RESUMO
The prevalence of Alzheimer's disease (AD) is increasing globally due to population aging. However, effective clinical treatment strategies for AD still remain elusive. The mechanisms underlying AD onset and the interplay between its pathological factors have so far been unclear. Evidence indicates that AD progression is ultimately driven by neuronal loss, which in turn is caused by neuroapoptosis and neuroinflammation. Therefore, the inhibition of neuroapoptosis and neuroinflammation could be a useful anti-AD strategy. Nonetheless, the delivery of active drug agents into the brain parenchyma is hindered by the blood-brain barrier (BBB). To address this challenge, we fabricated a black phosphorus nanosheet (BP)-based methylene blue (MB) delivery system (BP-MB) for AD therapy. After confirming the successful preparation of BP-MB, we proved that its BBB-crossing ability was enhanced under near-infrared light irradiation. In vitro pharmacodynamics analysis revealed that BP and MB could synergistically scavenge excessive reactive oxygen species (ROS) in okadaic acid (OA)-treated PC12 cells and lipopolysaccharide (LPS)-treated BV2 cells, thus efficiently reversing neuroapoptosis and neuroinflammation. To study in vivo pharmacodynamics, we established a mouse model of AD mice, and behavioral tests confirmed that BP-MB treatment could successfully improve cognitive function in these animals. Notably, the results of pathological evaluation were consistent with those of the in vitro assays. The findings demonstrated that BP-MB could scavenge excessive ROS and inhibit Tau hyperphosphorylation, thereby alleviating downstream neuroapoptosis and regulating the polarization of microglia from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype. Overall, this study highlights the therapeutic potential of a smart nanomedicine with the capability of reversing neuroapoptosis and neuroinflammation for AD treatment.
Assuntos
Doença de Alzheimer , Apoptose , Barreira Hematoencefálica , Azul de Metileno , Nanomedicina , Doenças Neuroinflamatórias , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Apoptose/efeitos dos fármacos , Células PC12 , Doenças Neuroinflamatórias/tratamento farmacológico , Ratos , Camundongos , Nanomedicina/métodos , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , Masculino , Espécies Reativas de Oxigênio/metabolismo , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: Potassium nitrate poisoning is a rare but potentially serious condition that can result in methemoglobinemia and subsequent cyanosis. This case report presents a unique instance of rapid-onset methemoglobinemia resulting from the ingestion of a traditional medicine preparation containing potassium nitrate, known as "kalmi shora." CASE PRESENTATION: A 14-year-old Pakistani boy reported to the emergency department with a history of sudden-onset headache, drowsiness agitation, irritability, and generalized cyanosis. Pulse oximetry showed a concerning oxygen saturation level of 58%, whereas arterial blood gas analysis revealed a normal partial pressure of oxygen (90 mmHg). The profile of abrupt onset of symptoms, generalized cyanosis, and the discrepancy between the partial pressure of oxygen and oxygen saturation readings necessitated a comprehensive assessment including inquiries into potential toxins. The peculiar appearance of the blood, resembling chocolate in color, further indicated the possibility of methemoglobinemia. The patient was successfully treated with methylene blue, leading to a prompt resolution of symptoms. CONCLUSION: This case highlights the significance of considering toxin exposures, such as traditional-medicine-induced poisoning, in emergency settings. The report contributes to the medical literature by highlighting the potential risks associated with traditional remedies and emphasizes the critical role of prompt diagnosis and intervention in optimizing patient outcomes. Recognition of the specific etiology of methemoglobinemia, in this case, traditional medicine ingestion, is essential for effective management in emergency medicine.
