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1.
Open Vet J ; 14(1): 416-427, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38633182

RESUMO

Background: Acute lung injury (ALI) is a severe condition distinguished by inflammation and impaired gas exchange in the lungs. Staphylococcus aureus, a common bacterium, can cause ALI through its virulence factors. Aloe vera is a medicinal plant that has been traditionally used to treat a variety of illnesses due to its anti-inflammatory properties. Chitosan nanoparticles are biocompatible and totally biodegradable materials that have shown potential in drug delivery systems. Aim: To explore the antibacterial activity of Aloe vera-loaded chitosan nanoparticles (AV-CS-NPs) against S. aureus in vitro and in vivo with advanced techniques. Methods: The antibacterial efficacy of AV-CS-NPs was evaluated through a broth microdilution assay. In addition, the impact of AV-CS-NPs on S. aureus-induced ALI in rats was examined by analyzing the expression of genes linked to inflammation, oxidative stress, and apoptosis. Furthermore, rat lung tissue was scanned histologically. The rats were divided into three groups: control, ALI, and treatment with AV-CS-NPs. Results: The AV-CS-NPs that were prepared exhibited clustered semispherical and spherical forms, having an average particle size of approximately 60 nm. These nanoparticles displayed a diverse structure with an uneven distribution of particle sizes. The maximum entrapment efficiency of 95.5% ± 1.25% was achieved. The obtained findings revealed that The minimum inhibitory concentration and minimum bactericidal concentration values were determined to be 5 and 10 ug/ml, respectively, indicating the potent bactericidal effect of the NPs. Also, S. aureus infected rats explored upregulation in the mRNA expression of TLR2 and TLR4 compared to healthy control groups. AV-CS-NP treatment reverses the case where there was repression in mRNA expression of TLR2 and TLR4 compared to S. aureus-treated rats. Conclusion: These NPs can serve as potential candidates for the development of alternative antimicrobial agents.


Assuntos
Lesão Pulmonar Aguda , Aloe , Quitosana , Nanopartículas , Doenças dos Roedores , Ratos , Animais , Quitosana/química , Quitosana/farmacologia , NF-kappa B/farmacologia , Staphylococcus aureus , Receptor 2 Toll-Like , Receptor 4 Toll-Like , Nanopartículas/química , Transdução de Sinais , Antibacterianos/farmacologia , Lesão Pulmonar Aguda/veterinária , Inflamação/veterinária , RNA Mensageiro/farmacologia
2.
Environ Sci Technol ; 57(46): 18151-18161, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37952161

RESUMO

Water-soluble organic matter (WSOM) formed through aqueous processes contributes substantially to total atmospheric aerosol, however, the impact of water evaporation on particle concentrations is highly uncertain. Herein, we present a novel approach to predict the amount of evaporated organic mass induced by sample drying using multivariate polynomial regression and random forest (RF) machine learning models. The impact of particle drying on fine WSOM was monitored during three consecutive summers in Baltimore, MD (2015, 2016, and 2017). The amount of evaporated organic mass was dependent on relative humidity (RH), WSOM concentrations, isoprene concentrations, and NOx/isoprene ratios. Different models corresponding to each class were fitted (trained and tested) to data from the summers of 2015 and 2016 while model validation was performed using summer 2017 data. Using the coefficient of determination (R2) and the root-mean-square error (RMSE), it was concluded that an RF model with 100 decision trees had the best performance (R2 of 0.81) and the lowest normalized mean error (NME < 1%) leading to low model uncertainties. The relative feature importance for the RF model was calculated to be 0.55, 0.2, 0.15, and 0.1 for WSOM concentrations, RH levels, isoprene concentrations, and NOx/isoprene ratios, respectively. The machine learning model was thus used to predict summertime concentrations of evaporated organics in Yorkville, Georgia, and Centerville, Alabama in 2016 and 2013, respectively. Results presented herein have implications for measurements that rely on sample drying using a machine learning approach for the analysis and interpretation of atmospheric data sets to elucidate their complex behavior.


