Mesoporous silica nanoparticle incorporation of essential oils onto synthetic textiles for tailored antimicrobial activity

Healthcare associated infections (HCAI) impose significant financial and environmental problems for modern healthcare settings, therefore it is important to develop novel strategies to combat HCAIs and the causative microorganisms. This study investigates the use of an encapsulated essential oil (EO) antimicrobial coating for textiles in the healthcare environment. The antimicrobial activity of several EOs were studied, individually and in blends, against five microorganisms associated with HCAI (Staphylococcus aureus, methicillin resistant Staphylococcus aureus, Candida albicans, Escherichia coli, and Pseudomonas aeruginosa). A 1:1 blend of cinnamon (CIN) and clove oils (CLO) containing 94.8 % (v/v) eugenol (by GC-MS) showed the highest antimicrobial efficacy and gave a minimum inhibitory concentration (MIC) of less than 0.25% (v/v). Mesoporous silica nanoparticles (MSN) were used to encapsulate volatile EOs. The MSNs displayed narrow size distribution, high surface area and pore size between 1.8-2.2 nm. MSNs, directly loaded with CIN:CLO blend (72 % by mass of MSN), achieved bactericidal values (25-50 mg/mL) against the test microorganisms. Dynamic killing profiles of the EO loaded MSNs against the test microorganisms were recorded. The highest kill rates were observed during the first 15 minutes of contact. Organically modified silica (ormosil) gels were synthesised to provide thin film coverage of synthetic fibres. Gamma-methacryloxypropyltrimethoxysilane (-MPS) was used to attach un-loaded MSNs to the ormosil coating. A layer-by-layer treatment method provided good coverage of synthetic fibres with MSNs, as evidenced by scanning electron microscopy (SEM). Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was used to monitor the layer-by-layer treatment sequence. Head space GC-MS sampling of EO loaded MSN treated textile coupons showed that EO was able to diffuse from the MSN mesopores after being bonded to the synthetic fibres. The EO loaded MSN textile coupons were microbiologically challenged using a method based on AATCC 100. The EO loaded MSN textile coupons displayed good antimicrobial activity over five washing cycles using a method based on (AATCC 61 and 135) thereby indicating a degree of controlled release

Mesoporous silica nanoparticle incorporation of essential oils onto synthetic textiles for tailored antimicrobial activity

Healthcare associated infections (HCAI) impose significant financial and environmental problems for modern healthcare settings, therefore it is important to develop novel strategies to combat HCAIs and the causative microorganisms. This study investigates the use of an encapsulated essential oil (EO) antimicrobial coating for textiles in the healthcare environment. The antimicrobial activity of several EOs were studied, individually and in blends, against five microorganisms associated with HCAI (Staphylococcus aureus, methicillin resistant Staphylococcus aureus, Candida albicans, Escherichia coli, and Pseudomonas aeruginosa). A 1:1 blend of cinnamon (CIN) and clove oils (CLO) containing 94.8 % (v/v) eugenol (by GC-MS) showed the highest antimicrobial efficacy and gave a minimum inhibitory concentration (MIC) of less than 0.25% (v/v). Mesoporous silica nanoparticles (MSN) were used to encapsulate volatile EOs. The MSNs displayed narrow size distribution, high surface area and pore size between 1.8-2.2 nm. MSNs, directly loaded with CIN:CLO blend (72 % by mass of MSN), achieved bactericidal values (25-50 mg/mL) against the test microorganisms. Dynamic killing profiles of the EO loaded MSNs against the test microorganisms were recorded. The highest kill rates were observed during the first 15 minutes of contact. Organically modified silica (ormosil) gels were synthesised to provide thin film coverage of synthetic fibres. Gamma-methacryloxypropyltrimethoxysilane (-MPS) was used to attach un-loaded MSNs to the ormosil coating. A layer-by-layer treatment method provided good coverage of synthetic fibres with MSNs, as evidenced by scanning electron microscopy (SEM). Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was used to monitor the layer-by-layer treatment sequence. Head space GC-MS sampling of EO loaded MSN treated textile coupons showed that EO was able to diffuse from the MSN mesopores after being bonded to the synthetic fibres. The EO loaded MSN textile coupons were microbiologically challenged using a method based on AATCC 100. The EO loaded MSN textile coupons displayed good antimicrobial activity over five washing cycles using a method based on (AATCC 61 and 135) thereby indicating a degree of controlled release

An effect of prostaglandin E1 on the acinar cell of the rat parotid gland

The effects of in vivo administration of prostaglandin E1 (PGE1) on rat parotid gland acinar cells were studied and compared with glands removed from animals which had been either fasted or stimulated to discharge stored secretory granules by an injection of isoproterenol (IPR). Depletion of tissue amylase, increased plasma amylase, and alterations in secretory cell ultrastructure were used to assess the effects of PGE1. Initially following PGE1 administration, the secretory granules enlarged their matrices and lost electron opacity, and numerous fusions between secretory granules occurred. Concomitant with the above events, material having an appearance identical to that within the secretory granules was observed in the acinar lumina and the intercellular spaces. The PGE1-induced release of stored secretory materials from storage granules was transient. Five hours after the onset of hourly PGE1 injections, the biochemical and structural features of the gland were "normal." The effects of PGE1 on the rat parotid gland are discussed. A theory of PGE1 action based on the translocation of ionic calcium is proposed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22258/1/0000695.pd