Assuntos
Metemoglobinemia , Azul de Metileno , Humanos , Azul de Metileno/uso terapêutico , Metemoglobinemia/induzido quimicamente , Metemoglobinemia/tratamento farmacológico , Masculino , Adolescente , Nitratos/intoxicação , Resultado do Tratamento , Cianose/induzido quimicamenteRESUMO
Two polyurethane polyaniline nanocomposites have been synthesized using two in situ polymerization routes of dried and wet bases to valorize the polyurethane waste. The physical and chemical properties of polyurethane-based nanocomposites were compared using SEM, XRD, FTIR, and Zeta potential. SEM images showed that the average particle size of the dried-based composite was 56 nm, while the wet-based composite had an average size of 75 nm. The separation efficiency for methylene blue (MB) and Congo red (CR) dyes was evaluated against free polyurethane foam waste. It was evident that pure polyurethane (PPU) achieved only 4.79% and 16.71% removal for MB and CR, respectively. These dye decontamination efficiencies were enhanced after nano polyaniline decoration of polyurethane foam either through dried base polymerization (DPUP) or wet base polymerization (WPUP). WPUP composite records 11.23% and 85.99% for MB and CR removal, respectively, improved to 26.69% and 90.07% removal using DPUP composite for the respective dyes. The adsorption kinetics, isotherms, and thermodynamics were investigated. The experimental results revealed the pseudo-second-order kinetic model as the most accurately described kinetics model for both CR and MB adsorption. The Langmuir model provided the best fit for the data, with maximum adsorption capacities of 110.98 mg/g for CR and 26.86 mg/g for MB, with corresponding R-squared values of 0.9974 and 0.9608, respectively. Regeneration and reusability studies of PPU, WPUP, and DPUP showed effective reusability, with DPUP displaying the highest adsorption capacity. These results aid in creating eco-friendly and cost-efficient adsorbents for dye removal in environmental sanitation.
Assuntos
Compostos de Anilina , Corantes , Nanocompostos , Poliuretanos , Poluentes Químicos da Água , Poliuretanos/química , Compostos de Anilina/química , Corantes/química , Poluentes Químicos da Água/química , Nanocompostos/química , Adsorção , Azul de Metileno/química , Eliminação de Resíduos Líquidos/métodos , Descontaminação/métodos , Cinética , Vermelho Congo/químicaRESUMO
Laser texturing seems to be a promising technique for reducing bacterial adhesion on titanium implant surfaces. This work aims to demonstrate the possibility of obtaining a functionally orientated surface of titanium implant elements with a specific architecture with specific bacteriological and photocatalytic properties. Femtosecond laser-generated surface structures, such as laser-induced periodic surface structures (LIPSS, wrinkles), grooves, and spikes on titanium, have been characterised by XRD, Raman spectroscopy, and scanning electron microscopy (SEM). The photocatalytic activity of the titanium surfaces produced was tested based on the degradation effect of methylene blue (MB). The correlation between the photocatalytic activity of TiO2 coatings and their morphology and structure has been analysed. Features related to the size, shape, and distribution of the roughness patterns were found to influence the adhesion of the bacterial strain on different surfaces. On the laser-structurised surface, the adhesion of Escherichia coli bacteria were reduced by 80% compared to an untreated reference surface.
Assuntos
Antibacterianos , Aderência Bacteriana , Escherichia coli , Lasers , Propriedades de Superfície , Titânio , Titânio/química , Titânio/farmacologia , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Aderência Bacteriana/efeitos dos fármacos , Catálise , Microscopia Eletrônica de Varredura , Humanos , Azul de Metileno/química , Azul de Metileno/farmacologia , Peri-Implantite/microbiologiaRESUMO
An in-situ nanozyme signal tag combined with a DNA-mediated universal antibody-oriented strategy was proposed to establish a high-performance immunosensing platform for Alzheimer's disease (AD)-related biomarker detection. Briefly, a Zr-based metal-organic framework (MOF) with peroxidase (POD)-like activity was synthesized to encapsulating the electroactive molecule methylene blue (MB), and subsequently modified with a layer of gold nanoparticles on its surface. This led to the creation of double POD-like activity nanozymes surrounding the MB molecule to form a nanozyme signal tag. A large number of hydroxyl radicals were generated by the nanozyme signal tag with the help of H2O2, which catalyzed MB molecules in situ to achieve efficient signal amplification. Subsequently, a DNA-aptamer-mediated universal antibody-oriented strategy was proposed to enhance the binding efficiency for the antigen (target). Meanwhile, a poly adenine was incorporated at the end of the aptamer, facilitating binding to the gold electrode and providing anti-fouling properties due to the hydrophilicity of the phosphate group. Under optimal conditions, this platform was successfully employed for highly sensitive detection of AD-associated tau protein and BACE1, achieving limits of detection with concentrations of 3.34 fg/mL and 1.67 fg/mL, respectively. It is worth mentioning that in the tau immunosensing mode, 20 clinical samples from volunteers of varying ages were analyzed, revealing significantly higher tau expression levels in the blood samples of elderly volunteers compared to young volunteers. This suggests that the developed strategy holds great promise for early AD diagnosis.