Assuntos
Butadienos , Água , Baltimore , Aerossóis/análise
3.
Gels ; 9(10)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37888353

RESUMO

Skin wound healing is time-consuming and frequently accompanied by bacterial infections and the development of scars. The rise of antibiotic-resistant bacterial strains has sparked a growing interest in naturally occurring bioactive substances, like curcumin, that possess wound-healing capabilities. Silver is a natural antimicrobial agent, and finds extensive use in specialized wound dressings. Silver nanoparticles (AgNPs) were synthesized using an eco-friendly approach, employing curcumin. The prepared nanoparticles have been characterized using TEM, DLS, and zeta potential. The prepared AgNPs were loaded on sodium alginate-co-gum arabic hydrogel. Two hydrogel samples (with and without AgNPs) have been applied for wound healing. The developed silver nanoparticles that were created exhibited effective action against both types of bacteria, namely Gram-negative and Gram-positive. Alg-co-AG-AgNPs demonstrated faster wound healing rates compared to using the control hydrogel sample. The novel dressings of curcumin-silver nanoparticle-incorporated sodium alginate-co-gum arabic hydrogels (Alg-co-AG-AgNPs) exhibited exceptional biocompatibility and have the potential to serve as a wound dressing that possesses antibacterial properties and reduces scarring.

4.
Gels ; 9(8)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37623101

RESUMO

The prevalence of chronic wounds is increasing owing to the expanding population and the growing number of individuals suffering from diabetes. Such a chronic wound continues to be a significant healthcare burden for diabetic patients because it frequently carries a high chance of limb loss due to amputation and reduces survival as a result. Development of innovative wound dressing materials with the potential to stop bacterial infections and accelerate the process of tissue regeneration is needed to increase the effectiveness of diabetic wound healing. In the current study, a co-polymerization process based on a free radical reaction was used to create a hydrogel of polysaccharides blend graft acrylamide (PsB-g-Am). Starch, chitosan, and alginate make up the polysaccharides blend (PsB). The produced hydrogel's structure was characterized using FTIR spectroscopy. The antibacterial activities of silver nanoparticles synthesized through the green method using garlic bulb (Allium sativum) is reported. The silver nanoparticles' physical characteristics were examined using scanning electron microscopy, transmission electron microscopy analysis, and UV-visible spectroscopy and they were found to range in size from 50 to 100 nm. The agar well diffusion technique is used to investigate the antibacterial characteristics. Inclusion of silver nanoparticles in the hydrogels demonstrated concentration-dependent antibacterial behavior against Gram-negative Klebsiella pneumoniae and Gram-positive Staphylococcus aureus during antimicrobial testing of the hydrogels. When hydrogels were applied to diabetic mice, the system was examined for its healing abilities, and positive therapeutic results were obtained in as little as 14 days. Thus, it can be inferred that graft copolymer of chitosan-AgNPs hydrogels can promote healing in chronic wounds over time and can be utilized as an alternative to conventional therapies for chronic wounds (such as those brought on by diabetes) in mouse models.

5.
Odovtos (En línea) ; 25(2)ago. 2023.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1448746

RESUMO

Cells undergo autophagy to save themselves from injury, but progressive autophagy can cause cell death. This study characterized and compared the effect of grape (resveratrol) and tomato (lycopene) extracts and their combination on modulating autophagy-related miRNA and its target gene in squamous cell carcinoma cell line. Docking analysis for extracts and selected genes was performed. Methyl Thiazol Tetrazolium assays were used to assess the cytotoxicity of extracts and their combination toward HEp-2 cells. qRT-PCR was used to quantify changes in gene expression. Data were statistically analyzed. miRNA-20a was identified as a potential effector in laryngeal cancer, and sequestosome-1 (SQSTM1) was its target gene. Docking analysis showed that resveratrol interacted with miRNA-20a and showed less affinity toward SQSTM1. Hydrogen bonds and hydrophobic interactions were predicted. In contrast, lycopene showed less affinity toward miRNA-20a than resveratrol. Increasing doses of resveratrol, lycopene, and their combination induced a statistically significant reduction in mean percent viability and mean fold changes of miRNA-20a and SQSTM1 expression in treated HEp-2 cells. Pearson's correlation showed a statistically significant positive correlation between miRNA-20a and SQSTM1 (R=0.812, p≤0.001). Grape and tomato extracts and their combination display promising cytotoxicity against HEp-2 cells in a dose- and time-dependent fashion. Both extracts reduce the expression of miRNA-20a and SQSTM1 with subsequent inhibition autophagy and promotion of apoptosis in HEp-2 cells.


