RESUMEN
Introduction: myoActivation® assessment utilizes systemized movement tests to assess for pain and limitations in motion secondary to myofascial dysfunction. myoActivation needling therapy resolves the myofascial components of pain and is associated with immediately observed changes in pain, flexibility, and range of motion. The principal aim of this feasibility study was to objectively characterize the kinematic metrics of upper and lower body motion before and after myoActivation movement tests and therapy. Methods: Five consecutive eligible adolescent participants considered appropriate for myoActivation were consented to receive their myoActivation intervention in a motion laboratory. Clinical motion analysis was used to measure the changes in maximum range of motion (maxROM) and maximum angular speed to maximum ROM (speedROM) of movement tests predicted to change. Metrics were analyzed to assess changes over specified time intervals - i) baseline to after initial myoActivation session, and ii) baseline to after complete myoActivation course. Each participant served as their own control. Results: We demonstrated objective evidence of improved maxROM and/or speedROM in 63% of the movement tests predicted to change after just one session of myoActivation and in 77% of movement tests predicted to change over the complete course of treatment. The myoActivation clinician observed positive change in 11/19 of movement tests across all patients, that were predicted to change after the initial myoActivation session; 81% of these positive changes were confirmed by the kinematic data. Discussion: Clinical motion analysis provides objective support to clinicians evaluating, treating, and teaching myofascial release. A larger, prospective clinical trial is warranted to explore the impact of myoActivation on movement. Refinement of observation techniques and outcome measures established in this feasibility study will strengthen future clinical motion analysis of the myoActivation process.
RESUMEN
BACKGROUND: In this paper, we present the protocol for a cluster randomised controlled trial to evaluate the effectiveness and implementation of a participative risk management intervention to address work-related musculoskeletal disorders (WMSDs). The aims of the study include to evaluate the implementation process and the impact of the intervention on work related musculoskeletal pain and discomfort and exposure to physical and psychosocial hazards in paramedics over a 12-month period. METHODS: The intervention in this study is to implement A Participative Hazard Identification and Risk Management (APHIRM) toolkit in an ambulance service. Eighteen work groups containing eligible participants (registered paramedics) will be randomised into the intervention or wait-list control arm in one of three rolling recruitment periods. The APHIRM toolkit survey will be offered at baseline and 12 months later, to all current eligible participants in each work group allocated to the trial. The intervention work groups will receive the remainder of the APHIRM toolkit procedures. Identifying data about individual participants will not be collected in the survey, to protect participant privacy and encourage participation. Changes in primary (musculoskeletal pain and discomfort) and secondary (exposure to physical and psychosocial hazards at work) outcomes measured in the survey will be analysed comparing the baseline and follow up response of the cluster. A process evaluation is included to analyse the implementation and associated barriers or facilitators. DISCUSSION: This study is important in providing a comprehensive approach which focusses on both physical and psychosocial hazards using worker participation, to address WMSDs, a well-known and significant problem for ambulance services. The effectiveness of the intervention in work groups will be rigorously evaluated. If significant positive results are observed, the intervention may be adopted in ambulance services, both nationally and internationally. TRIAL REGISTRATION: ISRCTN77150219. Registered 21 November 2021.
Asunto(s)
Dolor Musculoesquelético , Humanos , Dolor Musculoesquelético/diagnóstico , Dolor Musculoesquelético/prevención & control , Paramédico , Ergonomía , Examen Físico , Gestión de Riesgos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
AIM: To test the feasibility of a study protocol that compared the efficacy of neutral- and negative-pressure needleless connectors (NCs). DESIGN: A single-centre, parallel-group, pilot randomised control trial. METHODS: Our study compared neutral-(intervention) and negative-pressure (control) NCs among adult patients in an Australian hospital. The primary feasibility outcome was measured against predetermined criteria (e.g. eligibility, attrition). The primary efficacy outcome was all-cause peripheral intravenous catheter failure, analysed as time-to-event data. RESULTS: In total, 201 (100 control; 101 intervention) participants were enrolled between March 2020 and September 2020. All feasibility criteria were met except eligibility, which was lower (78%) than the 90% criterion. All-cause peripheral intravenous catheter failure was significantly higher in the intervention group (39%) compared to control (19%). CONCLUSION: With minor modifications to participant screening for eligibility, this randomised control trial is feasible for a large multicentre randomised control trial. The neutral NC was associated with an increased risk of peripheral intravenous catheter failure. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: There are several NC designs available, often identified by their mechanism of pressure (positive, negative and neutral). However, NCs can contribute to peripheral intravenous catheter failure. This is the first randomised controlled trial to compare neutral and negative NC designs. Negative pressure NCs had lower PIVC failure compared to neutral NCs, however the results might not be generalisable to other brands or treatment settings. Further high-quality research is needed to explore NC design. REPORTING METHOD: Study methods and results reported in adherence to the CONSORT Statement. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.
