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1.
Can J Kidney Health Dis ; 10: 20543581231217833, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38107157

RESUMO

Background: Following onset of the COVID-19 pandemic, chronic kidney disease (CKD) clinics in BC shifted from established methods of mostly in-person care delivery to virtual care (VC) and thereafter a hybrid of the two. Objectives: To determine strengths, weaknesses, quality-of-care delivery, and key considerations associated with VC usage to inform optimal way(s) of integrating virtual and traditional methods of care delivery in multidisciplinary kidney clinics. Design: Qualitative evaluation. Setting: British Columbia, Canada. Participants: Patients and health care providers associated with multidisciplinary kidney care clinics. Methods: Development and delivery of semi-structured interviews of patients and health care providers. Results: 11 patients and/or caregivers and 12 health care providers participated in the interviews. Participants reported mixed experiences with VC usage. All participants foresaw a future where both VC and in-person care was offered. A reported benefit of VC was convenience for patients. Challenges identified with VC included difficulty establishing new therapeutic relationships, and variable of abilities of both patients and health care providers to engage and communicate in a virtual format. Participants noted a preference for in-person care for more complex situations. Four themes were identified as considerations when selecting between in-person and VC: person's nonmedical context, support available, clinical parameters and tasks to be completed, and clinic operations. Participants indicated that visit modality selection is an individualized and ongoing process involving the patient and their preferences which may change over time. Health care provider participants noted that new workflow challenges were created when using both VC and in-person care in the same clinic session. Limitations: Limited sample size in the setting of one-on-one interviews and use of convenience sampling which may result in missing perspectives, including those already facing challenges accessing care who could potentially be most disadvantaged by implementation of VC. Conclusions: A list of key considerations, aligned with quality care delivery was identified for health care providers and programs to consider as they continue to utilize VC and refine how best to use different visit modalities in different patient and clinical situations. Further work will be needed to validate these findings and evaluate clinical outcomes with the combination of virtual and traditional modes of care delivery. Trial registration: Not registered.


Contexte: Après le début de la pandémie de COVID-19, les cliniques d'insuffisance rénale chronique (IRC) de la Colombie-Britannique sont passées d'une prestation de soins traditionnelle fondée principalement sur les visites en personne à des soins en mode virtuel, puis à un modèle hybride combinant les deux méthodes. Objectifs: Déterminer les avantages et les faiblesses des soins en mode virtuel, ainsi que la qualité de la prestation des soins et les principaux facteurs à considérer relativement à l'utilization des soins en mode virtuel, afin d'informer sur les meilleurs moyens d'intégrer les méthodes virtuelles et traditionnelles de prestation des soins dans les cliniques multidisciplinaires de néphrologie. Conception: Évaluation qualitative. Cadre: Colombie-Britannique (Canada). Sujets: Patients et prestataires de soins associés à des cliniques multidisciplinaires de soins rénaux. Méthodologie: Élaboration et réalisation d'entrevues semi-structurées auprès de patients et de prestataires de soins de santé. Résultats: En tout, 11 patients et/ou soignants et 12 prestataires de soins de santé ont participé aux entrevues. Les participants ont fait état d'expériences mitigées avec les soins en mode virtuel. Tous les participants envisageaient un futur où les soins seront offerts tant en mode virtuel qu'en personne. Un des avantages mentionnés des soins en mode virtuel est la commodité pour les patients. Parmi les défis mentionnés figuraient la difficulté à établir de nouvelles relations thérapeutiques et les capacités variables des patients et des prestataires de soins de santé à établir une relation et à communiquer en mode virtuel. Les participants ont noté une préférence pour les soins en personne dans les situations plus complexes. Quatre thèmes ont été identifiés comme facteurs à prendre en compte dans le choix entre les soins virtuels ou en personne: le contexte non médical de la personne, l'aide disponible, les paramètres cliniques et les tâches à accomplir, et les opérations de la clinique. Les participants ont indiqué que le choix de la modalité pour les visites est un processus individualisé et continu impliquant le patient et ses préférences, lesquelles peuvent changer au fil du temps. Les prestataires de soins ont indiqué que le fait d'offrir à la fois des soins virtuels et en personne dans une même séance clinique créait de nouveaux défis en matière de flux de travail. Limites: La taille limitée de l'échantillon pour les entrevues individuelles et l'utilization d'un échantillonnage de commodité pourraient avoir manqué certains points de vue, notamment celui de personnes déjà confrontées à des difficultés d'accès aux soins et qui pourraient être les plus désavantagées par la mise en œuvre de soins en mode virtuel. Conclusion: Une liste de facteurs-clé à prendre en compte pour une prestation de soins de qualité a été établie à l'attention des prestataires de soins de santé et des programs qui continuent à utiliser les soins en mode virtuel, et décrit la meilleure façon d'utiliser les différentes modalités de visites dans différentes situations cliniques et pour différents patients. D'autres travaux seront nécessaires pour valider ces résultats et évaluer les résultats cliniques lorsqu'il y a combinaison des modes virtuel et traditionnel pour la prestation des soins.