Las células se someten a autofagia para salvarse de lesiones, pero la autofagia progresiva puede provocar la muerte celular. Este estudio caracterizó y comparó el efecto de los extractos de uva (resveratrol) y tomate (licopeno) y su combinación en la modulación de miARN relacionado con la autofagia y su gen diana en la línea celular de carcinoma de células escamosas. Se realizó análisis de acoplamiento para extractos y genes seleccionados. Se utilizaron ensayos de metil tiazol tetrazolio para evaluar la citotoxicidad de los extractos y su combinación frente a las células HEp-2. qRT-PCR se utilizó para cuantificar los cambios en la expresión génica. Los datos fueron analizados estadísticamente. El miARN-20a se identificó como un efector potencial en el cáncer de laringe y el secuenciasoma-1 (SQSTM1) fue su gen diana. El análisis de acoplamiento mostró que el resveratrol interactuaba con miRNA-20a y mostraba menos afinidad hacia SQSTM1. Se predijeron enlaces de hidrógeno e interacciones hidrofóbicas. Por el contrario, el licopeno mostró menos afinidad hacia el miARN-20a que el resveratrol. El aumento de las dosis de resveratrol, licopeno y su combinación indujo una reducción estadísticamente significativa en el porcentaje medio de viabilidad y los cambios medios en la expresión de miRNA- 20a y SQSTM1 en las células HEp-2 tratadas. La correlación de Pearson mostró una correlación positiva estadísticamente significativa entre miRNA-20a y SQSTM1 (R=0,812, p≤0,001). Los extractos de uva y tomate y su combinación muestran una citotoxicidad prometedora contra las células HEp-2 de forma dependiente de la dosis y el tiempo. Ambos extractos reducen la expresión de miRNA-20a y SQSTM1 con la posterior inhibición de la autofagia y promoción de la apoptosis en células HEp-2.

6.
Gels ; 9(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37504410

RESUMO

Wound healing is a biological process that involves a series of consecutive process, and its impairment can lead to chronic wounds and various complications. Recently, there has been a growing interest in employing nanotechnology to enhance wound healing. Silver nanoparticles (AgNPs) have expanded significant attention due to their wide range of applications in the medical field. The advantages of AgNPs include their easy synthesis, change their shape, and high surface area. Silver nanoparticles are very efficient for topical drug administration and wound healing because of their high ratio of surface area to volume. The efficiency of AgNPs depends on the synthesis method and the intended application. Green synthesis methods offer an eco-friendly approach by utilizing natural sources such as plant extracts and fungus. The characterization of nanoparticles plays an important character, and it is accomplished through the use of several characterization methods such as UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). These techniques are employed to confirm the specific characters of the prepared Silver Nanoparticles. Additionally, the review addresses the challenges and future perspectives of utilizing green-synthesized AgNPs loaded in Polyacrylamide hydrogel for wound healing applications, including the optimization of nanoparticle size, and release kinetics. Overall, this review highlights the potential of green-synthesized AgNPs loaded in Polyacrylamide hydrogel as promising for advanced wound healing therapies. There are different approaches of usage of AgNPs for wound healing such as polyacrylamide -hydrogels, and the mechanism after their antibacterial action, have been exposed.

7.
BMC Chem ; 17(1): 77, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37454143

RESUMO

Modifying the metal surface is one solution to the industry's growing corrosion problem. Thus, via threading approach and insertion of copolymers (CoP5-7) containing polyarylidenes through the internal cavity beta-cyclodextrin ß-CD, novel pseudopolyrotaxanes copolymers (PC5-7) are developed, resulting in mild steel corrosion inhibition. Inhibitors of corrosion based on ß-CD molecules adsorb strongly to metal surfaces because of their many polar groups, adsorption centers, many linkages of side chains, and benzene rings. The corrosion inhibition efficiencies IE % statistics have been revised via the Tafel polarization method and Spectroscopy based on the electrochemical impedance (EIS), with PC7 achieving the highest 99.93% in 1.0 M H2SO4; they are mixed-type inhibitors. The chemical composition of the resulting PCs is determined with Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) is utilized to examine the morphological structure of the produced polymers, and X-ray diffraction is employed to identify crystallinity. Encapsulating CoP5-7 with ß-CD changes the morphological structures and increases the generated PCs' crystallinity. The thermal stability of PCs is studied, indicating the presence of these CoPs within the ß-CD cavities enhances their thermal stability. This research will be a stepping stone for developing high-efficiency anti-corrosion coatings and various industrial applications.

