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1.
Fam Med Community Health ; 12(Suppl 3)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609087

RESUMEN

Storylines of Family Medicine is a 12-part series of thematically linked essays with accompanying illustrations that explore the many dimensions of family medicine, as interpreted by individual family physicians and medical educators in the USA and elsewhere around the world. In 'V: ways of thinking-honing the therapeutic self', authors present the following sections: 'Reflective practice in action', 'The doctor as drug-Balint groups', 'Cultivating compassion', 'Towards a humanistic approach to doctoring', 'Intimacy in family medicine', 'The many faces of suffering', 'Transcending suffering' and 'The power of listening to stories.' May readers feel a deeper sense of their own therapeutic agency by reflecting on these essays.


Asunto(s)
Medicina Familiar y Comunitaria , Médicos de Familia , Humanos , Reflexión Cognitiva , Emociones , Humanismo
2.
Nat Chem Biol ; 20(4): 521-529, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37919547

RESUMEN

Lis1 is a key cofactor for the assembly of active cytoplasmic dynein complexes that transport cargo along microtubules. Lis1 binds to the AAA+ ring and stalk of dynein and slows dynein motility, but the underlying mechanism has remained unclear. Using single-molecule imaging and optical trapping assays, we investigated how Lis1 binding affects the motility and force generation of yeast dynein in vitro. We showed that Lis1 slows motility by binding to the AAA+ ring of dynein, not by serving as a roadblock or tethering dynein to microtubules. Lis1 binding also does not affect force generation, but it induces prolonged stalls and reduces the asymmetry in the force-induced detachment of dynein from microtubules. The mutagenesis of the Lis1-binding sites on the dynein stalk partially recovers this asymmetry but does not restore dynein velocity. These results suggest that Lis1-stalk interaction slows the detachment of dynein from microtubules by interfering with the stalk sliding mechanism.


Asunto(s)
Dineínas Citoplasmáticas , Proteínas Asociadas a Microtúbulos , Dineínas Citoplasmáticas/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Dineínas/química , Saccharomyces cerevisiae/metabolismo
3.
Mult Scler ; 29(13): 1646-1658, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37842763

RESUMEN

BACKGROUND: The Symbol Digit Modalities Test (SDMT) is a gold-standard measure of cognitive efficiency and processing speed for people with multiple sclerosis (PwMS) but relies on vision and oculomotor function. OBJECTIVES: To develop and validate a new processing speed test with minimal memory involvement and no eye function requirements. METHODS: We created an Auditory Test of Processing Speed (ATOPS). A total of 122 PwMS, of whom 33 were severely disabled (median Expanded Disability Status Scale 8.0) and 37 healthy volunteers (HVs), were enrolled. We assessed sensitivity to discriminate MS participants from HVs, convergent validity between ATOPS and SDMT, sensitivity to discriminate between cognitively impaired (CI) and cognitively preserved (CP) MS participants, and correlations with MS pathology (overall brain lesion burden). Acceptability was examined with completion rates and participant ratings of ATOPS. RESULTS: ATOPS discriminated PwMS from HVs (d = 0.739-0.856), correlated with SDMT (|r| = 0.528-0.587), discriminated between CI and CP PwMS (d = 0.623-0.776), and correlated with lesion burden (r = 0.332-0.436). All groups indicated high favorability of ATOPS and severely disabled MS patients could be assessed by ATOPS more frequently than by SDMT (100% vs. 72.4% completion). CONCLUSIONS: ATOPS is a novel, accessible, and acceptable cognitive processing speed test that may be useful in clinical and/or research settings.


