24 research outputs found
SiOâ‚‚-coated layered gadolinium hydroxides for simultaneous drug delivery and magnetic resonance imaging
Layered gadolinium hydroxides (LGdH) have significant potential in simultaneous drug delivery and magnetic resonance imaging (MRI). In this work, we synthesized LGdH nanocomposites surface functionalised with SiO₂ nanodots (LGdH@SiO₂). We find these to have good dispersibility in cell culture medium, and a reduced tendency to aggregate compared to their uncoated analogue. Under the optimal reaction conditions, SiO₂ nanodots were evenly spread across the surface of the LGdH particles. We further intercalated ibuprofen (Ibu) and 5-fluorouracil (5FU) into LGdH@SiO₂, and explored the use of the resultant composites for drug delivery in vitro. While the SiO₂ coating could effectively reduce aggregation of the Ibu intercalate prepared by ion exchange from the parent LGdH, it was noted to increase aggregation in the case of the 5FU-loaded systems produced by coprecipitation. With a SiO₂ coating, 5FU release from the composite was almost zero-order at pH 7.4. The LGdH-5FU@SiO₂ composites can effectively inhibit the growth of A549 cells (a human adenocarcinoma cell line). In contrast, the Ibu-loaded materials are highly biocompatible. After SiO₂ modification, LGdH-5FU@SiO₂ retains the same proton relaxivity properties as LGdH-5FU, while LGdH-Ibu@SiO₂ ecomes suitable for use as a negative contrast agent in MRI. Overall, we find the LGdH@SiO₂ nanocomposites are promising materials for theranostic applications
Actividad antiinflamatoria de dos variedades de aceite de semillas de calabaza en un modelo de artritis adyuvante en ratas
The aim of the present research was to evaluate the anti-inflammatory activity of pumpkin seed oils (PSOs) of an Egyptian and European variety, in a rat model of adjuvant arthritis. Edema thickness, plasma tumor necrosis factor-α (TNF-α) and erythrocyte sedimentation rate (ESR) were determined as inflammatory biomarkers while malondialdehyde (MDA) and total antioxidant capacity (TAC) were assessed as indicative of oxidative stress. Chromosomal aberration, sperm shape abnormalities, and DNA fragmentations are cytogenetic parameters which aid in tracing inflammatory and oxidative activity. Phenolic contents and β-carotene were determined in PSOs. The results showed elevated ESR, plasma TNF-α, plasma MDA, liver cellular DNA fragmentation, bone marrow chromosomal aberration, sperm shape abnormalities with a reduction in plasma TAC and body weight gain in an adjuvant arthritis control compared to a healthy control. Administration of low and high doses of either Egyptian or European PSO improved all the aforementioned parameters with variable degrees.El objetivo de la presente investigaciĂłn fue evaluar la actividad antiinflamatoria de aceites de calabaza (PSOs) de variedades egipcia y europea, en un modelo de rata con artritis adyuvante. El espesor del edema, el factor de necrosis tumoral (TNF-α) y la velocidad de sedimentaciĂłn eritrocitaria (ESR) se determinaron como biomarcadores inflamatorios, mientras que el malondialdehĂdo (MDA) y la capacidad antioxidante total (TAC) fueron evaluados como indicativos de estrĂ©s oxidativo. La aberraciĂłn cromosĂłmica, las anomalĂas de la forma del esperma y las fragmentaciones del ADN son parámetros citogenĂ©ticos que ayudan a localizar la actividad inflamatoria y oxidativa. Se determinaron contenidos fenĂłlicos y β-caroteno en PSOs. Los resultados mostraron elevado ESR, TNF-α plasmático, MDA plasmática, fragmentaciĂłn del ADN del hĂgado, aberraciĂłn cromosĂłmica de la mĂ©dula Ăłsea, anomalĂas de la forma espermática con una reducciĂłn del TAC plasmático y un aumento del peso corporal en el control de la artritis adyuvante en comparaciĂłn con el control sano. La administraciĂłn de dosis bajas y altas de PSO egipcia o europea mejorĂł todos los parámetros mencionados en grados variables
Anti-inflammatory activity of two varieties of pumpkin seed oil in an adjuvant arthritis model in rats
