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1.
BMC Med Educ ; 22(1): 17, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983477

RESUMO

BACKGROUND: Despite considerable efforts there continues to be a degree awarding gap within the United Kingdom (UK) between the proportion of White British students receiving higher classifications, compared to ethnic minority UK-domiciled students. Practice placement elements constitute approximately 50% of most health and social care programmes, yet surprisingly little research exists related to the factors which may contribute to ethnic minority student placement outcomes or experiences. This study bridges this evidence gap by exploring factors influencing differential placement outcomes of ethnic minority students from the perspectives of key stakeholders. METHODS: The study followed a descriptive qualitative research design and was multi-disciplinary, with participants drawn from across nursing, midwifery, social work and the allied health professions. Participants from four stakeholder categories (ethnic minority students, academic staff, placement educators and student union advisors) were invited to join separate focus groups. Focus groups were recorded and transcribed and analysed thematically. RESULTS: Ten separate focus groups [n = 66] yielded three primary themes: 1) recognition, which highlighted stakeholder perceptions of the issues [sub-themes: acknowledging concerns; cultural norms; challenging environments]; 2) the lived experience, which primarily captured ethnic minority student perspectives [sub-themes: problematising language and stereotyping, and being treated differently]; 3) surviving not thriving, which outlines the consequences of the lived experience [sub-themes: withdrawing mentally, feeling like an alien]. CONCLUSION: This study presents a rich exploration of the factors affecting differential outcomes of ethnic minority students on practice placements through the lens of four different stakeholder groups. To our knowledge this is the first study in which this comprehensive approach has been taken to enable multiple viewpoints to be accessed across a wide range of health and social care professions. The issues and challenges raised appear to be common to most if not all of these disciplines. This study highlights the urgent need to value and support our ethnic minority students to remove the barriers they face in their practice learning settings. This is a monumental challenge and requires both individuals and organisations to step up and take collective responsibility.


Assuntos
Minorias Étnicas e Raciais , Etnicidade , Humanos , Grupos Minoritários , Pesquisa Qualitativa , Apoio Social , Estudantes
2.
Scand J Occup Ther ; 29(1): 33-45, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33427535

RESUMO

Background: Numbers of international students enrolling on occupational therapy (OT) courses in Western institutions have increased. Previous examination of these students' experience of practice education is limited.Objective: To explore the opportunities and challenges experienced by international students in OT practice education.Methods: This study adopted a phenomenological approach, recruiting six individuals from three UK universities. Data from semi-structured interviews was given thematic analysis for result interpretation.Results: Participants identified learning OT in the workplace, working in a multidisciplinary team and personal and professional development as practice education opportunities. Language difficulties, differences in communication styles, multiple cultural differences and unfamiliarity with the National Health Service (NHS) were the main challenges. Good practice educators and supportive team members were the main contributors to positive placement experiences.Conclusions: Participants gained knowledge and skills from practice education that existing healthcare literature suggests they are expected to attain. Several challenges were highlighted regarding participation in practice education. The findings reveal a need to enhance practice educators' skills in supervising international students. Universities are recommended to invest time and resources in supporting the learning needs of these students.Significance: The first study to present international students views on OT pre-registration practice placements in the UK.


Assuntos
Terapia Ocupacional , Humanos , Aprendizagem , Medicina Estatal , Estudantes , Reino Unido
3.
Life (Basel) ; 12(2)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35207484