Assuntos
Doença de Alzheimer , Aptâmeros de Nucleotídeos , Biomarcadores , Técnicas Biossensoriais , Técnicas Eletroquímicas , Ouro , Nanopartículas Metálicas , Proteínas tau , Técnicas Biossensoriais/métodos , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/sangue , Técnicas Eletroquímicas/métodos , Ouro/química , Aptâmeros de Nucleotídeos/química , Biomarcadores/sangue , Nanopartículas Metálicas/química , Proteínas tau/sangue , Estruturas Metalorgânicas/química , Imunoensaio/métodos , Limite de Detecção , Secretases da Proteína Precursora do Amiloide , Azul de Metileno/química , Ácido Aspártico Endopeptidases/sangue , Peróxido de Hidrogênio/química , CatáliseRESUMO
This study investigates the potential of spent coffee ground biochar (SCGB) as a sustainable and cost-effective adsorbent for the removal of methylene blue (MB), a hazardous dye commonly used in the textile and printing industries. A response surface methodology (RSM) approach with central composite design (CCD) was employed to systematically investigate the effects of key process parameters, including adsorbent dosage, solution pH, contact time and temperature, on MB removal efficiency. The analysis revealed that adsorbent dosage and temperature as critical factors influencing MB removal, with a linear model providing a strong correlation. Optimal conditions for MB removal were determined to be 0.99 g of SCGB, 30 min of contact time, 30 °C temperature, and a solution pH of 7. Under these conditions, MB removal reached 99.99%, with a desirability of 1.000. The experimental results closely matched the predicted values, differing by only 0.02%, thus validating the accuracy of the model. Kinetic studies indicated a rapid adsorption process, well-described by both pseudo-first and pseudo-second order models. Isotherm analysis confirmed the applicability of the Freundlich model, suggesting favorable adsorption with increasing MB concentration. The high adsorption capacity of SCGB is attributed to its carbonaceous and porous structure, highlighting its potential as an effective adsorbent for dye removal in wastewater treatment applications.
Assuntos
Carvão Vegetal , Café , Azul de Metileno , Poluentes Químicos da Água , Azul de Metileno/química , Carvão Vegetal/química , Adsorção , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio , Café/química , Temperatura , Purificação da Água/métodos , Eliminação de Resíduos Líquidos/métodos , Corantes/química , Corantes/isolamento & purificaçãoRESUMO
MXene-based membranes, as a type of modified membrane, have unique structures that attract attention for water treatment but suffer from low water flux. To address this, MXene was manipulated with UiO-66-NH2 nanoparticles to create UiO-66-NH2@MXene 2D-nanocomposites for the modification of the PES membrane. Herein, we synthesized a novel modified MXene-based PES membrane. The MXene, UiO-66-NH2, and UiO-66-NH2@MXene were assessed using the Fourier transform infrared, X-ray diffraction pattern, X-ray photoelectron spectroscopy, and zeta potential analysis. Field emission scanning electron microscopy was used to evaluate the MXene-based materials and prepared membranes, and the surface topography of the fabricated membranes was studied using atomic force microscopy. The membrane modified by 0.25 wt% of modifier was able to not only remove 72% and 81% of methylene blue and crystal violet cationic dyes, but also recorded more than 91% rejections for methyl blue, methyl orange, acid fusion, and Congo red anionic dyes. Using the same membrane, salt rejections of 91%, 87%, 79%, and 62% were achieved for Na2SO4, MgSO4, MgCl2, and NaCl, respectively. Water flux was also increased by more than 4 times in the membrane modified with 0.25 wt% of the novel nanocomposite modifier, and the water contact angle of the membrane with 0.5 wt% decreased from 65° to 38° compared to the pristine PES membrane. Besides, the anti-fouling properties were exceptionally improved in the membranes modified by the introduced UiO-66-NH2@MXene nanocomposite modifier.