2.
Can J Kidney Health Dis ; 9: 20543581221103103, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35676893

RESUMO

Background: Multidisciplinary care of patients with chronic kidney disease (CKD) as it previously existed was predicated on an evidence and experience base of improved patient outcomes within an established and well-described service delivery model. The onset of the COVID-19 pandemic brought with it a departure from this established care delivery model toward integration of virtual care and in-person care. Objective: To develop an evaluation framework to determine whether this shift in service delivery models has affected quality of multidisciplinary kidney care and/or patient-clinician interactions and relationships. Design: A sequential multiphase, mixed-methods evaluation. Setting: All 15 British Columbia (BC) multidisciplinary kidney care clinics (KCCs). Participants: All patients and all clinicians in all KCCs across BC will be invited to participate in the planned evaluation. Measurements: Qualitative and quantitative feedback from patients and families living with CKD and KCC clinicians. Methods: The planned multiphase evaluation of virtual care integration in KCCs will be conducted across all 15 KCCs in the province of BC, Canada. The following phases are proposed: (1) review of current virtual care integration and practices, (2) assessment of patient and clinician experiences and perspectives via semi-structured interviews, (3) validation of those patient and clinician perspectives via survey of a larger sample, (4) compilation and analysis of all phases to provide informed recommendations for patient and visit format selection in a mixed in-person and virtual multidisciplinary clinic setting. Limitations: This work will not capture any information about the relationship between differences in virtual usage parameters and clinical outcomes or financial implications. Conclusions: There is no existing framework for either evaluation of multidisciplinary CKD care quality in a virtual setting or evaluation of care quality following a substantial change in service delivery models. The proposed evaluation protocol will enable better understanding of the nuances in kidney care delivery in this new format and inform how best to optimize the integration of virtual and pre-existing formats into kidney clinic care delivery beyond the pandemic. Beyond the current evaluation, this protocol may be of use for other jurisdictions to evaluate their own local instances of virtual care implementation and integration. The model may be adapted to evaluate quality of multidisciplinary kidney care delivery following other changes to clinic service delivery models.


Contexte: Les soins multidisciplinaires prodigués aux patients atteints d'insuffisance rénale chronique (IRC), tels qu'ils existaient auparavant, étaient fondés sur une base de preuves et d'expérience de l'amélioration des résultats pour les patients dans le cadre d'un modèle de prestation de services établi et bien décrit. Le début de la pandémie COVID-19 a créé une fracture par rapport à ce modèle établi de prestation de soins, à la faveur d'une intégration des soins virtuels et des soins en personne. Objectif: Élaborer un cadre d'évaluation permettant de déterminer si ce changement dans les modèles de prestation de services a eu une incidence sur la qualité des soins multidisciplinaires en santé rénale et/ou sur les interactions et les relations entre le patient et le clinicien. Type d'étude: Une évaluation multiphase séquentielle à méthodes mixtes. Cadre: Les 15 cliniques multidisciplinaires de soins rénaux (CMSR) de la C.-B. Participants: Tous les patients et cliniciens de toutes les CMSR de la Colombie-Britannique seront invités à participer à l'évaluation. Mesures: Les rétroactions qualitative et quantitative des patients atteints d'IRC et de leurs familles, ainsi que celles des cliniciens des CMSR. Méthodologie: L'évaluation multiphase prévue de l'intégration des soins virtuels dans les soins prodigués dans les CMSR sera menée dans les 15 CMSR de la Colombie-Britannique (C.-B.), au Canada. Les phases suivantes sont proposées: (1) examen de l'intégration et des pratiques actuelles en matière de soins virtuels, (2) évaluation des expériences et des perspectives des patients et des cliniciens par le biais d'entrevues semi-structurées, (3) validation de ces mêmes perspectives par le biais d'un sondage sur un échantillon plus large, (4) compilation et analyze des données recueillies lors de toutes les phases afin de fournir des recommandations éclairées pour le choix des patients et du format de la visite dans un contexte de clinique multidisciplinaire intégrant les consultations en personne et virtuelles. Limites: Ces travaux ne permettront pas de recueillir des informations sur la relation entre les différences dans les paramètres d'utilization virtuelle et les résultats cliniques ou les implications financières. Conclusion: En ce moment, il n'existe pas de cadre pour évaluer la qualité des soins multidisciplinaires en IRC dans un cadre virtuel ni pour évaluer la qualité des soins après un changement important dans les modèles de prestation de services. Le protocole d'évaluation proposé permettra de mieux comprendre les nuances dans la prestation des soins rénaux dans ce nouveau format et d'indiquer la meilleure façon d'optimiser l'intégration des formats virtuels et préexistants dans la prestation des soins en clinique rénale au-delà de la pandémie. Au-delà de l'évaluation actuelle, ce protocole pourra être utilisé par d'autres provinces pour évaluer leurs propres instances locales de mise en œuvre et d'intégration des soins virtuels. Le modèle peut être adapté pour évaluer la qualité de la prestation de soins multidisciplinaires aux reins à la suite d'autres changements apportés aux modèles de prestation de services en clinique.