Asunto(s)
Esclerosis Múltiple , Velocidad de Procesamiento , Humanos , Teléfono Inteligente , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/psicología , Pruebas Neuropsicológicas , Cognición
4.
bioRxiv ; 2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-37693451

RESUMEN

Viruses exploit host cytoskeletal elements and motor proteins for trafficking through the dense cytoplasm. Yet the molecular mechanism that describes how viruses connect to the motor machinery is unknown. Here, we demonstrate the first example of viral microtubule trafficking from purified components: HIV-1 hijacking microtubule transport machinery. We discover that HIV-1 directly binds to the retrograde microtubule-associated motor, dynein, and not via a cargo adaptor, as previously suggested. Moreover, we show that HIV-1 motility is supported by multiple, diverse dynein cargo adaptors as HIV-1 binds to dynein light and intermediate chains on dynein's tail. Further, we demonstrate that multiple dynein motors tethered to rigid cargoes, like HIV-1 capsids, display reduced motility, distinct from the behavior of multiple motors on membranous cargoes. Our results introduce a new model of viral trafficking wherein a pathogen opportunistically 'hijacks' the microtubule transport machinery for motility, enabling multiple transport pathways through the host cytoplasm.

6.
Mult Scler ; 29(10): 1327-1336, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37503838

RESUMEN

BACKGROUND: Employment deterioration is common in people with multiple sclerosis (PwMS). Clinicians often learn of job loss after its occurrence, leaving no opportunity for preventive measures. OBJECTIVES: Identify which neuropsychological measures discriminate between healthy volunteers (HVs) and employed/disabled PwMS at baseline and predict work deterioration over 2 years. METHODS: We examined 198 PwMS with computerized tests such as the Processing Speed Test (PST) and conventional tests such as the Symbol-Digit Modalities Test (SDMT), administered at baseline. Employment was assessed via Buffalo Vocational Monitoring Survey. Univariate and regression analyses identified significant predictors of PwMS categorized as work-stable versus work-deteriorated status. RESULTS: PwMS were impaired on all baseline assessments relative to HVs (p's < 0.001). Post hoc analyses showed that employed PwMS and HVs performed similarly and better than work-disabled PwMS. At the univariate level, both PST and SDMT discriminated between work-deteriorated and work-stable PwMS (p's < 0.01). The logistic regression model accounting for all measures retained PST and the computerized Walking Speed Test. PwMS with increased negative work events had lower PST (p < 0.001), SDMT (p < 0.001), and BVMT-R (p < 0.01) scores than stable PwMS. The related regression model retained PST and BVMT-R (p < 0.001). CONCLUSION: Cognition, as measured by the PST and BVMT-R, are predictive of job deterioration in PwMS and may be a useful screening tool to identify those at high risk of unemployment.


Asunto(s)
Trastornos del Conocimiento , Esclerosis Múltiple , Humanos , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/psicología , Velocidad de Procesamiento , Trastornos del Conocimiento/diagnóstico , Cognición , Pruebas Neuropsicológicas , Empleo
7.
J Biol Chem ; 299(6): 104735, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37086789

RESUMEN

Dynein is the primary minus-end-directed microtubule motor protein. To achieve activation, dynein binds to the dynactin complex and an adaptor to form the "activated dynein complex." The protein Lis1 aids activation by binding to dynein and promoting its association with dynactin and the adaptor. Ndel1 and its paralog Nde1 are dynein- and Lis1-binding proteins that help control dynein localization within the cell. Cell-based assays suggest that Ndel1-Nde1 also work with Lis1 to promote dynein activation, although the underlying mechanism is unclear. Using purified proteins and quantitative binding assays, here we found that the C-terminal region of Ndel1 contributes to dynein binding and negatively regulates binding to Lis1. Using single-molecule imaging and protein biochemistry, we observed that Ndel1 inhibits dynein activation in two distinct ways. First, Ndel1 disfavors the formation of the activated dynein complex. We found that phosphomimetic mutations in the C-terminal domain of Ndel1 increase its ability to inhibit dynein-dynactin-adaptor complex formation. Second, we observed that Ndel1 interacts with dynein and Lis1 simultaneously and sequesters Lis1 away from its dynein-binding site. In doing this, Ndel1 prevents Lis1-mediated dynein activation. Together, our work suggests that in vitro, Ndel1 is a negative regulator of dynein activation, which contrasts with cellular studies where Ndel1 promotes dynein activity. To reconcile our findings with previous work, we posit that Ndel1 functions to scaffold dynein and Lis1 together while keeping dynein in an inhibited state. We speculate that Ndel1 release can be triggered in cellular settings to allow for timed dynein activation.