Assuntos
Membranas Artificiais , Nanocompostos , Purificação da Água , Nanocompostos/química , Purificação da Água/métodos , Poluentes Químicos da Água/química , Filtração/métodos , Estruturas Metalorgânicas/química , Corantes/química , Polímeros/química , Azul de Metileno/químicaRESUMO
BACKGROUND: Septic shock is now the leading cause of mortality in intensive care units (ICUs). Refractory septic shock requires high doses of vasopressors. Some previous studies have revealed that methylene blue could improve hypotension status and help reduce the dosage of catecholamines. This study aims to investigate the clinical effect of methylene blue in septic shock and explore whether it can increase arterial pressure and reduce the usage of vasopressors. METHODS: This study is a multicenter, randomized, placebo-controlled trial planning to include 100 refractory septic shock patients. The protocol is to administer a bolus of 2 mg/kg methylene blue intravenously followed by a continuous infusion of 0.5 mg/kg/h for 48 h. The primary outcome is the total dose of vasopressor required in refractory septic shock in the first 48 h. Secondary outcomes include other hemodynamic parameters, oxygen metabolism indexes, tissue perfusion indexes, major organ function indexes, and certain plasma cytokines and other factors. DISCUSSION: This protocol aims to evaluate the safety and efficacy of methylene blue as adjuvant therapy for refractory septic shock. The main outcome measure will be vasopressor requirements and hemodynamic parameters. Additionally, bedside ultrasonography, blood gases, and cytokines will be assessed to evaluate perfusion, respiratory, and metabolic effects. The results are intended to provide evidence on the safety and efficacy of methylene blue in refractory septic shock, guiding clinical decision-making. TRIAL REGISTRATION: This clinical trial has been registered at ChiCTR ( https://www.chictr.org.cn/ ) on March 16, 2023. ChiCTR registration number: ChiCTR2300069430.
Assuntos
Azul de Metileno , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Choque Séptico , Vasoconstritores , Choque Séptico/tratamento farmacológico , Azul de Metileno/uso terapêutico , Humanos , Vasoconstritores/uso terapêutico , Resultado do Tratamento , Hemodinâmica/efeitos dos fármacos , Pressão Arterial/efeitos dos fármacos , Unidades de Terapia Intensiva , AdultoRESUMO
A multifunctional polyoxometalate-ionic liquid (POM-IL)-based hybrid material comprising silicotungstic acid, [BmIm]4[SiW12O40], has been synthesized and demonstrated its efficiency toward methylene blue removal and as an antibacterial agent. Single-crystal XRD analysis confirms that the material crystallizes in monoclinic symmetry (SG: Pn), with lattice parameters a = 13.1396(5) Å, b = 16.9655(8) Å, c = 14.3493(7) Å, and Z = 2. The structure comprises a single polyanionic [SiW12O40]4- moiety surrounded by four cationic [BmIm]+ units of two different conformations, which supported DFT and Hirshfeld surface analysis. The material shows excellent removal efficiency for methylene blue, with a maximum adsorption capacity of 92.47 mg/g and 83.05% reusability after five cycles. On the contrary, FTIR and ζ-potential analyses confirm that electrostatic interactions are the predominant factors governing the adsorption process. The material also acts as a superior antibacterial agent against the opportunistic pathogens Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli with a MIC of 500-700 µg/mL. However, a comparative assessment showed that the material was more effective against P. aeruginosa compared to the other two pathogens. PXRD analysis confirms the phase purity, and FESEM and TEM analyses exhibit block-shaped morphology with particle sizes â¼2-3 µm.
Assuntos
Antibacterianos , Corantes , Líquidos Iônicos , Azul de Metileno , Compostos de Tungstênio , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Líquidos Iônicos/química , Líquidos Iônicos/farmacologia , Líquidos Iônicos/síntese química , Adsorção , Compostos de Tungstênio/química , Compostos de Tungstênio/farmacologia , Azul de Metileno/química , Azul de Metileno/farmacologia , Corantes/química , Corantes/farmacologia , Corantes/síntese química , Testes de Sensibilidade Microbiana , Escherichia coli/efeitos dos fármacos , Estrutura Molecular , Desenho de FármacosRESUMO
Near-infrared (NIR) organic materials have been widely developed for tumor phototherapy due to their deep tumor penetration, good biodegradability, and high photothermal conversion (PCE). However, most of the NIR organic dyes are easily destroyed by photooxidation due to their big and long conjugated structures, such as cyanine dyes. Under light irradiation, the reactive oxygen species (ROS) produced by these NIR dyes can easily break their conjugated skeleton, resulting in a dramatic decrease in phototherapeutic efficiency. Herein, an NIR organic dye cyanine dye (CyS) and a photosensitizer methylene blue (MB) were chosen to prepare nanocarrier CMTNPs by facile self-assembling with a natural antioxidant, tannic acid (TA). TA can greatly enhance the stability of NIR cyanine dyes by scavenging ROS. Furthermore, CMTNPs have a character of pH/thermal dual response, allowing for controlled release of MB in the slightly acidic tumor environment during photothermal therapy. The released MB can turn on both fluorescence and photodynamic therapy effects. In vitro and in vivo experiments demonstrated the remarkable tumor ablation ability of CMTNPs. Thus, our study provided an antiphotobleaching and controlled release photosensitizer strategy through the introduction of antioxidant TA into the nanocarrier for efficient collaborative photothermal/photodynamic therapy.
