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1.
Nurse Educ Today ; 121: 105702, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36577288

RESUMO

BACKGROUND: The transition experience of newly graduated registered nurses is highly stressful and associated with high attrition rates. OBJECTIVES AND DESIGN: This qualitative systematic review aims to consolidate the available evidence on the experiences of newly graduated registered nurses' role transition from nursing students to registered nurses. DATA SOURCES: English language research published between 2010 and 2022 was searched using PubMed, CINAHL, Scopus, Embase, PsycInfo and ProQuest Dissertations and Thesis databases. REVIEW METHODS: Data were extracted using a data extraction form and appraised using the Critical Appraisal Skills Programme (CASP) tool for published studies or the Authority, Accuracy, Coverage, Objectivity, Date, Significance checklist for unpublished studies or grey literature, respectively. RESULTS: The review included 25 studies and the meta-synthesis identified four themes: (a) Knowledge deficit, (b) Overwhelming clinical practise, (c) Importance of workplace support, and (d) Meaning of "being a nurse". CONCLUSIONS: Newly graduated registered nurses experienced facing knowledge deficits in the clinical setting and felt overwhelmed with work, especially for newly graduated registered nurses during the Covid-19 pandemic. Support from colleagues was invaluable, and they wished for better support through standardised transition programs. Despite nursing being mentally and physically exhausting, many newly graduated registered nurses regarded their profession satisfying and meaningful, however some eventually resigned. Understanding the transition experiences of newly graduated registered nurses can provide valuable insights on how to facilitate their transition and in turn decrease attrition rates, and ensure safe care for the patients and that public healthcare needs are met.


Assuntos
COVID-19 , Enfermeiras e Enfermeiros , Estudantes de Enfermagem , Humanos , Pesquisa Qualitativa , Pandemias , Papel do Profissional de Enfermagem
2.
J Control Release ; 203: 161-9, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25701612

RESUMO

The ultimate aim of this study was to develop asulacrine (ASL)-loaded long-circulating liposomes to prevent phlebitis during intravenous (i.v.) infusion for chemotherapy. Poly(ethylene)glycol (PEG) and poloxamer 188-modified liposomes (ASL-PEGL and ASL-P188L) were developed, and ASL was loaded using a remote loading method facilitated with a low concentration of sulfobutyl ether-ß-cyclodextrin as a drug solubilizer. The liposomes were characterized in terms of morphology, size, release properties and stability. Pharmacokinetics and venous tissue tolerance of the formulations were simultaneously studied in rabbits following one-hour i.v. infusion via the ear vein. The irritancy was assessed using a rat paw-lift/lick model after subplantar injections. High drug loading 9.0% w/w was achieved with no drug leakage found from ASL-PEGL or ASL-P188L suspended in a 5% glucose solution at 30days. However, a rapid release (leakage) from ASL-PEGL was observed when PBS was used as release medium, partially related to the use of cyclodextrin in drug loading. Post-insertion of poloxamer 188 to the liposomes appeared to be able to restore the drug retention possibly by increasing the packing density of phospholipids in the membrane. In rabbits (n=5), ASL-P188L had a prolonged half-life with no drug precipitation or inflammation in the rabbit ear vein in contrast to ASL solution. Following subplantar (footpad) injections in rats ASL solution induced paw-lick/lift responses in all rats whereas ASL-P188L caused no response (n=8). PEGylation showed less benefit possibly due to the drug 'leakage'. In conclusion, drug precipitation in the vein and the drug mild irritancy may both contribute to the occurrence of phlebitis caused by the ASL solution, and could both be prevented by encapsulation of the drug in liposomes. Poloxamer 188 appeared to be able to 'seal' the liposomal membrane and enhance drug retention. The study also highlighted the importance of bio-relevant in vitro release study in formulation screening.