RESUMEN
Background: Mobile apps for health (mHealth) have the potential to support people living with dementia. However, dementia is a complex and progressive condition that imposes specific constraints on the introduction/use of mhealth. Few studies have explored mHealth adoption and use within the complexity of everyday domestic settings. This study used an existing App co-designed with people living with mild cognitive and communication impairment (PWMCCI) due to learning disabilities and examined the usefulness for PWMICCI due to dementia and their carers. Methods: A qualitative study of people with dementia and their carers. Data were collected in a phased approach to identify the potential need for, as well as the usability and utility of the app. Analysis employed the Domestication of Technology Model (DTM) to explore, in a novel way mHealth, in this user group(s). Results: Most participants did not adopt the mHealth during the study period but some (n = 2) did routinely as it fulfilled a unique, unmet need. The use of DTM highlighted the complexities of dementia, pressure on carers and duplication of effort created barriers to app adoption and use in the long term. Conclusions: The ability of mHealth to support PWMCCI due to dementia and/or their carers may have potential. Users were motivated to try the technology but for any potential to be fully realised, the interplay between complexity of the condition including its progressive nature, demand on carers and nature of the technology needs to be more fully understood. Such issues place unique constraints around the size and window of opportunities for mHealth in this user group.
RESUMEN
Importance: Obstructive sleep-disordered breathing (SDB) in children is characterized by snoring and difficulty breathing during sleep. SDB affects at least 12% of otherwise healthy children and is associated with significant morbidity. Evidence from small clinical trials suggests that intranasal corticosteroids improve SDB as measured by polysomnography; however, the effect on symptoms and quality of life is unclear. Objective: To determine whether intranasal mometasone furoate is more effective than intranasal saline for improving symptoms and quality of life in children with SDB. Design, Setting, and Participants: The MIST trial was a multicenter, randomized, double-blind, placebo-controlled trial, recruiting participants from June 8, 2018, to February 13, 2020. Children aged 3 to 12 years who were referred to a specialist for significant SDB symptoms were included; exclusions were previous adenotonsillectomy, body mass index greater than the 97th percentile, and severe SDB. Randomization was stratified by site, and data were analyzed on an intention-to-treat basis from October 28, 2020, to September 25, 2022. Interventions: Participants were randomly assigned to receive mometasone furoate, 50 µg, or sodium chloride (saline), 0.9%, 1 spray per nostril daily, dispensed in identical bottles. Main Outcomes and Measures: The primary outcome was resolution of significant SDB symptoms (ie, reduction to a level no longer requiring referral to a specialist as per the American Academy of Pediatrics guidelines) at 6 weeks, measured by parental report of symptoms using the SDB Score. Results: A total of 276 participants (mean [SD] age, 6.1 [2.3] years; 146 male individuals [53%]) were recruited, 138 in each treatment arm. Resolution of significant SDB symptoms occurred in 56 of 127 participants (44%) in the mometasone group and 50 of 123 participants (41%) in the saline group (risk difference, 4%; 95% CI, -8% to 16%; P = .51) with 26 participants lost to follow-up and missing values managed by multiple imputation. The main adverse effects were epistaxis, affecting 12 of 124 participants (9.7%) in the mometasone group and 18 of 120 participants (15%) in the saline group, and nasal itch/irritation, affecting 12 of 124 participants (9.7%) in the mometasone group and 22 of 120 participants (18%) in the saline group. Conclusions and Relevance: Results of this randomized clinical trial suggest that there was no difference in treatment effect between intranasal mometasone and saline for the management of SDB symptoms. The results suggest that almost one-half of children with SDB could be initially managed in the primary care setting and may not require referral to specialist services, as is currently recommended. Trial Registration: Australian New Zealand Clinical Trials Registry: ANZCTRN12618000448246.