Assuntos
Raios Infravermelhos , Azul de Metileno , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Taninos , Taninos/química , Taninos/farmacologia , Animais , Camundongos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Humanos , Nanopartículas/química , Azul de Metileno/química , Azul de Metileno/farmacologia , Terapia Fototérmica , Portadores de Fármacos/química , Espécies Reativas de Oxigênio/metabolismo , Camundongos Endogâmicos BALB C , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Neoplasias/patologia , Linhagem Celular Tumoral , PolifenóisRESUMO
Familial Alzheimer's disease (FAD) is a chronic neurological condition that progresses over time. Currently, lacking a viable treatment, the use of multitarget medication combinations has generated interest as a potential FAD therapy approach. In this study, we examined the effects of 4-phenylbutyric acid (4-PBA) and methylene blue (MB) either separately or in combination on PSEN1 I416T cholinergic-like neuron cells (ChLNs), which serve as a model for FAD. We found that MB was significantly efficient at reducing the accumulation of intracellular Aß, phosphorylation of TAU Ser202/Thr205, and increasing Δψm, whereas 4-PBA was significantly efficient at diminishing oxidation of DJ-1Cys106-SH, expression of TP53, and increasing ACh-induced Ca2+ influx. Both agents were equally effective at blunting phosphorylated c-JUN at Ser63/Ser73 and activating caspase 3 (CASP3) into cleaved caspase 3 (CC3) on mutant cells. Combination of MB and 4-PBA at middle (0.1, 1) concentration significantly reduced iAß, p-TAU, and oxDJ-1 and augmented the ACh-induced Ca2+ influx compared to combined agents at low (0.05, 0.5) or high (0.5, 5) concentration. However, combined MB and 4-PBA were efficient only at dropping DJ-1Cys106-SO3 and increasing ACh-induced Ca2+ inward in mutant ChLNs. Our data show that the reagents MB and 4-PBA alone possess more than one action (e.g., antiamyloid, antioxidant, anti-TAU, antiapoptotic, and ACh-induced Ca2+ influx enhancers), that in combination might cancel or diminish each other. Together, these results strongly argue that MB and 4-PBA might protect PSEN1 I416T ChLNs from Aß-induced toxicity by working intracellularly as anti-Aß and anti-Tau agents, improving Δψm and cell survival, and extracellularly, by increasing ACh-induced Ca2+ ion influx. MB and 4-PBA are promising drugs with potential for repurposing in familial AD.
Assuntos
Doença de Alzheimer , Antioxidantes , Apoptose , Azul de Metileno , Fenilbutiratos , Presenilina-1 , Presenilina-1/genética , Presenilina-1/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/tratamento farmacológico , Azul de Metileno/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Humanos , Fenilbutiratos/farmacologia , Proteínas tau/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Peptídeos beta-Amiloides/metabolismo , Cálcio/metabolismo , Animais , Fosforilação/efeitos dos fármacosRESUMO
Prion diseases are 100% fatal infectious neurodegenerative diseases affecting the brains of humans and other mammals. The disease is caused by the formation and replication of prions, composed exclusively of the misfolded prion protein (PrPSc). We invented and developed the protein misfolding cyclic amplification (PMCA) technology for in vitro prion replication, which allow us to replicate the infectious agent and it is commonly used for ultra-sensitive prion detection in biological fluids, tissues and environmental samples. In this article, we studied whether PMCA can be used to screen for chemical compounds that block prion replication. A small set of compounds previously shown to have anti-prion activity in various systems, mostly using cells infected with murine prions, was evaluated for their ability to prevent the replication of prions. Studies were conducted simultaneously with prions derived from 4 species, including human, cattle, cervid and mouse. Our results show that only one of these compounds (methylene blue) was able to completely inhibit prion replication in all species. Estimation of the IC50 for methylene blue inhibition of human prions causing variant Creutzfeldt-Jakob disease (vCJD) was 7.7 µM. Finally, we showed that PMCA can be used for structure-activity relationship studies of anti-prion compounds. Interestingly, some of the less efficient prion inhibitors altered the replication of prions in some species and not others, suggesting that PMCA is useful for studying the differential selectivity of potential drugs.
