90 resultados para AQUEOUS NASAL SPRAY


Relevância:

80.00% 80.00%

Publicador:

Resumo:

In a double-blind placebo-controlled study, we examined the effect of nicotine, a cholinergic agonist, on performance of a prospective memory (ProM) task in young adult volunteers.

Volunteers were required to complete an ongoing lexical decision task while maintaining the ProM task (responding with a different button press to items containing particular target letters). Half of the volunteers were smokers, half were nonsmokers. Half of each group received a single dose (1 mg) of nicotine nasal spray before completing the task; the remaining volunteers received a matched inactive placebo spray.

Nicotine improved performance on the ProM task when volunteers were able to devote resources to that task. Under a variant procedure, where volunteers completed a concurrent auditory monitoring task, ProM performance was impaired under nicotine. Results are discussed in terms of the resource model of ProM, and the arousal model of drug effects.


The data suggest that ProM under the conditions tested here is a resource-needy process, and that nicotine can improve performance by increasing available resources. Increased working memory demands that encourage redirection of resources may impair ProM performance, but the conditions under which these deficits emerge depend upon the subjective allocation of resources across tasks, rather than resource availability per se.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Rationale 

Human and animal studies over the last two decades report that nicotine can improve cognitive performance. Prospective memory (PM), the retrieval and implementation of a previously encoded intention, is also improved by pre-administration of nicotine. As with other nicotine effects, however, predicting precisely how and when nicotine improves the processes engaged by PM has proved less straightforward.

Objective
We present two studies that explore the source of nicotine’s enhancement of PM. Experiment 1 tests for effects of nicotine on preparatory attention (PA) for PM target detection. Experiment 2 asks whether nicotine enhances processing of the perceptual attributes of the PM targets.

Materials and methods
Young adult non-smokers matched on baseline performance measures received either 1 mg nicotine or matched placebo via nasal spray. Volunteers completed novel PM tasks at 15 min post-administration.

Results
Experiment 1 confirmed that pre-administration of nicotine to non-smokers improved detection rate for prospective memory targets presented during an attention demanding ongoing task. There was no relationship between PM performance and measures of preparatory attention. In experiment 2, salient targets were more likely to be detected than non-salient targets, but nicotine did not confer any additional advantage to salient targets.

