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This work describes the development of a robust and repeatable in vitro 3D culture model of glial scarring, which may be used to evaluate the foreign body response to electrodes and other implants in the central nervous system. The model is based on methacrylated hyaluronic acid, a hydrogel that may be photopolymerized to form an insoluble network. Hydrogel scaffolds were formed at four different macromer concentrations (0.50, 0.75, 1.00, and 1.50% (w/v)). As expected, the elastic modulus of the scaffolds increased with increasing macromer weight fraction. Adult rat brain tested under identical conditions had an elastic modulus range that spanned the elastic modulus of both the 0.50 and 0.75% (w/v) hydrogel samples. Gels formed with higher macromer weight fraction had decreased equilibrium swelling ratio and visibly thicker pore walls relative to gels formed with lower macromer weight fractions. Mixed glial cells (microglia and astrocytes) were then encapsulated in the HA scaffolds. Viability of the mixed cultures was most stable at a cell density of 1 × 10(7) cells/mL. Cell viability at the highest macromer weight fraction tested (1.50% (w/v)) was significantly lower than other tested gels (0.50, 0.75 and 1.00% (w/v)). The inflammatory response of microglia and astrocytes to a microelectrode inserted into the scaffold was assessed over a period of 2 weeks and closely represented that reported in vivo. Microglia responded first to the electrode (increased cell density at the electrode, and activated morphology) followed by astrocytes (appeared to line the electrode in a manner similar to glial scarring). All together, these results demonstrate the potential of the 3D in vitro model system to assess glial scarring in a robust and repeatable manner.
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Materiais Biocompatíveis/química , Técnicas de Cultura de Células/métodos , Ácido Hialurônico/química , Animais , Animais Recém-Nascidos , Astrócitos/efeitos dos fármacos , Astrócitos/fisiologia , Materiais Biocompatíveis/farmacologia , Eletrodos/normas , Ácido Hialurônico/farmacologia , Neuroglia/efeitos dos fármacos , Neuroglia/fisiologia , Ratos , Ratos Sprague-DawleyRESUMO
The UK regulatory body for registered veterinary nurses (RVNs), the Royal College of Veterinary Surgeons (RCVS), maintains the professional register of RVNs. Every year, a proportion fail to re-join the register. This research aimed to identify the factors that predict retention and to make recommendations to inform the Royal College of Veterinary Surgeons as the regulator as well as both the veterinary nursing and veterinary professions. An analysis of the raw quantitative data generated by the 2014 and 2019 RCVS surveys of the veterinary nurse profession was undertaken using multivariable logistic regression analysis. First, bivariable associations were estimated using unadjusted odds ratios to explore whether there are any (unconditional) associations between each predictor and the outcome. Predictors that were significant unconditional predictors of intention to leave were then entered into a multivariable logistic regression, yielding adjusted odds ratios. Quantitative analysis found significant relationships between intention to leave and the following factors in both the 2014 and 2019 survey data: job satisfaction; believing that veterinary nursing offers good opportunities for career progression; satisfaction with employer support; and having a second job. The following factors were significant in 2014, but not in 2019: undertaking nurse clinics, feeling valued, and being respected by veterinary surgeons. The factors that influence the retention of registered veterinary nurses (RVNs) within the profession are multifactorial and individual. Nurses are responsible for ensuring that those they work with are aware of their skill set and that they themselves are accountable for utilisation of those skills. When veterinary nurses are supported by their employers, they are more likely to stay in the profession. Having a clearly defined career structure and mapped routes for progression will be helpful with retention. A sense of job satisfaction was another important factor in retention. A pay structure linked to a career pathway framework, such as in human-centred nursing, is an area for further work.