Asunto(s)
Proteínas Portadoras , Complejo Dinactina , Dineínas , Proteínas Asociadas a Microtúbulos , 1-Alquil-2-acetilglicerofosfocolina Esterasa/genética , 1-Alquil-2-acetilglicerofosfocolina Esterasa/metabolismo , Citoesqueleto/metabolismo , Complejo Dinactina/genética , Complejo Dinactina/metabolismo , Dineínas/genética , Dineínas/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Humanos , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo
8.
BJGP Open ; 7(2)2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36868788

RESUMEN

BACKGROUND: Formation of GP clusters began in Scotland in April 2016 as part of a new Scottish GP contract. They aim to improve the care quality for local populations (intrinsic role) and the integration of health and social care (extrinsic role). AIM: To compare predicted challenges of cluster implementation in 2016 with reported challenges in 2021. DESIGN & SETTING: Qualitative study of senior national stakeholders in primary care in Scotland. METHOD: Qualitative analysis of semi-structured interviews with 12 senior primary care national stakeholders in 2016 (n = 6) and 2021 (n = 6). RESULTS: Predicted challenges in 2016 included balancing intrinsic and extrinsic roles, providing sufficient support, maintaining motivation and direction, and avoiding variation between clusters. Progress of clusters in 2021 was perceived as suboptimal and was reported to vary significantly across the country, reflecting differences in local infrastructure. Practical facilitation (data, administrative support, training, project improvement support, and funded time) and strategic guidance from the Scottish Government was felt to be lacking. GP engagement with clusters was felt to be hindered by the significant time and workforce pressures facing primary care. These barriers were considered as collectively contributing to cluster lead 'burnout' and loss of momentum, exacerbated by inadequate opportunities for shared learning between clusters across Scotland. Such barriers preceded, but were perpetuated by, the impact of the COVID-19 pandemic. CONCLUSION: Apart from the COVID-19 pandemic, many of the challenges reported by stakeholders in 2021 were predicted in 2016. Accelerating progress in cluster working will require renewed investment and support applied consistently across the country.

9.
BJGP Open ; 7(2)2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36868787

RESUMEN

BACKGROUND: Pilot 'new models' of primary care have been funded across the UK since 2015, through various national transformation funds. Reflections and syntheses of evaluation findings provide an additional layer of insight into 'what works' in transforming primary care. AIM: To identify good practice in policy design, implementation, and evaluation for primary care transformation. DESIGN & SETTING: A thematic analysis of existing pilot evaluations in England, Wales, and Scotland. METHOD: Ten studies presenting evaluations of three national pilot studies - the Vanguard programme in England, the Pacesetter programme in Wales, and the National Evaluation of New Models of Primary Care in Scotland - were thematically analysed, and findings synthesised in order to identify lessons learnt and good practice. RESULTS: Common themes emerged across studies in all three countries at project and policy level, which can support or inhibit new models of care. At project level, these included the following: working with all stakeholders, including communities and front-line staff; providing the time, space, and support necessary for the project to succeed; agreeing on clear objectives from the outset; and support for data collection, evaluation, and shared learning. At policy level, more fundamental challenges related to the parameters for pilot projects, in particular, the typically short-term nature of funding, with an expectation of results within 2-3 years. Changing expectations about outcome measures or project guidance part-way through project implementation was also identified as a key challenge. CONCLUSION: Primary care transformation requires coproduction and a rich, contextual understanding of local needs and complexities. However, a mismatch between policy objectives (care redesign to better meet patient needs) and policy parameters (short timeframes) is often a significant challenge to success.