Separating hyperfine from spin-orbit interactions in organic semiconductors by multi-octave magnetic resonance using coplanar waveguide microresonators

Separating the influence of hyperfine from spin-orbit interactions in spin-dependent carrier recombination and dissociation processes necessitates magnetic resonance spectroscopy over a wide range of frequencies. We have designed compact and versatile coplanar waveguide resonators for continuous-wave electrically detected magnetic resonance, and tested these on organic light-emitting diodes. By exploiting both the fundamental and higher-harmonic modes of the resonators we cover almost five octaves in resonance frequency within a single setup. The measurements with a common pi-conjugated polymer as the active material reveal small but non-negligible effects of spin-orbit interactions, which give rise to a broadening of the magnetic resonance spectrum with increasing frequency

Congested Sidewalks: The Effects of the Built Environment on E-scooter Parking Compliance

With the proliferation of electric scooters (e-scooters) in cities across the world, concerns continue to arise about their parking spots on sidewalks and other public spaces. Research has looked at e-scooter parking compliance and compared compliance to other mobility devices, but research has not yet examined the impacts of the built environment on parking compliance. Using a field observation dataset in Portland, Oregon, and novel GIS data, we attempt to understand the spatial distribution of e-scooter parking and the impact of built features on parking compliance, offering recommendations for policymakers and future research. The results of our study show that 76% of e-scooters observed fail at least one of the Portland’s parking compliance requirements and 59% fail at least two criteria. However, compliance varies spatially and by violation type, indicating that parking compliance (or non-compliance) is dependent on features of the built environment. Parking compliance is significantly higher on blocks with designated e-scooter parking than blocks without designated e-scooter parking. A statistically significant relationship is observed between the amount of legally parkable area on a city block and parking compliance. Parking compliance increases with larger percentages of legally parkable area. This finding can help policymakers prioritize dedicated e-scooter parking for blocks with limited legally parkable area

Suppressor of sable [Su(s)] and Wdr82 down-regulate RNA from heat-shock-inducible repetitive elements by a mechanism that involves transcription termination

Although RNA polymerase II (Pol II) productively transcribes very long genes in vivo, transcription through extragenic sequences often terminates in the promoter-proximal region and the nascent RNA is degraded. Mechanisms that induce early termination and RNA degradation are not well understood in multicellular organisms. Here, we present evidence that the suppressor of sable [su(s)] regulatory pathway of Drosophila melanogaster plays a role in this process. We previously showed that Su(s) promotes exosome-mediated degradation of transcripts from endogenous repeated elements at an Hsp70 locus (Hsp70-αβ elements). In this report, we identify Wdr82 as a component of this process and show that it works with Su(s) to inhibit Pol II elongation through Hsp70-αβ elements. Furthermore, we show that the unstable transcripts produced during this process are polyadenylated at heterogeneous sites that lack canonical polyadenylation signals. We define two distinct regions that mediate this regulation. These results indicate that the Su(s) pathway promotes RNA degradation and transcription termination through a novel mechanism

Reference to index of ledger of the High School of Hobart Town 1850 - 1851.

The School was founded in 1848 by a group of gentleman connected with the Prestbyterian and free churches including Rev. Dr. John Lillie, Minister of St. Andrews Church, Chairman of the Council, T.D.Chapman, who succeeded Lillie as Chairman of the Council of Shareholders, R.W.Nutt, Henry Hopkins, G.W.Walker, R. Officer and W. Robertson, who acted as treasurer.The object of the High School, as originally described,was 'the instruction of youth in the higher brances of learning, as taught in superior classical and mathematical schools in England', the ultimate object being 'to confer on Australian youth the inestimable advantages of an European University'. The school opened in 1850 and 56 boys were enrolled in the first quarter. The number had increased to 81 at the beginning of 1851. By 1859 boarders were being taken and a junior department had been started.In 1885 the rights to the school were handed over to the Christ College Trust and the school became Christ College, surprisingly as J.P.Gell the first Warden of Christ's College originally opposed the foundation of the High School. The Christ College School in fact merged with the Hutchins School and in 1892 the High School building was sold to the new University of Tasmania

Electron microscopy of cytoplasmic crystalloids in rat parotid glands

Crystalloid-containing bodies that may be lysosomes were observed by electron microscopy in acinar and striated duct cells of normal fasted rat parotid glands. The crystalloids varied in number from animal to animal and from lobule to lobule. They consisted of either parallel linear densities with a 5.5 nm periodicity, or of alternating major dense and minor light lines, with a 15 nm distance between successive major lines. It was concluded that the presence of a few such crystalloids in parotid glands of treated rats is not a cytopathic effect and they are significant only when present in large numbers.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23717/1/0000689.pd