Asunto(s)
Calidad de Vida , Síndromes de la Apnea del Sueño , Masculino , Humanos , Niño , Furoato de Mometasona , Rociadores Nasales , Australia , Administración Intranasal , Prurito , Solución Salina , Resultado del TratamientoRESUMEN
Membrane modulation is a key part of cellular life. Critical to processes like energy production, cell division, trafficking, migration and even pathogen entry, defects in membrane modulation are often associated with diseases. Studying the molecular mechanisms of membrane modulation is challenging due to the highly dynamic nature of the oligomeric assemblies involved, which adopt multiple conformations depending on the precise event they are participating in. With the development of electron cryo-tomography and subtomogram averaging, many of these challenges are being resolved as it is now possible to observe complex macromolecular assemblies inside a cell at nanometre to sub-nanometre resolutions. Here, we review the different ways electron cryo-tomography is being used to help uncover the molecular mechanisms used by cells to shape their membranes.
Asunto(s)
Tomografía con Microscopio Electrónico , Electrones , Microscopía por Crioelectrón/métodos , Tomografía con Microscopio Electrónico/métodos , Sustancias MacromolecularesRESUMEN
Cells of most bacterial species are around 2 micrometers in length, with some of the largest specimens reaching 750 micrometers. Using fluorescence, x-ray, and electron microscopy in conjunction with genome sequencing, we characterized Candidatus (Ca.) Thiomargarita magnifica, a bacterium that has an average cell length greater than 9000 micrometers and is visible to the naked eye. These cells grow orders of magnitude over theoretical limits for bacterial cell size, display unprecedented polyploidy of more than half a million copies of a very large genome, and undergo a dimorphic life cycle with asymmetric segregation of chromosomes into daughter cells. These features, along with compartmentalization of genomic material and ribosomes in translationally active organelles bound by bioenergetic membranes, indicate gain of complexity in the Thiomargarita lineage and challenge traditional concepts of bacterial cells.
Asunto(s)
ADN Bacteriano , Orgánulos , Thiotrichaceae , Variaciones en el Número de Copia de ADN , ADN Bacteriano/análisis , ADN Bacteriano/metabolismo , Estadios del Ciclo de Vida , Orgánulos/química , Orgánulos/metabolismo , Poliploidía , Thiotrichaceae/genética , Thiotrichaceae/crecimiento & desarrollo , Thiotrichaceae/ultraestructuraRESUMEN
The sperm calcium channel CatSper plays a central role in successful fertilization as a primary Ca2+ gateway. Here, we applied cryo-electron tomography to visualize the higher-order organization of the native CatSper complex in intact mammalian sperm. The repeating CatSper units form long zigzag-rows along mouse and human sperm flagella. Above each tetrameric channel pore, most of the extracellular domains form a canopy that interconnects to a zigzag-shaped roof. Murine CatSper contains an additional wing-structure connected to the tetrameric channel. The intracellular domains link two neighboring channels to a diagonal array, suggesting a dimer formation. Fitting of an atomic model of isolated monomeric CatSper to the in situ map reveals supramolecular interactions and assembly of the CatSper complex. Loss of EFCAB9-CATSPERζ alters the architecture and interactions of the channels, resulting in fragmentation and misalignment of the zigzag-rows and disruption of flagellar movement in Efcab9-/- sperm. This work offers unique insights into the structural basis for understanding CatSper regulation of sperm motility.
Asunto(s)
Motilidad Espermática , Cola del Espermatozoide , Animales , Calcio/metabolismo , Canales de Calcio/fisiología , Membrana Celular/metabolismo , Masculino , Mamíferos/metabolismo , Ratones , Motilidad Espermática/fisiología , Cola del Espermatozoide/metabolismo , Espermatozoides/metabolismoRESUMEN
Lipid A, the membrane-anchored portion of lipopolysaccharide (LPS), is an essential component of the outer membrane (OM) of nearly all Gram-negative bacteria. Here we identify regulatory and structural factors that together render lipid A nonessential in Caulobacter crescentus. Mutations in the ferric uptake regulator fur allow Caulobacter to survive in the absence of either LpxC, which catalyzes an early step of lipid A synthesis, or CtpA, a tyrosine phosphatase homolog we find is needed for wild-type lipid A structure and abundance. Alterations in Fur-regulated processes, rather than iron status per se, underlie the ability to survive when lipid A synthesis is blocked. Fitness of lipid A-deficient Caulobacter requires an anionic sphingolipid, ceramide phosphoglycerate (CPG), which also mediates sensitivity to the antibiotic colistin. Our results demonstrate that, in an altered regulatory landscape, anionic sphingolipids can support the integrity of a lipid A-deficient OM.
