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1.
Glob Pediatr Health ; 9: 2333794X221124906, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36247807

RESUMEN

The Community Social Paediatrics approach (CSPA) is a comprehensive and personalized approach to care that is becoming more widely used throughout Canada. However, data on its implementation fidelity remain scarce. The purpose of this research was to assess the implementation fidelity of a CSPA established in 2017 in Canada. Data were collected through focus group interviews with the CSPA team using an implementation fidelity grid based on the Dr. Julien Foundation standard accreditation criteria. Results showed that on one hand, administrative and financial management and governance were among those domains with lower ratings. On the other hand, assessment/orientation and follow-up/support had high levels of fidelity of implementation. This research helps to better understand which factors are contributing to varying levels of fidelity of implementation. To reach an increased level of fidelity of implementation, it is recommended that adequate resources be in place.

2.
Comput Struct Biotechnol J ; 17: 1184-1194, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31528298

RESUMEN

PURPOSE: Aluminum-based adjuvants including aluminum phosphate (AlPO4) are commonly used in many human vaccines to enhance immune response. The interaction between the antigen and adjuvant, including the physical adsorption of antigen, may play a role in vaccine immunogenicity and is a useful marker of vaccine product quality and consistency. Thus, it is important to study the physicochemical properties of AlPO4, such as particle size and chemical composition. Control of the vaccine adjuvant throughout the manufacturing process, including raw materials and the intermediate and final product stages, can be effectively achieved through monitoring of such key product attributes to help ensure product quality. METHODS: This study focuses on the compositional analysis of AlPO4 adjuvant at the intermediate and final manufacturing stages using the off-line methods Fourier-Transform Infrared (FTIR) and Raman spectroscopy, X-ray Photoelectron Spectroscopy (XPS), and the in-line method Attenuated Total Reflectance (ATR). Particle size distribution of AlPO4 was measured off-line using Laser diffraction (LD) and in-line using Focused Beam Reflectance Measurement (FBRM®). RESULTS: There was no observable difference in size distribution between the intermediate and final stage AlPO4 by off-line and in-line analysis, in both small- or large-scale production samples. Consistent peak shifts were observed in off-line and in-line infrared (IR) spectroscopy as well as off-line XPS for both small- and large-scale AlPO4 manufacturing runs. Additionally, IR spectroscopy and FBRM® for size distribution were used as in-line process analytical technology (PAT) to monitor reaction progress in real-time during small-scale AlPO4 manufacturing from raw materials. The small-scale adsorption process of a model protein antigen (Tetanus toxoid) to AlPO4 adjuvant was also monitored by in-line ReactIR probe. CONCLUSION: This study demonstrated that in-line PAT can be used to monitor particle size and chemical composition for the various stages of adjuvant manufacturing from raw materials through intermediate to final adjuvant product stage. Similar approaches can be utilized to help assess lot-to-lot consistency during adjuvant manufacturing and vaccine product development. Moreover, the use of in-line PAT is highly conductive to advanced manufacturing strategies such as real-time product release testing and automated processes of the future.

3.
J Dent Educ ; 83(4): 464-473, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30936212

RESUMEN

The Association of Canadian Faculties of Dentistry (ACFD) recently developed a proposal that reflects its evolving understanding of competency-based dental education. The ACFD proposal was developed into an Educational Framework for the Development of Competency in Dental Programs and has been adopted by all ten Canadian dental schools as the basis for their ongoing curriculum development and assessment. This framework identifies five global competencies that provide a big picture of the complex skills, knowledge, and behaviors that dental graduates must demonstrate. Detail for clarification and illustration is provided by more comprehensive "components" of each area that elaborate on the global statement and by a new dimension that assists with assessment: "indicators" of the specific knowledge, skills, and behaviors that can be measured as steps towards developing competence. In the information supporting understanding and assessment of the five key areas are both the existing national competency statements to facilitate the use of the framework by other stakeholders and a parallel set of knowledge, skills, and abilities statements developed by the National Dental Examining Board of Canada (NDEB) as the starting point for updating its examination blueprints. This article outlines the development, structure, and contents of the ACFD Educational Framework in the hope that it can serve as the foundation for a new Canadian national competencies document serving all national stakeholders.


