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Medicinas Complementárias
Métodos Terapéuticos y Terapias MTCI
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1.
Health Prof Educ ; 9(2): 72-81, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37886213

RESUMEN

Background: The arts and humanities form a critical part of medical education. In this study, we explore medical students' reflections following an arts and humanities experience. An intensive day and a half long program focused on music and reflection was designed for first-year students at Harvard Medical School. Methods: Students completed an evaluation of the experience with both open-ended and Likert scale questions. Data were analyzed using a mixed methods approach. Descriptive statistics were used to analyze quantitative data and inductive content analysis for qualitative data. Results: 168 first-year medical and dental students participated in the activity. Survey response rate was 73% (n =122). Quantitatively, the overall quality of the experience was assessed at a mean value of 4.86 points (SD = 0.37 points) out of a maximum of 5, with 5 being excellent. The qualitative evaluation illustrated how the arts and humanities experience encouraged students to reflect on their leadership and doctoring skills, taking a holistic approach to their medical education, and integrating the lessons of the arts and humanities into their medical practice. Conclusion: The arts and humanities program encouraged student reflection on profound questions in medicine related to empathy, vulnerability, and authenticity. This experience broadened students' perspectives regarding the relationship between medicine and the arts and humanities.

2.
Food Nutr Res ; 632019.
Artículo en Inglés | MEDLINE | ID: mdl-31807125

RESUMEN

Nicotinamide riboside (NR), a newly recognised form of vitamin B3 and a precursor to nicotinamide adenine dinucleotide (NAD+), has been demonstrated to show therapeutic potential and the possibility of becoming a drug compound in addition to its proven role in rejuvenating ageing cells in mice. However, current literature is devoid of information relating to the physicochemical characterisation of NR and its respective impact upon formulation and final product processing. Here we report physicochemical properties of NR including pKa, log P, solubility, melting point, degradation mechanics, and kinetics, with a special focus on its stability under thermal and physiologically relevant conditions. A simple and rapid HPLC method confirms a base-catalysed hydrolysis degradation of NRCl to nicotinamide and sugar in simulated gastrointestinal (GI) fluids. Given the antagonising effect of nicotinamide against NR, the presented data have a profound impact on how NRCl should be handled both during formulation and storage to prevent formation and to limit accumulation of nicotinamide. The innovative combinatorial use of 1H NMR and Differential Scanning Calorimetry (DSC) was employed to investigate thermal events during NR melting. NRCl degrades upon melting and in solution undergoes hydrolysis in a buffer and in simulated intestinal environments. The results suggest that a proper and evidence-based formulation of NRCl is vital to enable further investigation and clinical analysis of this promising and novel nutrient. Any formulation would need to promote the stability of NRCl and protect it from hostile environments to prevent the accumulation of a potentially antagonistic degradation product. With the current work, we have filled a niche but vital gap in NR literature and the data presented may prove useful in furthering the understanding, specifically the formulation and processing of NRCl.

3.
Int J Pharm ; 535(1-2): 420-427, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-29170113

RESUMEN

Medical device-associated infections present a leading global healthcare challenge, and effective strategies to prevent infections are urgently required. Herein, we present an innovative anti-adherent hydrogel copolymer as a candidate catheter coating with complementary hydrophobic drug-carrying and eluting capacities. The amphiphilic block copolymer, Poloxamer 188, was chemically-derivatized with methacryloyl moieties and copolymerized with the hydrogel monomer, 2-hydroxyethyl methacrylate. Performance of the synthesized copolymers was evaluated in terms of equilibrium swelling, surface water wettability, mechanical integrity, resistance to encrustation and bacterial adherence, and ability to control release of the loaded fluoroquinolone antibiotic, ofloxacin. The developed matrices were able to provide significant protection from fouling, with observed reductions of over 90% in both adherence of the common urinary pathogen Escherichia coli and encrusting crystalline deposits of calcium and magnesium salts relative to the commonly employed hydrogel, poly (hydroxyethyl methacrylate). Additionally, the release kinetics of a loaded hydrophobic drug could be readily tuned through facile manipulation of polymer composition. This combinatorial approach shows significant promise in the development of suitable systems for prevention of catheter-associated infections.


Asunto(s)
Incrustaciones Biológicas/prevención & control , Catéteres/microbiología , Hidrogeles/administración & dosificación , Antibacterianos/administración & dosificación , Antibacterianos/química , Materiales Biocompatibles/administración & dosificación , Materiales Biocompatibles/química , Liberación de Fármacos , Módulo de Elasticidad , Escherichia coli/efectos de los fármacos , Hidrogeles/química , Metacrilatos/química , Ofloxacino/administración & dosificación , Ofloxacino/química , Poloxámero/química , Resistencia a la Tracción
4.
Int J Pharm ; 456(2): 560-8, 2013 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-23965434

RESUMEN

The purpose of the present study was to investigate lecithin-rice bran oil rheological properties with the view to consider these as potential saliva substitutes in patients with severe xerostomia and salivary hypofunction. Pseudo-ternary phase diagrams of rice bran oil, lecithin and water mixtures were constructed and characterised using polarising light microscopy. Viscoelastic properties, which we hypothesise are important determinants in product performance, were analysed using both flow and oscillatory rheology. Rheological properties were influenced by composition, frequency and shear stress. Frequency-dependent viscoelasticity was observed in some formulations where viscosity dominated (tanδ>1) at frequencies under 5 Hz and elasticity dominated (tanδ<1) at higher frequencies. Threshold frequencies were determined for each formulation, where a peak in loss tangent was observed, coinciding with a reduction in the storage modulus and increase in loss modulus. The frequency-dependent behaviour of emulsions are of interest because these combinations exhibit viscous behaviour at low frequencies, which may improve lubrication of the oral cavity at rest, whereas increased elasticity at higher frequencies may improve retention during higher-shear tasks such as swallowing and speaking.