Asunto(s)
Caulobacter crescentus , Caulobacter , Caulobacter crescentus/genética , Lípido A , Lipopolisacáridos , EsfingolípidosRESUMEN
Actin assembly provides force for a multitude of cellular processes. Compared to actin-assembly-based force production during cell migration, relatively little is understood about how actin assembly generates pulling forces for vesicle formation. Here, cryo-electron tomography identified actin filament number, organization, and orientation during clathrin-mediated endocytosis in human SK-MEL-2 cells, showing that force generation is robust despite variance in network organization. Actin dynamics simulations incorporating a measured branch angle indicate that sufficient force to drive membrane internalization is generated through polymerization and that assembly is triggered from â¼4 founding "mother" filaments, consistent with tomography data. Hip1R actin filament anchoring points are present along the entire endocytic invagination, where simulations show that it is key to pulling force generation, and along the neck, where it targets filament growth and makes internalization more robust. Actin organization described here allowed direct translation of structure to mechanism with broad implications for other actin-driven processes.
Asunto(s)
Actinas , Tomografía con Microscopio Electrónico , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Clatrina/metabolismo , Citoesqueleto/metabolismo , Endocitosis , HumanosRESUMEN
Background: During a pandemic, public transport is strategically important for keeping the country going and getting people where they need to be. The essential nature of public transport puts into focus the risk of transmission of SARS-CoV-2 in this sector; rapid and diverse work has been done to attempt to understand how transmission happens in this context and what factors influence risk. Objectives: This review aimed to provide a narrative overview of the literature assessing transmission, or potential for transmission, of SARS-CoV-2 on ground-based public transport, as well as studies assessing the effectiveness of control measures on public transport during the early part of the pandemic (up to May 2021). Methods: An electronic search was conducted using Web of Science, Ovid, the Cochrane Library, ProQuest, Pubmed, and the WHO global COVID database. Searches were run between December 2020 and May 2021. Results: The search strategy identified 734 papers, of which 28 papers met the inclusion criteria for the review; 10 papers assessed transmission of SARS-CoV-2, 11 assessed control measures, and seven assessed levels of contamination. Eleven papers were based on modelling approaches; 17 studies were original studies reporting empirical COVID-19 data. Conclusions: The literature is heterogeneous, and there are challenges for measurement of transmission in this setting. There is evidence for transmission in certain cases, and mixed evidence for the presence of viral RNA in transport settings; there is also evidence for some reduction of risk through mitigation. However, the routes of transmission and key factors contributing to transmission of SARS-CoV-2 on public transport were not clear during the early stage of the pandemic. Gaps in understanding are discussed and six key questions for future research have been posed. Further exploration of transmission factors and effectiveness of mitigation strategies is required in order to support decision making.
RESUMEN
OBJECTIVE: Cleft palate (CP) can affect breathing, leading to sleep-disordered breathing (SDB). Sleep position can affect SDB, but the optimum sleep position for infants with CP is unknown. We aimed to determine the design of a pragmatic study to investigate the effect of the 2 routinely advised sleep positions in infants with CP on oxygen saturations. DESIGN: A multicentered observational cohort. SETTING: Four UK-based cleft centers, 2 advising supine- and 2 side-lying sleep positions for infants with CP. PARTICIPANTS: Infants with isolated CP born July 1, 2015, and December 31, 2016. Of 48 eligible infants, 30 consented (17 side-lying; 13 supine). INTERVENTIONS: Oxygen saturation (SpO2) and end-tidal carbon dioxide (ETCO2) home monitoring at age 1 and 3 months. Qualitative interviews of parents. OUTCOME MEASURES: Willingness to participate, recruitment, retention, and acceptability/success (>90 minutes recording) of SpO2 and ETCO2 monitoring. RESULTS: SpO2 recordings were obtained during 50 sleep sessions on 24 babies (13 side-lying) at 1 month (34 sessions >90 minutes) and 50 sessions on 19 babies (10 side-lying) at 3 months (27 sessions >90 minutes). The ETCO2 monitoring was only achieved in 12 sessions at 1 month and 6 at 3 months; only 1 was >90 minutes long. The ETCO2 monitoring was reported by the majority as unacceptable. Parents consistently reported the topic of sleep position in CP to be of importance. CONCLUSIONS: This study has demonstrated that it is feasible to perform domiciliary oxygen saturation studies in a research setting and has suggested that there may be a difference in the effects of sleep position that requires further investigation. We propose a study with randomization is indicated, comparing side-lying with supine-lying sleep position, representing an important step toward better understanding of SDB in infants with CP.