10.
Nat Commun ; 14(1): 1715, 2023 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-36973253

RESUMEN

Spindle formation in male meiosis relies on the canonical centrosome system, which is distinct from acentrosomal oocyte meiosis, but its specific regulatory mechanisms remain unknown. Herein, we report that DYNLRB2 (Dynein light chain roadblock-type-2) is a male meiosis-upregulated dynein light chain that is indispensable for spindle formation in meiosis I. In Dynlrb2 KO mouse testes, meiosis progression is arrested in metaphase I due to the formation of multipolar spindles with fragmented pericentriolar material (PCM). DYNLRB2 inhibits PCM fragmentation through two distinct pathways; suppressing premature centriole disengagement and targeting NuMA (nuclear mitotic apparatus) to spindle poles. The ubiquitously expressed mitotic counterpart, DYNLRB1, has similar roles in mitotic cells and maintains spindle bipolarity by targeting NuMA and suppressing centriole overduplication. Our work demonstrates that two distinct dynein complexes containing DYNLRB1 or DYNLRB2 are separately used in mitotic and meiotic spindle formations, respectively, and that both have NuMA as a common target.


Asunto(s)
Dineínas , Huso Acromático , Ratones , Animales , Masculino , Dineínas/genética , Dineínas/metabolismo , Huso Acromático/metabolismo , Centrosoma/metabolismo , Meiosis , Metafase
11.
bioRxiv ; 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36747695

RESUMEN

Dynein is the primary minus-end-directed microtubule motor [1]. To achieve activation, dynein binds to the dynactin complex and an adaptor to form the "activated dynein complex" [2, 3]. The protein Lis1 aids activation by binding to dynein and promoting its association with dynactin and adaptor [4, 5]. Ndel1 and its orthologue Nde1 are dynein and Lis1 binding proteins that help control where dynein localizes within the cell [6]. Cell-based assays suggest that Ndel1/Nde1 also work with Lis1 to promote dynein activation, although the underlying mechanism is unclear [6]. Using purified proteins and quantitative binding assays, we found that Ndel1's C-terminal region contributes to binding to dynein and negatively regulates binding to Lis1. Using single-molecule imaging and protein biochemistry, we observed that Ndel1 inhibits dynein activation in two distinct ways. First, Ndel1 disfavors the formation of the activated dynein complex. We found that phosphomimetic mutations in Ndel1's C-terminal domain increase its ability to inhibit dynein-dynactin-adaptor complex formation. Second, we observed that Ndel1 interacts with dynein and Lis1 simultaneously and sequesters Lis1 away from its dynein binding site. In doing this, Ndel1 prevents Lis1-mediated dynein activation. Our work suggests that in vitro, Ndel1 is a negative regulator of dynein activation, which contrasts with cellular studies where Ndel1 promotes dynein activity. To reconcile our findings with previous work, we posit that Ndel1 functions to scaffold dynein and Lis1 together while keeping dynein in an inhibited state. We speculate that Ndel1 release can be triggered in cellular settings to allow for timed dynein activation.

12.
Rural Remote Health ; 23(1): 8100, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36802655

RESUMEN

INTRODUCTION: The shortage of GPs in Scotland is concerning, particularly in rural areas. There are many reasons why GPs are leaving general practice; however, satisfaction with working life is an important predictor of GP retention. The aim of this study was to compare the working lives and intentions to reduce work participation of rural GPs and GPs working elsewhere in Scotland. METHODS: Quantitative analysis of responses from a nationally representative survey of GPs in Scotland. GPs were classified as 'non-rural' or 'rural' and these groups were compared using univariate and multivariate statistical analysis on four domains of working lives (job satisfaction, job stressors and positive and negative job attributes) and four intentions to reduce work participation (reducing working hours, working abroad, leaving direct patient care and leaving medical work entirely). RESULTS: There were significant differences in characteristics between rural and non-rural GPs. After controlling for these differences, GP age and gender, rural GPs reported higher job satisfaction, lower job stressors, higher positive job attributes, and lower negative job attributes than GPs elsewhere. A significant interaction between gender and rurality was found for job satisfaction, indicating that it was rural female GPs who were more satisfied. Rural GPs were, however, more likely to intend to work abroad and leave medical work entirely within 5 years than other GPs. DISCUSSION: These findings corroborate research from around the world and have serious implications for the future care of patients in rural areas. Further research is urgently required to understand the drivers of these findings.