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BACKGROUND: The popularity of brachycephalic dogs continues to increase despite inherent breed health problems. Increased education of current and potential brachycephalic dog owners could reduce the desirability of severely affected dogs. METHODS: Members of the general public were prospectively recruited to assess their understanding and opinions of brachycephalic breed-related health problems, before and after an educational intervention on brachycephalic obstructive airway syndrome (BOAS). RESULTS: A total of 587 people participated. Before the intervention most participants considered characteristics of BOAS to be normal for brachycephalic dogs. Following the intervention this was moderately reduced. Responses highlighted that defining 'normal' for a breed is difficult. Referring to a trait as 'normal', even in a negative context results in normalisation. 99.7% of participants had an improved understanding of BOAS following the intervention. However, only 53.0% of the total participants and 29.3% of brachycephalic dog owning participants had their opinion of brachycephalic dogs changed. 99.5% of participants believed that potential owners should be more aware of BOAS and 57.3% of brachycephalic dog owners would have liked further information about breed health problems before purchasing their dog. CONCLUSION: Educational interventions may be beneficial in improving understanding and awareness of BOAS however, normalisation of clinical signs of BOAS remains prevalent.
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Obstrução das Vias Respiratórias , Craniossinostoses , Doenças do Cão , Obstrução das Vias Respiratórias/veterinária , Animais , Cruzamento , Craniossinostoses/veterinária , Doenças do Cão/diagnóstico , Cães , Humanos , Opinião Pública , SíndromeRESUMO
Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic condition characterized by pelvic pain coupled with urinary frequency and urgency. The underlying cause of IC/BPS is unknown; there is no cure. Dietary components exacerbate symptoms. The Anti-Inflammatory Diet for Interstitial Cystitis (AID-IC) employs a randomized, crossover design to evaluate the effect of a plant-based, low saturated fat diet on the quality of life of women with IC/BPS. Insights on the implementation of the protocol and reflections on the facilitators and barriers experienced during the pilot study follow. The logistics of the protocol proved time-consuming; however, the barriers were surmountable. Quantitative and qualitative findings suggest that the AID-IC therapeutic diet may have lessened symptoms and improved the quality of life for many of the women in the study.
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OBJECTIVES: To compare physical activity and length and quality of sleep between brachycephalic dogs and a control population. METHODS: Brachycephalic and control dogs were prospectively enrolled. Length of activity and sleep were determined via accelerometer use. Owners completed a questionnaire regarding typical daily activity, sleep patterns and an 'owner reported breathing score (ORBS)'. One hour of normal home sleep was recorded for each dog, and a veterinary observer subjectively scored the dogs' sleep quality. RESULTS: Twenty brachycephalic and 15 control dogs were included. There were no differences between age and weight. Owners reported brachycephalic dogs to be less active (p = 0.022) and have higher ORBS (p < 0.001) compared to control dogs. Brachycephalic dogs had increased sleep disturbances compared to control dogs (p = 0.001), and video sleep score was positively correlated with increased sleep disturbances (r2 = 0.47, p = 0.007). There were no differences in active and sleep times based on accelerometry between groups. CONCLUSION: Brachycephalic dogs have more disturbed sleep, which may have negative implications on welfare, but there were no differences in activity or length of sleep between groups. There is evidence that signs suggestive of brachycephalic obstructive airway syndrome (BOAS) as assessed by ORBS is correlated with poorer sleep quality, indicating that reduced sleep quality is part of BOAS. Owners may underestimate disturbed sleep or may perceive disturbed sleep to be normal.
