysis provides substantial evidence that HIV and mpox co-infection has a negative impact on clinical outcomes. Co-infected individuals had higher hospitalization and significantly higher mortality rates. These findings highlight the significance of early diagnosis, prompt treatment initiation, and effective management strategies for people living with HIV and mpox.

8.
Acta Psychol (Amst) ; 241: 104096, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38041914

RESUMEN

Managers have been applying the influence of herd behaviour to stimulate purchase intention but have not achieved precise results because they do not clearly understand the mechanism of this relationship. This article aims to determine the effect of herd behaviour on the relationship between information adoption and purchase intention and the moderating of risk aversion. With 17 variables for four concepts, data was collected online with 340 respondents and analysed with a partial least squares structural equation modelling. When considering herd behaviour in terms of subjective norms with corroborated information, this study upgrades the classic role of the theory of planned behaviour in purchase intention. The findings indicate a positive relationship between herd behaviour, information adoption and purchase intention. In particular, risk aversion is a positive moderator of the relationship between herd behaviour and purchase intention. This result is a significant addition to the theoretical body and shows that risk aversion can drive purchase intention through herd behaviour. In other words, this study upgrades the perception of information source authentication through herd behaviour to explain the purchase intentions of Vietnamese consumers. These results show that managers can create risky situations to promote herd behaviour. They can also apply information adoption stimuli to stimulate herd behaviour. At the same time, through the information adoption mechanism, consumers can be more alert to the effect of herd behaviour and have more opinions when making purchases.


Asunto(s)
Actitud , Intención , Humanos , Vietnam , Comportamiento del Consumidor
9.
Inorg Chem ; 62(48): 19677-19689, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-37977192

RESUMEN

We report the synthesis and comprehensive characterization of organic-inorganic hybrid salts formed by bis-cationic N,N'-bis(2-(trimethylammonium)ethylene)perylene-3,4,9,10-tetracarboxylic acid bisimide (PTCD2+) and Keggin-type [XW12O40]n- (X = Si, n = 4; X = P, n = 3) polyoxometalates. (PTCD)3[PW12O40]2·3DMSO·2H2O (2) and (PTCD)2[SiW12O40]·DMSO·2H2O (3) were structurally characterized by single crystal X-ray diffraction. The cations in both structures exhibited infinite chainlike arrangements through π-π interactions, contrasting with the previously reported cation-anion stacking observed in naphthalene diimide derivatives. A detailed theoretical study employing topological analysis of the electron density distribution within the quantum theory of atoms in molecules approach provided further insights into this structural dualism. Atomic force microscopy analyses revealed the formation of self-assembled supramolecular structures on graphite from molecular monolayers (3 nm of thick) to submicrometer aggregates for 2. Hyperspectral Raman spectroscopy imaging revealed that such heterostructures are likely formed by an enhanced π-π interactions. Both complexes demonstrated interesting electrochemical behavior, photoluminescence and X-ray-induced luminescence. Electron spin resonance analysis confirmed charge separation in both compounds, with enhanced efficiency observed in compound 2. Our findings of these perylene-based organic-inorganic hybrid salts offer the potential for their application in optoelectronic devices and functional materials.

10.
Bioconjug Chem ; 34(11): 1925-1950, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37737084

RESUMEN

The term "click chemistry" describes a class of organic transformations that were developed to make chemical synthesis simpler and easier, in essence allowing chemists to combine molecular subunits as if they were puzzle pieces. Over the last 25 years, the click chemistry toolbox has swelled from the canonical copper-catalyzed azide-alkyne cycloaddition to encompass an array of ligations, including bioorthogonal variants, such as the strain-promoted azide-alkyne cycloaddition and the inverse electron-demand Diels-Alder reaction. Without question, the rise of click chemistry has impacted all areas of chemical and biological science. Yet the unique traits of radiopharmaceutical chemistry have made it particularly fertile ground for this technology. In this update, we seek to provide a comprehensive guide to recent developments at the intersection of click chemistry and radiopharmaceutical chemistry and to illuminate several exciting trends in the field, including the use of emergent click transformations in radiosynthesis, the clinical translation of novel probes synthesized using click chemistry, and the advent of click-based in vivo pretargeting.


