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1.
Drug Des Devel Ther ; 18: 899-908, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38533429

RESUMEN

Purpose: Co-administering multiple intravenous (IV) agents via Y-connectors is a common practice in hospitalised and fasting surgical patients. However, there is a lack of reliable data confirming the physical compatibility of some combinations including IV oxycodone, a drug that is gaining increasing popularity in the perioperative period. Concern regarding physical drug incompatibilities precludes concurrent coadministration with other common drugs through a single lumen. This can result in the cessation of infusions to allow the administration of other medications, resulting in exacerbation of acute pain. This study aims to evaluate the physical compatibility of IV oxycodone with some commonly co-administered drugs and IV fluids. Methods: Mixtures of oxycodone (1mg.mL-1) and the tested drugs and IV fluids were prepared in a ratio of 1:1. The mixtures were examined at 0 and 60 minutes from mixing and assessed using the European Conference Consensus Standards. This involved visual inspection (precipitation, turbidity, colour change, gas formation), spectrophotometry, and pH change. The tested drugs included ketamine, tramadol, clonidine, vancomycin, piperacillin/tazobactam, dexmedetomidine, cefotaxime, gentamicin, and paracetamol. In addition, the commonly used IV fluids tested included glucose 5% + sodium chloride 0.9% + 60 mmol potassium chloride, plasmalyte + dextrose 5%;plasmalyte + dextrose 5% + 55 mmol potassium chloride, plasmalyte + dextrose 5% + 55mmol potassium acetate, plasmalyte + dextrose 5% + 55mmol potassium dihydrogen phosphate, Hartmann's solution, Standard pediatric Total Parenteral Nutrition (TPN) 20/100 and TPN 25/150. Results: IV oxycodone (1 mg.mL-1) showed no visual changes; no spectrophotometric absorption variability at 350, 410, or 550nm; and no pH changes of >0.5 at 0 or 60 minutes with any of the tested drugs or fluids in the concentrations tested. Conclusion: According to European Consensus Conference Standards, IV Oxycodone at 1 mg.mL-1 is physically compatible in a ratio of 1:1 v/v with all investigated drugs and fluids tested for at least 60 minutes.


Asunto(s)
Oxicodona , Vancomicina , Humanos , Niño , Infusiones Intravenosas , Cloruro de Potasio , Glucosa
2.
Dalton Trans ; 52(40): 14517-14526, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37781733

RESUMEN

The crystal structure of YbSbO4 was determined from powder X-ray diffraction data using the Rietveld method. YbSbO4 is found to be monoclinic and isostructural to α-PrSbO4. We have also tested the influence of pressure on the crystal structure up to 22 GPa by synchrotron powder X-ray diffraction. No phase transition was found. The P-V equation of state and axial compressibilities were determined. Experiments were combined with density-functional theory calculations, which provided information on the elastic constants and the influence of pressure in the crystal structure and Raman/infrared phonons. Results are compared with those from other orthoantimonates. Reasons for the difference in the high-pressure behaviour of YbSbO4 compared with most antimony oxides will be discussed.

3.
J Phys Chem Lett ; 14(7): 1762-1768, 2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36762867

RESUMEN

We report diffuse reflectivity measurements in InNbO4, ScNbO4, YNbO4, and eight rare-earth niobates. A comparison with established values of the bandgap of InNbO4 and ScNbO4 shows that Tauc plot analysis gives erroneous estimates of the bandgap energy. Conversely, accurate results are obtained considering excitonic contributions using the Elliot-Toyozawa model. The bandgaps are 3.25 eV for CeNbO4, 4.35 eV for LaNbO4, 4.5 eV for YNbO4, and 4.73-4.93 eV for SmNbO4, EuNbO4, GdNbO4, DyNbO4, HoNbO4, and YbNbO4. The fact that the bandgap energy is affected little by the rare-earth substitution from SmNbO4 to YbNbO4 and the fact that they have the largest bandgap are a consequence of the fact that the band structure near the Fermi level originates mainly from Nb 4d and O 2p orbitals. YNbO4, CeVO4, and LaNbO4 have smaller bandgaps because of the contribution from rare-earth atom 4d, 5d, or 4f orbitals to the states near the Fermi level.