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Obstrução das Vias Respiratórias , Craniossinostoses , Doenças do Cão , Acelerometria/veterinária , Obstrução das Vias Respiratórias/veterinária , Animais , Craniossinostoses/veterinária , Cães , Projetos Piloto , Qualidade do SonoRESUMO
Enabling gene expression in skin fibroblasts using safe, nonviral gene delivery has the potential to stimulate wound healing and aid in skin tissue engineering efforts. In this study, several lipid-substituted poly(L-Lysines) (PLL) were investigated for their ability to deliver a plasmid DNA (pEGFP) to human skin fibroblasts. While native and lipid-substituted PLLs showed complete complexation with pEGFP, polymers with higher lipid substitution were more resilient to dissociation after heparin treatment. All polymers showed good protection of pEGFP against DNase I and DNase II digestion in vitro. DNA delivery studies using fluorescently labeled pEGFP showed that native PLL lacked the ability to deliver pEGFP into cells, whereas most of the lipid-substituted PLLs gave efficient pEGFP delivery into the cells. Extent of lipid substitution was an important factor in DNA delivery efficiency. The intracellular pEGFP was intact after delivery with lipid-substituted polymers up to 7 days. An RT-PCR methodology indicated successful transcription of the reporter GFP gene, which was not the case when the cells were transfected with a blank plasmid containing no functional GFP gene. Further studies with flow cytometry showed that successful protein expression was obtained with PLLs substituted with myristic and stearic acid, the latter displaying a relatively lower toxicity. We conclude that substituting lipids on PLL results in effective gene carriers and the extent of substitution, rather than the individual lipid, appeared to be critical for effective plasmid delivery.
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Fibroblastos/metabolismo , Lipídeos/química , Polilisina/química , Pele/metabolismo , Transfecção , Fragmentação do DNA , Desoxirribonucleases/metabolismo , Eletroforese em Gel de Ágar , Citometria de Fluxo , Perfilação da Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Microscopia de Fluorescência , Ácido Mirístico/química , Plasmídeos/metabolismo , Polilisina/síntese química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ácidos Esteáricos/químicaRESUMO
In the central nervous system, numerous acute injuries and neurodegenerative disorders, as well as implanted devices or biomaterials engineered to enhance function result in the same outcome: excess inflammation leads to gliosis, cytotoxicity, and/or formation of a glial scar that collectively exacerbate injury or prevent healthy recovery. With the intent of creating a system to model glial scar formation and study inflammatory processes, we have generated a 3D cell scaffold capable of housing primary cultured glial cells: microglia that regulate the foreign body response and initiate the inflammatory event, astrocytes that respond to form a fibrous scar, and oligodendrocytes that are typically vulnerable to inflammatory injury. The present work provides a detailed step-by-step method for the fabrication, culture, and microscopic characterization of a hyaluronic acid-based 3D hydrogel scaffold with encapsulated rat brain-derived glial cells. Further, protocols for characterization of cell encapsulation and the hydrogel scaffold by confocal immunofluorescence and scanning electron microscopy are demonstrated, as well as the capacity to modify the scaffold with bioactive substrates, with incorporation of a commercial basal lamina mixture to improved cell integration.
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Hidrogel de Polietilenoglicol-Dimetacrilato , Inflamação/patologia , Neuroglia/patologia , Animais , Células Cultivadas , Ácido Hialurônico/química , Oligodendroglia/patologia , Ratos , Ratos Sprague-DawleyRESUMO
We show full Li/S cells with the use of balanced and high capacity electrodes to address high power electro-mobile applications. The anode is made of an assembly comprising of silicon nanowires as active material densely and conformally grown on a 3D carbon mesh as a light-weight current collector, offering extremely high areal capacity for reversible Li storage of up to 9 mAh/cm(2). The dense growth is guaranteed by a versatile Au precursor developed for homogenous Au layer deposition on 3D substrates. In contrast to metallic Li, the presented system exhibits superior characteristics as an anode in Li/S batteries such as safe operation, long cycle life and easy handling. These anodes are combined with high area density S/C composite cathodes into a Li/S full-cell with an ether- and lithium triflate-based electrolyte for high ionic conductivity. The result is a highly cyclable full-cell with an areal capacity of 2.3 mAh/cm(2), a cyclability surpassing 450 cycles and capacity retention of 80% after 150 cycles (capacity loss <0.4% per cycle). A detailed physical and electrochemical investigation of the SiNW Li/S full-cell including in-operando synchrotron X-ray diffraction measurements reveals that the lower degradation is due to a lower self-reduction of polysulfides after continuous charging/discharging.