33 research outputs found
Spearmint (\u3cem\u3el\u3c/em\u3e-carvone) Oil and Wintergreen (methyl salicylate) Oil Emulsion is an Effective Immersion Anesthetic of Fishes
This study evaluates the effects of a spearmint (/-carvone) and wintergreen oil (methyl salicylate) emulsion (CMSE) on age 1 landlocked Atlantic salmon Salmo salar sebago (hereafter salmon). Salmon were immersed in either 257 ”l/L CMSE or 75 mg/L tricaine methanesulfonate (MS-222) to induce anesthesia (stage 4), useful for emersion and noninvasive husbandry procedures, and then salmon were recovered in fresh water. Induction was quicker in the CMSE group; however, recovery was quicker in the MS-222 group. A second experiment was conducted in which salmon were immersed in 257 ”l/L CMSE for 8.5 min, or 75 mg/L MS-222 for 8.5 min in order to compare electrocardiographs during deeper anesthesia (stage 5) between salmon continuously immersed in CMSE to those continuously immersed in MS-222. Because salmon remained sedated longer after CMSE exposure than after MS-222 exposure, a third group of salmon was immersed in 257 ”l/L CMSE for just 2.5 min before undergoing the 6-min electrocardiograph procedure. Anesthesia induction rates, recovery rates, and electrocardiographs of salmon anesthetized with CMSE were comparable to salmon anesthetized with MS-222. Salmon anesthetized with CMSE and then transferred immediately to fresh water had more stable heart rates than salmon anesthetized with either MS-222 or CMSE continuously. Salmon bathed continuously in CMSE showed clinical signs of increasing anesthetic depth including decreasing heart rate, decreasing respiration rate and electrocardiograph abnormalities. The CMSE, with its mint and wintergreen concentrations less than in household products such as chewing gum, toothpaste, and mouthwash, is a potent, rapid-acting immersion fish anesthetic comparable to MS-222 for stages 4 and 5 anesthesia
Lithium-Mediated Zincation of Pyrazine, Pyridazine, Pyrimidine and Quinoxaline.
International audienc
Contact lenses delivering nitric oxide under daylight for reduction of bacterial contamination
Ocular infection due to microbial contamination is one of the main risks associated with the wearing of contact lens, which demands novel straightforward strategies to find reliable solutions. This contribution reports the preparation, characterization and biological evaluation of soft contact lenses (CL) releasing nitric oxide (NO), as an unconventional antibacterial agent, under daylight exposure. A tailored NO photodonor (NOPD) was embedded into commercial CL leading to doped CL with an excellent optical transparency (transmittance = 100%) at λ ℠450 nm. The NOPD results homogeneously distributed in the CL matrix where it fully preserves the photobehavior exhibited in solution. In particular, NO release from the CL and its diffusion in the supernatant physiological solution is observed upon visible light illumination. The presence of a blue fluorescent reporting functionality into the molecular skeleton of the NOPD, which activates concomitantly to the NO photorelease, allows the easy monitoring of the NO delivery in real-time and confirms that the doped CL work under daylight exposure. The NO photoreleasing CL are well-tolerated in both dark and light conditions by corneal cells while being able to induce good growth inhibition of Staphylococcus aureus under visible light irradiation. These results may pave the way to further engineering of the CL with NOPD as innovative ocular devices activatable by sunlight
Spoon-shaped polymer waveguides to excite multiple plasmonic phenomena: A multisensor based on antibody and molecularly imprinted nanoparticles to detect albumin concentrations over eight orders of magnitude
A polymeric multimode waveguide, characterized by a pioneering spoon-shaped geometry, was herein proposed for the first time to devise Surface Plasmon Resonance (SPR) biochemical sensors. The plasmon excitation was enabled by layering a gold nanofilm of âŒ60 nm onto the spoon-waveguide. As a consequence of the waveguide's extra-ordinary geometry, two distinct sensing regions were identified: a planar one, located on the spoon's neck, and a concave one on the bowl, with angled surfaces. The bulk sensitivity (Sn) is correlated both to the way the light was launched in/collected from the sensor (parallel or orthogonal to the main axis of the waveguide) and to the sensing area interrogated (planar-neck or angled-bowl), indicating that the sensor's performance can be conveniently tuned, depending on the chosen measuring configuration. The SPR sensor's characterization showed Sn equal to 750 nm/RIU for the neck and to 950 nm/RIU for the bowl. To further inspect the peculiar sensing-features and assess the application niches, the spoon-shaped waveguide was functionalized with two kinds of receptors, both specific for human serum albumin (HSA): an antibody on the bowl region (high Sn); molecularly imprinted nanoparticles (nanoMIPs) on the neck region (low Sn). The experimental results showed a limit of detection (LOD) for the immune-sensor of 280 pM and an LOD for the nanoMIP-sensor of 4.16 fM. The overall response of the HSA multi-sensor encompassed eight orders of magnitude, suggesting that the spoon-shaped waveguide's provides multi-scale detection and holds potential to devise multi-analyte sensing platforms
Synthesis and characterization of new tyrosine capped anisotropic silver nanoparticles and their exploitation for the selective determination of iodide ions
The assessment of the iodine status of natural waters is crucial for focusing future strategies for controlling and monitoring iodine deficiency disorders (IDD). Nanoparticles have been increasingly used as sensors for several organic and inorganic analytes. In this study, we report the synthesis of new Tyrosine Capped Anisotropic Silver Nanoparticles (AgNPs). The AgNPs were characterized by TEM, UVâvis spectroscopy, and polarized and depolarized dynamic light scattering measurements, and were used for the quantitative determination of iodide ions in the presence of excess chloride ions. Both anions gave rise to an etching of the tips of the nanoprims converting them in rounded nanoplates. However, iodide ions perform this etching much better than chloride ones, allowing for their selective determination in tap waters. Fluoride and bromide anions give rise to a more efficient etching than chloride ions, but their presence does not interfere with iodide determination. This method was also used to determine the concentration of iodide in a sample of drinking water