Asunto(s)
Fisura del Paladar , Síndromes de la Apnea del Sueño , Estudios de Cohortes , Estudios de Factibilidad , Humanos , Lactante , Sueño , Posición SupinaRESUMEN
In England, care to support people living at home is largely commissioned by local authorities (statutory organisations with responsibility for social care in specific localities) from non-statutory home-care providers (for-profit, not-for-profit, voluntary). This paper explores how managers of these services perceive commissioning arrangements and their impact on home-care providers, the care workforce and service users. Little formal research of providers' experiences of working with local authorities in a commissioning model is available. A qualitative study employed semi-structured telephone interviews with 20 managers of for-profit home-care providers from 10 selected local authority areas in England. Data were analysed using thematic analysis to identify main and subsidiary themes. Home-care providers reported operating in a complex and changeable partnership with commissioners, characterised by: (a) relationships ranging from transactional to collaborative, (b) providers expressing a strong sense of public service motivation, (c) commissioning practices that were complex to negotiate, time-consuming and overly prescriptive, (d) frequent changes in commissioning practices and a perceived lack of strategic planning, which were reported as contributing to uncertainty and tension for providers and confusion for service users. Attempting to operate a market model with tightly prescribed contracts is likely to be unsustainable. An alternative approach based on a collaborative model of joint responsibility for providing home care is recommended drawing on a conceptual framework of principal-steward relationships in contracting.
Asunto(s)
Servicios de Atención de Salud a Domicilio , Anciano , Inglaterra , Humanos , Investigación Cualitativa , Apoyo Social , Medicina EstatalRESUMEN
BACKGROUND: There is a growing interest in using mobile apps to support communication, safety, and well-being. Evidence directly from people with dementia regarding the usability, usefulness, and relevance of mobile apps is limited. OBJECTIVE: This paper describes the protocol of a study that will evaluate an app designed for supporting communication, safety, and well-being among people living with dementia. The study aims to understand if the app can enhance safety through improved communication among users. METHODS: The study will use participatory qualitative methods over 3 cycles of evaluation with co-designers (service users, their families, and care practitioners). The study will be developed in partnership with a specialist home care service in England. Purposive case selection will be performed to ensure that the cases exemplify differences in experiences. The app will be evaluated in a walk-through workshop by people living with early-stage dementia and then trialed at home by up to 12 families in a try-out cycle. An amended version will be evaluated in a final walk-through workshop during cycle 3. Data will be collected from at least 4 data sources during the try-out phase and analyzed thematically. An explanatory multiple case study design will be used to synthesize and present the evidence from the three cycles, drawing on the Normalization Process Theory to support the interpretation of the findings. RESULTS: The study is ready to be implemented, but it was paused to protect vulnerable individuals during the COVID-19 pandemic in 2020. The findings will be particularly relevant for understanding how to support vulnerable people living in the community during social distancing and the period following the pandemic as well as for providing insight into the challenges of social isolation that arise from living with dementia. CONCLUSIONS: Evaluating a mobile app for enhancing communication, safety, and well-being among people living with dementia contributes to the key ambitions enshrined in policy and practice-championing the use of digital technology and supporting people with dementia to live safely in their own homes. The study will involve co-designers living with dementia, so that the voices of service users can be used to highlight the benefits and challenges of assistive technology and shape the future development of apps that enhance safety by improving communication. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/19543.