Assuntos
Amsacrina/análogos & derivados , Antineoplásicos/administração & dosagem , Bombas de Infusão/efeitos adversos , Lipossomos/química , Flebite/etiologia , Poloxâmero/química , Polietilenoglicóis/química , Amsacrina/administração & dosagem , Amsacrina/efeitos adversos , Amsacrina/farmacocinética , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Precipitação Química , Injeções/efeitos adversos , Masculino , Flebite/induzido quimicamente , Flebite/prevenção & controle , Coelhos , Ratos Sprague-Dawley
3.
Pharm Res ; 32(4): 1451-61, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25355460

RESUMO

PURPOSE: To develop a liposomal system with high drug loading (DL) for intravenous (i.v.) delivery of a poorly water-soluble basic drug, asulacrine (ASL). METHODS: A thin-film hydration and extrusion method was used to fabricate the PEGylated liposomal membranes followed by a freeze and thaw process. A novel active drug loading method was developed using ammonium sulphate gradient as an influx driving force of ASL solubilized with sulfobutyl ether-ß-cyclodextrin (SBE-ß-CD). DL was maximized by optimizing liposomal preparation and loading conditions. Pharmacokinetics was evaluated following i.v. infusion in rabbits. RESULTS: Freeze-thaw resulted in unilamellar liposome formation (180 nm) free of micelles. Higher DL was obtained when dialysis was used to remove the untrapped ammonium sulphate compared to ultracentrifuge. The pH and SBE-ß-CD level in the loading solution played key roles in enhancing DL. High DL ASL-liposomes (8.9%w/w, drug-to-lipid mole ratio 26%) were obtained with some drug "bundles" in the liposomal cores and were stable in a 5% glucose solution for >80 days with minimal leakage (<2%). Surprisingly, following administration of ASL-liposomes prepared with or without SBE-ß-CD, the half-lives were similar to the drug solution despite an increased area under the curve, indicating drug leakage from the carriers. CONCLUSIONS: High liposomal DL was achieved with multiple strategies for a poorly-water soluble weak base. However, the liposomal permeability needed to be tailored to improve drug retention.


Assuntos
Sulfato de Amônio/química , Amsacrina/análogos & derivados , Antineoplásicos/química , Portadores de Fármacos/química , Tecnologia Farmacêutica/métodos , beta-Ciclodextrinas/química , Amsacrina/administração & dosagem , Amsacrina/química , Amsacrina/farmacocinética , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Infusões Intravenosas , Lipossomos , Estrutura Molecular , Coelhos , Solubilidade
4.
Int J Pharm ; 473(1-2): 528-35, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25079434

RESUMO

To facilitate the development of a liposomal formulation for cancer therapy, the physicochemical properties of asulacrine (ASL), an anticancer drug candidate, were characterized. Nano-liposomes were prepared by thin-film hydration in conjugation with active drug loading using ammonium sulphate and post-insertion with Poloxamer 188. A stability-indicating HPLC assay with diode array detection was developed for the determination of ASL concentrations. The U-shaped pH-solubility profile in aqueous solutions, with a lowest solubility at pH 7.4 (0.843 µg/mL), indicated that ASL is an ampholyte, and dilution or neutralization of acidic drug solutions used in clinical trials with physiological fluids may cause drug precipitation. The basic pKa value measured by absorbance spectroscopy was 6.72. The logD value at pH 3.8 was 1.15 which increased to 3.24 as pH increased to 7.4. ASL was found to be the most stable in acidic conditions and degraded most rapidly in alkaline conditions. An extra-liposomal pH of 5.6 during drug loading was found to be optimal to achieve the highest drug loading (DL) of 4.76% and entrapment efficiency (EE) of 99.9%. At this pH, >90% of ASL was ionized conferring high drug solubility (1mg/mL) and acted as a reservoir of unionized ASL to be transported into liposomal cores. As a suspension the optimized liposomes showed great physicochemical stability for five months at 4°C. In summary, the obtained physicochemical parameters provided insightful information useful to maximise DL into the liposomes, and explain a tendency of drug precipitation of pH-solubilized formulations following intravenous infusion.


Assuntos
Amsacrina/análogos & derivados , Antineoplásicos/química , Amsacrina/química , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Lipossomos , Solubilidade
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