Asunto(s)
Competencia Clínica/normas , Educación en Odontología/normas , Docentes de Odontología , Sociedades Odontológicas/normas , Comités Consultivos , Canadá , Educación Basada en Competencias/normas , Humanos
4.
Comput Struct Biotechnol J ; 17: 14-20, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30581540

RESUMEN

PURPOSE: The goal of this study is to set an empirical baseline to map the structure-function relation of the antigens from the commercialized vaccine products. METHODS: To study the structural changes of protein antigens after adsorption several analytical tools including DLS, FTIR, Fluorescence, LD, and SEM have been used. RESULTS: All antigens have shown wide range of hydrodynamic diameter from 7 nm to 182 nm. Upon adjuvantation, the size distribution has become narrow, ranging from 10 to 12 µm, and has been driven by the derived diameter of aluminum phosphate (AlPO4) adjuvant. Further to examine size and morphology of adsorbed antigens, SEM has been used. The SEM results have demonstrated that the AlPO4 adjuvant suspension and adsorbed proteins consist of submicron particles that form a continuous porous surface. Diphtheria Toxoid (DT), Tetanus Toxoid (TT), and chemically-modified Filamentous Haemagglutinin (FHA) have shown surface adsorption to AlPO4. Secondary structure alpha-helix and beta-sheet content of DT and TT has increased after adsorption to AlPO4 adjuvant as shown by FTIR, whereas no significant changes were noted for other protein antigens. The results from Intrinsic Fluorescence have shown a structural rearrangement in DT and TT, consistent with the FTIR results. Multivalent vaccine product identity has been determined by FTIR as unique fingerprint spectrum. CONCLUSION: The globular proteins such as DT and TT have shown changes in secondary structure upon adsorption to AlPO4, whereas fibrillar protein FHA has not been affected by adsorption. FTIR can be used as a lean technique to confirm product identity at different manufacturing sites.

5.
Anal Chem ; 86(23): 11722-6, 2014 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-25369204

RESUMEN

In desorption electrospray ionization mass spectrometry (DESI-MS), the type of surface in addition to low gas and solvent flow rates help to avoid the "splashing of solvent" or "washing effect", by which samples are promptly removed from the surface by the spray. These effects operate on smooth surfaces and generally result in unstable signals as the spray moves over the spot. The aim of this work is to compare the performance of functionalized porous silicon surfaces (pSi) for small molecules analysis with regard to the stability of the signal and the limits of detection (LODs) observed in DESI-MS. The results showed that functional groups, like 1-decene and heptadecafluoro-1,1,2,2-tetrahydrodecyl trimethoxysilane, on pSi surface provides a good alternative for dried spot analysis by DESI-MS, improving stability of the signal and the LODs. This improvement is possible because the dual process containing the weak sample-surface interactions of the hydrophobic characteristic of the functional groups and increasing the surface area of interaction between the sample and the thin solvent film created by the DESI spray, resulting in more effective dissolution of the analyte in the spray solvent without fast removal of the sample.

6.
PLoS Pathog ; 9(5): e1003363, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23717202

RESUMEN

The genomes of plus-strand RNA viruses contain many regulatory sequences and structures that direct different viral processes. The traditional view of these RNA elements are as local structures present in non-coding regions. However, this view is changing due to the discovery of regulatory elements in coding regions and functional long-range intra-genomic base pairing interactions. The ∼4.8 kb long RNA genome of the tombusvirus tomato bushy stunt virus (TBSV) contains these types of structural features, including six different functional long-distance interactions. We hypothesized that to achieve these multiple interactions this viral genome must utilize a large-scale organizational strategy and, accordingly, we sought to assess the global conformation of the entire TBSV genome. Atomic force micrographs of the genome indicated a mostly condensed structure composed of interconnected protrusions extending from a central hub. This configuration was consistent with the genomic secondary structure model generated using high-throughput selective 2'-hydroxyl acylation analysed by primer extension (i.e. SHAPE), which predicted different sized RNA domains originating from a central region. Known RNA elements were identified in both domain and inter-domain regions, and novel structural features were predicted and functionally confirmed. Interestingly, only two of the six long-range interactions known to form were present in the structural model. However, for those interactions that did not form, complementary partner sequences were positioned relatively close to each other in the structure, suggesting that the secondary structure level of viral genome structure could provide a basic scaffold for the formation of different long-range interactions. The higher-order structural model for the TBSV RNA genome provides a snapshot of the complex framework that allows multiple functional components to operate in concert within a confined context.