Assuntos
Dobramento de Proteína , Animais , Humanos , Camundongos , Dobramento de Proteína/efeitos dos fármacos , Bovinos , Azul de Metileno/farmacologia , Azul de Metileno/química , Doenças Priônicas/tratamento farmacológico , Doenças Priônicas/metabolismo , Príons/metabolismo , Príons/química , Príons/antagonistas & inibidores , Proteínas PrPSc/metabolismo , Proteínas PrPSc/antagonistas & inibidores , Proteínas PrPSc/química , Avaliação Pré-Clínica de MedicamentosRESUMO
The rapid detection of contaminants in water resources is vital for safeguarding the environment, where the use of eco-friendly materials for water monitoring technologies has become increasingly prioritized. In this context, the role of biocomposites in the development of a SERS sensor is reported in this study. Grafted chitosan was employed as a matrix support for Ag nanoparticles (NPs) for the surface-enhanced Raman spectroscopy (SERS). Chitosan (CS) was decorated with thiol and carboxylic acid groups by incorporating S-acetyl mercaptosuccinic anhydride (SAMSA) to yield CS-SAMSA. Then, Ag NPs were immobilized onto the CS-SAMSA (Ag@CS-SAMSA) and characterized by spectral methods (IR, Raman, NIR, solid state 13C NMR with CP-MAS, XPS, and TEM). Ag@CS-SAMSA was evaluated as a substrate for SERS, where methylene blue (MB) was used as a model dye adsorbate. The Ag@CS-SAMSA sensor demonstrated a high sensitivity (with an enhancement factor ca. 108) and reusability over three cycles, with acceptable reproducibility and storage stability. The Raman imaging revealed a large SERS effect, whereas the MB detection varied from 1-100 µM. The limits of detection (LOD) and quantitation (LOQ) of the biocomposite sensor were characterized, revealing properties that rival current state-of-the-art systems. The dye adsorption profiles were studied via SERS by fitting the isotherm results with the Hill model to yield the ΔG°ads for the adsorption process. This research demonstrates a sustainable dual-function biocomposite with tailored adsorption and sensing properties suitable for potential utility in advanced water treatment technology and environmental monitoring applications.
Assuntos
Quitosana , Nanopartículas Metálicas , Prata , Análise Espectral Raman , Quitosana/química , Análise Espectral Raman/métodos , Prata/química , Nanopartículas Metálicas/química , Limite de Detecção , Corantes/química , Corantes/análise , Cátions/análise , Poluentes Químicos da Água/análise , Azul de Metileno/químicaRESUMO
AIM: The primary aim of this study was to validate the reliability, sensitivity and safety profile of novel combination of ICG- methylene blue dye as an SN tracer for PeCa. METHODS: This is a validation and non-randomised prospective observational study involving 25 patients (50 inguinal basins) who underwent SLNB where in ICG and methylene blue were used for localisation. The patients with clinically node negative groins were recruited in the study. SNs were identified intraoperatively using near infrared fluorescence imaging (NIRF Imaging system, SPY-PHI, Stryker, Sweden) and blue dye. The numbers of SNs identified by each tracer and the rates of complications and nodal recurrence during the followup. RESULTS: Overall 137 SNs were identified intraoperatively. Among the 137 SNs excised fluorescence, blue dye and Combined (blue + green) identified 57(41.6%), 27 (19.7%), and 51 (37.2%), respectively. The average number of SLNs removed per patient was 5 (range, 1-11) with sentinel lymph nodes detection rate at 94% (47/50). Seven patients had malignancy on SLNB and underwent ipsilateral radical inguinal lymphadenectomy. One patient had false negative SN and positive node in modified inguinal lymphadenectomy specimen. No adverse events were observed in all cases. CONCLUSION: The Novel combination of ICG fluorescence-Methylene blue dye technique is simple, reliable and safe. Moreover, it demonstrates a high SLN detection rate with a low false-negative rate, and it avoids radiation exposure.