3.
FEBS J ; 273(13): 2929-41, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16762038

RESUMO

The gram-positive soil bacterium Cellulomonas fimi is shown to produce at least two intracellular beta-N-acetylglucosaminidases, a family 20 beta-N-acetylhexosaminidase (Hex20), and a novel family 3-beta-N-acetylglucosaminidase/beta-glucosidase (Nag3), through screening of a genomic expression library, cloning of genes and analysis of their sequences. Nag3 exhibits broad substrate specificity for substituents at the C2 position of the glycone: kcat/Km values at 25 degrees C were 0.066 s(-1) x mM(-1) and 0.076 s(-1) x mM(-1) for 4'-nitrophenyl beta-N-acetyl-D-glucosaminide and 4'-nitrophenyl beta-D-glucoside, respectively. The first glycosidase with this broad specificity to be described, Nag3, suggests an interesting evolutionary link between beta-N-acetylglucosaminidases and beta-glucosidases of family 3. Reaction by a double-displacement mechanism was confirmed for Nag3 through the identification of a glycosyl-enzyme species trapped with the slow substrate 2',4'-dinitrophenyl 2-deoxy-2-fluoro-beta-D-glucopyranoside. Hex20 requires the acetamido group at C2 of the substrate, being unable to cleave beta-glucosides, since its mechanism involves an oxazolinium ion intermediate. However, it is broad in its specificity for the D-glucosyl/D-galactosyl configuration of the glycone: Km and kcat values were 53 microM and 482.3 s(-1) for 4'-nitrophenyl beta-N-acetyl-D-glucosaminide and 66 microM and 129.1 s(-1) for 4'-nitrophenyl beta-N-acetyl-D-galactosaminide.


Assuntos
Acetilglucosaminidase/química , Cellulomonas/enzimologia , beta-Glucosidase/química , beta-N-Acetil-Hexosaminidases/química , Sequência de Aminoácidos , Clonagem Molecular , Evolução Molecular , Biblioteca Gênica , Concentração de Íons de Hidrogênio , Cinética , Dados de Sequência Molecular , Filogenia , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
6.
Angew Chem Int Ed Engl ; 40(2): 417-420, 2001 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29712412

RESUMO

Engineering enzymes: The glutamic acid nucleophile of a retaining ß-mannosidase has been replaced with a serine residue to form a ß-mannosynthase. When the new enzyme is provided with an α-mannosyl fluoride donor and an appropriate acceptor, ß-mannoside linkages are synthesized. Remarkably, α-mannosyl fluoride can be generated in situ by providing the mannosynthase with excess fluoride ion.