Asunto(s)
Genoma Viral/fisiología , Conformación de Ácido Nucleico , ARN Viral/química , ARN Viral/genética , Tombusvirus/genética , Acilación , Cucumis sativus/virología , Modelos Genéticos , Modelos Moleculares , Células Vegetales/virología , ARN Viral/ultraestructura
7.
ACS Appl Mater Interfaces ; 4(11): 6211-5, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23113755

RESUMEN

A new class of triarylamine compound functionalized with bulky triisopropylsilyl ether (-OTIPS) groups is used as a hole transport material in dye-sensitized solar cells (DSSCs). Using both optical and photoelectrochemical techniques, we compared the performance of this compound with that of a parent compound containing methyl ethers as well as the conventional I3⁻/I⁻ redox couple. DSSCs fabricated with the triisopropylsilyl ether-substituted triarylamine exhibited high open circuit potentials (V(oc) > 0.9 V on average) and efficiencies of up to 1.9%. However, cells fabricated with triarylamine containing methyl ethers performed very poorly, pointing to the importance of -OTIPS in the overall performance of this material.


Asunto(s)
Aminas/química , Colorantes/química , Suministros de Energía Eléctrica , Silicio/química , Energía Solar , Diseño de Equipo , Análisis de Falla de Equipo , Oxidación-Reducción
8.
Biochemistry ; 51(16): 3523-30, 2012 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-22482799

RESUMEN

Transthyretin (TTR) is a cerebrospinal fluid and serum protein that undergoes ordered aggregation (amyloidogenesis) in familial amyloidotic polyneuropathy (FAP) and senile systemic amyloidosis (SSA). It is now widely accepted that dissociation of the native TTR tetramer is a precondition for amyloidogenesis; thus, molecules that stabilize the tetramer have received much attention as potential TTR amyloidosis inhibitors. Many of these inhibitors bind to the thyroxine (T(4)) binding pocket and interact specifically with a section of the TTR sequence, corresponding to residues 105-115, that is implicated in amyloidogenic propensity. In this work, we study the effects of "stabilizing" inhibitors on ordered aggregation of TTR(105-115) peptide. We show that molecules known to bind full-length TTR at the T(4) site are potent, specific inhibitors of ordered aggregation, while molecules that do not interact with TTR exhibit milder, nonspecific disruption through a "hyperbundling" effect. Our results suggest that, in addition to annealing the native tetramer, "stabilizing" inhibitors may also directly disrupt amyloidogenic aggregation of TTR monomers through specific interactions with the exposed TTR(105-115) sequence.


Asunto(s)
Amiloide/química , Amiloidosis/metabolismo , Prealbúmina/química , Amiloide/metabolismo , Neuropatías Amiloides Familiares/metabolismo , Humanos , Cinética , Péptidos/química , Péptidos/metabolismo , Prealbúmina/antagonistas & inhibidores , Prealbúmina/metabolismo , Pliegue de Proteína
9.
Biochemistry ; 49(28): 5829-31, 2010 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-20560641

RESUMEN

Amyloidogenic aggregation has been the subject of intense research over the past few decades, but the mechanisms underlying the early stages of amyloidogenesis remain elusive. Here we demonstrate for the first time manipulation of amyloidogenesis based on an atomic level map of peptide-fibril interactions in early- and late-stage ordered aggregation. Several point mutants with specific amyloidogenic properties are introduced, including one that "stalls" early in the aggregation process, forming early-stage fibrillar aggregates, but not mature fibrils.


Asunto(s)
Péptidos/química , Interacciones Farmacológicas , Péptidos/genética , Mutación Puntual
10.
Biophys Chem ; 144(1-2): 1-8, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19501449

RESUMEN

One of the central aims of amyloid research is to identify chemical and structural features that confer amyloidogenic propensity. In this study, we use Saturation Transfer Difference (STD) NMR spectroscopy to acquire an atom-specific map of the interactions between soluble and aggregated Transthyretin peptide (TTR(105-115)) in early- and late-stage amyloidogenesis. Atomic Force Microscopy (AFM) was used to monitor the transition of early-stage samples, containing protofilaments, to late-stage samples composed of fully-mature fibrils. Progressive aggregation was accompanied by an increase in the correlation time tau(c) of soluble TTR(105-115) as indicated by (1)H NMR line broadening, but no significant change in the (1)H chemical shifts. The STD profile of backbone amide protons is in good agreement with an earlier computational study predicting hydrogen bonding propensity for each residue in small TTR(105-115) aggregates (Paci et al., J. Mol. Biol. (2004) 555-569). The STD profiles of C(alpha) and C(beta) protons identify a central aliphatic region of the peptide, Ala108-Leu111, that plays a crucial, but different role in early- and late-stage amyloidogenesis. In general, the STD profiles of early and fully-mature samples are dissimilar, suggesting different mechanisms of self-assembly in protofilaments and mature amyloid fibrils. The early-stage mechanism appears to be more dependent on main-chain hydrogen bonding, while the late-stage mechanism involves an increased number of interactions between bulky side chains.