8.
Molecules ; 28(7)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37050003

RESUMO

Silver nanoparticle composites have abundant biomedical applications due to their unique antibacterial properties. In the current work, green tea leaf extract was used as a natural reducing agent to synthesize AgNPs (AgNPs) using microwave irradiation technology. Furthermore, microwave irradiation has been used for the preparation of AgNPs/chitosan (Ch) grafted polyvinyl alcohol (PVA) hydrogel samples. To approve the accomplishment of AgNPs hydrogel polymer, UV-spectrum, TEM, and FT-IR spectrum analyses and the release of silver ions, actions were taken. The wound-healing ability of the prepared hydrogel samples was measured via both the in vitro (fibroblast cells) and the in vivo using rat models. It was found that chitosan-grafted polyvinyl alcohol, including AgNPs, exhibited excellent antibacterial activity against E. coli and S. aureus using the agar diffusion method. It can be said that microwave irradiation was successful in creating a hydrogel that contained silver nanoparticles. A wound that was still open was successfully treated with these composites.


Assuntos
Quitosana , Nanopartículas Metálicas , Ratos , Animais , Prata , Espectroscopia de Infravermelho com Transformada de Fourier , Álcool de Polivinil , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Hidrogéis/farmacologia
9.
Environ Sci Process Impacts ; 25(2): 241-253, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35838080

RESUMO

Aqueous multi-phase processes are significant contributors to organic aerosol (OA) mass in the atmosphere. This study characterizes the formation of water-soluble organic matter during the winter in the eastern United States through simultaneous measurements of water-soluble organic carbon in the gas and particle phases (WSOCg and WSOCp, respectively). The formation of secondary WSOCp occurred primarily through two pathways: (1) absorptive partitioning of oxygenated organics to the bulk OA and (2) aqueous phase processes. WSOCp formation through the former pathway was evident through the relationship between the fraction of total WSOC in the particle phase (Fp) and the total OA concentration. Conversely, evidence for nighttime aqueous WSOCp formation was based upon the strong enhancement in Fp with increasing relative humidity, indicating the uptake of WSOCg to aerosol liquid water (ALW). The Fp-RH relationship was only observed for temperatures between 0-10 °C, suggesting conditions for aqueous multi-phase processes were enhanced during these times. Temperature exhibited an inverse relationship with ALW and a proportional relationship with aerosol potassium. ALW and biomass burning precursors were both abundant in the 0-10 °C temperature range, facilitating aqueous WSOCp formation. To assess the impact of particle drying on the WSOCp concentrations, the particle measurements alternated between ambient and dried channels. No change was observed in the concentration of particles before and after drying, indicating that the WSOCp formed through the uptake of WSOCg into OA and ALW remained in the condensed phase upon particle drying at all temperature ranges. This work contributes to our understanding of sources, pathways, and factors affecting aqueous aerosol formation in the winter.


Assuntos
Poluentes Atmosféricos , Água , Água/análise , Compostos Orgânicos/análise , Estações do Ano , Atmosfera , Aerossóis/análise , Poluentes Atmosféricos/análise
10.
ACS Omega ; 7(43): 38389-38399, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36340118

RESUMO

The reaction of the starting compound, 7-acetyl-4-cyano-1,6-dimethyl-8-phenyl-7,8-dihydroisoquinoline-3(2H)-thione, with some N-aryl-2-chloroacetamides or chloroacetonitrile, in the presence of sodium acetate trihydrate, gave the corresponding substituted 3-methylsulfanyl-7-acetyl-4-cyano-1,6-dimethyl-8-phenyl-7,8-dihydroisoquinolines. Upon heating of the latter compounds with sodium methoxide in methanol, they underwent intramolecular Thorpe-Zeigler cyclization, affording the target isomers 1-amino-2-(substituted)-5,8-dimethyl-6-phenyl-6,7-dihydrothieno[2,3-c]isoquinolines (DHTIQs). The chemical structures of all produced substances were characterized by elemental and spectral analyses. The photophysical characteristics of the produced DHTIIQs (He1-Ph-Cl, He2-Ph-CH3, He3-Ph, and He4-CN) have been investigated as luminous compounds. Potentiodynamic, surface morphology, and theoretical calculations were used to study the behavior of the synthesized DHTIQs as corrosion inhibitors on mild steel in a 1.0 M sulfuric acid solution.