4.
MRS Commun ; 12(3): 358-364, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35492383

RESUMEN

Low-energy X-rays have a predominant role in medical diagnostic applications, grown tremendously during recent Covid-19 pandemic times. Synthesis of stable, PMMA/polystyrene-BiI3 composites has been done through a facile, low-cost, dry-tumble mixing technique for direct X-ray detector applications. Comparative analysis of structural, optical, and photocurrent responses upon irradiation with low-energy X-rays (30 and 60 kV) ensue that PS-BiI3 demonstrates high SNR 3300, sensitivity 189 µC Gy-1 cm-3 and fast response time 30 ms, at dose rate 1.68 mGy s-1, affirming the composite to be prospective candidate for low-energy, room-temperature, direct X-ray detectors under low bias conditions. Supplementary Information: The online version contains supplementary material available at 10.1557/s43579-022-00185-6.

5.
ACS Omega ; 7(3): 3099-3108, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35097305

RESUMEN

The effect of high pressure on the structure of orthorhombic Mn3(VO4)2 is investigated using in situ Raman spectroscopy and X-ray powder diffraction up to high pressures of 26.2 and 23.4 GPa, respectively. The study demonstrates a pressure-induced structural phase transition starting at 10 GPa, with the coexistence of phases in the range of 10-20 GPa. The sluggish first-order phase transition is complete by 20 GPa. Importantly, the new phase could be recovered at ambient conditions. Raman spectra of the recovered new phase indicate increased distortion and as a consequence the lowering of the local symmetry of the VO4 tetrahedra. This behavior is different from that reported for isostructural compounds Zn3(VO4)2 and Ni3(VO4)2 where both show stable structures, although almost similar anisotropic compression of the unit cell is observed. The transition observed in orthorhombic Mn3(VO4)2 could be due to the internal charge transfer between the cations, which favors the structural transition at lower pressures and the eventual recovery of the new phase even upon pressure release in comparison to other isostructural compounds. The experimental equation of state parameters obtained for orthorhombic Mn3(VO4)2 match excellently with empirically calculated values reported earlier.

6.
J Phys Condens Matter ; 34(13)2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-34986466

RESUMEN

In this article we report the synthesis, characterization and high pressure (HP) investigation on technologically important, rare earth orthotantalate, EuTaO4. Single phase polycrystalline sample of EuTaO4has been synthesized by solid state reaction method adopting monoclinic M'-type fergusonite phase with space groupP2/c. Structural and vibrational properties of as synthesized compound are investigated using synchrotron based x-ray powder diffraction, and Raman spectroscopic techniques respectively. Both the techniques show presence of an isostructural, first order, reversible phase transition near 17 GPa. Bulk modulus obtained by fitting the experimental pressure volume data for low pressure and HP phase is 136.0(3) GPa and 162.8(21) GPa. HP phase is accompanied by an increase in coordination number around Ta atom from 6 to 8. First principles calculations under the frame work of density functional theory also predicts the isostructural phase transition and change in coordination around Ta atom, corroborating the experimental findings.

7.
J Clin Pharm Ther ; 46(2): 388-394, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33090559

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Pharmacists play an integral role in paediatric patient care by ensuring the safe and optimal use of medications. There are increasing demands on pharmacists' time and challenges to meet them within allocated resources, and therefore, it is important to ensure that resources are used efficiently. Patient prioritization tools for clinical pharmacists have been proposed via many studies, but are generally adult-based and/or have not been validated to confirm their effectiveness. The aim of this study was to create, pilot and validate a patient prioritization tool to be used by pharmacists providing clinical pharmacy services to paediatric patients. METHODS: A two-phase (retrospective and prospective) observational audit of pharmacists' interventions collected via notes made on their ward handover information sheets and patient case notes was conducted over a 2-year period in a tertiary paediatric hospital. A patient prioritization tool was created based on pharmacists' interventions in real time. This tool could be used at the start of the working day (without the need to review the patient or their case notes) to identify patients who would benefit most from a clinical pharmacist review. The tool was validated for effectiveness and selectivity. RESULTS AND DISCUSSION: The tool was easy to use and effective in identifying that 43% of paediatric inpatients did not require a routine clinical pharmacist review. It had 98% specificity in identifying patients who require a pharmacist intervention. It could be easily used at the start of the day to select patients for pharmacist review. WHAT IS NEW AND CONCLUSION: A new patient prioritization tool has been developed and validated for identifying paediatric inpatients requiring clinical pharmacist review.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas/organización & administración , Hospitales Pediátricos/organización & administración , Servicio de Farmacia en Hospital/organización & administración , Australia , Eficiencia Organizacional , Humanos , Conciliación de Medicamentos , Rol Profesional , Reproducibilidad de los Resultados , Medición de Riesgo , Centros de Atención Terciaria/organización & administración
8.
ACS Omega ; 5(5): 2148-2158, 2020 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-32064375