The aim of the present research was to evaluate the anti-inflammatory activity of pumpkin seed oils (PSOs) of an Egyptian and European variety, in a rat model of adjuvant arthritis. Edema thickness, plasma tumor necrosis factor-α (TNF-α) and erythrocyte sedimentation rate (ESR) were determined as inflammatory biomarkers while malondialdehyde (MDA) and total antioxidant capacity (TAC) were assessed as indicative of oxidative stress. Chromosomal aberration, sperm shape abnormalities, and DNA fragmentations are cytogenetic parameters which aid in tracing inflammatory and oxidative activity. Phenolic contents and β-carotene were determined in PSOs. The results showed elevated ESR, plasma TNF-α, plasma MDA, liver cellular DNA fragmentation, bone marrow chromosomal aberration, sperm shape abnormalities with a reduction in plasma TAC and body weight gain in an adjuvant arthritis control compared to a healthy control. Administration of low and high doses of either Egyptian or European PSO improved all the aforementioned parameters with variable degrees
An investigation of rhinovirus infection on cellular uptake of poly (glycerol-adipate) nanoparticles
Viral infections represent 44% of newly emerging infections, and as is shown by the COVID-19 outbreak constitute a major risk to human health and wellbeing. Although there are many efficient antiviral agents, they still have drawbacks such as development of virus resistance and accumulation within off-target organs. Encapsulation of antiviral agents into nanoparticles (NPs) has been shown to improve bioavailability, control release, and reduce side effects. However, there is little quantitative understanding of how the uptake of NPs into virally infected cells compares to uninfected cells. In this work, the uptake of fluorescently labeled polymer NPs was investigated in several models of rhinovirus (RV) infected cells. Different multiplicities of RV infections (MOI) and timings of NPs uptake were also investigated. In some cases, RV infection resulted in a significant increase of NPs uptake, but this was not universally noted. For HeLa cells, RV-A16 and RV-A01 infection elevated NPs uptake upon increasing the incubation time, whereas at later timepoints (6 h) a reduced uptake was noted with RV-A01 infection (owing to decreased cell viability). Beas-2B cells exhibited more complex trends: decreases in NPs uptake (cf. uninfected cells) were observed at short incubation times following RV-A01 and RV-A16 infection. At later incubation times (4 h), we found a marked decrease of NPs uptake for RV-A01 infected cells but an increase in uptake with RV-A16 infected cells. Where increases in NPs uptake were found, they were very modest compared to results previously reported for a hepatitis C/ Huh7.5 cell line model. An increase in RV dose (MOI) was not associated with any notable change of NPs uptake. We argue that the diverse endocytic pathways among the different cell lines, together with changes in virus nature, size, and entry mechanism are responsible for these differences. These findings suggest that NPs entry into virally infected cells is a complex process, and further work is required to unravel the different factors which govern this. Undertaking this additional research will be crucial to develop potent nanomedicines for the delivery of antiviral agents
Co-circulation of three camel coronavirus species and recombination of MERS-CoVs in Saudi Arabia
Outbreaks of Middle East respiratory syndrome (MERS) raise questions about the prevalence and evolution of the MERS coronavirus (CoV) in its animal reservoir. Our surveillance in Saudi Arabia in 2014 and 2015 showed that viruses of the MERS-CoV species and a human CoV 229E-related lineage co-circulated at high prevalence, with frequent co-infections in the upper respiratory tract of dromedary camels. viruses of the betacoronavirus 1 species, we found that dromedary camels share three CoV species with humans. Several MERS-CoV lineages were present in camels, including a recombinant lineage that has been dominant since December 2014 and that subsequently led to the human outbreaks in 2015. Camels therefore serve as an important reservoir for the maintenance and diversification of the MERS-CoVs and are the source of human infections with this virus