11.
Membranes (Basel) ; 12(10)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36295682

RESUMO

Agricultural drainage water (ADW) represents a potential source for fresh water after receiving appropriate treatments to satisfy the water quality requirements. Desalination of ADW with medium salinity and moderate contamination with organic and inorganic chemical pollutants could provide a techno-economically feasible approach for facing water scarcity in arid areas. The current work presents a conceptual zero liquid discharge ADW desalination system proposed to treat 300,000 m3/d. The system is based on pretreatment to remove impurities harmful to desalination by staged reverse osmosis (RO) membrane. The brine from the last RO stage is treated via thermal vapor compression followed by evaporation in solar ponds to recover more fresh water and salts of economic value. The essential technical features of the proposed system components are formulated. The proposed system components and its technical and economic indicators are deduced using available software for water pretreatment, RO membrane, desalination, thermal desalination, and solar evaporation ponds. The system provides total distilled water recovery of about 98% viz. 294,000 m3/d in addition to recovered salts of 245,000 t/y. The net cost of water production amounts to USD 0.46 /m3. The environmental considerations of the system are addressed and advantages of applying zero liquid discharge system are elucidated.

12.
Sci Rep ; 12(1): 16317, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175463

RESUMO

This study aims to develop an alternating polyketone containing cationic groups in one and four alternating positions for increased functionality. A novel polyarylidene ketone was synthesized using simple condensation polymerization of terephthaldehyde and 2,5-hexane dione (PAK) The physicochemical properties of the resulting polymer were evaluated using Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, UV-Visible absorbance, fluorescence, and SEM investigations. The findings show that the polymer is amorphous, has good thermal stability, and emits red light. It can also be used as a dye adsorbent in aqueous solutions, with high selectivity for the cationic dye methylene blue (MB). The adsorbent efficiency of PAK was measured as a function of pH, dosage, and initial dye concentration; the greatest dye removal of 96 % was obtained at pH 10, 50 mg dosage, and initial dye concentration of 20 ppm. Kinetics and isotherms were studied, showing that the pseudo-second-order model described kinetic data better than Freundlich and Langmuir and revealed a satisfactory chemisorption process. This study suggests that PAK can purify MB dyeing wastewater, remove Zn2+, Cu2+, Ni2+, Co2+, Cd2+, Fe3+ metal ions well, and is selective for Fe3+ and Cu2+; ion adsorption is chelating-based.


Assuntos
Hexanos , Azul de Metileno , Adsorção , Cádmio , Corantes , Cetonas , Águas Residuárias
13.
Sci Rep ; 12(1): 12878, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896584

RESUMO

To develop innovative mesoporous crosslinked poly(azomethine- sulfone)s with environmental applications, a simple Schiff base condensation technique based on barbituric acid BA or condensed terephthaldehyde barbituric acid TBA in their structures as monomeric units are applied. Different analysis methodologies and viscosity measurements identify them as having stronger heat stability and an amorphous structure. The photophysical features of the multi stimuli response MSR phenomenon are observable, with white light emission at higher concentrations and blue light emission at lower concentrations. Their emission characteristics make them an excellent metal ions sensor through diverse charge transfer methods. They can have a better inhibition efficiency and be employed as both mixed-type and active corrosion inhibitors according to their fluorescence emission with metals, demonstrating their capacity to bind with diverse metals. The adsorption of two distinct dye molecules, Methylene blue MB cationic and sunset yellow SY anionic, on the mesoporous structures of the polymers is investigated, revealing their selectivity for MB dye adsorption. Quantum studies support these amazing discoveries, demonstrating a crab-like monomeric unit structure for the one that is heavily crosslinked.