Assuntos
Corantes , Verde de Indocianina , Canal Inguinal , Azul de Metileno , Neoplasias Penianas , Biópsia de Linfonodo Sentinela , Humanos , Masculino , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Penianas/patologia , Neoplasias Penianas/cirurgia , Neoplasias Penianas/diagnóstico por imagem , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Índia , AdultoRESUMO
A highly water-soluble and fluorescent N,S-doped carbon dots/europium (N,S-CDs/Eu) was successfully synthesized via a secondary hydrothermal method. This involved surface modification of N,S-CDs derived from sunflower stem pith (SSP) with europium ions (Eu3+) doping. When excited within the range of 400-470 nm, N,S-CDs/Eu exhibited a stable and broad optimal emission wavelength ranging from 505 to 540 nm. Notably, the photoluminescence quantum yield (PLQY) of N,S-CDs/Eu is 31.4%, significantly higher than the 19.5% observed for N,S-CDs. Additionally, by dissolving N,S-CDs/Eu into polyvinyl alcohol (PVA), a uniform fluorescent anti-counterfeiting ink can be prepared. The N,S-CDs/Eu/TiO2 composite demonstrates excellent photocatalytic degradation ability towards the organic dye methylene blue (MB). N,S-CDs/Eu has potential in the field of fluorescent inks and photocatalysis due to its simple and efficient preparation and excellent properties.
Assuntos
Carbono , Európio , Helianthus , Tinta , Pontos Quânticos , Európio/química , Carbono/química , Catálise , Pontos Quânticos/química , Helianthus/química , Processos Fotoquímicos , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Azul de Metileno/química , FluorescênciaRESUMO
Photodynamic therapy (PDT) is a promising alternative treatment for localized lesions and infections, utilizing reactive oxygen species (ROS) generated by photosensitizers (PS) upon light activation. Singlet oxygen (1O2) is a key ROS responsible for photodynamic damage. However, the effectiveness of PS in biological systems may not correlate with the efficiency of singlet oxygen generation in homogeneous solutions. This study investigated singlet oxygen generation and its decay in various cellular microenvironments using liposome and ARPE-19 cell models. Rose Bengal (RB), methylene blue (MB), and protoporphyrin IX (PpIX) were employed as selected PS. Lifetimes of singlet oxygen generated by the selected photosensitizers in different cellular compartments varied, indicating different quenching rates with singlet oxygen. RB, located near cell membranes, exhibited the highest phototoxicity and lipid/protein peroxidation, followed by PpIX, while MB showed minimal cytotoxicity in similar conditions. Singlet oxygen decay lifetimes provide insights into PS localization and potential phototoxicity, highlighting the importance of the lipid microenvironment in PDT efficacy, providing useful screening method prior to in vivo applications.
Assuntos
Lipossomos , Azul de Metileno , Fotoquimioterapia , Fármacos Fotossensibilizantes , Protoporfirinas , Rosa Bengala , Oxigênio Singlete , Oxigênio Singlete/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Humanos , Rosa Bengala/farmacologia , Rosa Bengala/química , Protoporfirinas/química , Protoporfirinas/farmacologia , Protoporfirinas/metabolismo , Lipossomos/química , Azul de Metileno/química , Azul de Metileno/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular , LuzRESUMO
Using biochar for dye wastewater treatment is attracting interest due to its excellent adsorption properties and low costs. In this work, a novel biochar derived from oxytetracycline fermentation residue (functionalized OFR biochar, FOBC) was investigated as a efficient adsorbent for typical dyes removal. At 25 °C, the maximum adsorption capacity calculated by Langmuir model of FOBC-3-600 for methylene blue (MB), malachite green (MG), and methyl orange (MO) reached 643.97, 617.89, and 521.03 mg/g, respectively. The kinetics and isotherm model fitting showed that the chemisorption and physisorption both occurred during the adsorption process. Dyes were efficiently adsorbed through pore filling, electrostatic attraction, π-π interactions, and surface complexation. And the cycling experiment and environmental risk assessment indicated that the FOBC-3-600 had excellent recyclability and utilization safety. Overall, this study provides a practical method to simultaneously treat the dyeing wastewater and utilize the antibiotic fermentation residue.