RESUMEN
BACKGROUND: The number of individuals with a visual impairment in the UK was estimated a few years ago to be around 1.8 million. People can be visually impaired from birth, childhood, early adulthood or later in life. Those with visual impairment are subject to health inequities and increased risk for patient safety incidents in comparison to the general population. They are also known to be at an increased risk of experiencing medication errors compared to those without visual impairment. In view of this, this review aims to understand the issues of medication safety for VI people. METHODS/DESIGN: Four electronic bibliographic databases will be searched: MEDLINE, Embase, PsycInfo and CINAHL. Our search strategy will include search combinations of two key blocks of terms. Studies will not be excluded based on design. Included studies will be empirical studies. They will include studies that relate to both medication safety and visual impairment. Two reviewers (SG and LR) will screen all the titles and abstracts. SG, LR, RM, SCS and PL will perform study selection and data extraction using standard forms. Disagreements will be resolved through discussion or third party adjudication. Data to be collected will include study characteristics (year, objective, research method, setting, country), participant characteristics (number, age, gender, diagnoses), medication safety incident type and characteristics. DISCUSSION: The review will summarise the literature relating to medication safety and visual impairment.
Asunto(s)
Errores de Medicación , Seguridad del Paciente , Adulto , Niño , Humanos , Proyectos de Investigación , Literatura de Revisión como Asunto , Trastornos de la Visión/inducido químicamenteRESUMEN
Mouse models of Alzheimer's disease (AD) are valuable but do not fully recapitulate human AD pathology, such as spontaneous Tau fibril accumulation and neuronal loss, necessitating the development of new AD models. The transgenic (TG) TgF344-AD rat has been reported to develop age-dependent AD features including neuronal loss and neurofibrillary tangles, despite only expressing APP and PSEN1 mutations, suggesting an improved modelling of AD hallmarks. Alterations in neuronal networks as well as learning performance and cognition tasks have been reported in this model, but none have combined a longitudinal, multimodal approach across multiple centres, which mimics the approaches commonly taken in clinical studies. We therefore aimed to further characterise the progression of AD-like pathology and cognition in the TgF344-AD rat from young-adults (6 months (m)) to mid- (12 m) and advanced-stage (18 m, 25 m) of the disease. Methods: TgF344-AD rats and wild-type (WT) littermates were imaged at 6 m, 12 m and 18 m with [18F]DPA-714 (TSPO, neuroinflammation), [18F]Florbetaben (Aß) and [18F]ASEM (α7-nicotinic acetylcholine receptor) and with magnetic resonance spectroscopy (MRS) and with (S)-[18F]THK5117 (Tau) at 15 and 25 m. Behaviour tests were also performed at 6 m, 12 m and 18 m. Immunohistochemistry (CD11b, GFAP, Aß, NeuN, NeuroChrom) and Tau (S)-[18F]THK5117 autoradiography, immunohistochemistry and Western blot were also performed. Results: [18F]DPA-714 positron emission tomography (PET) showed an increase in neuroinflammation in TG vs wildtype animals from 12 m in the hippocampus (+11%), and at the advanced-stage AD in the hippocampus (+12%), the thalamus (+11%) and frontal cortex (+14%). This finding coincided with strong increases in brain microgliosis (CD11b) and astrogliosis (GFAP) at these time-points as assessed by immunohistochemistry. In vivo [18F]ASEM PET revealed an age-dependent increase uptake in the striatum and pallidum/nucleus basalis of Meynert in WT only, similar to that observed with this tracer in humans, resulting in TG being significantly lower than WT by 18 m. In vivo [18F]Florbetaben PET scanning detected Aß accumulation at 18 m, and (S)-[18F]THK5117 PET revealed subsequent Tau accumulation at 25m in hippocampal and cortical regions. Aß plaques were low but detectable by immunohistochemistry from 6 m, increasing further at 12 and 18 m with Tau-positive neurons adjacent to Aß plaques at 18 m. NeuroChrom (a pan neuronal marker) immunohistochemistry revealed a loss of neuronal staining at the Aß plaques locations, while NeuN labelling revealed an age-dependent decrease in hippocampal neuron number in both genotypes. Behavioural assessment using the novel object recognition task revealed that both WT & TgF344-AD animals discriminated the novel from familiar object at 3 m and 6 m of age. However, low levels of exploration observed in both genotypes at later time-points resulted in neither genotype successfully completing the task. Deficits in social interaction were only observed at 3 m in the TgF344-AD animals. By in vivo MRS, we showed a decrease in neuronal marker N-acetyl-aspartate in the hippocampus at 18 m (-18% vs age-matched WT, and -31% vs 6 m TG) and increased Taurine in the cortex of TG (+35% vs age-matched WT, and +55% vs 6 m TG). Conclusions: This multi-centre multi-modal study demonstrates, for the first time, alterations in brain metabolites, cholinergic receptors and neuroinflammation in vivo in this model, validated by robust ex vivo approaches. Our data confirm that, unlike mouse models, the TgF344-AD express Tau pathology that can be detected via PET, albeit later than by ex vivo techniques, and is a useful model to assess and longitudinally monitor early neurotransmission dysfunction and neuroinflammation in AD.
Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Espectroscopía de Resonancia Magnética , Placa Amiloide/metabolismo , Tomografía de Emisión de Positrones , Proteínas tau/metabolismo , Envejecimiento/metabolismo , Envejecimiento/fisiología , Enfermedad de Alzheimer/patología , Animales , Escala de Evaluación de la Conducta , Disfunción Cognitiva/genética , Disfunción Cognitiva/fisiopatología , Modelos Animales de Enfermedad , Femenino , Radioisótopos de Flúor , Lóbulo Frontal/metabolismo , Lóbulo Frontal/patología , Gliosis/metabolismo , Hipocampo/metabolismo , Hipocampo/patología , Inmunohistoquímica , Inflamación/metabolismo , Locomoción/genética , Locomoción/fisiología , Masculino , Neuronas/metabolismo , Neuronas/patología , Ratas , Ratas Transgénicas , Receptores Colinérgicos/metabolismo , Tálamo/metabolismo , Tálamo/patologíaRESUMEN
Cryo-electron tomography (cryo-ET) is an extremely powerful tool which is used to image cellular features in their close-to-native environment at a resolution where both protein structure and membrane morphology can be revealed. Compared to conventional electron microscopy methods for biology, cryo-ET does not include the use of potentially artifact generating agents for sample fixation or visualization. Despite its obvious advantages, cryo-ET has not been widely adopted by cell biologists. This might originate from the overwhelming and constantly growing number of complex ways to record and process data as well as the numerous methods available for sample preparation. In this chapter, we will take one step back and guide the reader through the essential steps of sample preparation using mammalian cells, as well as the basic steps involved in data recording and processing. The described protocol will allow the reader to obtain data that can be used for morphological analysis and precise measurements of biological structures in their cellular environment. Furthermore, this data can be used for more elaborate structural analysis by applying further image processing steps like subtomogram averaging, which is required to determine the structure of proteins.
Asunto(s)
Microscopía por Crioelectrón/métodos , Tomografía con Microscopio Electrónico/métodos , Técnicas de Cultivo de Célula , Línea Celular , Humanos , Imagenología TridimensionalRESUMEN
BACKGROUND: Peripheral intravenous catheters (PIVCs) are ubiquitous medical devices, crucial to providing essential fluids and drugs. However, post-insertion PIVC failure occurs frequently, likely due to inconsistent maintenance practice such as flushing. The aim of this implementation study was to evaluate the impact a multifaceted intervention centred on short PIVC maintenance had on patient outcomes. METHODS: This single-centre, incomplete, stepped wedge, cluster randomised trial with an implementation period was undertaken at a quaternary hospital in Queensland, Australia. Eligible patients were from general medical and surgical wards, aged ≥ 18 years, and requiring a PIVC for > 24 h. Wards were the unit of randomisation and allocation was concealed until the time of crossover to the implementation phase. Patients, clinicians, and researchers were not masked but infections were adjudicated by a physician masked to allocation. Practice during the control period was standard care (variable practice with manually prepared flushes of 0.9% sodium chloride). The intervention group received education reinforcing practice guidelines (including administration with manufacturer-prepared pre-filled flush syringes). The primary outcome was all-cause PIVC failure (as a composite of occlusion, infiltration, dislodgement, phlebitis, and primary bloodstream or local infection). Analysis was by intention-to-treat. RESULTS: Between July 2016 and February 2017, 619 patients from 9 clusters (wards) were enrolled (control n = 306, intervention n = 313), with 617 patients comprising the intention-to-treat population. PIVC failure was 91 (30%) in the control and 69 (22%) in the intervention group (risk difference - 8%, 95% CI - 14 to - 1, p = 0.032). Total costs were lower in the intervention group. No serious adverse events related to study intervention occurred. CONCLUSIONS: This study demonstrated the effectiveness of post-insertion PIVC flushing according to recommended guidelines. Evidence-based education, surveillance and products for post-insertion PIVC management are vital to improve patient outcomes. TRIAL REGISTRATION: Trial submitted for registration on 25 January 2016. Approved and retrospectively registered on 4 August 2016. Ref: ACTRN12616001035415 .