RESUMEN

We explore the potential of Tb- and Yb-doped InVO4, InTaO4, and InNbO4 for applications as phosphors for light-emitting sources. Doping below 0.2% barely change the crystal structure and Raman spectrum but provide optical excitation and emission properties in the visible and near-infrared (NIR) spectral regions. From optical measurements, the energy of the first/second direct band gaps was determined to be 3.7/4.1 eV in InVO4, 4.7/5.3 in InNbO4, and 5.6/6.1 eV in InTaO4. In the last two cases, these band gaps are larger than the fundamental band gap (being indirect gap materials), while for InVO4, a direct band gap semiconductor, the fundamental band gap is at 3.7 eV. As a consequence, this material shows a strong self-activated photoluminescence centered at 2.2 eV. The other two materials have a weak self-activated signal at 2.2 and 2.9 eV. We provide an explanation for the origin of these signals taking into account the analysis of the polyhedral coordination around the pentavalent cations (V, Nb, and Ta). Finally, the characteristic green (5D4 → 7F J ) and NIR (2F5/2 → 2F7/2) emissions of Tb3+ and Yb3+ have been analyzed and explained.

9.
Inorg Chem ; 57(16): 10265-10276, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30052035

RESUMEN

In this work, we present an experimental and theoretical study of the effects of high pressure and high temperature on the structural properties of olivine-type LiNiPO4. This compound is part of an interesting class of materials primarily studied for their potential use as electrodes in lithium-ion batteries. We found that the original olivine structure (α-phase) is stable up to ∼40 GPa. Above this pressure, the onset of a new phase is observed, as put in evidence by the X-ray diffraction (XRD) experiments. The structural refinement shows that the new phase (known as ß-phase) belongs to space group Cmcm. At room temperature, the two phases coexist at least up to 50 GPa. A complete conversion to the ß-phase was only obtained at high-pressure and high-temperature conditions (973 K, 6.5 GPa), as confirmed by both XRD and Raman spectroscopy. Ab initio calculations support the same structural sequence. The need of high-temperature conditions to obtain the complete transformation of the α-phase into the ß-phase is indicative of the existence of a kinetic barrier for the phase transition. Here, we report the evolution of crystallographic parameters as a function of pressure for both phases, comparing them with the theoretical predictions. We also discuss the influence of pressure on the polyhedral units and report room-temperature equations of state. The dependence of the Raman phonons of both phases on pressure is also studied, assigning to each phonon its respective symmetry by comparison with the results of the ab initio simulations.

10.
Inorg Chem ; 57(12): 6973-6980, 2018 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-29877695

RESUMEN

Negative thermal expansion material TaVO5 is recently reported to have pressure induced structural phase transition and irreversible amorphization at 0.2 and above 8 GPa, respectively. Here, we have investigated the high pressure phase of TaVO5 using in situ neutron diffraction studies. The first high pressure phase is identified to be monoclinic P21/ c phase, same as the low temperature phase of TaVO5. On heating, amorphous TaVO5 transformed to a new crystalline phase, which showed signatures of higher coordination of vanadium indicating pressure induced amorphization (PIA). PIA observed in TaVO5 might be due to the kinetic hindrance of pressure induced decomposition (PID) into a compound with higher coordination of vanadium. Mechanism of PIA observed in TaVO5 is investigated by carrying out ex situ Raman, XRD, XPS, and XAS measurements. We have also proposed a pressure-temperature phase diagram of TaVO5 qualitatively delineating the phase boundaries between the ambient orthorhombic, monoclinic, and amorphous phases.

11.
PLoS One ; 13(1): e0190577, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29298359

RESUMEN

There is increasing interest to administer ibuprofen as a continuous infusion instead of a traditional bolus for treating Patent Ductus Arteriosus (PDA). However, its compatibility data with commonly used drugs in the neonatal period, including parenteral nutrition (PN) and lipids is unavailable. The aim is to determine the compatibility of intravenous ibuprofen lysine with various ANZNN parenteral nutrition consensus group standard neonatal PN formulations and lipids. The PN and lipid solutions used in a tertiary neonatal unit were obtained. These included a Starter, Standard Preterm and low carbohydrate PN, and IV SMOF lipid admixture (SMOFLipid 20% 15 mL; Vitalipid N infant 4 mL, Soluvit N 1 mL) plus vitamin mixtures. 10% glucose was used as a control. 1:1 mixtures of different concentrations (1.25 to 5mg/mL) of ibuprofen lysine and each of the PN/glucose/lipid formulations were made. Samples were taken at hourly intervals for a total of 4 hours and tested for both physical (visual assessment, pH and microscopy) and chemical compatibility (High Performance Liquid Chromatography analysis). Zeta potential and particle diameter were measured for SMOF lipid admixture and ibuprofen combination to assess emulsion stability. 24 hour stability of ibuprofen dilution in 5 mL BD Luer-lok polypropylene syringes at 25°C was also assessed. Most PN formed opaque solutions when mixed with ibuprofen 2.5 and 5mg/mL solutions. However, ibuprofen dilution of 1.25mg/mL produced clear, colourless solutions with no microscopic particles when mixed with all PN/glucose/lipid formulations tested. Ibuprofen was chemically stable with all PN and SMOF lipid admixture, for a period of 4 hours. The zeta potential and particle diameter were within acceptable limits. Ibuprofen lysine was stable over 24 hours in Luer-lok polypropylene syringes. Ibuprofen 1.25mg/mL is physically and chemically compatible with 10% glucose, starter PN, standard preterm and low carbohydrate PN, and SMOF lipid admixture plus vitamins for a period of four hours, which is the maximum time they could be in an admixture during a continuous infusion.