Asunto(s)
Médicos Generales , Humanos , Femenino , Estudios Transversales , Medicina Familiar y Comunitaria , Escocia , Encuestas y Cuestionarios , Satisfacción en el Trabajo , Atención Primaria de Salud
13.
Scott Med J ; 68(1): 14-20, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36250546

RESUMEN

BACKGROUND AND AIMS: The 'inverse care law', first described in 1971, results from a mismatch of healthcare need and healthcare supply in deprived areas. GPs in such areas struggle to cope with the high levels of demand resulting in shorter consultations and poorer patient outcomes. We compare recent national GP and patient satisfaction data to investigate the ongoing existence of this disparity in Scotland. METHODS AND RESULTS: Secondary analysis of cross-sectional national surveys (2017/2018) on upper and lower deprivation quintiles. GP measures; job satisfaction, job stressors, positive and negative job attributes. Patient measures; percentage positive responses per practice on survey questions on access and consultation quality. GPs in high deprivation areas reported lower job satisfaction and positive job attributes, and higher job stressors and negative job attributes compared with GPs in low deprivation areas. Patients living in high deprivation areas reported lower satisfaction with access and consultation quality than patients in low deprivation areas. These differences in GP and patient satisfaction persisted after adjusting for confounding variables. CONCLUSIONS: Lower GP work satisfaction in deprived areas was mirrored by lower patient satisfaction. These findings add to the evidence that the inverse care law persists in Scotland, over 50 years after it was first described.


Asunto(s)
Médicos Generales , Humanos , Satisfacción del Paciente , Satisfacción en el Trabajo , Estudios Transversales , Factores Socioeconómicos , Encuestas y Cuestionarios , Escocia
14.
Mult Scler Relat Disord ; 68: 104375, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36544304

RESUMEN

BACKGROUND: The Symbol Digit Modalities Test (SDMT), the most reliable and sensitive measure of cognition in people with multiple sclerosis (PwMS), is increasingly used in clinical trials and care. OBJECTIVES: We aimed to establish how SDMT performance is influenced by repeating forms and frequency of use in PwMS. METHODS: A retrospective analysis was completed on a large database of PwMS (n = 740) with multiple SDMT administrations. Change in SDMT performance was analyzed, accounting for frequency of tests and utilization of alternate- versus same-form conditions. RESULTS: SDMT administrations ranged from 2 to 14 per subject over a mean (SD) of 5.9 (4.5) years. Accounting for demographics, the mixed effects model revealed a significant main effect of SDMT exposures (1.8 point improvement per repetition, p = 0.001) and an interaction between time since previous SDMT and whether the same test form was administered in the previous administration (estimate=-1.1, p = 0.037). As well, SDMT decline is observed when testing intervals exceed two years (F = 9.69, p<0.001). CONCLUSION: Improvements in SDMT performance with repeated exposure, likely reflecting practice effects, were greatest when repeating the same SDMT form over briefer intervals. We recommend the use of alternate forms or analogous versions of timed symbol-digit coding particularly where samples are saturated with many administrations.