9.
Biochemistry ; 44(38): 12700-8, 2005 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-16171384

RESUMO

The endo-beta-1,4-mannanase from the soil bacterium Cellulomonas fimi is a modular plant cell wall degrading enzyme involved in the hydrolysis of the backbone of mannan, one of the most abundant polysaccharides of the hemicellulosic network in the plant cell wall. The crystal structure of a recombinant truncated endo-beta-1,4-mannanase from C. fimi (CfMan26A-50K) was determined by X-ray crystallography to 2.25 A resolution using the molecular replacement technique. The overall structure of the enzyme consists of a core (beta/alpha)8-barrel catalytic module characteristic of clan GH-A, connected via a linker to an immunoglobulin-like module of unknown function. A complex with the oligosaccharide mannotriose to 2.9 A resolution has also been obtained. Both the native structure and the complex show a cacodylate ion bound at the -1 subsite, while subsites -2, -3, and -4 are occupied by mannotriose in the complex. Enzyme kinetic analysis and the analysis of hydrolysis products from manno-oligosaccharides and mannopentitol suggest five important active-site cleft subsites. CfMan26A-50K has a high affinity -3 subsite with Phe325 as an aromatic platform, which explains the mannose releasing property of the enzyme. Structural differences with the homologous Cellvibrio japonicus beta-1,4-mannanase (CjMan26A) at the -2 and -3 subsites may explain the poor performance of CfMan26A mutants as "glycosynthases".


Assuntos
Cellulomonas/enzimologia , Manosidases/química , Modelos Moleculares , Sequência de Aminoácidos , Cristalografia por Raios X , Manosidases/metabolismo , Dados de Sequência Molecular , Oligossacarídeos/metabolismo , Polissacarídeos/metabolismo , Alinhamento de Sequência , Trissacarídeos/química
10.
Biochemistry ; 42(23): 7195-204, 2003 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-12795616

RESUMO

The chemical mechanism of a retaining beta-mannosidase from Cellulomonas fimi has been characterized through steady-state kinetic analyses with a range of substrates, coupled with chemical rescue studies on both the wild-type enzyme and mutants in which active site carboxyl groups have been replaced. Studies with a series of aryl beta-mannosides of vastly different reactivities (pK(a)(lg) = 4-10) allowed kinetic isolation of the glycosylation and deglycosylation steps. Substrate inhibition was observed for all but the least reactive of these substrates. Brønsted analysis of k(cat) revealed a downward breaking plot (beta(lg) = -0.54 +/- 0.05) that is consistent with a change in rate-determining step (glycosylation to deglycosylation), and this was confirmed by partitioning studies with ethylene glycol. The pH dependence of k(cat)/K(m) follows an apparent single ionization of a group of pK(a) = 7.65 that must be protonated for catalysis. The tentative assignment of E429 as the acid-base catalyst of Man2A on the basis of sequence alignments with other family 2 glycosidases was confirmed by the increased turnover rate observed for the mutant E429A in the presence of azide and fluoride, leading to the production of beta-mannosyl azide and beta-mannosyl fluoride, respectively. A pH-dependent chemical rescue of E429A activity is also observed with citrate. Substantial oxocarbenium ion character at the transition state was demonstrated by the alpha-deuterium kinetic isotope effect for Man2A E429A of alpha-D(V) = 1.12 +/- 0.01. Surprisingly, this isotope effect was substantially greater in the presence of azide (alpha-D(V) = 1.166 +/- 0.009). Likely involvement of acid/base catalysis was revealed by the pH dependence of k(cat) for Man2A E429A, which follows a bell-shaped profile described by pK(a) values of 6.1 and 8.4, substantially different from that of the wild-type enzyme. The glycosidic bond cleaving activity of Man2A E519A and E519S nucleophile mutants is restored with azide and fluoride and appears to correlate with the corresponding "glycosynthase" activities. The contribution of the substrate 2-hydroxyl to stabilization of the Man2A glycosylation transition state (DeltaDeltaG() = 5.1 kcal mol(-1)) was probed using a 2-deoxymannose substrate. This value, surprisingly, is comparable to that found from equivalent studies with beta-glucosidases despite the geometric differences at C-2 and the importance of hydrogen bonding at that position. Modes of stabilizing the mannosidase transition state are discussed.


Assuntos
Cellulomonas/enzimologia , Manosidases/química , Sequência de Aminoácidos , Substituição de Aminoácidos , Sítios de Ligação , Catálise , Radioisótopos de Flúor , Glicosilação , Concentração de Íons de Hidrogênio , Cinética , Manosidases/genética , Manosidases/metabolismo , Manosídeos/química , Manosídeos/metabolismo , Mutagênese , Ressonância Magnética Nuclear Biomolecular/métodos , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Termodinâmica , beta-Manosidase
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