RESUMO

BACKGROUND: This study aimed to identify the better arc configuration of volumetric modulated arc therapy (VMAT) for high-grade glioma and glioblastoma, focusing on a dose reduction to the hypothalamic-pituitary axis through an analysis of dose-volumetric parameters, as well as a correlation analysis between the planned target volume (PTV) to organs at risk (OAR) distance and the radiation dose. METHOD: Twenty-four patients with 9 high-grade glioma and 15 glioblastomas were included in this study. Identical CT, MRI and structure sets of each patient were used for coplanar VMAT (CO-VMAT), dual planar VMAT (DP-VMAT) and multi-planar VMAT (MP-VMAT) planning. The dose constraints adhered to the RTOG0825 and RTOG9006 protocols. The dose-volumetric parameters of each plan were collected for statistical analysis. Correlation analyses were performed between radiation dose and PTV-OARs distance. RESULTS: The DP-VMAT and MP-VMAT achieved a significant dose reduction to most nearby OARs when compared to CO-VMAT, without compromising the dose to PTV, plan homogeneity and conformity. For centrally located OARs, including the hypothalamus, pituitary, brain stem and optic chiasm, the dose reductions ranged from 2.65 Gy to 3.91 Gy (p < 0.001) in DP-VMAT and from 2.57 Gy to 4 Gy (p < 0.001) in MP-VMAT. Similar dose reduction effects were achieved for contralaterally located OARs, including the hippocampus, optic nerve, lens and retina, ranging from 1.06 Gy to 4.37 Gy in DP-VMAT and from 0.54 Gy to 3.39 Gy in MP-VMAT. For ipsilaterally located OARs, DP-VMAT achieved a significant dose reduction of 1.75 Gy to Dmax for the optic nerve. In the correlation analysis, DP-VMAT and MP-VMAT showed significant dose reductions to centrally located OARs when the PTV-OAR distance was less than 4 cm. In particular, DP-VMAT offered better sparing to the optic chiasm when it was located less than 2 cm from the PTV than that of MP-VMAT and CO-VMAT. DP-VMAT and MP-VMAT also showed better sparing to the contralateral hippocampus and retina when they were located 3-8 cm from the PTV. CONCLUSION: The proposed DP-VMAT and MP-VMAT demonstrated significant dose reductions to centrally located and contralateral OARs and maintained the high plan qualities to PTV with good homogeneity and conformity when compared to CO-VMAT for high-grade glioma and glioblastoma. The benefit in choosing DP-VMAT and MP-VMAT over CO-VMAT was substantial when the PTV was located near the hypothalamus, pituitary, optic chiasm, contralateral hippocampus and contralateral retina.

4.
J Biol Chem ; 285(6): 3986-3996, 2010 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-19940120

RESUMO

The stigmatic estolide is a lipid-based polyester constituting the major component of exudate in solanaceous plants. Although the exudate is believed to play important roles in the pollination process, the biosynthetic pathway of stigmatic estolide, including genes encoding the key enzymes, remains unknown. Here we report the cloning and characterization of the cytochrome P450 gene CYP86A22, which encodes a fatty acyl-CoA omega-hydroxylase involved in estolide biosynthesis in the stigma of Petunia hybrida. A CYP86A22 cDNA was isolated from a developing stigma cDNA library, and the corresponding gene was shown to express predominantly in the developing stigma. Among six P450 genes isolated from this library, only CYP86A22 was implicated in omega-hydroxylation following RNA interference (RNAi)-mediated suppression. Unlike wild-type plants in which omega-hydroxy fatty acids (mainly in the form of 18-hydroxy oleic acid and 18-hydroxy linoleic acid) compose 96% of total stigma fatty acids, the omega-hydroxy fatty acids were essentially absent in the stigmas from 18 of 46 CYP86A22-RNAi transgenic plants and had varying levels of suppression in the remaining 28 plants. Furthermore, lipids in the 18 CYP86A22-RNAi stigmas were predominantly triacylglycerols and diacylglycerols instead of the estolides, which characterize the wild-type stigma. Analyses of recombinant CYP86A22 conclusively demonstrated that this P450 is a omega-hydroxylase with a substrate preference for both saturated and unsaturated acyl-CoAs rather than free fatty acids. We conclude that the cytochrome P450 enzyme CYP86A22 is the key fatty acyl-CoA omega-hydroxylase essential for the production of omega-hydroxy fatty acids and the biosynthesis of triacylglycerol-/diacylglycerol-based estolide polyesters in the petunia stigma.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Flores/genética , Petunia/genética , Proteínas de Plantas/genética , Poliésteres/metabolismo , Acil Coenzima A/metabolismo , Sequência de Aminoácidos , Northern Blotting , Clonagem Molecular , Citocromo P-450 CYP4A/genética , Citocromo P-450 CYP4A/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , DNA Complementar/química , DNA Complementar/genética , Ácidos Graxos/metabolismo , Flores/crescimento & desenvolvimento , Flores/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Lipídeos/química , Dados de Sequência Molecular , Petunia/crescimento & desenvolvimento , Petunia/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Poliésteres/química , RNA Interferente Pequeno/genética , Análise de Sequência de DNA , Especificidade por Substrato
5.
Nat Commun ; 12(1): 5220, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471104