Asunto(s)
Trastornos del Conocimiento , Esclerosis Múltiple , Humanos , Esclerosis Múltiple/diagnóstico , Estudios Retrospectivos , Cognición , Pruebas Neuropsicológicas
15.
Rural Remote Health ; 22(3): 7270, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35818306

RESUMEN

INTRODUCTION: Like many countries around the world, Scotland faces a shortage of general practitioners (GPs) due to both recruitment and retention issues. Such workforce shortages are of particular concern in rural areas. There are many reasons why GPs are leaving general practice; however, satisfaction with working life is an important predictor of GP retention. It is important, therefore, to understand working life satisfaction of rural GPs. The purpose of this study was to compare the working lives and intentions to reduce work participation of rural GPs and GPs working elsewhere in Scotland. METHODS: This study was a quantitative analysis of survey data from the Scottish School of Primary Care national working lives survey. GPs were classified as working in 'non-rural' or 'rural' practices based on the Scottish Government's rural binary classification system, and were compared using univariate and multivariate statistical analysis on four domains of working lives: job satisfaction, job stressors, positive and negative job attributes, and four intentions to reduce work participation: reducing working hours, working abroad, leaving direct patient care and leaving medical work entirely. RESULTS: A total of 2465 GPs returned the survey, giving a response rate of 56%. Three-hundred and forty seven GPs who returned the survey worked in practices in rural areas (14.1%). Rural GPs were more likely to do out-of-hours work (p<0.001), to have worked in their practice for fewer years (p=0.014), to work in single-GP partnerships (p<0.001), and to work in practices with smaller list sizes (p<0.001), than GPs in non-rural settings. Compared with GPs elsewhere, rural GPs reported higher mean job satisfaction (5.23 v 5.39, respectively; p<0.005), lower mean job stressors (3.58 v 3.29; p<0.001) and lower mean negative job attributes (4.08 vs 3.78; p<0.001). These differences remained highly significant after controlling for potential confounders (age, gender and the differences in work practices shown above). In regression analysis, a significant interaction was found between gender and rurality for job satisfaction (p=0.008), which indicated that rural female GPs' higher job satisfaction mainly accounted for rural GPs' increased job satisfaction. No significant interaction was found between gender and rurality for the other domains of working lives. Compared with GPs elsewhere, however, rural GPs were more likely to intend to work abroad (mean 1.39 v 1.55; p=0.013) and leave medical work entirely within 5 years (mean 2.15 v 2.36; p=0.039). These intentions remained significant after controlling for potential confounders. No significant interaction was found between gender and rurality for variables for intentions to reduce work participation. CONCLUSION: Rural GPs in Scotland are more satisfied with their working lives than GPs working elsewhere in Scotland, which is mainly due to higher job satisfaction in female GPs in rural areas. Despite this, rural GPs as a whole have a higher intention to leave their job in the next 5 years than their non-rural counterparts. Although some of these differences are small, they may signal serious implications for the future care of patients in rural areas and require further research to understand the drivers of this.


Asunto(s)
Médicos Generales , Estudios Transversales , Femenino , Humanos , Satisfacción en el Trabajo , Atención Primaria de Salud , Escocia , Encuestas y Cuestionarios
16.
Elife ; 112022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35703493

RESUMEN

Dynein harnesses ATP hydrolysis to move cargo on microtubules in multiple biological contexts. Dynein meets a unique challenge in meiosis by moving chromosomes tethered to the nuclear envelope to facilitate homolog pairing essential for gametogenesis. Though processive dynein motility requires binding to an activating adaptor, the identity of the activating adaptor required for dynein to move meiotic chromosomes is unknown. We show that the meiosis-specific nuclear-envelope protein KASH5 is a dynein activating adaptor: KASH5 directly binds dynein using a mechanism conserved among activating adaptors and converts dynein into a processive motor. We map the dynein-binding surface of KASH5, identifying mutations that abrogate dynein binding in vitro and disrupt recruitment of the dynein machinery to the nuclear envelope in cultured cells and mouse spermatocytes in vivo. Our study identifies KASH5 as the first transmembrane dynein activating adaptor and provides molecular insights into how it activates dynein during meiosis.