Assuntos
Corantes , Azul de Metileno , Adsorção , Compostos Azo , Corantes/química , Azul de Metileno/química , Porosidade , Sulfonas , Tiossemicarbazonas
14.
Sci Total Environ ; 827: 154209, 2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35240171

RESUMO

Outdoor air pollution is a complex system that is responsible for the deaths of millions of people annually, yet the integration of interdisciplinary data necessary to assess air quality's multiple metrics is still lacking. This case study integrates atmospheric indicators (concentrations of criteria pollutants including particulate matter and gaseous pollutants), traffic indicators (permanent traffic monitoring station data), and social indicators (community responses in Twitter archives) representing the interplay of the three critical pillars of the United Nations' Triple Bottom Line: environment, economy, and society. During the watershed moment of the COVID-19 pandemic lockdowns in Florida, urban centers demonstrated the gaps and opportunities for understanding the relationships, through correlations rather than causations, between urban air quality, traffic emissions, and public perceptions. The relationship between the perception and the traffic variables were strongly correlated, however no correlation was observed between the perception and actual air quality indicators, except for NO2. These observations might consequently infer that traffic serves as people's proxy for air quality, regardless of actual air quality, suggesting that social media messaging around asthma may be a way to monitor traffic patterns in areas where no infrastructure currently exists or is prohibited to build. It also indicates that people are less likely to be reliable sensors to accurately measure air quality due to bias in their observations of traffic volume and/or confirmation biases in broader social discourse. Results presented herein are of significance in demonstrating the capacity for interdisciplinary studies to consider the predictive capacities of social media and air pollution, its use as both lever and indicator of public support for air quality legislation and clean-air transitions, and its ability to overcome limitations of surface monitoring stations.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Mídias Sociais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Controle de Doenças Transmissíveis , Monitoramento Ambiental/métodos , Humanos , Pandemias , Material Particulado/análise
15.
Int J Pharm ; 615: 121539, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35124114

RESUMO

The presence of anti-polyethylene glycol (PEG) antibodies in the systemic circulation might have potential implications for the therapeutic activity of PEGylated products in vivo in the clinic. In order to study the effect of pre-existing anti-PEG antibodies on the in vivo fate and the therapeutic efficiency of PEGylated therapeutics, we developed a BALB/c mouse model by virtue of the intraperitoneal (i.p.) inoculation of hybridoma cells (HIK-M09 and HIK-M11), secreting monoclonal anti-PEG IgM, mimicking the presence of pre-existing anti-PEG antibodies in the blood. In the model, the titers of anti-PEG IgM in the blood increased as a function of hybridoma cells numbers and time after i.p. inoculation. The in vivo levels of anti-PEG IgM decreased in a dose-dependent manner, following i.v. administration of empty PEGylated liposomes. C26 tumor-bearing mice with measurable levels of anti-PEG IgM, receiving i.v. injection of DiR-labeled empty PEGylated liposomes, showed lower levels of liposomal tumor accumulation and higher levels of liver and spleen accumulation, compared to C26 tumor-bearing mice without measurable anti-PEG IgM. This specifies that the presence of anti-PEG IgM in the murine circulation induced accelerated blood clearance of PEGylated liposomes and reduced their tumor accumulation. The biodistribution and antitumor efficacy of commercially available doxorubicin (DXR)-containing PEGylated liposomes, Doxil®, were scrutinized in the anti-PEG IgM mouse model. In C26 tumor-bearing mice having circulating anti-PEG IgM, at 24 h after injection almost no DXR was observed in blood and tumor, and increased DXR accumulation was observed in spleen and liver, compared to tumor-bearing mice with no circulating anti-PEG IgM. The antitumor efficacy of Doxil® was significantly compromised in the C26 tumor-bearing mice in the presence of anti-PEG IgM. These results demonstrate that the anti-PEG IgM mouse model could be a useful prognostic indicator for the therapeutic effectiveness of different formulations of PEGylated therapeutics in pre-clinical studies.


Assuntos
Lipossomos , Polietilenoglicóis , Animais , Imunoglobulina M , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Tecidual
16.
Environ Pollut ; 285: 117451, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34082371