RESUMO

Advancement in human induced pluripotent stem cell (iPSC) neuron and microglial differentiation protocols allow for disease modeling using physiologically relevant cells. However, iPSC differentiation and culturing protocols have posed challenges to maintaining consistency. Here, we generated an automated, consistent, and long-term culturing platform of human iPSC neurons, astrocytes, and microglia. Using this platform we generated a iPSC AD model using human derived cells, which showed signs of Aß plaques, dystrophic neurites around plaques, synapse loss, dendrite retraction, axon fragmentation, phospho-Tau induction, and neuronal cell death in one model. We showed that the human iPSC microglia internalized and compacted Aß to generate and surround the plaques, thereby conferring some neuroprotection. We investigated the mechanism of action of anti-Aß antibodies protection and found that they protected neurons from these pathologies and were most effective before pTau induction. Taken together, these results suggest that this model can facilitate target discovery and drug development efforts.


Assuntos
Doença de Alzheimer/metabolismo , Astrócitos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Microglia/metabolismo , Neurônios/metabolismo , Diferenciação Celular , Humanos , Cinética , Placa Amiloide , Sinapses/metabolismo
6.
ACS Appl Mater Interfaces ; 13(26): 30326-30336, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34162211

RESUMO

Plasmid DNA (pDNA) nanoparticles synthesized by complexation with linear polyethylenimine (lPEI) are one of the most effective non-viral gene delivery vehicles. However, the lack of scalable and reproducible production methods and the high toxicity have hindered their clinical translation. Previously, we have developed a scalable flash nanocomplexation (FNC) technique to formulate pDNA/lPEI nanoparticles using a continuous flow process. Here, we report a tangential flow filtration (TFF)-based scalable purification method to reduce the uncomplexed lPEI concentration in the nanoparticle formulation and improve its biocompatibility. The optimized procedures achieved a 60% reduction of the uncomplexed lPEI with preservation of the nanoparticle size and morphology. Both in vitro and in vivo studies showed that the purified nanoparticles significantly reduced toxicity while maintaining transfection efficiency. TFF also allows for gradual exchange of solvents to isotonic solutions and further concentrating the nanoparticles for injection. Combining FNC production and TFF purification, we validated the purified pDNA/lPEI nanoparticles for future clinical translation of this gene nanomedicine.


Assuntos
DNA/isolamento & purificação , Filtração/métodos , Nanopartículas/química , Plasmídeos/isolamento & purificação , Animais , DNA/química , Feminino , Técnicas de Transferência de Genes , Humanos , Camundongos Endogâmicos BALB C , Células PC-3 , Plasmídeos/química , Polietilenoimina/química
7.
Biotechnol Prog ; 33(6): 1579-1588, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28649725

RESUMO

Transient gene expression in mammalian cells is an efficient process for producing recombinant proteins for various research applications to support large molecule therapeutics development. For the first time, we report a high throughput small molecule (SM) screen to identify novel compounds that increase antibody titers after polyethylenimine (PEI) transient transfection of a HEK293 cell line. After screening 31,413 SMs in a 50 µL scaled-down process, we validated 164 SMs to improve yields by up to twofold. The titer increase mediated by the SMs varied for different antibodies. SM dose optimizations resulted in almost threefold higher titers. The top 2, structurally distinct SM hits, increased antibody titers more than twofold in a 1 mL production process. Averaged across three antibodies of different expression levels, the compounds enhanced transient productivity by ∼80%. Intriguingly, both compounds arrested cells in the G2/M cell cycle phase leading to a decrease in growth and nutrient consumption, while elevating titer, nuclear plasmid DNA (pDNA) copy numbers, and mRNA levels. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 3:1579-1588, 2017.