Asunto(s)
Azidas , Química Clic , Radioquímica , Azidas/química , Radiofármacos/química , Reacción de Cicloadición , Alquinos/química
11.
Int J Inf Technol ; : 1-9, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37360317

RESUMEN

Overcrowding in hospitals in Vietnam has caused many disadvantages in receiving and treating patients. Especially at the stage of receiving and diagnosing procedures taking patients to the treatment departments in the hospital takes up much time. This study proposes a text-based disease diagnosis using text processing techniques (such as Bag of Words, Term Frequency- Inverse Document Frequency, and Tokenizer) combined with classifiers (such as Random Forests (RF), Multi-Layer Perceptron (MLP), Embeddings and Bidirectional Long Short-term memory (LSTM)) on symptoms. As observed from the results, deep Bidirectional LSTM can reach 0.982 in AUC in the classification of 10 diseases on 230,457 samples of pre-diagnosis collected from Vietnam hospitals used in the training and testing phases. The proposed approach is expected to provide a way to automate patient flow in hospitals to improve healthcare in the future.

12.
Antibiotics (Basel) ; 12(6)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37370273

RESUMEN

Linezolid is an antibiotic of last resort for the treatment of infections caused by Gram-positive bacteria, including vancomycin-resistant enterococci. Enterococcus faecalis, a member of enterococci, is a significant pathogen in nosocomial infections. E. faecalis resistance to linezolid is frequently related to the presence of optrA, which is often co-carried with fex, phenicol exporter genes, and erm genes encoding macrolide resistance. Therefore, the common use of antibiotics in veterinary might promote the occurrence of optrA in livestock settings. This is a cross-sectional study aiming to investigate the prevalence of optrA positive E. faecalis (OPEfs) in 6 reservoirs in farms in Ha Nam province, Vietnam, and its associated factors and to explore genetic relationships of OPEfs isolates. Among 639 collected samples, the prevalence of OPEfs was highest in flies, 46.8% (51/109), followed by chickens 37.3% (72/193), dogs 33.3% (17/51), humans 18.7% (26/139), wastewater 16.4% (11/67) and pigs 11.3%, (14/80). The total feeding area and total livestock unit of the farm were associated with the presence of OPEfs in chickens, flies, and wastewater. Among 186 OPEfs strains, 86% were resistant to linezolid. The presence of optrA was also related to the resistant phenotype against linezolid and levofloxacin of E. faecalis isolates. Close genotypic relationships identified by Pulsed Field Gel Electrophoresis between OPEfs isolates recovered from flies and other reservoirs including chickens, pigs, dogs, and wastewater suggested the role of flies in the transmission of antibiotic-resistant pathogens. These results provided warnings of linezolid resistance although it is not used in livestock.

13.
Aesthet Surg J ; 43(11): 1376-1383, 2023 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-37186025

RESUMEN

BACKGROUND: Data breach costs in the United States are among the highest in the world, making robust cybersecurity an important bulwark of national defense. Healthcare is a popular target for cyber threats, and there is increasing emphasis on cybersecurity safeguards to protect sensitive patient data. OBJECTIVES: The objective of this national survey and scoping review is to (1) identify cybersecurity awareness, preparedness, and practices among plastic surgeons, and (2) to provide guidelines to mitigate the threat of cyberattacks. METHODS: A 16-question, anonymous online survey was developed and distributed to The Aesthetic Society registrants to ascertain plastic surgeons' cybersecurity practices. Utilizing PubMed, CINAHL, and Embase databases, eligible articles were identified as part of this scoping review. RESULTS: Of 89 individuals who began the survey, 69 completed it (77.5%). Sixty respondents agreed or strongly agreed that cybersecurity is an important issue in plastic surgery. The greatest perceived limitations for protection against cyberattacks were insufficient expertise (41.7%), followed by lack of funding and insufficient time to dedicate to this goal. Most respondents (78.7%) had cybersecurity policies incorporated into their practice. Those who agreed or strongly agreed they had technology to prevent data theft/breach were significantly more likely to be older than 54 years of age (P < .001). No articles identified in the literature specifically addressed cybersecurity in plastic surgery; however, 12 articles detailing cybersecurity in healthcare were identified and included. CONCLUSIONS: Despite possessing adequate technology and procedures in place to prevent cyberattacks, plastic surgeons perceive significant barriers to cybersecurity protection, including insufficient expertise and lack of dedicated funding. It is imperative that our field establishes standards and protocols to protect our patients.


Asunto(s)
Procedimientos de Cirugía Plástica , Cirujanos , Cirugía Plástica , Humanos , Estados Unidos , Encuestas y Cuestionarios , Seguridad Computacional
14.
Analyst ; 148(9): 1912-1929, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-36928639

RESUMEN

Microfluidic cytometry (MC) and electrical impedance spectroscopy (EIS) are two important techniques in biomedical engineering. Microfluidic cytometry has been utilized in various fields such as stem cell differentiation and cancer metastasis studies, and provides a simple, label-free, real-time method for characterizing and monitoring cellular fates. The impedance microdevice, including impedance flow cytometry (IFC) and electrical impedance spectroscopy (EIS), is integrated into MC systems. IFC measures the impedance of individual cells as they flow through a microfluidic device, while EIS measures impedance changes during binding events on electrode regions. There have been significant efforts to improve and optimize these devices for both basic research and clinical applications, based on the concepts, electrode configurations, and cell fates. This review outlines the theoretical concepts, electrode engineering, and data analytics of these devices, and highlights future directions for development.