Conclusion

The present study suggests that nicotinic stimulation does not work to enhance perceptual salience of target stimuli (experiment 2), nor does it work through better deployment of preparatory working attention (experiment 1). An alternative explanation that nicotine promotes PM detection by facilitating disengagement from the ongoing task is suggested as a future line of investigation.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Background There is increasing interest in oxytocin as a therapeutic to treat social deficits in autism spectrum disorders (ASD). The aim of this study was to investigate the efficacy of a course of oxytocin nasal spray to improve social behavior in youth with ASD. Methods In a double-blind, placebo-controlled trial across two Australian university sites between February 2009 and January 2012, 50 male participants aged between 12 and 18 years, with Autistic or Asperger's Disorder, were randomized to receive either oxytocin (n = 26) or placebo (n = 24) nasal sprays (either 18 or 24 International Units), administered twice-daily for 8 weeks. Participants were assessed at baseline, after 4- and 8-weeks of treatment, and at 3-month follow-up. Primary outcomes were change in total scores on the caregiver-completed Social Responsiveness Scale and clinician-ratings on the Clinical Global Impressions-Improvement scale. Secondary assessments included caregiver reports of repetitive and other developmental behaviors and social cognition. Clinical trial registration: Australian New Zealand Clinical Trials Registry www.anzctr.org.au ACTRN12609000513213. Results Participants who received oxytocin showed no benefit following treatment on primary or secondary outcomes. However, caregivers who believed their children received oxytocin reported greater improvements compared to caregivers who believed their child received placebo. Nasal sprays were well tolerated and there was no evidence of increased side effects resulting from oxytocin administration. Conclusions This is the first evaluation of the efficacy for a course of oxytocin treatment for youth with ASD. Although results did not suggest clinical efficacy, further research is needed to explore alternative delivery methods, earlier age of intervention, and the influence of caregiver expectation on treatment response.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Chemiluminescence was observed during the manganese(III), (IV) and (VII) oxidations of sodium tetrahydroborate, sodium dithionite, sodium sulfite and hydrazine sulfate in acidic aqueous solution. From the corrected chemiluminescence spectra, the wavelengths of maximum emission were 689±5 and 734±5 nm when the reactions were performed in sodium hexametaphosphate and sodium dihydrogenorthophosphate/ orthophosphoric acid environments, respectively. The corrected phosphorescence spectrum of manganese(II) sulfate in a solution of sodium hexametaphosphate at 77 K exhibited two peaks with maxima at 688 and 730 nm. The chemical and spectroscopic evidence presented strongly supported the postulation that the emission was an example of solution-phase chemically induced phosphorescence of manganese(II) thereby, confirming earlier predictions that the chemiluminescence from acidic potassium permanganate reactions originated from an excited manganese(II) species.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Photocatalytic oxidation (PCO) process is an effective way to deal with organic pollutants in wastewater which could be difficult to be degraded by conventional biological treatment methods. Normally the TiO2 powder in nanometre size range was directly used as photocatalyst for dye degradation in wastewater. However the titanium dioxide powder was arduous to be recovered from the solution after treatment. In this application, a new form of TiO2 (i.e. pillar pellets ranging from 2.5 to 5.3 mm long and with a diameter of 3.7 mm) was used and investigated for photocatalytic degradation of textile dye effluent. A test system was built with a flat plate reactor (FPR) and UV light source (blacklight and solar simulator as light source respectively) for investigating the effectiveness of the new form of TiO2. It was found that the photocatalytic process under this configuration could efficiently remove colours from textile dyeing effluent. Comparing with the TiO2 powder, the pellet was very easy to recovered from the treated solution and can be reused in multiple times without the significant change on the photocatalytic property. The results also showed that to achieve the same photocatalytic performance, the FPR area by pellets was about 91% smaller than required by TiO2 powder. At least TiO2 pellet could be used as an alternative form of photocatalyst in applications for textile effluent treatment process, also other wastewater treatment processes.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The chemiluminescence arising from the oxidation of ammonium chloride by sodium hypobromite in aqueous alkaline solution includes a series of peaks in the near-ultraviolet, which is not commonly observed in liquid-phase chemiluminescence. The dominant peak in that region has an intensity maximum at 292 nm and smaller peaks are observed at 313, 334 and 356 nm. The emitted photons are of similar energy to the Vergard–Kaplan transition of molecular nitrogen, a major product of this reaction. However, the spectral distribution is different to that of previously reported gas-phase chemiluminescence attributed to the Vergard–Kaplan transition.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper reports an investigation into the temporal stability of aqueous solutions of psilocin and psilocybin reference drug standards over a period of fourteen days. This study was performed using high performance liquid chromatography utilising a (955% vlv) methanol: 10 mM ammonium formate,
pH 3.5 mobile phase and absorption detection at 269 nm. It was found that the exclusion of light significantly prolonged the useful life of standards, with aqueous solutions of both psilocin and psilocybin being stable over a period of seven days.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: In 2002−03 a retrospective audit of the use of surgical antimicrobial prophylaxis (AMP) for elective nasal surgery was undertaken at the Royal Victorian Eye and Ear Hospital (RVEEH). The RVEEH is a publicly funded teaching hospital that provides specialist eye, nose and throat medicine in Victoria, Australia. The aim of the audit was to determine the extent to which the use of antimicrobial prophylaxis in the hospital was consistent with Australian and international evidence-based guidelines and if there was a need for the hospital to develop internal guidelines for the use of AMP.

Methods: The histories of 500 consecutive patients who had undergone nasal surgery within the study period of August 2001 and July 2002 were examined. The data collected from these histories included information such as the patients' age, gender, diagnosis, surgical procedure performed, antimicrobial agents used, and the length of follow up and a range of factors shown in previous studies to increase the risk of surgical site infection.

Results: A total of 306 (72.86%) patients were found to have received antimicrobial agents either prior to admission, during admission or on discharge. Only 24 patients (5.71%) were administered antimicrobials immediately prior to surgery and at no other time.