Asunto(s)
Dineínas , Proteínas Asociadas a Microtúbulos , Animales , Segregación Cromosómica , Complejo Dinactina/metabolismo , Dineínas/genética , Dineínas/metabolismo , Masculino , Meiosis , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo
17.
Front Cell Dev Biol ; 10: 871935, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35493069

RESUMEN

Cytoplasmic dynein-1 (dynein) is the primary microtubule minus-end directed molecular motor in most eukaryotes. As such, dynein has a broad array of functions that range from driving retrograde-directed cargo trafficking to forming and focusing the mitotic spindle. Dynein does not function in isolation. Instead, a network of regulatory proteins mediate dynein's interaction with cargo and modulate dynein's ability to engage with and move on the microtubule track. A flurry of research over the past decade has revealed the function and mechanism of many of dynein's regulators, including Lis1, dynactin, and a family of proteins called activating adaptors. However, the mechanistic details of two of dynein's important binding partners, the paralogs Nde1 and Ndel1, have remained elusive. While genetic studies have firmly established Nde1/Ndel1 as players in the dynein transport pathway, the nature of how they regulate dynein activity is unknown. In this review, we will compare Ndel1 and Nde1 with a focus on discerning if the proteins are functionally redundant, outline the data that places Nde1/Ndel1 in the dynein transport pathway, and explore the literature supporting and opposing the predominant hypothesis about Nde1/Ndel1's molecular effect on dynein activity.

18.
J Clin Exp Neuropsychol ; 44(1): 42-49, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35466856

RESUMEN

OBJECTIVE: This study investigated the performance on, and correlates of, the Brief Visuospatial Memory Test - Revised (BVMT-R) in patients with traumatic brain injury (TBI). METHODS: Participants included 100 patients with TBI and 100 demographically matched controls. We first used regression analysis to determine predictors of BVMT-R performance in the clinical group. We then used analysis of variance as well as logistic regression to determine how BVMT-R findings differed between the clinical and control groups. RESULTS: Injury severity and visuospatial ability both contributed to the prediction of BVMT-R Total Recall and Delayed Recall scores in the TBI group. Mean differences between the TBI and control groups on these variables were statistically significant, but overall individual classification accuracy was limited at 59%. CONCLUSIONS: The BVMT-R has some clinical utility in the evaluation of patients with TBI but should not be used in isolation.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Memoria , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/diagnóstico , Cognición , Humanos , Pruebas Neuropsicológicas
19.
Lancet Infect Dis ; 22(6): 857-866, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35305317