Asunto(s)
Técnicas Analíticas Microfluídicas , Microfluídica , Ciencia de los Datos , Electrodos , Diferenciación Celular , Impedancia Eléctrica , Espectroscopía Dieléctrica/métodos , Técnicas Analíticas Microfluídicas/métodos
15.
Lancet Reg Health West Pac ; 30: 100668, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36748068

RESUMEN

Background: Drug outlets are a vital first point of healthcare contact in low- and middle-income countries (LMICs), but they are often poorly regulated and counter staff may be unqualified to provide advice. This introduces the risk of easy access to potentially harmful products, including unnecessary antimicrobials. Over-the-counter antimicrobial sales are a major driver of antimicrobial resistance (AMR) in LMICs. We aimed to investigate the distribution of different types of drug outlets and their association with socio-economic factors. Methods: We mapped the location of drug outlets in 40 randomly selected geographic clusters, covering a population of 1.96 million people. Data including type of drug outlet, context, operating hours, chief pharmacist name and qualification, and business registration identification were collected from mandatory public signage. We describe the density of drug outlets and levels of staff qualifications in relation to population density, urban vs rural areas, and poverty indices. Findings: We characterised 1972 drug outlets. In the study area, there was an average of 102 outlets/per 100,000 population, compared to the global average of 25. Predictably, population density was correlated with the density of drug outlets. We found that drug outlets were less accessible in rural vs urban areas, and for the poor. Furthermore, for these populations, degree-qualified pharmacists were less accessible and public signage frequently lacked mandatory registration information. Interpretation: Drug outlets appear over-supplied in Vietnam compared to other countries. Unregistered outlets and outlets without degree-qualified pharmacists are prevalent, especially in poor and rural areas, posing a risk for inappropriate supply of antimicrobials, which may contribute to AMR, and raises questions of equitable healthcare access. Funding: This study was funded by a grant from the Australian Department of Foreign Affairs and Trade.

16.
Sci Rep ; 12(1): 20189, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36424459

RESUMEN

The human gut microbiota has been shown to be significantly perturbed by antibiotic use, while recovering to the pre-treatment state several weeks after short antibiotic exposure. The effects of antibiotics on the gut microbiota have however been mainly documented in high-income settings with lower levels of antibiotic resistance as compared to lower and middle income countries (LMIC). This study aimed to examine the long-term consequences of repeated exposure to commonly use antibiotics on the fecal microbiota of residents living in a low income setting with high prevalence of antibiotic resistance. Fecal samples from household individuals (n = 63) participating in a rural cohort in northern Vietnam were collected monthly for a period of 6 months. Using 16S V4 rRNA gene region amplicon sequencing and linear mixed-effects models analysis, we observed only a minor and transient effect of antibiotics on the microbial richness (ß = - 31.3, 95%CI = - 55.3, - 7.3, p = 0.011), while the microbial diversity was even less affected (ß = - 0.298, 95%CI - 0.686, 0.090, p = 0.132). Principal Component Analyses (PCA) did not reveal separation of samples into distinct microbiota-based clusters by antibiotics use, suggesting the microbiota composition was not affected by the antibiotics commonly used in this population. Additionally, the fecal microbial diversity of the subjects in our study cohort was lower when compared to that of healthy Dutch adults (median 3.95 (IQR 3.72-4.13) vs median 3.69 (IQR3.31-4.11), p = 0.028, despite the higher dietary fiber content in the Vietnamese as compared to western diet. Our findings support the hypothesis that frequent antibiotic exposure may push the microbiota to a different steady state that is less diverse but more resilient to disruption by subsequent antibiotic use.