Conclusions: The findings of this study support the need for further research to examine the appropriateness of the use of AMP at the RVEEH and the need for internal guidelines for its use.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper, for the first time, polypyrrole-coated electrospun nanofibre mats have been used as separation membranes to electrolessly recover Au from aqueous [Au(III)Cl4]− solutions, based on a continuous-flow membrane separation process. With a [Au(III)Cl4]− solution passing through the nanofibre membrane, the Au(III) ions were converted into elemental Au. The gold recovered was deposited on the nanofibre membranes in the form of Au particles, as confirmed by EDX and XPS measurements. It has been found that the polypyrrole-coated electrospun nanofibres are good candidate membrane material for the recovery of Au, and the recovery efficiency is affected by the membrane thickness, the permeate flux rate and the initial [Au(III)Cl4]− concentration.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The use of tris(2,2'-bipyridyl) ruthenium (III) as a chemiluminescent spray reagent spot-test for heroin is discussed. Two forms of the reagent are investigated an aqueous and an anhydrous where both were found to give vastly different results. The aqueous reagent giving slow, low intensity chemiluminescence whilst the anhydrous reagent gave a fast, bright response in the presence of 3,6-diacetylmorphine. The anhydrous reagent is less sensitive the slow, intensity response is characteristic of only two opiates tested 3,6-diacetylmorphine and 3-monoacetylmorphine.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose: To determine whether there is an association between dietary omega-3 (ω-3) fatty acid intake, age, and intraocular pressure (IOP) caused by altered aqueous outflow. Methods: Sprague–Dawley rats were fed either ω-3–sufficient (ω-3+) or ω-3–deficient (ω-3) diets from conception. The diets had 7% lipid content. The ω-3+ diet contained safflower, flaxseed, and tuna oils (5.5:1.0:0.5), and the ω-3 diet contained safflower oil only. Intraocular pressure was measured at 5 to 40 weeks of age under light anesthesia (ω-3+, n = 39; ω-3, n = 48). Aqueous outflow was determined at 45 weeks in a subgroup of animals (ω-3+, n = 15;ω-3, n = 22) using pulsed infusion. Ciliary body tissues (n = 6 per group) were assayed for fatty acid content by thin-layer and gas-liquid chromatography in both diet groups. Results: Animals raised on ω-3+ diets had a 13% decrease in IOP at 40 weeks of age (13.48 ± 0.32 mm Hg vs. 15.46 ± 0.29 mm Hg; P < 0.01). When considered as a change in IOP relative to 5 weeks of age, the ω-3+ group showed a 23% decrease (P < 0.001). This lower IOP in the ω-3+ diet group was associated with a significant increase (+56%; P < 0.001) in outflow facility and a decrease in ocular rigidity (–59%; P < 0.001). The ω-3+ group showed a 3.3 times increase in ciliary body docosahexaenoic acid (P < 0.001). Conclusions: Increasing dietary ω-3 reduces IOP with age because of increased outflow facility, likely resulting from an increase in docosanoids. This indicates that dietary manipulation may provide a modifiable factor for IOP regulation. However, further studies are needed to consider whether this can modify the risk for glaucoma and can play a role in treatment of the disease.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This review article focuses primarily on the work carried in our laboratories over the last few years using luminescent and colorimetric sensors, where the anion recognition occurs through hydrogen bonding in organic or aqueous solvents. This review begins with the story of the discovery of fluorescent photoinduced electron transfer (PET) sensors for anions using charged neutral urea or thiourea receptors where both fluorescent and NMR spectroscopic methods monitored anion recognition. This work led to the development of dual luminescent and colorimetric anion sensors based on the use of the ICT based naphthalimide chromophore, where ions such as fluoride gave rise to changes in both the fluorescence and the absorption spectra of the sensors, but at different concentrations. Here, the former changes were due to hydrogen bonding interactions, whereas the latter was due to the deprotonation of acidic protons, giving rise to the formation of the bifluoride anion (HF2−). Modification of the 4-amino-l,8-naphthalimide moiety has facilitated the formation of colorimetric anion sensors that work both in organic or aqueous solutions. Such charge neutral receptor motifs have also been incorporated into organic scaffolds with norbomyl and calixarene backbones, which have enabled us to produce anion directed self-assembled structures.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Nasopharyngeal oxygen (NPO) therapy may overcome some of the difficulties associated with nasal prongs and facemask oxygen delivery devices. In response to a lack of published studies of NPO therapy in adults, we conducted a prospective randomised crossover trial to compare the effectiveness of NPO, nasal prongs (NP) and facemasks (FM) when used in an adult population (n=37) from the intensive care unit and general hospital wards. We measured oxygen saturation (Sp[O.sub.2]) using pulse oximetry, oxygen flow (litres per minute), respiration rate (per minute) and comfort using a horizontal visual analogue scale. All three devices were effective in maintaining a Sp[O.sub.2] of [greater than or equal to]95% (NP 97.0[+ or -]1.9, NPO 97.7[+ or -]1.7, FM 98.8[+ or -]1.3%). NPO therapy consumed less oxygen than NP and FM therapy (NP 2.6[+ or -]1.0, NPO 2.2[+ or -]0.9, FM 6.1[+ or -]0.4 l/min, P <0.001). There was no significant difference in patients' respiratory rates (NP 19.9[+ or -]3.2, NPO 19.9[+ or -]3.0, FM 19.8[+ or -]3.1 per minute, P=0.491). In terms of comfort, patients rated NP higher than NPO and FM using a horizontal visual analogue scale (100 mm=most comfortable) (NP 65.5[+ or -]14.3, NPO 62.8[+ or -]19.4, FM 49.4[+ or -]21.4 mm, P <0.001). We conclude that for adult patients, nasal prongs and nasopharyngeal oxygen therapy consume less oxygen and provide greater comfort than facemasks while still maintaining Sp[O.sub.2] [greater than or equal to]95%.