Asunto(s)
Conducto Arterioso Permeable/tratamiento farmacológico , Ibuprofeno/administración & dosificación , Lípidos/administración & dosificación , Nutrición Parenteral , Cromatografía Líquida de Alta Presión , Humanos
12.
Inorg Chem ; 56(9): 5420-5430, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28422488

RESUMEN

The high-pressure behavior of technologically important visible-light photocatalytic semiconductor InNbO4, adopting a monoclinic wolframite-type structure at ambient conditions, was investigated using synchrotron-based X-ray diffraction, Raman spectroscopic measurements, and first-principles calculations. The experimental results indicate the occurrence of a pressure-induced isostructural phase transition in the studied compound beyond 10.8 GPa. The large volume collapse associated with the phase transition and the coexistence of two phases observed over a wide range of pressure shows the nature of transition to be first-order. There is an increase in the oxygen anion coordination number around In and Nb cations from six to eight at the phase transition. The ambient-pressure phase has been recovered on pressure release. The experimental pressure-volume data when fitted to a Birch-Murnaghan equation of states yields the value of ambient pressure bulk modulus as 179(2) and 231(4) GPa for the low- and high-pressure phases, respectively. The pressure dependence of the Raman mode frequencies and Grüneisen parameters was determined for both phases by experimental and theoretical methods. The same information is obtained for the infrared modes from first-principles calculations. Results from theoretical calculations corroborate the experimental findings. They also provide information on the compressibility of interatomic bonds, which is correlated with the macroscopic properties of InNbO4.

13.
J Phys Condens Matter ; 29(5): 055401, 2017 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-27941236

RESUMEN

The high-pressure (HP) behaviour of scandium vanadate (ScVO4) is investigated under non-hydrostatic compression. The compound is studied by means of synchrotron-based powder x-ray diffraction (XRD) and optical-absorption techniques. The occurrence of a non-reversible phase transition is detected. The transition is from the zircon structure to the fergusonite-type structure and takes place around 6 GPa with nearly 10% volume discontinuity. XRD measurements on the pressure cycled sample confirm for the first time that the fergusonite-type ScVO4 can be recovered as the metastable phase at ambient conditions. Raman spectroscopic measurements verify the metastable phase to be of a fergusonite-type phase. Theoretical calculations also corroborate the experimental findings. The fergusonite phase is found to be stiffer than the ambient-pressure zircon phase, as indicated by the observed experimental and theoretical bulk moduli. The optical properties and lattice-dynamics calculation of the fergusonite ScVO4 are discussed. At ambient pressure the band gap of the zircon (fergusonite)-type ScVO4 is 2.75 eV (2.3 eV). This fact suggests that the novel metastable polymorph of ScVO4 can have applications in green technologies; for instance, it can be used as photocatalytic material for hydrogen production by water splitting.

14.
J Phys Condens Matter ; 28(3): 035402, 2016 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-26733093

RESUMEN

The compression behavior of zircon-type samarium orthovanadate, SmVO4, has been investigated using synchrotron-based powder x-ray diffraction and ab initio calculations of up to 21 GPa. The results indicate the instability of ambient zircon phase at around 6 GPa, which transforms to a high-density scheelite-type phase. The high-pressure phase remains stable up to 21 GPa, the highest pressure reached in the present investigations. On pressure release, the scheelite phase is recovered. The crystal structure of the high-pressure phase and the equations of state for the zircon- and scheelite-type phases have been determined. Various compressibilities, such as the bulk, axial and bond compressibilities, estimated from the experimental data are found to be in good agreement with the results obtained from theoretical calculations. The calculated elastic constants show that the zircon structure becomes mechanically unstable beyond the transition pressure. Overall there is good agreement between the experimental and theoretical findings.