Asunto(s)
Microbioma Gastrointestinal , Adulto , Humanos , Microbioma Gastrointestinal/genética , Antibacterianos/efectos adversos , Vietnam , Estudios de Cohortes , Pueblo Asiatico
17.
RSC Adv ; 12(51): 33403-33408, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36425159

RESUMEN

In this work, a method of fabricating a NO2 nano-sensor working at room temperature with a low detectable concentration limit is proposed. A 2D-MoS2 flake is isolated by transferring a single MoS2 flake to SiO2/Si substrate, followed by applying an advanced e-beam lithography (EBL) to form a metal contact with Au/Cr electrodes. The resulting chemoresistive nano-sensor using a single MoS2 flake was applied to detect a very low concentration of NO2 at the part-per-billion (ppb) level. This result is obtained due to the ability to create microscopic nano-sized MoS2 gaps using e-beam lithography (300 nm-400 nm). Experimental results also show that the sensor can capture changes in concentration and send the information out extremely quickly. The response and recovery time of the sensor also reached the lowest point of 50 and 75 ms, outperforming other sensors with a similar concentration working range.

18.
Environ Sci Technol ; 56(15): 10829-10837, 2022 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-35767386

RESUMEN

Given the widespread use of TiO2, its release into aquatic systems and complexation with dissolved organic matter (DOM) are highly possible, making it important to understand how such interactions affect photocatalytic activity under visible light. Here, we show that humic acid/TiO2 complexes (HA/TiO2) exhibit photoactivity (without significant electron-hole activation) under visible light through ligand-to-metal charge transfer (LMCT). The observed visible-light activities for pollutant removal and bacterial inactivation are primarily linked to the generation of H2O2via the conduction band. By systematically considering molecular-scale interactions between TiO2 and organic functional groups in HA, we find a key role of phenolic groups in visible-light absorption and H2O2 photogeneration. The photochemical formation of H2O2 in river waters spiked with TiO2 is notably elevated above naturally occurring H2O2 generated from background organic constituents due to LMCT contribution. Our findings suggest that H2O2 generation by HA/TiO2 is related to the quantity and functional group chemistry of DOM, which provides chemical insights into photocatalytic activity and potential ecotoxicity of TiO2 in environmental and engineered systems.


Asunto(s)
Materia Orgánica Disuelta , Procesos Fotoquímicos , Peróxido de Hidrógeno , Ligandos , Luz , Titanio/química
19.
ChemSusChem ; 15(13): e202200220, 2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35307983

RESUMEN

The conversion of biomass into a great variety of valuable chemicals, polymers, and fuels gives a sustainable alternative for the insufficiency of non-renewable fossil fuel resources and reduces environmental pollution. 5-Hydroxymethylfurfural (HMF), converted from sustainable carbohydrates, is a significant building block chemical, and the selective oxidation of HMF into 2,5-diformylfuran (DFF) presents an ongoing challenge. DFF is a versatile platform molecule derived from biomass and has promising application in pharmaceuticals and polymers. This Review provides an overview of the latest developments of efficient catalytic systems for the sustainable conversion of HMF to DFF.


Asunto(s)
Furaldehído , Polímeros , Biomasa , Furaldehído/análogos & derivados , Furaldehído/química , Furanos
20.
Mol Imaging Biol ; 24(4): 511-518, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35147837

RESUMEN

PURPOSE: Immuno-positron emission tomography (immunoPET) combines the specificity of an antibody with the sensitivity of PET to image dysregulated pathways in cancer. This study examines the performance of immunoPET using the radioimmunoconjugate [89Zr]Zr-DFO-Panitumumab to detect epidermal growth factor receptor (EGFR) expression in an orthotopic model of bladder cancer (BCa). PROCEDURES: Expression and quantification of EGFR receptors were confirmed in four different BCa cell lines. Binding assays validated [89Zr]Zr-DFO-Panitumumab specificity for EGFR-expressing UMUC3 BCa cells. Subcutaneous and orthotopic UMUC3 xenografts were then used for PET imaging and ex vivo biodistribution of the radioimmunoconjugate. Control cohorts included non-tumor mice, 89Zr-labeled non-specific IgG, and blocking experiments. RESULTS: [89Zr]Zr-DFO-Panitumumab binds specifically to EGFR-expressing UMUC3 cells with a Bmax value of 5.9 × 104 EGFRs/cell in vitro. ImmunoPET/CT images show localization of the antibody in subcutaneous UMUC3 xenografts and murine bladder tumors. In the orthotopic model, the immunoPET signal correlates with the respective tumor volume. Ex vivo biodistribution analysis further confirmed imaging results. CONCLUSION: The preclinical data presents a proof of concept for utilizing EGFR-targeted immunoPET to image BCa with altered EGFR protein levels.


Asunto(s)
Inmunoconjugados , Neoplasias de la Vejiga Urinaria , Animales , Línea Celular Tumoral , Receptores ErbB/metabolismo , Humanos , Ratones , Panitumumab , Tomografía de Emisión de Positrones/métodos , Distribución Tisular , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Circonio
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