RESUMO

Since early 2020, the world has faced an unprecedented pandemic caused by the novel COVID-19 virus. In this study, we characterize the impact of the lockdown associated with the pandemic on air quality in six major cities across the state of Florida, namely: Jacksonville, Tallahassee, Gainesville, Orlando, Tampa, and Miami. Hourly measurements of PM2.5, ozone, NO2, SO2, and CO were provided by the US EPA at thirty sites operated by the Florida Department of Environmental Protection during mid-February to mid-April from 2015 through 2020. To analyze the effect of the pandemic, atmospheric pollutant concentrations in 2020 were compared to historic data at these cities during the same period from 2015 to 2019. Reductions in NO2 and CO levels were observed across the state in most cities and were attributed to restrictions in mobility and the decrease in vehicle usage amid the lockdown. Likewise, decreases in O3 concentrations were observed and were related to the prevailing NOx-limited regime during this time period. Changes in concentrations of SO2 exhibited spatial variations, concentrations decreased in northern cities, however an increase was observed in central and southern cities, likely due to increased power generation at facilities primarily in the central and southern regions of the state. PM2.5 levels varied temporally during the study and were positively correlated with SO2 concentrations during the lockdown. In March, reductions in PM2.5 levels were observed, however elevations in PM2.5 concentrations in April were attributed to long-range transport of pollutants rather than local emissions. This study provides further insight into the impacts of the COVID-19 pandemic on anthropogenic sources from vehicular emissions and power generation in Florida. This work has implications for policies and regulations of vehicular emissions as well as consequences on the use of sustainable energy sources in the state.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Cidades , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Florida , Humanos , Pandemias , Material Particulado/análise , SARS-CoV-2
17.
Anticancer Agents Med Chem ; 19(12): 1473-1480, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244433

RESUMO

BACKGROUND: Various phenolic phytochemical extracts have been claimed to exhibit different types of biological activity, including anti-inflammatory, anti-oxidative and anti-carcinogenic activity. Carnosol and carnosic acid, extracts of rosemary, are among these phenolic compounds. MATERIALS AND METHODS: CHARMm-based molecular docking was performed to estimate the possible molecular interactions of both carnosic acid and carnosol with the COX-2 active binding site. An MTT assay was used to evaluate HEp-2 cell viability after incubation for 48 hours with low or high concentrations of carnosol, carnosic acid or their combination. The levels of COX-2 were measured in cell lysate by the quantitative indirect ELISA technique. RESULTS: Docking revealed favourable negative binding energies as well as binding interactions of both carnosic acid and carnosol within the binding site of the COX-2 receptor. Carnosic acid showed more favourable binding potential than carnosol. One-way ANOVA and Bonferroni's post hoc tests revealed significant differences in cytotoxicity among cells treated with different concentrations of the rosemary extracts (P< 0.001). ELISA revealed significant reductions in COX-2 protein levels in HEp-2 cells treated with either carnosic acid (-1.42- fold) or carnosol (-3.16-fold) compared to control cells. CONCLUSION: Both rosemary extracts, carnosol and carnosic acid, exert potential cytotoxic effects on the HEp-2 cell line via inhibition of the COX-2 pathway. The combination of carnosol and carnosic acid exerts a stronger cytotoxic effect than either compound alone.


Assuntos
Antineoplásicos/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Rosmarinus/química , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/isolamento & purificação , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Células Hep G2 , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
18.
Drug Dev Ind Pharm ; 43(6): 902-910, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27977311

RESUMO

The present work aimed to prolong the contact time of flurbiprofen (FBP) in the ocular tissue to improve the drug anti-inflammatory activity. Different niosome systems were fabricated adopting thin-film hydration technique and using the nonionic surfactant Span 60. The morphology of the prepared niosomes was characterized by scanning electron microscopy (SEM). Physical characterization by differential scanning calorimetry, X-ray powder diffraction and Fourier transform infrared spectroscopy were conducted for the optimized formula (F5) that was selected on the basis of percent entrapment efficiency, vesicular size and total lipid content. F5 was formulated as 1% w/w Carpobol 934 gel. Pharmacokinetic parameters of FBP were investigated following ocular administration of F5-loaded gel system, F5 niosome dispersion or the corresponding FBP ocular drops to albino rabbits dispersion. Anti-inflamatory effect of F5-loaded carbopol gel was investigated by histopathological examination of the corneal tissue before and after the treatment of inflamed rabbit eye with the system. Results showed that cholesterol content, surfactant type. and total lipid contents had an apparent impact on the vesicle size of the formulated niosomes. Physical characterization revealed reduced drug crystallinity and incidence of interaction with other niosome contents. F5-loaded gel showed higher Cmax, area under the curve (AUC0-12), and thus higher ocular bioavailability than those of the corresponding FBP ocular solution. F5-loaded gel showed a promising rapid anti-inflammatory effect in the inflamed rabbit eye. These findings will eradicate the necessity for frequent ocular drug instillation and thus, improve patient compliance.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Humor Aquoso/metabolismo , Flurbiprofeno/administração & dosagem , Flurbiprofeno/farmacocinética , Lipossomos , Administração Oftálmica , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Composição de Medicamentos , Flurbiprofeno/uso terapêutico , Géis , Injeções Intraoculares , Masculino , Tamanho da Partícula , Coelhos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
19.
Environ Sci Technol ; 50(7): 3626-33, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26910726