Asunto(s)
Amiloide/química , Prealbúmina/química , Enlace de Hidrógeno , Espectroscopía de Resonancia Magnética , Microscopía de Fuerza Atómica , Péptidos/química , Unión Proteica
11.
Chemistry ; 14(4): 1351-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18080264

RESUMEN

A method has been devised for the microwave-assisted, continuous-flow preparation of indole alkaloids by a two-step aryl amination/cross-coupling sequence of bromoalkenes and 2-bromoanilines. This process requires both the presence of a metal-lined flow tube (a 1180 micron capillary) and the Pd PEPPSI-IPr catalyst; without either, the catalyst or the film, there is zero turnover of this catalytic process. A silver film has been shown to provide some conversion (48-62 %), but optimal results (quantitative) across a variety of bromoalkenes and bromoanilines were achieved by using a highly porous palladium film. Possible roles for the Pd film are considered, as is the interplay of the catalyst and the film.

12.
J Chromatogr A ; 1135(2): 194-202, 2006 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-17054966

RESUMEN

Flat H-terminated Si(111) substrates modified with alkyl monolayers terminated with hydrophobic and hydrophilic functional groups were prepared using known surface functionalization methods and characterized by FTIR, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The surfaces were then used for the study of non-specific binding of proteins from complex mixtures (using standard mixture of proteins with average molecular weight approximately 6-66 kDa) by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Protein adsorption on these surfaces (following on-probe fractionation of the mixture) was found to be dependent on the nature of surface functional groups, and nature and pH of rinsing solutions used. The results obtained in this work demonstrate that simple silicon-based surface modifications can be effective for direct analysis of complex mixtures by MALDI-MS. Preliminary results obtained using similarly functionalized porous silicon substrates proved that such substrates are (due to their increased surface areas) better performing than flat silicon.


Asunto(s)
Sondas Moleculares , Proteínas/química , Silicio/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Adsorción , Concentración de Iones de Hidrógeno , Microscopía de Fuerza Atómica , Peso Molecular , Espectroscopía Infrarroja por Transformada de Fourier
13.
Langmuir ; 22(12): 5301-7, 2006 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-16732656

RESUMEN

Chemical force titrations-plots of the adhesive force between an atomic force microscope tip and sample as a function of pH-were acquired on alkyl monolayer-derivatized Si(111) surfaces. Gold-coated AFM tips modified with thioalkanoic acid self-assembled monolayers (SAM) were employed. Alkyl monolayer-derivatized Si(111) surfaces terminated with methyl, carboxyl, and amine groups were produced via hydrosilylation reactions between 1-alkene reagents and H-terminated silicon. The functionalized surfaces were characterized using standard surface science techniques (AFM, FTIR, and XPS). Titration of the methyl-terminated surface using the modified (carboxyl-terminated) atomic force microscope tip resulted in a small pH-independent hydrophobic interaction. Titration of the amine-terminated surface using the same tip resulted in the determination of a surface pKa of 5.8 for the amine from the pH value from the maximum in the force titration curve. A pK(1/2) of 4.3 was determined for the carboxyl-terminated Si(111) in a similar way. These results will be discussed in relation to the modified Si(111) surface chemistry and organic layer structure, as well as with respect to existing results on Au surfaces modified with SAMs bearing the same functional groups.

15.
Chem Commun (Camb) ; (45): 5659-61, 2005 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-16292381

RESUMEN

Alkyl monolayer modified porous silicon functional surfaces are employed for selective binding of proteins from complex mixtures (through washing of the deposited mixture spot using appropriate buffer) and MALDI-MS is used to detect the components retained on the surface.