Asunto(s)
Lecitinas/química , Saliva Artificial/química , Saliva/química , Sustancias Viscoelásticas/química , Xerostomía , Emulsiones , Humanos , Lecitinas/administración & dosificación , Saliva Artificial/administración & dosificación , Sustancias Viscoelásticas/administración & dosificación , Xerostomía/tratamiento farmacológico
7.
J Pharm Sci ; 96(8): 2074-89, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17301966

RESUMEN

Formulations containing poloxamer 407 (P407), carbopol 934P (C934P), and propolis extract (PE) were designed for the treatment of periodontal disease. Gelation temperature, in vitro drug release, rheology, hardness, compressibility, adhesiveness, mucoadhesion, and syringeability of formulations were determined. Propolis release from formulations was controlled by the phenomenon of relaxation of polymer chains. Formulations exhibited pseudoplastic flow and low degrees of thixotropy or rheopexy. In most samples, increasing the concentration of C934P content significantly increased storage modulus (G'), loss modulus (G''), and dynamic viscosity (eta'), at 5 degrees C, G'' exceeded G'. At 25 and 37 degrees C, eta' of each formulation depended on the oscillatory frequency. Formulations showed thermoresponsive behavior, existing as a liquid at room temperature and gel at 34-37 degrees C. Increasing the C934P content or temperature significantly increased formulation hardness, compressibility, and adhesiveness. The greatest mucoadhesion was noted in the formulation containing 15% P407 (w/w) and 0.25% C934P (w/w). The work of syringeability values of all formulations were similar and very desirable with regard to ease of administration. The data obtained in these formulations indicate a potentially useful role in the treatment of periodontitis and suggest they are worthy of clinical evaluation.


Asunto(s)
Adhesivos/química , Antiinfecciosos/química , Enfermedades Periodontales/tratamiento farmacológico , Própolis/química , Adhesivos/uso terapéutico , Antiinfecciosos/uso terapéutico , Sistemas de Liberación de Medicamentos , Geles , Técnicas In Vitro , Cinética , Própolis/uso terapéutico , Reología , Temperatura , Viscosidad
8.
J Pharm Sci ; 92(5): 995-1007, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12712419

RESUMEN

This study examined the rheological and mucoadhesive properties of polymeric systems composed of the bioadhesive copolymer poly(methylvinylether-co-maleic anhydride), PMVE/MA and poly(vinylpyrrolidone, PVP) as candidate platforms for improved drug delivery to the oral cavity. Aqueous, neutral formulations were prepared containing PMVE/MA (10 or 15% w/w) and PVP (0-9% w/w). The rheological properties were examined at 20 +/- 0.1 degrees C using both oscillatory rheometry (0.01 to 1.0 Hz at a constant strain of 1.0 x 10(-3) rad) and controlled stress flow rheometry using a Carri-Med CSL(2)-100 rheometer. The mechanical properties were examined using texture profile analysis (15-mm depth of insertion, 9 mm s(-1) rate of insertion, 15 s delay period between the end of the first and beginning of the second compressions). The interaction of the various formulations with mucin was examined using oscillatory rheometry. All formulations exhibited pseudoplastic flow with minimal thixotropy. Increasing the concentration of each polymeric component increased the zero-rate viscosity (calculated using the Cross model), hardness, compressibility, the storage (G') and loss (G") moduli, and decreased the loss tangent. These observations may be due to greater polymeric entanglement between adjacent polymer chains. Specifically, rheological synergy was observed between PMVE/MA and PVP, evidence of complexation between these two polymers. From the relationship between the viscoelastic properties and oscillatory frequency, and the mathematical comparison of steady and oscillatory shear response of formulations using the Cox-Merz equation, it may be concluded that formulations containing 15% w/w PMVE/MA and either 6 or 9% w/w PVP exhibited rheological properties that were consistent with gel behavior. All other formulations exhibited rheological properties that resembled polymeric liquids. Increasing the concentrations of PMVE/MA and PVP significantly increased the interaction with mucin, the rheological synergy between the polymeric formulations and mucin and, in addition, the adhesiveness of the formulations. This is evidence of the muco/bioadhesive properties of the formulations. Conversely, the time of contact between each formulation and mucin did not affect their resultant interaction. In conclusion, this study has uniquely described the rheological and mucoadhesive properties of aqueous systems composed of PMVE/MA and PVP. In particular, the concentrations required for gel formation have been defined and the interaction between these two polymeric components illustrated using rheological methods. Furthermore, the simultaneous analysis of rheological, mechanical, and mucoadhesive data provided an insight into their potential utility as platforms for drug delivery systems for application to the oral cavity.


Asunto(s)
Maleatos/química , Mucinas/química , Polietilenos/química , Povidona/química , Adhesivos , Administración Tópica , Fenómenos Químicos , Química Farmacéutica , Química Física , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Incompatibilidad de Medicamentos , Geles , Excipientes Farmacéuticos/química , Reología
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