Preclinical evidence of enhanced analgesic activity of duloxetine complexed with succinyl-ÎČ-cyclodextrin: A comparative study with cyclodextrin complexes
Chronic pain represents one of the most important public health problems, with a great prevalence of comorbidity with depression and cognitive decline. Antidepressants such as duloxetine, a serotonin-norepinephrine reuptake inhibitor, represent an essential part of the therapeutic strategy for chronic pain management in addition to classical analgesics. Duloxetine is endowed with good efficacy and a good profile of safety and tolerability. Yet, duloxetine is metabolized by the cytochrome P450 system 2D6 and 1A2 (CYP2D6 and CYP1A2) and it exhibits moderate inhibitory activity on CYP2D6, resulting in side effects and metabolic interactions that may occur on a long term therapeutic schedule. Cyclodextrins (CyDs) are used in pharmaceutical applications for numerous purposes, including the improvement of drug bioavailability. In order to evaluate their effects on the activity of duloxetine, we first spectrophotometrically studied the hostâguest complexes obtained combining duloxetine and different ÎČ-CyD derivatives (ÎČ-CyD, ÎČ-CyDen-c-(Glu-Glu), and succinyl-ÎČ-CyD) and then performed in vivo and in vitro studies. Among duloxetine/CyDs complexes, succinyl-ÎČ-CyD ameliorated the analgesic activity of duloxetine in the tail flick test and in the formalin test in mice and significantly protected the drug from CYP2D6 metabolism
New fluorescent-labelled nanoparticles: synthesis, characterization and interactions with cysteine and homocysteine to evaluate their stability in aqueous solution
Fluorescent-labelled nanoparticles conjugate the SPR of nanomaterials as well as the fluorescence properties of the capping dye. In this work, we report a study on the synthesis of fluorescent l-tyrosine (l-Tyr) and fluorescein (Fluo)-capped silver nanoparticles (AgNPs) carried out by a fine-tuning of the analytical concentration of the reagents. The AgNPs have been characterized by TEM, UVâVis, ATRâFTIR, and photoluminescence (PL) spectroscopy and DLS. The adsorption of cysteine and homocysteine on the surface of the nanoparticles has been studied to evaluate their overall evolution in solution and their possible interactions with more complex systems, such as proteins. Opposed to homocysteine, cysteine induces aggregation either of tyrosine- and fluorescein-capped nanoparticles, which are therefore promising systems for the discrimination of biothiols. Furthermore, tyrosine-capped AgNPs, in spite of the better coordinating characteristics of this amino acid with respect to fluorescein, show aggregation abilities with cysteine greater than the fluorescein-capped ones that are unexpectedly more stable and thus less prone to aggregation phenomena
Enhancing the Anticancer Activity of Sorafenib through Its Combination with a Nitric Oxide Photodelivering ÎČ-Cyclodextrin Polymer
In this contribution, we report a strategy to enhance the therapeutic action of the chemother-apeutic Sorafenib (SRB) through its combination with a multifunctional ÎČ-cyclodextrin-based polymer able to deliver nitric oxide (NO) and emit green fluorescence upon visible light excitation (PolyCDNO). The basically water-insoluble SRB is effectively encapsulated in the polymeric host (1 mg mLâ1 ) up to a concentration of 18 ”g mLâ1 . The resulting host-guest supramolecular complex is able to release SRB in sink conditions and to preserve very well the photophysical and photochemical properties of the free PolyCDNO, as demonstrated by the similar values of the NO release and fluorescence emission quantum efficiencies found. The complex PolyCDNO/SRB internalizes in HEP-G2 hepa-tocarcinoma, MCF-7 breast cancer and ACHN kidney adenocarcinoma cells, localizing in all cases mainly at the cytoplasmic level. Biological experiments have been performed at SRB concentrations below the IC50 and with light doses producing NO at nontoxic concentrations. The results demonstrate exceptional mortality levels for PolyCDNO/SRB upon visible light irradiation in all the different cell lines tested, indicating a clear synergistic action between the chemotherapeutic drug and the NO. These findings can open up exciting avenues to potentiate the anticancer action of SRB and, in principle, to reduce its side effects through its use at low dosages when in combination with the photo-regulated release of NO
Larval ethanol exposure alters free-running circadian rhythm and per Locus transcription in adult D. melanogaster period mutants
Visible light-activatable multicargo microemulsions with bimodal photobactericidal action and dual colour fluorescence
In this contribution we report the design, preparation, and physico-chemical, photophysical and photochemical characterization of photoactivatable microemulsions (MEs) based on LabrasolÂź, isopropanol and LauroglycolÂź FCC as a surfactant, co-surfactant and oily phase, respectively. The MEs co-incorporate, in their oil phase, two lipophilic guests such as a red emitting singlet oxygen (1O2) photosensitizer (PS) and a tailored green emitting nitric oxide (NO) photodonor (NOPD). These two chromofluorogenic units absorb in different spectral windows of the visible range, and their individual photophysical and photochemical properties are well-conserved when co-entrapped in the microemulsions. These features permit the PS and NOPD to operate either individually or in tandem resulting in (i) red, green or both fluorescence emission, (ii) photogeneration of cytotoxic 1O2, NO or both and (iii) amplified photobactericidal action against Staphylococcus aureus due to the combined effect of these two antibacterial agents