RESUMO

This study characterized the effect of drying on the concentration of atmospheric secondary organic aerosol (SOA). Simultaneous measurements of water-soluble organic carbon in the gas (WSOCg) and particle (WSOCp) phases were carried out in Baltimore, MD during the summertime. To investigate the effect of drying on SOA, the WSOCp measurement was alternated through an ambient channel (WSOCp) and a "dried" channel (WSOCp,dry) maintained at ∼35% relative humidity (RH). The average mass ratio between WSOCp,dry and WSOCp was 0.85, showing that significant evaporation of the organic aerosol occurred due to drying. The average amount of evaporated water-soluble organic matter (WSOM = WSOC × 1.95) was 0.6 µg m(-3); however, the maximum evaporated WSOM concentration exceeded 5 µg m(-3), demonstrating the importance of this phenomenon. The systematic difference between ambient and dry channels indicates a significant and persistent source of aqueous SOA formed through reversible uptake processes. The wide-ranging implications of the work are discussed, and include: new insight into atmospheric SOA formation; impacts on particle measurement techniques; a newly identified bias in PM2.5 measurements using the EPA's Federal Reference and Equivalent Methods (FRM and FEM); atmospheric model evaluations; and the challenge in relating ground-based measurements to remote sensing of aerosol properties.


Assuntos
Aerossóis/análise , Dessecação , Compostos Orgânicos/análise , Estações do Ano , Atmosfera/química , Baltimore , Carbono/química , Gases/química , Umidade , Solubilidade , Volatilização , Água/química
20.
JACC Cardiovasc Interv ; 8(7): 972-80, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26003031

RESUMO

OBJECTIVES: This study sought to investigate left atrial (LA) remodeling in relation to blood pressure (BP) and heart rate (HR) after renal sympathetic denervation (RDN). BACKGROUND: In addition to reducing BP and HR in certain patients with hypertension, RDN can decrease left ventricular (LV) mass and ameliorate LV diastolic dysfunction. METHODS: Before and 6 months after RDN, BP, HR, LV mass, left atrial volume index (LAVI), diastolic function (echocardiography), and premature atrial contractions (PAC) (Holter electrocardiogram) were assessed in 66 patients with resistant hypertension. RESULTS: RDN reduced office BP by 21.6 ± 3.0/10.1 ± 2.0 mm Hg (p < 0.001), and HR by 8.0 ± 1.3 beats/min (p < 0.001). At baseline, LA size correlated with LV mass, diastolic function, and pro-brain natriuretic peptide, but not with BP or HR. Six months after RDN, LAVI was reduced by 4.0 ± 0.7 ml/kg/m(2) (p < 0.001). LA size decrease was stronger when LAVI at baseline was higher. In contrast, the decrease in LAVI was not dependent on LV mass or diastolic function (E/E' or E/A) at baseline. Furthermore, LAVI decreased without relation to decrease in systolic BP or HR. Additionally, occurrence of PAC (median of >153 PAC/24 h) was reduced (to 68 PAC/24 h) by RDN, independently of changes in LA size. CONCLUSIONS: In patients with resistant hypertension, LA volume and occurrence of PAC decreased 6 months after RDN. This decrease was independent of BP and HR at baseline or the reduction in BP and HR reached by renal denervation. These data suggest that there is a direct, partly BP-independent effect of RDN on cardiac remodeling and occurrence of premature atrial contractions.


Assuntos
Função do Átrio Esquerdo , Complexos Atriais Prematuros/prevenção & controle , Remodelamento Atrial , Pressão Sanguínea , Frequência Cardíaca , Hipertensão/cirurgia , Rim/irrigação sanguínea , Artéria Renal/inervação , Simpatectomia/métodos , Idoso , Anti-Hipertensivos/uso terapêutico , Complexos Atriais Prematuros/etiologia , Complexos Atriais Prematuros/fisiopatologia , Pressão Sanguínea/efeitos dos fármacos , Ablação por Cateter/efeitos adversos , Resistência a Medicamentos , Feminino , Alemanha , Humanos , Hipertensão/complicações , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Simpatectomia/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
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