RESUMEN

BACKGROUND: In animal, epidemiological, and human challenge studies, a pre-existing T-cell response to internal proteins of influenza A has been associated with improved virological and disease outcomes. The aim of this study was to assess whether inducing additional responses to conserved CD4 and CD8 T-cell antigens provides added benefit to standard influenza vaccination. METHODS: We designed a phase 2b, randomised, placebo-controlled, double-blind trial of a recombinant viral-vectored vaccine (modified vaccinia Ankara expressing virus nucleoprotein and matrix protein 1; MVA-NP+M1), which has been shown to induce both CD4 and CD8 T cells, at eight outpatient clinical trial sites in Australia over two consecutive influenza seasons. We recruited non-immunosuppressed adults (≥18 years) who had received the 2019 quadrivalent influenza vaccine (QIV) vaccine within 28 days before study enrolment and randomisation (day 0). Participants were randomly assigned (1:1) according to a computer-generated random sequence to receive one dose of 1·5 × 108 plaque-forming units of MVA-NP+M1 or saline (placebo) intramuscularly. Randomisation was stratified by age (<65 years or ≥65 years). The patients and trial assessors were masked to treatment assignment. During the subsequent influenza seasons, participants with symptoms related to respiratory illness or influenza-like illness were to attend the clinic within 72 h of symptom onset for two nasal swabs for influenza testing by quantitative RT-PCR. The primary endpoint was the incidence rate of laboratory-confirmed influenza in the intention-to-treat (ITT) population. Safety (solicited adverse events within 7 days and unsolicited adverse events within 28 days after study vaccination, and serious adverse events for the study duration) was assessed in all randomly assigned participants who received at least one vaccination (according to the treatment received). The trial is registered with ClinicalTrials.gov, NCT03880474. FINDINGS: Between April 2 and June 14, 2019, 2152 adults were randomly allocated and received MVA-NP+M1 (n=1077) or placebo (n=1075), comprising the efficacy (ITT) analysis set. Participants were followed up throughout the 2019 Australia influenza season (May 1 to Oct 15, 2019). 419 (19·5%) of 2152 participants were aged 65 years or older. The incidence of laboratory-confirmed influenza did not differ between the MVA-NP+M1 group (35 of 1077 participants; 3·25% [95% CI 2·31-4·44]) and the placebo group (23 of 1075; 2·14% [1·39-3·14]; Fisher's exact p=0·14). 23 severe solicited local injection site reactions were reported in 13 (0·6%) of 2152 participants, 22 of which were reported in the MVA-NP + M1 group (in 12 [1·1%] participants). 100 severe systemic events were reported in 45 (4·2%) MVA-NP + M1 recipients, and 20 were reported in 14 (1·3%) placebo recipients. Three unsolicited grade 3 events in three participants (two headache and one nausea, all in the MVA-NP+M1 group) were deemed vaccine related. 21 serious adverse events were reported in 18 (1·7%) of 1077 participants in the MVA-NP+M1 group and 25 serious adverse events were reported in 22 (2·0%) of 1075 participants in the placebo group; none were considered vaccine related. The trial was stopped after one season for futility on the recommendation of the data monitoring committee. INTERPRETATION: MVA-NP+M1 was well tolerated with no vaccine-associated serious adverse events. A vaccine designed to induce moderate T-cell responses to the cross-reactive internal proteins of influenza A did not lead to improved incidence when given within 28 days after standard QIV immunisation. A greater magnitude of T-cell response with a different vaccine or regimen, or localisation in the lungs via alternative delivery, such as intranasal or aerosol, might be successful and require further investigation. FUNDING: Vaccitech.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Animales , Método Doble Ciego , Humanos , Vacunas contra la Influenza/efectos adversos , Gripe Humana/prevención & control , Estaciones del Año , Vacunación , Vacunas Combinadas , Virus Vaccinia
20.
Elife ; 112022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34994688

RESUMEN

The lissencephaly 1 gene, LIS1, is mutated in patients with the neurodevelopmental disease lissencephaly. The Lis1 protein is conserved from fungi to mammals and is a key regulator of cytoplasmic dynein-1, the major minus-end-directed microtubule motor in many eukaryotes. Lis1 is the only dynein regulator known to bind directly to dynein's motor domain, and by doing so alters dynein's mechanochemistry. Lis1 is required for the formation of fully active dynein complexes, which also contain essential cofactors: dynactin and an activating adaptor. Here, we report the first high-resolution structure of the yeast dynein-Lis1 complex. Our 3.1 Å structure reveals, in molecular detail, the major contacts between dynein and Lis1 and between Lis1's ß-propellers. Structure-guided mutations in Lis1 and dynein show that these contacts are required for Lis1's ability to form fully active human dynein complexes and to regulate yeast dynein's mechanochemistry and in vivo function.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/genética , Dineínas Citoplasmáticas/genética , Dineínas/genética , Regulación de la Expresión Génica , Proteínas Asociadas a Microtúbulos/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , 1-Alquil-2-acetilglicerofosfocolina Esterasa/química , 1-Alquil-2-acetilglicerofosfocolina Esterasa/metabolismo , Dineínas Citoplasmáticas/metabolismo , Dineínas/metabolismo , Dineínas/ultraestructura , Proteínas Asociadas a Microtúbulos/química , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo
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