Asunto(s)
Proteínas/química , Proteínas/metabolismo , Silicio/química , Porosidad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Especificidad por Sustrato
16.
FEBS Lett ; 572(1-3): 33-40, 2004 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-15304320

RESUMEN

Peroxisome proliferator-activated receptor gamma (PPARgamma) ligands have been shown to inhibit the effects of proinflammatory cytokines such as interleukin-1beta (IL-1beta). This cytokine plays a key role in articular pathophysiologies by inducing the production of inflammatory mediators such as nitric oxide (NO) and prostaglandin E(2) (PGE(2)). We previously demonstrated that 15d-PGJ(2) was more potent than troglitazone to counteract IL-1beta effects on chondrocytes. Here, we studied the action of 15d-PGJ(2) on intracellular targets in nuclear factor-kappaB (NF-kappaB) signalling pathway in IL-1beta treated rat chondrocytes. We found that 15d-PGJ(2) decreased inhibitor kappaBalpha (IkappaBalpha) degradation but not its phosphorylation by specifically inhibiting IkappaB kinase beta (IKKbeta), but not IKKalpha, enzymatic activity. We further evaluated the involvement of PPARgamma in the anti-inflammatory action of its ligands. In chondrocytes overexpressing functional PPARgamma protein, 15d-PGJ(2) pre-treatment inhibited inducible NO synthase and COX-2 mRNA expression, nitrite and PGE(2) production, p65 translocation and NF-kappaB activation. Troglitazone or rosiglitazone pre-treatment had no effect. 15d-PGJ(2) exhibited the same effect in chondrocytes overexpressing mutated PPARgamma protein. These results suggest that 15d-PGJ(2) exerts its anti-inflammatory effect in rat chondrocytes by a PPARgamma-independent mechanism, which can be conferred to a partial inhibition of IkappaBalpha degradation.


Asunto(s)
Condrocitos/metabolismo , Proteínas I-kappa B/metabolismo , Interleucina-2/farmacología , Prostaglandina D2/farmacología , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores Citoplasmáticos y Nucleares/fisiología , Factores de Transcripción/fisiología , Animales , Antiinflamatorios/farmacología , Células Cultivadas , Condrocitos/efectos de los fármacos , Condrocitos/enzimología , Dinoprostona/metabolismo , Femenino , Quinasa I-kappa B , Inhibidor NF-kappaB alfa , FN-kappa B/antagonistas & inhibidores , Óxido Nítrico/metabolismo , Prostaglandina D2/análogos & derivados , Ratas , Ratas Wistar , Receptores Citoplasmáticos y Nucleares/efectos de los fármacos , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción/efectos de los fármacos , Activación Transcripcional
17.
Hum Gene Ther ; 13(12): 1441-50, 2002 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-12215265

RESUMEN

Administration of monoclonal antibodies directed against the leukocyte function-associated antigen 1 (LFA-1)-intercellular adhesion molecule 1 (ICAM-1) pathway showed that these costimulatory molecules play a key role in allograft rejection. Here, adenoviral gene transfer of an immunoadhesin, sICAM-1/Ig, was used to prolong islet allograft survival in a mouse model, and was compared with anti-LFA-1 antibody administration. A replication-deficient recombinant adenoviral vector encoding a chimeric protein, in which the extracellular domain of ICAM-1 is covalently linked to the C(H)2-C(H)3 domains of an IgG1, was used for gene transfer. C3H murine islets were transplanted under the kidney capsule of streptozotocin-induced diabetic BALB/c mice. Experimental groups underwent adenovirus vector administration either in vivo (intravenous injection) or ex vivo (gene transfer to the graft), and control groups received either an empty vector (Ad.null) or an anti-LFA-1 monoclonal antibody. Graft survival was significantly prolonged by in vivo sICAM-1/Ig gene transfer as compared with both Ad.null and anti-LFA-1 groups, but not by ex vivo gene transfer. Histological examination of the grafts showed the presence of a mononuclear infiltrate within functioning grafts, suggesting that the homing of alloreactive T cells was not altered. In vitro T cell proliferation experiments indicated that sICAM-1/Ig exerted agonist effects on both CD4(+) and CD8(+) T cells.


Asunto(s)
Adenoviridae , Técnicas de Transferencia de Gen , Vectores Genéticos , Supervivencia de Injerto/genética , Inmunoglobulina G/genética , Molécula 1 de Adhesión Intercelular/genética , Trasplante de Islotes Pancreáticos/inmunología , Animales , Anticuerpos Monoclonales/administración & dosificación , Molécula 1 de Adhesión Intercelular/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Proteínas Recombinantes de Fusión , Linfocitos T/inmunología
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