Assuntos
Antibacterianos , Carvão Vegetal , Corantes , Fermentação , Águas Residuárias , Poluentes Químicos da Água , Carvão Vegetal/química , Poluentes Químicos da Água/química , Adsorção , Corantes/química , Antibacterianos/química , Águas Residuárias/química , Azul de Metileno/química , Cinética , Porosidade , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Corantes de Rosanilina/química , Compostos Azo/química , Nitrogênio/químicaRESUMO
This study focuses on developing copper oxide-based nanocomposites using plant extracts for photocatalytic applications. Curcuma amada leaf and Alysicarpus vaginalis leaf extracts were utilized alongside recycled copper precursors to synthesize photocatalysts via a green synthesis approach. Structural characterization through X-ray diffraction confirmed the formation of monoclinic CuO with reduced crystallite sizes due to plant extract incorporation. Fourier-transform infrared spectroscopy identified additional functional groups from the plant extracts, enhancing the material's properties. UV-Vis spectroscopy demonstrated increased light absorption and narrowed bandgaps in the nanocomposites, crucial for efficient photocatalysis under visible light. Morphological studies using FESEM revealed unique leaf-like structures in nanocomposites, indicative of the plant extract's influence on morphology. Photocatalytic degradation of methylene blue, rhodamine B, Congo red, and reactive blue 171 dyes showed enhanced performance of plant extract-modified CuO compared to without plant extract mediated CuO, attributed to improved charge carrier separation and extended lifetime. The effects of pH, catalyst dosage, and dye concentration on degradation efficiency were systematically investigated, highlighting optimal conditions for each dye type. Radical scavenger studies confirmed the roles of holes and hydroxyl radicals in the degradation process. Kinetic analysis revealed pseudo-second-order kinetics for dye degradation, underscoring the effectiveness of the nanocomposites. Overall, this research provides insights into sustainable photocatalytic materials using plant extracts and recycled copper, showcasing their potential for environmental remediation applications.
Assuntos
Cobre , Nanocompostos , Extratos Vegetais , Nanocompostos/química , Cobre/química , Extratos Vegetais/química , Catálise , Azul de Metileno/químicaRESUMO
Currently, one of the primary challenges that human society must overcome is the task of decreasing the amount of energy used and the adverse effects that it has on the environment. The daily increase in liquid waste (comprising organic pollutants) is a direct result of the creation and expansion of new companies, causing significant environmental disruption. Water contamination is attributed to several industries such as textile, chemical, poultry, dairy, and pharmaceutical. In this study, we present the successful degradation of methylene blue dye using g-C3N4 (GCN) mixed with WO3 and V2O5 composites (GCN/WO3/V2O5 ternary composite) as a photocatalyst, prepared by a simple mechanochemistry method. The GCN/WO3/V2O5 ternary composite revealed a notable enhancement in photocatalytic performance, achieving around 97% degradation of aqueous methylene blue (MB). This performance surpasses that of the individual photocatalysts, namely pure GCN, GCN/WO3, and GCN/V2O5 composites. Furthermore, the GCN/WO3/V2O5 ternary composite exhibited exceptional stability even after undergoing five consecutive cycles. The exceptional photocatalytic activity of the GCN/WO3/V2O5 ternary composite can be ascribed to the synergistic effect of metal-free GCN and metal oxides, resulting in the alteration of the band gap and suppression of charge recombination in the ternary photocatalyst. This study offers a better platform for understanding the characteristics of materials and their photocatalytic performance under visible light conditions.
Assuntos
Azul de Metileno , Óxidos , Tungstênio , Poluentes Químicos da Água , Tungstênio/química , Óxidos/química , Catálise , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Azul de Metileno/química , Grafite/química , Purificação da Água/métodos , Processos Fotoquímicos , Fotólise , Compostos de NitrogênioRESUMO
Carbon quantum dots (CQDs) were successfully synthesized from carbohydrate-rich residue of birch obtained following the lignin-first strategy. The optical and physicochemical properties of the CQDs were studied, along with their potential for photocatalytic pollutant degradation. By combining solvothermal and chemical oxidation methods, the product yield of CQDs from carbohydrate-rich residue reached 8.1 wt%. Doping nitrogen enhances the graphitization of CQDs and introduces abundant amino groups to the surface, thereby boosted the quantum yield significantly from 8.9 % to 18.7 %-19.3 %. Nitrogen-doped CQDs exhibited efficient photocatalytic degradation of methylene blue, reaching 37 % within 60 min, with a kinetic degradation rate of 0.00725 min-1. This study demonstrates that carbohydrate-rich residue obtained from lignin-first strategy are ideal precursors for synthesizing CQD with high mass yield and quantum yield by combining solvothermal treatment and chemical oxidation methods, offering a novel approach for the utilization of whole biomass components following the lignin-first strategy.