Assuntos
Formação de Anticorpos/genética , Ensaios de Triagem em Larga Escala , Imunoglobulina G/biossíntese , Proteínas Recombinantes/biossíntese , Animais , Anticorpos/genética , Anticorpos/imunologia , Formação de Anticorpos/imunologia , Células CHO , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Células HEK293 , Humanos , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Polietilenoimina/farmacologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Bibliotecas de Moléculas Pequenas/farmacologia , Transfecção
8.
ACS Biomater Sci Eng ; 1(6): 448-455, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29399627

RESUMO

Nanoparticles formed through complexation of plasmid DNA and copolymers are promising gene-delivery vectors, offering a wide range of advantages over alternative delivery strategies. Notably, recent research has shown that the shape of these particles can be tuned, which makes it possible to gain understanding of their shape-dependent transfection properties. Whereas earlier methods achieved shape tuning through the use of block copolymers and variation of solvent polarity, here we demonstrate through a combined experimental and computational approach that the same degree of shape control can be achieved through the use of graft copolymers that are easier to synthesize and provide a wider range of parameters for shape control. Moreover, the approach presented here does not require the use of organic solvents. The simulation work provides insight into the mechanism governing the shape variation as well as an effective model to guide further design of non-viral gene-delivery vectors. Our experimental findings offer important opportunities for the facile and large-scale synthesis of biocompatible gene-delivery vectors with well-controlled shape and tunable transfection properties. The in vitro study shows that both micelle shape and transfection efficiency are strongly correlated with the key structural parameters of the graft copolymer carriers.

9.
J Biotechnol ; 112(3): 247-53, 2004 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-15313002

RESUMO

Although the expression of histidine (His)-tagged proteins in bacteria is routine, few His-tagged proteins have been expressed in plants, and no His-tagged proteins from bacterial pathogens have been expressed in plants, to our knowledge. Here, we demonstrate expression of the Shigella flexneri invasion plasmid antigen, IpaC, in Arabidopsis thaliana. S. flexneri is the causitive trigger for bacillary dysentery, and IpaC is essential for bacterial entry into epithelial cells. IpaC, attached to a 5' leader containing six tandem His codons, was cloned into a pBI121 vector. This clone was introduced into Agrobacterium tumefaciens and Arabidopsis plants were then transformed. T1 and T2 plant generations were obtained. Total plant proteins were extracted from T2 leaves; the Bradford assay was used to determine protein concentrations. A nickel-coated ELISA plate method, using both anti-His and anti-IpaC 1 degrees antibodies, was used to detect and quantify IpaC in transgenic Arabidopsis plants. Between 1.9 and 2.3 microg IpaC/mg total plant protein was obtained; this equals 0.2% of total protein, an amount comparable to other recombinant protein estimates in plants. Expressing His-tagged proteins from bacterial pathogens, in plants, is important because plant material could ultimately be fed or applied intranasally to animals that are "at risk" for infection by such bacterial pathogens, thus causing them to raise antibodies against the pathogens--functioning as a vaccine.


Assuntos
Antígenos de Bactérias/biossíntese , Antígenos de Bactérias/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Engenharia de Proteínas/métodos , Clonagem Molecular/métodos , Regulação Bacteriana da Expressão Gênica/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Histidina/metabolismo , Proteínas Recombinantes/biossíntese , Shigella/genética , Shigella/metabolismo , Transformação Genética
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