15.
Neonatology ; 109(3): 186-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26780534

RESUMEN

Probiotics for preterm infants have been shown to reduce the incidence of necrotising enterocolitis and all-cause mortality in a recent meta-analysis. It has been argued, however, that some of these results may not be applicable to specific subgroups, e.g. infants with a birth weight of <1,000 g. The specific role of probiotics in improving health outcomes in preterm and term infants following intestinal surgery is not well defined. We report a case of a premature infant diagnosed with late-onset sepsis due to Lactobacillus rhamnosus following a laparotomy. We review pertinent published cases. This case highlights the importance of considering preterm infants as being at a higher risk of systemic probiotic infection following intestinal surgery.


Asunto(s)
Enfermedades del Prematuro/etiología , Lactobacillus/patogenicidad , Laparotomía/efectos adversos , Probióticos/efectos adversos , Sepsis/microbiología , Humanos , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/dietoterapia , Lactobacillus/aislamiento & purificación , Masculino , Complicaciones Posoperatorias/microbiología , Sepsis/etiología
16.
Phys Chem Chem Phys ; 17(48): 32204-10, 2015 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-26577027

RESUMEN

(p-Chloroanilinium)2CuCl4(C2H14Cl6CuN2) is from an important family of organic-inorganic layered hybrid compounds which can be a possible candidate for multiferroicity. In situ high pressure FTIR, Raman and resistivity measurements on this compound indicate the weakening of Jahn-Teller distortion and the consequent removal of puckering of the CuCl6(4-) octahedra within the layer. These effects trigger insulator to semiconductor phase transition along with a change in the sample colour from yellow to dark red. This article explains the crucial role of the anisotropic volume reduction of the CuCl6(4-) octahedron (caused due to the quenching of Jahn-Teller distortion) in the observed insulator to semiconductor phase transition.

18.
J Phys Condens Matter ; 26(26): 265402, 2014 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-24912596

RESUMEN

We report a high-pressure experimental and theoretical investigation of the structural properties of zircon-type HoVO4. Angle-dispersive x-ray diffraction measurements were carried out under quasi-hydrostatic and partial non-hydrostatic conditions up to 28 and 23.7 GPa, respectively. In the first case, an irreversible phase transition is found at 8.2 GPa. In the second case, the onset of the transition is detected at 4.5 GPa, a second (reversible) transition is found at 20.4 GPa, and a partial decomposition of HoVO4 was observed. The structures of the different phases have been assigned and their equations of state (EOS) determined. Experimental results have also been compared to theoretical calculations which fully agree with quasi-hydrostatic experiments. Theory also suggests the possibility of another phase transition at 32 GPa; i.e. beyond the pressure limit covered by present experiments. Furthermore, calculations show that deviatoric stresses could trigger the transition found at 20.4 GPa under non-hydrostatic conditions. The reliability of the present experimental and theoretical results is supported by the consistency between the values yielded for transition pressures and EOS parameters by the two methods.

19.
Burns ; 37(7): 1150-3, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21764219

RESUMEN

Many references exist in the literature identifying the usefulness of oxandrolone in treating muscle wasting due to various conditions including severe burns. However, there is an absence of dosage form alternatives as it is only available as tablets. The dose for children is weight based (0.1 mg/kg) which is difficult to achieve with the currently available tablets of 2.5 mg and 10 mg. The literature provides ample evidence of clinical importance but little guidance on extemporaneous oral liquid formulation of oxandrolone. In order to develop and validate an extemporaneous liquid formulation, suspensions of oxandrolone were developed using locally available (New Zealand) vehicles. Combinations of these vehicles with ethanol, as advised in some articles were also tried. Assay method was developed for oxandrolone using High Performance Liquid Chromatography (HPLC) and Mass Spectroscopy (LC-MS). The formulations were evaluated for stability as per the International Conference on Harmonization (ICH) stability guidelines. They were observed for physical and chemical stability at different time points over a period of 28 days. A stable and validated liquid formulation of oxandrolone has been developed which can be made under the hospital and community pharmacy conditions. The formula utilises commercially available oxandrolone tablets, crushed and dispersed in Simple Syrup BP or Orablend(®) vehicle. The formulation has confirmed stability for 21 days and can be easily made with locally available vehicles.


Asunto(s)
Oxandrolona/química , Administración Oral , Cromatografía Líquida de Alta Presión , Composición de Medicamentos , Estabilidad de Medicamentos , Oxandrolona/administración & dosificación , Oxandrolona/análisis , Soluciones Farmacéuticas/química , Vehículos Farmacéuticos/química
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